SEB sWorkshop on Fruit Development and Ripening
Session synopsis:
Fruits are typical plant organs and therefore their understanding their development is central to know how plants work. But fruits are also an
important source of healthy nutrients and therefore this knowledge could be used to impact fruit production and fruit quality. Although there has
been a huge progress in the identification of important regulators of fruit development and ripening in model plants we are still far from
understanding these processes, mainly when considering the large variability in fruit types that is exhibited in nature. The availability of the
genome sequence from several fruit crops such as tomato, vitis, peach, etc. as well as the initiation of projects such as Sol100 aiming to
sequence a large number of Solanaceae, is changing the way we approach fruit research and the speed in which genes affecting important fruit
traits are identified. Also it is changing the way we analyze gene function and screen for mutations. Genetic, biochemical and genomic studies
are unravelling for example the role of different hormones in fruit development and ripening, the function of transcriptional factors and
epigenetics in ripening regulation, and the identity of genes underlying important fruit traits. However there are still many questions which
remain poorly answered or entirely unexplored. This session brought together experts in various disciplines and working in different fruits to
present the latest advances in fruit development and ripening research and try to answer all those questions. The workshop covered nicely the
two model systems that are the foundation of COST1106, namely grape and tomato.
The workshop was a whole success in terms of number of participants and in the quality of the presentations. There were in total 17 oral
presentations, including 3 keynote speakers and other 14 other speakers from a total of eleven countries. Partners from COST1106 have the
opportunity to present their work either orally and/ or in a poster session that was held from the 3rd to the 6th of July in Valencia. There was also
plenty of time for discussion in and after the sessions, including coffee breaks and workshop dinner. There was also a meeting to discuss some of
the issues in relation to the second annual meeting to be held in Chania this coming September.
Organisers:
Graham Seymour, School of Biosciences, University of Nottingham. Graham.Seymour@nottingham.ac.uk
Antonio Granell, Fruit Genomics and Biotechnology, CSIC-IBMCP, Valencia, Spain. agranell@ibmcp.upv.es
Presentations included:
Ping Leng (China) pleng@cau.edu.cnm. Role of ABA in tomato fruit development and ripenin
Prof Mondher Bouzayen (France) “Multi-hormonal control of the transcriptional regulation associated with fruit development and ripening”.
bouzayen@ensat.fr
Dr. Cristina Ferrandiz (Spain) “the role of MADS-box genes in the evolution of seed dispersal strategies and fruit morphology”.
cferrandiz@ibmcp.upv.es
Dr Ruud A De Maagd (APETALA2a and two FRUITFULL orthologs) “Regulation of tomato fruit ripening by APETALA2a and two
FRUITFULL orthologs”. ruud.demaagd@wur.nl
Miss Qian Li (ABA) “Role of FaBG3 in fruit development and ripening of strawberry”. woshiliqian0204@126.com
Dr Sonia Dal Santo (Italy) Grapevine berry transcriptome
Dr. Charles Ampomah-Dwamena (New Zealand) “Transcription factors regulating carotenogenesis in
apple”.charles.dwamena@plantandfood.co.nz.
Prof James Giovannoni (USA) "Regulation of tomato fruit ripening: genes, genome, epigenome." ,jjg33@cornell.edu
Prof Graham B Seymour (UK) “tomato epigenetic variation” graham.seymour@nottingham.ac.uk
Dr Phillipe Gallusci (France) “Epigenetic control of tomato fruit development”. philippe.gallusci@bordeaux.inra.fr
Prof Asaph Aharoni (Israel) “Transcriptome and Metabolome Analysis for Gene Discovery in the Steroidal Alkaloid Pathway”.
asaph.aharoni@weizmann.ac.il
Dr Jocelyn K Rose (USa) “"Peeling Apart the Structure, Functions and Diversity of Fruit Cuticles". jr286@cornell.edu
Dr Alisdair R Fernie (Germany) “Secondary metabolism during fruit ripening”. fernie@mpimp-golm.mg.de
Prof Serge Delrot (France) “Grape berry development and ripening”. serge.delrot@bordeaux.inra.fr
Dr Antonio J Monforte (Spain) “The genetic control of fruit morphology in melon”. amonforte@ibmcp.ibmcp.upv.es
Prof Antonio Granell (volatile production in fruit)” Genomic approaches to unravel and reconstitute volatile production in fruit”.
agranell@ibmcp.upv.es
Dr Sofia Kourmpetli (Fruit Development in Opium Poppy) “Fruit Development in Opium Poppy and the Evolution of Fruit Form”.
sk425@le.ac.uk
ABSTRACTS:
Parthenocarpy in mutant population of Cucurbita pepo (Poster)
Teresa Pomares-Viciana (IFAPA, Spain), Nelly Vicente-Dólera (IFAPA, Spain), Manuel Moya (IFAPA, Spain), Pedro Gómez
(IFAPA, Spain)
Development of parthenocarpic fruit cultivars in agronomic species as Cucurbits is one of the main objectives in breeding
programs. Present work is focused on studying parthenocarpic fruit development (ability to set fruit without fertilization of the ovule)
in a mutant population of Cucurbita pepo. 1500 seeds were mutagenized with EMS 40 mM. Parthenocarpy has been evaluated in
mutagenized plants M1 by a quantitative method based on fruit growth in reference to a non-parthenocarpic line MU-CU 16 as
control. Six M2 parthenocarpic mutant lines were obtained. Parameters as germination rate, phenotypes in different development
stages and parthenocarpic fruits development were studied in M2 lines. Parthenocarpy was inusual (2,42%) compared with other
mutations as variegation (7,08 %) in M1 mutant population. M2 parthenocarpic mutant lines showed low germination rate, deformed
cotyledons and phenotypes as abnormal flower morphology and late growing and flowering that prevented M3 parthenocarpic
mutant lines in general. Present and future studies will focus on selecting partenocarpic families and determining if some of these
morphology phenotypes are associated with parthenocarpy.
Email Address for correspondence: teresa.pomares.ext@juntadeandalucia.es
The role of ABA in regulating fruit ripening and response to biotic/abiotic stress of fruits (Invited Talk)
Ping Leng (China Agricultural University, China)
The phytohormones abscisic acid (ABA) plays a crucial role not only in fruit development and ripening, but also in adaptive
responses to biotic and abiotic stresses. Endogenous ABA content is modulated by a dynamic balance between
biosynthesis,catabolism and reactivation, which are regulated by 9-cis-epoxycarotenoid dioxygenase (NCED), ABA 8’-hydroxylase
(CYP707As) and β-glucosidase (BGs) transcripts, respectively, in climacteric and non-climacteric fruits. Recently, multiple ABA
receptors localized to different subcellular sites have been identified. However, it remains unknown how the ABA levels in fruits are
finely controlled at the transcriptional level. To elucidate such a mechanism, it is necessary to identify all the components involved
in ABA homeostasis, including those that function in biosynthetic, catabolic and reactivation pathways, and those that play a role in
transport between compartments. Therefore we cloned genes involve in ABA metabolism and signaling, and investigated
transcriptional regulation of these genes. And we further verified the role of these candidate genes in fruit development and
biotic/abiotac stress, using RNA interference (RNAi) strategy in both climacteric (tomato) and non-climacteric fruits (strawberry and
cherry fruits). Our results are providing new clues and candidate genes that are expanding the known regulatory circuitry of
ripening. Finally, we suggest possible commercial applications of genetic manipulation of ABA signaling to improve fruit quality and
yields.
Email Address for correspondence: pleng@cau.edu.cn
Regulation of tomato fruit ripening by APETALA2a and two FRUITFULL orthologs
Invited talk
Ruud A De Maagd (Plant Research International, Netherlands), Karlova Rumyana (Utrecht University, Netherlands), Michiel
Lammers (Plant Research International, Netherlands), Violeta Parapunova (Wageningen University, Netherlands), Livia Trevisan
Scorza (Plant Research International, Netherlands), Gerco C Angenent (Plant Research International, Netherlands)
Several transcription factors known to regulate flowering, floral organ identity or silique expansion and dehiscence in Arabidopsis,
have orthologs in tomato that appear to regulate fruit ripening. We have identified and studied three of such transcription factors,
tomato APETALA2a (one of three AP2 co-orthologs) and SlFUL1/TDR4 with SlFUL2/MBP7 (two FRUITFULL co-orthologs). While
required for normal ripening to proceed, at the same time SlAP2a appears to be a negative regulator of ripening through inhibition
of ethylene production. SlFUL1 and SlFUL2 function redundantly in a number of apparantly ethylene-independent aspects of
ripening. Here we describe the functional characterization of these genes, and their possible place and role in the transcriptional
regulatory network controlling tomato fruit ripening.
Email Address for correspondence: ruud.demaagd@wur.nl
Analysis of temperate grass grain characters reveals distinctive patterns of endosperm organization associated with grain
shape (possible talk)
Philip Hands (University of Leicester, United Kingdom), Sinead Drea (University of Leicester, United Kingdom), Sofia Kourmpetli
(University of Leicester, United Kingdom), Sharples Donna (University of Leicester, United Kingdom), Harris Robert (University of
Leicester, United Kingdom)
Brachypodium is an important model for temperate grasses, in particular to the core-pooids, a significant group including major
crop species wheat, barley, and oats. The significance of these crops is largely due to the properties of their grain and endosperm
storage capabilities. The monogenic Brachypoideae is sister to the core-pooid tribes Poeae, Aveneae, Triticeae, and Bromeae, and
Brachypodium provides a taxonomically relevant reference point for comparative analysis. We used Brachypodium distachyon as a
reference point for surveying several characters of grain morphology and endosperm organization amongst wild and cultivated
core-pooids and other Brachypoideae species. Macroscopic, histological, and molecular analyses reveal distinct patterns of grain
tissue organization in these species. This comparison shows Brachypodium species to be distinct in both endosperm structure and
organisation with an irregular peripheral aleurone in contrast to other Pooideae species, and modified aleurone domain absent.
Results indicate aleurone organization is correlated with grain quality characters such as shape and starch content where low
endosperm starch reserves are generally linked to irregular peripheral aleurone, persistent nucellar epidermis and lack of distinctly
creased grain morphology. Ultimately a grain’s final properties are a consequence of developmental processes generating its
tissue organization. Preliminary identification and expression analysis of Brachypodium candidate regulatory genes potentially
underpinning variation was performed, revealing largely conserved patterns of expression. Many features commonly associated
with temperate cereal grain morphology have been defined in analyses of wheat and barley, and these results suggest that
knowledge of grain structure may be skewed as a result of this focus.
Email Address for correspondence: psh14@le.ac.uk
A multi-scale analysis of fruit growth of two tomato cultivars in response to fruit temperature (possible talk)
Robert Cyrus Okello Ongom (Wageningen University and Research Centre, Netherlands), Pieter De Visser (Wageningen
University and Research Centre, Netherlands), Ep Heuvelink (Wageningen University and Research Centre, Netherlands), Leo F.
M. Marcelis (Wageningen University and Research Centre, Netherlands), Paul C. Struik (Wageningen University and Research
Centre, Netherlands)
Fruit phenotype is a resultant of inherent genetic potential and environment experienced during growth. The aim of this study was
to explore the physiological basis for fruit size difference between two tomato cultivars (‘Brioso’, cherry tomato;‘Cappricia’, round
tomato) in interaction with temperature. Temperature response was investigated by varying fruit temperature from anthesis until
breaker stage using climate-controlled cuvettes. Fruit phenotype was observed at eight stages between anthesis and breaker
stage. It was hypothesized that high temperature enhances carbon import and leads to increase in cell division and expansion.
However, increase in cell number intensifies competition for assimilates among cells. In conjunction with reduced growth duration at
high temperature, the increased competition among cells leads to a decline in final cell and fruit size. Our findings suggest that: 1)
final fruit weight differences between these two contrasting cultivars is attributable to differences in cell number, cell volume and
fruit growth duration and rate, 2)reduction in fruit size at high temperature takes place through cell volume decrease and it occurs
despite an increase in cell number, and 3) heating has no effect on fruit carbohydrate content. These results reveal the tradeoff
between cell number and size as a result of increased intercellular competition for assimilates and reduced growth duration at high
temperature. Additional qPCR studies on the expression of 30 genes involved in cell cycle, endoreduplication and carbohydrate
metabolism regulation will be conducted to provide gene scale data necessary for modelling fruit growth following a systems
biology approach.
Email Address for correspondence: robertcyrus.okelloongom@wur.nl
A tomato QTL for fruit texture (Poster)
Selman Uluisik (Nottingham University, United Kingdom), Graham Seymour (Nottingham University, United Kingdom)
The cultivated tomato,Solanum lycopersicum, is of the most important fruit, on the basis of amount consumed both as a fresh and
processed product. Tomato is also the model for investigating the biological basis of ripening in fleshy fruits.
Fruit ripening is an important developmental process involving the expression of hundreds of genes that control the development of
colour, texture and flavour (Klee and Giovannoni, 2011). Texture is a particularly important quality attribute, but its molecular basis
is highly complex and still relatively poorly understood. Evidence indicates that texture of tomato involves numerous cell wall
remodelling events including pectin degradation caused by cell modifying enzymes such as, polygalacturonase, pectin
methylesterase and pectate lyase (Seymour et al, 2013).
In this project we are using the crop wild-species relativeSolanum pennelliito identify quantitative trait loci (QTL) for texture.
Introgression lines withS. pennelliisegmented in a genetic background ofS. lycopersicum(M82D) were previously screened and a
texture QTL identified on Chromosome 3. Initial experiments have mapped this effect to a 2.1 Mb interval on this chromosome. This
project aims to identify the gene under this texture QTL by further linkage mapping and then test candidate gene in transgenic
tomato fruits.
Email Address for correspondence: sbxsu@nottingham.ac.uk
Anatomy of fruit and fruit pedicel of tomato plants with normal or deficient ABA content (Poster)
Dragana Rancic (University of Belgrade Faculty of Agriculture, Serbia and Montenegro), Ilinka Pecinar (University of Belgrade
Faculty of Agriculture, Serbia and Montenegro), Sofija Pekic Quarrie (University of Belgrade Faculty of Agriculture, Serbia and
Montenegro), Maja Terzic (University of Belgrade Faculty of Agriculture, Serbia and Montenegro), Radenko Radosevic (University
of Belgrade Faculty of Agriculture, Serbia and Montenegro), Radmila Stikic (University of Belgrade Faculty of Agriculture, Serbia
and Montenegro)
This research aimed to compare anatomical parameters in fruit and fruit pedicel two tomato genotypes: wild type Ailsa Craig and its
ABA deficient mutant flacca. Plants were grown in chamber conditions. For anatomical investigations fruits were fixed in FAA and
transversal sections were done by standard paraffin technique. The thickness of pericarp and number of cells in pericarp wall were
measured. Functional analysis of vascular system in fruit pedicel was done by applying xylem and phloem mobile dyes. Fruits of
the ABA deficient mutant are smaller as consequence of smaller-sized cells in pericarp since functional xylem area in fruit pedicels
and diameter of xylem elements in both genotypes are similar. Wild type has more nonfunctional xylem that could serve as a
mechanical support for heavier fruits. Lower fruit dry weight and phloem efficiency in pedicels of ABA deficient mutant compared to
the wild type suggests important role of ABA in the fruit sink activity.
Email Address for correspondence: rancicd@agrif.bg.ac.rs
Auxin and gibberellin modulation of volatile production in tomato fruit (Poster)
Jose Luis Rambla (IBMCP, Spain), Clara Pons (IBMCP, Spain), Hua Wang (INPT, France), Mondher Bouzayen (INPT, France),
Antonio Granell (IBMCP, Spain)
A subset of the fruit volatiles are associated to tomato fruit ripening and contribute to make the fruit palatable and attractive to
consumers. In the case of tomato the importance of ethylene in regulating the different aspects of fruit ripening is known for long,
although no specific branch or ethylene regulated transcription factor has been reported to directly control ripening-associated
volatile production. The participation of hormones other than ethylene in modulating fruit volatiles was investigated in plants
engineered for gibberellins (asDELLA plants) or auxins (IAA9 RNAi plants) activated responses. These plants produce facultative
parthenocarpic fruits and therefore could also be used to test the effect of seedness on fruit metabolite profiling including volatile
compounds. While gibberellins main effect on volatiles was in the accumulation of higher levels of lipid derived volatiles in red fruit,
auxin activated lines accumulated some apocarotenoid and phenylpropanoid volatiles. A combined analysis of the volatile profiles
indicated that tomato ripening mutants rin and hp are affected in volatile production in a way that resembles that of asDELLA fruits,
while fruits from IAA9 RNAi lines are more like nor and cnr mutants in terms of volatile profiles. The effect of GA or IAA on ripening
was not a general effect but only on some specific aspects, as it can be deduced from volatile, primary metabolism and transcript
profiling, and suggests new ways to modulate these aspects of ripening.
Email Address for correspondence: jrambla@ibmcp.upv.es
Cell wall polymer composition of tomato fruit changes during development and pectin levels are reduced in Rab11a
antisense fruit (Poster)
Daniel Lunn (University of Nottingham, United Kingdom), Thanh D Phan (University of Nottingham, United Kingdom), Tucker A
Gregory (University of Nottingham, United Kingdom), Grantley W Lycett (University of Nottingham, United Kingdom)
During development and ripening of tomato fruit changes in the cell wall occur that ultimately contribute to softening. Cell wall
materials, and enzymes involved in their metabolism, are secreted to the cell wall and we have shown previously that antisense
inhibition of the SlRab11a GTPase interferes with this secretion and reduces the rate of fruit softening (Lu et al., 2001, Plant Cell,
13, 1819-1833). In this study, we have used quantitative real time PCR to show that the SiRab11a gene was expressed mainly in
expanding green fruit yet impacted on the texture of ripe fruit. Vesicle trafficking is involved in the transport of pectin and
hemicellulose from the Golgi apparatus to the cell wall, and also in the trafficking of cellulose synthase to the plasma membrane.
We have thus investigated possible differences in cell wall composition, during development, between the wild type and the
antisense fruit. We saw marked differences in the cell wall composition, with pectin levels peaking later and at a lower level in the
Rab antisense fruit. This implies that this particular Rab GTPase might preferentially regulate trafficking of vesicles carrying pectin
cargoes. It also indicates that alteration of cell wall composition, rather than of enzyme secretion may offer an alternative approach
to extension of shelf life.
Email Address for correspondence: sbxdl@nottingham.ac.uk
Characterization of two new “pink /y”-like fruit skin mutants in tomato (possible talk)
Josefina-Patricia Fernandez-Moreno (CSIC-IBMCP, Spain), Shelly Ben-Havivi (Weizmann Institute of Sciences, Israel), Justin
Lashbrooke (Weizmann Institute of Sciences, Israel), Oren Tzfadia (Weizmann Institute of Sciences, Israel), Ilana Rogachev
(Weizmann Institute of Sciences, Israel), Sagit Meir (Weizmann Institute of Sciences, Israel), Tohru Ariizumi (University of Tsukuba
Gene Research Center, Japan), Antonio Granell (CSIC-IBMCP, Spain), Asaph Aharoni (Weizmann Institute of Sciences, Israel)
The phenylpropanoids represent a diverse group of secondary metabolites, some of them possessing health-promoting properties.
Nowadays, such metabolites are acquiring high importance in the quality improvement of the tomato fleshy fruit. In a previous study
we provided evidence that SlMYB12, a MYB type Transcription Factor, serves as a main regulator of the phenylpropanoid pathway
in tomato fruit, more specifically of its flavonoid branch. It was suggested that a mutation inSlMYB12,called “pink” (or “y”), results in
altered phenylpropanoid accumulation. The most pronounced phenotype of “y” is the pink color of the fruit skin due to the lack of
the yellow pigmented flavonoid, naringenin chalcone. Two different “pink/ y”-like EMS mutants, calledylike1andylike2, were
identified in the TOMA-TOMA mutant collection (cv. Micro-Tom; http://tomatoma.nbrp.jp/indexAction.do). These mutants were
subjected to detailed characterization, primarily, through comprehensive metabolite profiling. Both mutants were affected in fruit
flavonoid biosynthesis. However, detailed analysis revealed dramatic differences in flavonols and specific phenylpropanoid
precursors which were not affected in the “y” mutant reported earlier. The molecular bases underlying these two new pink fruit
mutants are currently under investigation.
Email Address for correspondence: jofermo7@upvnet.upv.es
Cucurbita pepo mutant collection: mutations observed in reproductive and vegetative development which prevented fruit
set. (poster)
Nelly Vicente-Dólera (IFAPA Centro la Mojonera, Spain), Teresa Pomares-Viciana (IFAPA Centro La Mojonera, Spain), Manuel
Moya (IFAPA Centro La Mojonera, Spain), Pedro Gómez (IFAPA Centro La Mojonera, Spain)
Induced genetic variation of crops through methods of reverse genetics has been integrated into breeding allowing the identification
of important regulators of fruit development and ripening. Nowadays amutant collection resource for squash has been generated by
ethyl methanesulfonate (EMS) mutagenesis and is available for mutation breeding. The cultivar MU-CU16, morphotype zucchini,
was chosen as the genetic background for the initial Cucurbita pepo mutant population. About 4200 seeds were treated with EMS
40 mM giving as a result 2000 M2 mutant lines. One of the main critical aspects in the development of this mutant population has
been the fertility decrease because approximately 50% of the population did not produce fruit. Visual mutationswere evaluated
trying to determine how mutations altered reproductive development and verifying if a significant presence of them prevented
correct fruit set in M1 generation. Most mutations affected vegetative growth resulted from modifications in the normal architecture
of the plant, starting at the vegetative level with changes in leaves or in general plant architecture. All of them preventing correct
flower formation andtherefore fruit set. High variability was corroborated in specific mutants that change flower development; most
common were mutations of morphology of floral organs in both floral types. Female flowers showed changes in one or more
verticiles at the same time and altering petals, stigma and ovary. Male flowers were altered in a similar way, also displaying
changes in petals.
Email Address for correspondence: nelly.vicente@juntadeandalucia.es
Development of parthenocarpic fruits in the pear (Pyrus communis) cultivar Conference (Possible talk)
Muriel Quinet (Université catholique de Louvain, Belgium), Anne-Laure Jacquemart (Université catholique de Louvain, Belgium)
Pear is the second fruit production in Belgium and the cultivar Conference represents 90% of this production. Pyrus communis is a
self-incompatible species and requires inter-cultivar cross-pollination to develop fruits. However, blooming occurs early in the
Spring and climatically unfavorable spring conditions (frost, low temperatures, rain,…) could prevent the pollination by insects. In
this case, parthenocarpy induction by spraying plant hormones, mainly gibberellins, is a common practice in orchards and allows
achieving sufficient yield. No precise study has been carried out to determine the most efficient hormones, the best application time
and the required amounts to apply. Our work aims at highlighting pear tree reproduction and focuses on parthenocarpy processes
in the Conference cultivar. We investigated if intrinsic parthenocarpy due to endogenous hormones occured in Conference. We
also compared the efficiency of gibberellins, auxins and cytokinins in the parthenocarpic fruit induction. Parthenocarpic fruit
development was compared to fertilized fruits resulting from hand compatible cross-pollination. Spontaneous intrinsic
parthenocarpy occurred in Conference, but pollen deposit (even incompatible) increased the number of fruits initiated. Gibberellins
(GA3) increased the fruit set compared to the other hormonal treatments and trees treated with gibberellins and/or cytokinins
produced larger fruits. Parthenocarpic fruits remained, nevertheless, smaller than fertilized ones. Gibberellin inhibitor treatments
showed that endogenous gibberellins do not act alone to induce parthenocarpy and polyamines quantification revealed a role for
putrescine and spermine in parthenocarpy induction in Conference.
Email Address for correspondence: muriel.quinet@uclouvain.be
Epigenetic analysis of wild tomato species (poster)
Emeline Teyssier (Université de Bordeaux, France), Massimo Rainieri (ENS Paris, France), Boureau Lisa (Université de Bordeaux,
France), Linda Stammitti-Bert (Universit驩 de Bordeaux, France), Anne Bertrand (Université de Bordeaux, France), Alain Rival
(IRD, France), Giovanni Bernacchia (Universita di Ferrara, Italy), Philippe Gallusci (Université de Bordeaux, France)
Tomato (Solanum lycopersicum) which forms a small monophyletic clade within the large Solanaceae family has been chosen as a
model system for studying the Solanaceae genome, as well as fruit development and ripening, and crop domestication. Though
many efforts have been devoted to the analysis of the genetic diversity of tomato species, little work has focused on the epigenetic
diversity in this clade, although there is a general agreement that epigenetic processes play essential role in the phenotypic
diversity in animal and plant system. The present project is aimed at analyzing the epigenetic diversity in a subset of wild tomato
species. The Solanum lycopersicum clade presents a favorable situation for such a study as it is constituted of diploid plants
sharing a high degree of genomic syntheny. This study was focused on tomato Polycomb group genes of the Enhancer of Zeste
family, which consists in three genes (SlEZ1, SlEZ2, SlEZ3). SlEZ1 and SlEZ2 genes were previously shown to be involved in the
control of fruit and flower development of the domesticated tomato (How Kit A et al, 2010), whereas the role of SlEZ3 remains
unknown. Our analysis includes the comparative analysis of SlE(Z) gene sequences, as well as the study of their expression during
tomato fruit development. Interestingly the analysis of SlEZ2 gene in red-fruited species compared to green-fruited species
revealed major differences in fruit DNA methylation and gene expression profiles. These differences were correlated with the
presence of a retrotransposon in the SlEZ2 promoter region in red-fruited species specifically.
Email Address for correspondence: eteyssie@bordeaux.inra.fr
Epigenetic control of tomato fruit development (Invited)
Phillipe Gallusci (Bordeaux University, France), Lisa Boureau (Bordeaux University, France), Anne Pribat (INRA, France), Anne
Bertrand (Bordeaux University, France), Linda Stammitti (Bordeaux University, France), Emeline Teyssier (Bordeaux University,
France)
Epigenetic modifications include DNA methylation and numerous posttranslational modifications of histones. Recent discoveries
have shown that fruit development not only rely on hormones and genetic factors, but also depend on the epigenetic architecture of
the genome that determine gene expression pattern.
Over the last years we have analysed the function the Poplycomb group proteins that impose a repressive histone mark at specific
loci. In the model plantArabidopsis thalianathe Polycomb Repressive Complex 2 (PRC2) is involved in the epigenetic regulation of
various aspect of plant development. Proteins which contribute to the PRC2 are encoded by members of three distinct gene
families, namelyEnhancer of ZesteorE(z),Suppressor of Zeste 12[Su(z)1] andExtra Sex Combsor [ESC]. We have demonstrated
that tomato E(z) proteins are encoded by three genes (SlEz1,SlEz2andSlEz3) that present specific expression pattern intomato. In
contrast the tomato Su(z)12 protein, SlEMF2, and the ESC proteins, SlFIE, are encoded by unique genes that are ubiquitously
expressed in this plant. RNAi lines have been generated in order to analyse the function of these different genes. Our results are
consistent with the existence of at least two different PRC2 complexes in tomato that play important roles in the control of leaf,
flower and fruit development.
In addition, we have initiated the analysis of the role of DNA methylation in fruits. Plants knocked down for genes involved in the
control of DNA methylation, present numerous phenotypes that are likely to occur following the generation of silenced epialles.
Email Address for correspondence: philippe.gallusci@bordeaux.inra.fr
Fruit Development in Opium Poppy and the Evolution of Fruit Form (possible talk)
Sofia Kourmpetli (University of Leicester, United Kingdom), Philip Hands (University of Leicester, United Kingdom), Donna Sharples
(University of Leicester, United Kingdom), Sinéad Drea (University of Leicester, United Kingdom)
Opium poppy (Papaver somniferum) is globally renowned for its pharmacological relevance. Its opiate-rich large capsular fruit is a
product of long domestication breeding programmes with a focus on capsule size, seed retention and increased alkaloid content.
Much of the work investigating the genetic basis of fruit development has been done in core eudicot species, such as Arabidopsis,
Brassica and tomato, though several groups have adapted genetic tools for more basal plant species. As a member of the
Papaveraceae family, within the Ranunculales order, opium poppy is a basal eudicot. Moreover, there is also extensive
morphological diversity within the somniferum species in terms of fruit form. We are using P. somniferum as a model to shed light
on fruit development in basal eudicots and the evolution of genetically controlled traits related to fruit form. Using an RNAseq
approach, we identified a number of poppy genes that are expressed throughout fruit development, including members of the
MADS-box and YABBY gene families. Gene expression and functional analyses are being undertaken in poppy in order to fully
characterise these genes; in addition to complementation studies in corresponding Arabidopsis backgrounds. These analyses will
help determine the extent of gene conservation or diversification in basal species with distinctive fruit forms.
Email Address for correspondence: sk425@le.ac.uk
Genetic and molecular characterization of the fruit indeterminate growth (fig), a new tomato mutant altered in gynoecium
development (poster)
Laura Castañeda (Centro de Investigación en Biotecnolog᳭a Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain),
Fernando Pérez-Martn (Centro de Investigación en Biotecnología Agroalimentaria (BITAL). Universidad de Almer㭭a. CeiA3.,
Spain), Estela Giménez (Centro de Investigación en Biotecnolog鳭a Agroalimentaria (BITAL). Universidad de Almería. CeiA3.,
Spain), Juan Capel (Centro de Investigación en Biotecnologa Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain),
Sibilla Sánchez (Instituto de Biologa Molecular y Celular de Plantas (UPV-CSIC)., Spain), Vicente Moreno (Instituto de Biología
Molecular y Celular de Plantas (UPV-CSIC)., Spain), Trinidad Angosto (Centro de Investigación en Biotecnologa Agroalimentaria
(BITAL). Universidad de Almería. CeiA3., Spain), Rafael Lozano (Centro de Investigación en Biotecnologa Agroalimentaria
(BITAL). Universidad de Almería. CeiA3., Spain)
A collection of T-DNA mutant lines was generated in tomato (Solanum lycopersicum L.) with the aim to isolate new regulators of
reproductive development in this model species. Thus, the 989ET73 line was selected because of the abnormal development of
fruit-like structures inside the main fruit, a feature that is repeated in an indeterminate manner, as well as alterations in the size and
shape of columella and locules. Despite the fruit indeterminate growth (fig) phenotype of the mutant fruits, they were fertile and
ripened normally. Phenotypic analysis also revealed an increased size of gynoecium and high number of fused styles and stigmas
developed by mutant flowers, which was in accordance with the cell identity changes observed by scanning electronic microscopy.
The fig mutant phenotype is inherited as monogenic and recessive although co-segregation analysis suggested that this was likely
due to a somaclonal variation as no correlation phenotype-T-DNA insertion was detected. Similar phenotypes have previously been
observed in silencing lines of carpel identity gene TAG1 and SlDELLA gene, a repressor of the gibberellin signaling pathway,
suggesting a putative interaction of the FIG gene with these regulatory pathways. Expression analysis of regulatory genes involved
in fruit development, gibberellin biosynthesis and meristem activity were carried out. Preliminary results support that a new factor
involved in carpel development and determinacy may be responsible for the fig mutant phenotype. Genetic and genomic
approaches currently in progress, and positional cloning of the mutated gene, will allow for the elucidation of the functional role of
FIG gene during reproductive development of tomato.
Email Address for correspondence: ccl126@ual.es
Genomic approaches to unravel and reconstitute volatile production in fruit
Antonio Granell (IBMCP, Spain) (invited)
Volatile compounds are produced by fruits as a strategy to attract seed-dispersers and therefore they contribute to fruit organoleptic
quality. Variability in the volatile chemical composition is responsible for the wide variety of aroma and flavor exhibited by fruits.
Despite of that modern breeding has resulted in fruit with low volatile profile and therefore low organoleptic quality. A combination of
different strategies including QTL mapping, candidate gene and biochemical approaches has produced a wealth of information on
the genetics and molecular mechanisms of fruit volatile production and as a consequence we are starting to use volatile
composition in the fruit quality breeding programs. We have been using recombinant inbred and introgression lines representing the
whole genome of selected wild relatives in cultivated tomatoes and segregating populations of strawberry and peach to identify
volatile QTLs. Our results revealed novel vol QTLs some conserved across species and some confirmed in derived ILs for specific
volatiles. We have also been using a combination of other genomic approaches such as differential gene expression of lines with
extreme levels for specific volatiles to identify candidate genes in volatile production or metabolism. Although some of the QTLs
colocalize in genes involved in volatile production this is not always the case and some may be involved in volatile metabolism by
conjugation to produce compounds which are either non-volatile or have different odor-threshold or attributes, indicating that
particularly methylation or glycosilation are important for volatile variability.
email: agranell@ibmcp.upv.es
Email Address for correspondence: agranell@ibmcp.upv.es
Grape berry development and ripening (invited)
Serge Delrot (University of Bordeaux, France), Le Guan (Institute of Botany Beijing, China), Zhan Wu Dai (INRA Bordeaux,
France), Ben-Hong Wu (Institute of Botany Beijing, China), Virginie Lauvergeat (University of Bordeaux, France), Eric Gomes
(University of Bordeaux, France), Shao-hua Li (Institute of Botany Beijing, China), Francisca Godoy (Univ. Pontif. Santiago, Chile),
Nathalie Kuhn (Univ. Pontif. Santiago, Chile), Patricio Arce-Johnson (Univ. Pontif. Santiago, Chile)
Grapevine (Vitis viniferaL.) is a non climacteric fruit species used as table fruit, dried raisins, and for vinification (wines) and
distillation (liquors). The optimal properties expected from table and wine grape at maturity significantly differ in terms of yield,
sugar content, skin structure, seeds and tannins. These differences may be assessed with multivariate analysis by gathering
various published data in both table and wine grapes. The review will summarize recent data related to the molecular and hormonal
control of grape berry development and ripening, with special emphasis on secondary metabolism and response to the
environment.
Email Address for correspondence: serge.delrot@bordeaux.inra.fr
Influence of ascorbate-recycling, light and temperature during ripening on tomato fruit ascorbate content. (poster)
Helene Gautier (INRA, France), Capucine Massot (INRA, France), Vincent Truffault (INRA, France), Doriane Bancel (INRA,
France), Rebecca Stevens (INRA, France)
Understanding how light and temperature affect fruit ascorbate (AsA) content is a great challenge to improve fruit nutritional quality.
Therefore, cherry tomato fruit harvested at breaker stage were placed under different temperatures (12°C, 23аC and 31°C) and
irradiance regimes (darkness or 150 еmol m-2 s-1 ) for 56h. Changes in AsA metabolism were characterized from ascorbate and
glutathione content, enzymic activities related to oxidative stress and AsA/glutathione cycle and the expression of genes coding for
the 5 last enzymes of AsA biosynthesis pathway. Light increased AsA content in fruit pericarp up to 67% at 12°C, but had no effect
on AsA content at 31аC, confirming their interaction and the important role of fruit microclimate to regulate fruit AsA content. At any
temperature tested, light enhanced the expression of genes coding for AsA biosynthesis, but at 12°C, light upregulated a higher
amount of genes compared to 23 or 31аC. At 31°C, light did not trigger any promotion of AsA pool despite increased transcripts
level of gene coding for enzymes of AsA biosynthesis pathway. This might be related to a lower recycling of AsA. Indeed, at 31аC,
the activities of monodehydroascorbate reductase (MDHAR) and glutathione reductase were significantly reduced under light,
indicating that enzymes of the ascorbate / glutathione cycle may be limiting to recycle AsA. Transgenic lines silenced for an
MDHAR gene have been generated and tested under similar environmental conditions. Results are discussed and shed light on the
stability of the ascobate pool in fruits under different environmental conditions.
Email Address for correspondence: helene.gautier@avignon.inra.fr
Influence of drought on tomato fruit histology (poster)
Ilinka M Pecinar (Faculty of Agriculture, Serbia and Montenegro), Sofija V Pekic Quarrie (Faculty of Agriculture, Serbia and
Montenegro), Dragana V Rancic (Faculty of Agriculture, Serbia and Montenegro), Maja B Terzic (Faculty of Agriculture, Serbia and
Montenegro), Radenko J Radosevic (Faculty of Agriculture, Serbia and Montenegro), Radmila I Stikic (Faculty of Agriculture,
Serbia and Montenegro), Nadia Bertin (INRA Plantes et systèmes de culture horticoles, France)
It is well known that water reduction limits fruit growth rate and final weight of tomato. These effects depend on the degree and
duration of water restriction. Moreover the same volume of water supplied at different stages of development produces different
effects on fruit size. Water deficit effects differentiation of reproductive tissue either through “cell-division effect” or through “cell
size-effect”. The final fruit cell number and size can vary several folds depending on environmental conditions, such as water
supply. The objective of the present study was to determine the effect of different irrigation practices (PRD and DI) on tomato fruit
histology during fruit development. We specifically investigated water deficit effects on pericarp cell size, pericarp
cell number and size of different pericarp cell layers in young and mature fruit. Our study was performed on two genotypes: wild
type Ailsa Craig and its ABA deficient flacca mutant. In optimal water conditions fruits of flacca mutants are smaller compared to
wild type, due to a reduction in cell size but not in cell number. Under water deficit, fruit growth of both flacca and wild type is
reduced. The study of drought effects on fruit histology and cytology are in progress and will bring new knowledge to understand
the effects of water deficit on fruit development in relation to ABA synthesis.
Email Address for correspondence: ilinka@agrif.bg.ac.rs
Inmuno-histochemical analysis of pectin matrix modificationsdue to polygalacturonase down-regulation in strawberry
fruit tissues (poster)
Sara Pose Albacete (Universidad de Málaga, Spain), Manuel Cifuentes (Universidad de Málaga, Spain), Miguel Angel Quesada
(Universidad de Mᡡlaga, Spain), Jose Angel Mercado (Instituto de Hortifruticultura Subtropical y Mediterránea, Spain)
Transgenic strawberry plants expressing an antisense sequence of a fruit specific polygalacturonase gene had previously been
obtained [1]. Transgenic ripe fruits were firmer than wild types and this textural change was related to the presence of higher pectin
contents in the cell wall [1]. In this work, an inmuno-histochemical analysis using several cell wall antibodies in strawberry ripe fruit
tissues from PG down-regulated transgenic plants has been performed. In situ inmuno-histochemical protocol was optimized by
minimum washing and isolated incubation steps, using different antibodies in different slides. This last strategy effectively
disminished solubilization and aggregation of pectic epitopes during the process. Transgenic fruit sections showed better tissue
organization and integrity than control. The homogalacturonan specific antibodies (LM19 and LM20) yielded more intense signals
on epidermis and cortex from transgenic tissues than on wild type. Demethylated homogalacturonan is the target of
polygalacturonase, so these results could be directly related to PG down-regulation. Besides, LM5 and LM6 (antibodies which
recognize 1,4-β-D-Gal and 1,5-α-L-Ara, respectively) also showed higher signal intensity on transgenic than control lines. As
explanation, we propose a side effect of PG silencing due to the interconnection between homogalacturonan and
rhamnogalacturonan domain in cell walls. Regarding LM15 signal which recognizes xyloglucan epitopes, no differences were
observed between transgenics and control line. Summarizing, the in situ alterations observed on pectin matrix in transgenic fruits
with enhanced tissue integrity support the key role of pectins in fruit texture.
[1] Quesada et al.(2009) Plant Physiology.150, 1022-1032
Email Address for correspondence: sarapose@uma.es
Leaves, culm and structural elements of the ear provide kernel development and ripening in barley by photosynthates and
remobilized carbohydrates (poster)
Irina S Kiselyova (U, Russia)
The highest rate of photosynthesis in spring barley (Hordeum vulgare L., cv. Varde) was observed during the vegetative growth.
Assimilates synthesized at that period were used for growth and development of leaves, culm and structural ear elements (rachis,
glumes, awns) and for the temporal deposition in the stem. Since the beginning of the kernel formation when their request for
assimilates was supported by the current leaf photosynthesis, part of assimilates were deposed as transitory and structural
polysaccharides in temporary sinks - culm and structural elements of the ear.
The data on growth rate, biomass accumulation in barley organs, concentration of different carbohydrate fractions in them and the
character of utilization and reutilization of 14 C-compounds during plant development indicated on secondary mobilization of fructan,
pectin and hemicellulose fractions in lower culm internodes and structural elements of the ear. The contribution of different barley
organs in the formation and maturation of the kernels and the rate of the remobilization of assimilates synthesized by plants before
flowering depended of the climatic conditions of the vegetation season and the duration of photosynthesis. Such plasticity of the
sink-source system allows plants to adapt their life cycle to changing environmental conditions.
Email Address for correspondence: Irina.Kiselyova@usu.ru
Multi-hormonal control of the transcriptional regulation associated with fruit development and ripening. (Invited)
Mondher Bouzayen (INRAINP-ENSA Toulouse, France)
Fruit development and ripening rely on a series of developmental transitions that lead to major metabolic reorientation and
structural changes. These shifts are are coordinated by a complex network of interacting genes and signalling pathways. In the
case of fleshy fruit, while the co-ordinated changes in the levels of several plant hormones during fruit growth strongly suggest their
dynamic involvement in this process, it is likely that their coordination is a matter of a multi-hormonal control. Combined genomewide transcriptomic profiling and reverse genetics approaches were applied to investigate the molecular events underlying tomato
fruit development and ripening. The data emphasize the role of auxin and ethylene-dependent transcriptional control as part of the
mechanisms by which the fruit developmental program switches from a flower organ to differentiated fruit and later on into a
ripening process. A number of ERF (Ethylene Response Factors) genes display an auxin-dependent regulation whereas some
members of the ARF (Auxin Response Factors) and Aux/IAA families showed clear regulation by ethylene. Down-regulation of
some ARFs resulted in ripening phenotypes and likewise, some ERF genes were shown to impact ethylene-regulated ripening
aspects. Overall, the data shed new light on some of the molecular players involved in the cross-talk between auxin and ethylene
supporting the idea that ERFs are part of an intricate web of regulation in which multiple transcription factors are competing for
promoters to control the expression of genes that are essential for a wide range of plant responses to ethylene.
Email Address for correspondence: bouzayen@ensat.fr
Peeling Apart the Structure, Functions and Diversity of Fruit Cuticles
Jocelyn K Rose (Cornell University, United States) (possible talk)
The plant cuticle, a lipid rich hydrophobic layer that covers all aerial organs, forms the outermost barrier between a plant and its
environment. As such, it provides the primary line of defense against pathogens, plays a critical role in restricting water loss and
protects plants from a range of other abiotic stresses. Moreover, the cuticle has been shown to be an important factor in regulating
organ development and integrity. However, much remains to be learnt about cuticle biosynthesis, particularly with regard to
trafficking, assembly,restructuring and interactions with polysaccharide cell wall components, and the functional significance of
those features. Tomato (Solanum lycopersicum) fruits offer an excellent experimental system to investigate such phenomena as,
unlike the cuticles of other experimental model plants such as Arabidopsis, those of tomato fruits are extremely thick and
astomatous, providing a pore-less uniform material that is relatively easy to isolate and manipulate. We have been developing a
multi-pronged strategy to evaluate fruit cuticle structures and functions, including the development of new imaging tools, the
characterization of cuticles from tomato mutants and wild species, and the use of cell type-specific RNA-Seq transcriptome and
proteome profiling. Data generated through this ‘systems’ approach has shed light on various previously unsuspected functional
roles of specific cuticle components, as well as the remarkable structural and biochemical diversity of tomato cuticles across
different genotypes. We have also gained insights into mechanisms of cuticle assembly and remodeling, as well as their
evolutionary origins.
Email Address for correspondence: jr286@cornell.edu
Regulation of tomato fruit ripening: genes, genome, epigenome. (invited)
James Giovannoni (Boyce Thompson Institute for Plant Research, United States)
Tomato is one of the most studied species for fleshy fruit development and climacteric ripening. Availability of a high quality tomato
genome sequence has facilitated genetic inquiries via approaches that were not possible until now. Advances in understanding the
genetic regulation of tomato fruit ripening to date have focused mostly on characterization of genes and gene expression patterns
associated with ripening. Identification of specific genes underlying ethylene biosynthesis and downstream ethylene responses,
cell wall metabolism and carotenoid accumulation have been more recently complemented with insights into transcriptional control
through the work of numerous laboratories. Ripening transcription factors include those encoded by the RIN-MADS and CNR-SPL
genes underlying the rin and Cnr mutations, respectively, and which completely block ripening. We have recently identified a
number of additional transcription factors regulating fruit development and ripening and are building a network of regulatory control.
In at least the case of RIN-MADS, transcription control intersects with changes in the epigenome. Exploring the epigenome during
fruit development we see changes in promoter methylation that parallel ripening phenomena. At least some of these changes are
associated with sites that bind important ripening regulators. In summary we provide evidence suggesting that both genetic and
epigenetic factors regulate fruit development and ripening phenomena.
Email Address for correspondence: jjg33@cornell.edu
Respiration and ATP synthesis in tomato fruit chromoplasts during ripening (possible talk)
Marta Renato (Department of Plant Biology (University of Barcelona), Spain), Albert Boronat (Center for Research in Agricultural
Genomics (University of Barcelona), Spain), Joaquim Azcón-Bieto (Department of Plant Biology (University of Barcelona), Spain)
During tomato fruit ripening, chloroplasts differentiate into chromoplasts losing their photosynthetic machinery and synthesizing
large amounts of carotenoids. Chromoplasts present a membrane-bound electron transport chain ending in O2 uptake activity,
known as chromorespiration, a process which is not well understood. In this work, respiratory assays with isolated chromoplasts
from tomato fruit were conducted. The results show that this O2 uptake activity is stimulated by the electron donors NADH/NADPH
and is sensitive to octyl gallate (an inhibitor of the Plastidial Terminal Oxidase, PTOX). It also responds to the uncoupler
carbonylcyanide m-chlorophenylhydrazone (CCCP), indicating the presence of a H+ -gradient across chromoplast membranes. The
ATP synthesis rates of isolated tomato chromoplasts were quantified, and the results indicate that this activity is dependent on
NAD(P)H and is sensitive to both octyl gallate and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB), an inhibitor of
cytochrome b6 fcomplex. To analyze the significance of chromoplast respiration in the context of total tissue dark respiration, we
studied the effect of octyl gallate in oxygen uptake and ATP levels of tomato pericarp tissue at different ripening stages. Data
suggest that chromorespiration increases over the course of ripening, is responsible of about 26% of total oxygen consumption in
ripe tomato tissue and may represent a relevant contribution to ATP content in red fruit. In contrast, the number of active
mitochondria in tomato tissue was found to decrease throughout ripening.
Email Address for correspondence: mrenato@ub.edu
Role of FaBG3 in fruit development and ripening of strawberry (possible talk)
Qian Li (College of Agronomy and Biotechnology China Agricultural University, China), Kai Ji (College of Agronomy and
Biotechnology China Agricultural University, China), Shengjie Dai (College of Agronomy and Biotechnology China Agricultural
University, China), Pei Chen (College of Agronomy and Biotechnology China Agricultural University, China), Yufei Sun (College of
Agronomy and Biotechnology China Agricultural University, China), Yanping Wang (College of Agronomy and Biotechnology China
Agricultural University, China), Chaorui Duan (College of Agronomy and Biotechnology China Agricultural University, China), Yan
Wu (College of Agronomy and Biotechnology China Agricultural University, China), Hao Luo (College of Agronomy and
Biotechnology China Agricultural University, China), Ya Wang (College of Agronomy and Biotechnology China Agricultural
University, China), Yangdong Guo (College of Agronomy and Biotechnology China Agricultural University, China), Ping Leng
(College of Agronomy and Biotechnology China Agricultural University, China)
Abscisic acid (ABA) levels are regulated by its biosynthesis, catabolism and reactivation. β-Glucosidase is believed to take part in
adjusting ABA content via hydrolysis of ABA glucose ester (ABA-GE) to release active ABA. However, it lacks evidence for the role
of β-glucosidase genes in adjusting the ABA level during fruit ripening. To investigate the contribution of FaBGs in fruit, eight
Fa/FvBG genes encoding β-glucosidase were isolated from the strawberry nucleotide database of GenBank. The cDNA and
deduced amino acid sequences of these genes showed high similarity to their homologous genes in other plants. Real-time PCR
analysis revealed that the ABA content was not only regulated by FaNCED2 and FaCYP707A1, but also regulated by Fa/FvBG
genes at transcriptional level during fruit development, in response to ABA application and dehydration. Among the Fa/FvBG
genes, expression of FaBG3 was the highest, showing peaks at the ripening stage. To verify the role of this gene, we suppressed
expression of FaBG3 via virus induced gene silencing (VIGS). FaBG3-RNAi fruits in which the expression of FaBG3 was downregulated markedly did not show full ripeness, and its ABA content was 42% of the control. In all the fruits, the expressions of
FaNCED2, FaCYP707A1 and all FaBGs were up-regulated 6 days after inoculation. Ethylene release and expression of FaACS1,
FaACO2 and FaETR2 in FaBG3-RNAi fruit were higher than those of the control fruit. These results indicate that FaBG3 plays an
important role in fruit ripening via modulation of the ABA level of strawberries.
Email Address for correspondence: woshiliqian0204@126.com
Secondary metabolism during fruit ripening (invited)
Alisdair R Fernie (MPI of Molecular Plant Physiology, Germany), Takayuki Tohge (MPI of Molecular Plant Physiology, Germany),
Saleh Alseekh (MPI of Molecular Plant Physiology, Germany)
Fruit development and maturation are well understood from a hormornal-regulatory point of view, as well as in terms of cell
expansion and development changes in cell wall biosynthesis and pigmentation. Furthermore, several of metabolite and
transcriptome profiling experiments revealed shifts in the abundance of both primary and secondary metabolites, such as sugars,
organic acids, volatiles, polyphenolics and acyl-glycosides, during fruit ripening in several model plant species. In an effort of
improvement dietary antioxidant content of model crop species, carotenoids and polyphenolics have been a major focus for
research of metabolic engineering in fruits. In contrast to the complexity of biosynthetic regulation of the primary metabolism
network. Much of secondary metabolism is directly controlled by transcription factors which can regulate nearly all members of
biosynthetic genes of in a concerted manner. However since secondary metabolism is induced by several environmental factors
such as biotic, high light, senescence, water and nutrient deficient conditions, the relationship between fruit ripening event and fruit
specific regulation network of secondary metabolism is unclear at present. In this talk, shifts in the abundance of secondary
metabolites during fruit ripening in model plant species is focused and discussed with primary metabolite and transcript profiling
during fruit ripening stages. Attention will also be paid to genotypic variance in these pathways in fruit via a survey of secondary
metabolite in wild species.
Email Address for correspondence: fernie@mpimp-golm.mg.de
Structural features of legume fruits in relation to the problem of self-incompatibility (poster)
Svetlana A Zimnitskaya (Ural federal University, Russia)
In legumes the effectiveness of fruit formation depends on the number of seeds in pods and their quality. Embryological study of 32
species of legumes in the Urals revealed the limiting factors of fruit formation. It was found that the system of pollination played an
essential role among others. In some entomophilies a simultaneous combination of structural and functional features promoting
both cross-and self-pollination was found. The species that can change the type of cross-pollination to autogamous in the absence
of pollinators, in senescing flowers, unfavorable weather conditions or on the edge of the area are of a particular interest. The
presence of multi-component system of pollination increased apparently fruit formation efficiency.Using light, fluorescent and
electron microscopy the structure and development of the flower in species with multi-component system of pollination was studied.
Structural and functional prerequisites for the changes in pollination system and self-incompatibility gametophyte system during
pollen germination and pollen tube growth were detected. Is self-fertilization effective, can it be realized in the flower and does it
lead to the formation of the fruit? In the Urals in annual clover species, for example, it could be effective, but also the is a
predominant type of pollination. In perennial species it is realized after a quite long period of getting pollen on the stigma in the
senescing flower. Nevertheless, in some species, for example, white clover it leads to a mass fruiting.
Email Address for correspondence: zimn@list.ru
Study of Polyamines During Grape Ripening Indicate an Important Role of Polyamine Catabolism (possible talk)
Patricia Agudelo-Romero (University of Lisbon, Portugal), Cristina Bortolloti (University of Barcelona, Spain), Maria Salomé Pais
(University of Lisbon, Portugal), Antonio Tiburcio (University of Barcelona, Spain), Ana M Fortes (University of Lisbon, Portugal)
Grapevine (Vitis species) is the most economically important fruit crop worldwide. Ripening of non-climacteric fruits such as grapes
has been the subject of intense research. Despite this interest, little is known on the role played by polyamines in the onset of
ripening of non-climacteric fruits.
Molecular and biochemical studies were developed in three important Portuguese cultivars (Trincadeira, Touriga Nacional and
Aragonês) during the year 2008 and in Trincadeira during 2007. Transcriptomic studies revealed up-regulation of a gene coding for
arginine decarboxylase (ADC) during grape ripening in all the varieties. This increase was not accompanied by an increase in free
polyamines that presented a strong decrease. Furthermore, it was observed up-regulation of genes coding for diamine oxidase
(CuAO) and polyamine oxidase (PAO), together with a significant increase in their enzymatic activity.
In addition, ripening of Trincadeira grapes submitted to guazatine treatment, a potent inhibitor of polyamine oxidase activity, was
studied considering the transcriptional profiling complemented with biochemical data. The mRNA expression profile of harvest
stage (EL 38) was compared between mock and guazatine treatments using Affymetrix GrapeGen®. A total of 1880 unigenes were
differentially expressed between these samples.
Genes involved in amino acid, carbohydrate and water transport were up-regulated in mock treated samples suggesting that the
strong dehydrated phenotype obtained in guazatine treated samples may be due to impaired transport mechanisms. Moreover,
genes involved in terpenes᳭ metabolism were differentially expressed. Altogether, the results support an important role of
polyamine catabolism in grape ripening namely in cell expansion and aroma development.
Email Address for correspondence: agudeloromero@hotmail.com
Suppression of hmg1 gene affects the reproductive function of transgenic tobacco plants (poster)
Alexander A Ermoshin (Ural Federal University, Russia), Valeriya V Alekseeva (Branch of Institute of Bioorganic Chemistry,
Russia)
Isoprenoids are the largest class of plant metabolites involved in growth, development and the formation of reproductive organs.
The biosynthesis of these metabolites in cytoplasm is limited by the formation of mevalonic acid, which is encoded by the hmg1
gene. Usage of the strategy of antisense RNA can inhibit the formation of mevalonate and reduce the biosynthesis of isoprenoids in
plants.
Transgenic tobacco plants expressing the hmg1 gene in reverse orientation towards the constitutive viral promoter CaMV 35S were
obtained.
Pollen fertility decreased in transgenic lines more than 2-fold compared to control. The viable transgenic pollen began to grow on
the artificial medium later than in control plants. This phenomenon could be interesting for the approaches to reduction of crosspollination in wild and transgenic lines. The investigation of ovule (seed-bud) morphology in transgenic tobacco lines showed that
abnormal ovules occurred 1,5 times frequently in comparison with control plants. Thus, multiple pathologies in the development of
both male and female generative sphere under suppression of the biosynthesis of mevalonic acid in plants affected the quantity
and quality of seeds. The decrease in the seed capsules weight for 24-39% was found and a reduction in germination of transgenic
seeds was more than 20% that also reduces the environmental risks of transgenic plants.
The study was supported by The Ministry of education and science of Russian Federation, project 14.А18.21.0203.
Email Address for correspondence: bos_o@mail.ru
The tomato orange (tor) mutant represents a new allele of the Tangerine locus involved in tomato fruit ripening (poster)
Antonia Fernández-Lozano (Centro de Investigación en Biotecnolog᳭a Agroalimentaria (BITAL). Universidad de Almería. CeiA3.,
Spain), Beatríz Cara (Centro de Investigacin en Biotecnología Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain),
Fernando Prez-Martín (Centro de Investigación en Biotecnologa Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain),
Benito Pineda (Dpto. Biología del Desarrollo. Instituto de Biologa Molecular y Celular de Plantas (UPV-CSIC)., Spain), Vicente
Moreno (Dpto. Biología del Desarrollo. Instituto de Biología Molecular y Celular de Plantas (UPV-CSIC)., Spain), Trinidad Angosto
(Centro de Investigacin en Biotecnología Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain), Juan Capel (Centro de
Investigacin en Biotecnología Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain), Rafael Lozano (Centro de
Investigacin en Biotecnología Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain)
Carotenoid pigments are crucial for plant development as they contribute to light energy capture and protect from damages
produced by reactive oxygen species generated during photosynthesis. They also result important in human diet as part of the
antioxidant defense system. The carotenoid biosynthesis pathway has been well described but the genes regulating the different
biochemical steps remains to be characterized in detail. From the screening of tomato plants regenerated from tissue culture, a
recessive mutant with altered pigmentation, named as tomato orange (tor), was identified. The most remarkable traits of tor were
the orange color in flowers, roots, seeds and fruits as well as the yellowing of apical stems and leaves. Carotenoid analysis in ripe
fruits evidenced the accumulation of one main pigment whose absorbance spectrum matched with pro-lycopene. Given the
phenotypic similarity of the tor somaclonal mutant with tangerine, the CRTISO gene was sequenced in mutant plants and compared
to the wild-type tomato (cv. p73). This comparison revealed a deletion producing a frameshift mutation and therefore a truncated
protein. To validate the CRTISO loss of function in the tor mutant, a genetic complementation assay with tangerine was performed,
demonstrating that tor is a new allele of the Tangerine locus. To gain insight into the molecular function of CRTISO in tomato fruit
ripening, transcriptomic analysis of tor fruits was performed. An interesting profile of transcription factors was altered due to the
non-functional CRTISO as well as expected biological process such as response to stimulus, stress or defense response.
Email Address for correspondence: afl997@ual.es
The genetic control of fruit morphology in melon (invited)
Antonio J Monforte (IBMCP (UPV-CSIC), Spain), Belkacem Zarouri (IMIDRA, Spain), Jose M Alvarez (CITA, Spain), Jordi GarciaMas (CRAG( CSIC-IRTA-UB-UAB), Spain), Montserrat Martín (CRAG( CSIC-IRTA-UB-UAB), Spain), Mohamed Fergany (CRAG(
CSIC-IRTA-UB-UAB), Spain), Ana Caño (CRAG( CSIC-IRTA-UB-UAB), Spain), Aurora Daz (IBMCP (UPV-CSIC), Spain)
Wild melons produce oval/round fruits, however melon cultivars display a panoply of different fruit shapes and sizes, from round to
extremely elongated and from a few hundreds grams to several kilograms. Melon cultivars also differ in internal fruit morphology, as
the proportion of edible flesh, ranging from negligible in wild melons to the high flesh content of Occidental cultivars, and also seed
size and shape. During the last decade, we have developed a number of mapping populations in order to dissect the genetic
control of fruit quality traits in melon, such as fruit morphology. In the current presentation, we will review the results that we have
produced including genetic mapping, epistatic and genetic background interactions, heterosis, developmental studies, fine
mapping and candidate genes underlying the major melon fruit morphology loci.
Email Address for correspondence: amonforte@ibmcp.ibmcp.upv.es
The Molecular Control of Tomato Fruit Quality Traits: the Trade Off Between Visual Attributes, Shelf Life and Nutritional
Value (poster)
Sonia Osorio (University of Malaga, Spain), José G Vallarino (University of Malaga, Spain), Raphael T Carneiro (Cornell University,
United States), Anna Lytovchenko (Max-Planck-Institut für Molekulare Pflanzenphysiologie, Germany), Ryan McQuinn (Boyce
Thompson Institute for Plant Research, United States), James J Giovannoni (Boyce Thompson Institute for Plant Research, United
States), Alisdair R Fernie (Max-Planck-Institut f鼼r Molekulare Pflanzenphysiologie, Germany), Jocelyn KC Rose (Cornell
University, United States)
Tomato (Solanum lycopersicum) is an established model to study fleshy fruit development and ripening and is an important crop in
terms of its economic and nutritional value. Tomato fruit quality is a function of metabolite content which is prone to physiological
changes related to fruit development and ripening. It has been described some ripening tomato mutants, delayed fruit deterioration
(DFD), non-ripening (NOR) and ripening-inhibitor (RIN) which substantially extend “shelf life” in tomato for up to several months
when defined in terms of softening, water loss and resistance to postharvest biotic infection. However, it is not known whether this
extension in “shelf life” is in fact a desirable objective from the perspective of nutritional quality of the fruits. The aim of this work
was to use a metabolomics approach join to genomic tools to characterize compositional changes (sugars, amino acids, organic
acids and carotenoids) of non-softening tomato mutants reported (DFD, NOR and RIN) in comparison with the normally softening
fruits (Ailsa Craig and M82) during ripening and postharvest shelf-life. Important results related with ripening gene expression and
metabolic evolutions are shown.
Email Address for correspondence: sosorio@uma.es
The role of MADS-box genes in the evolution of seed dispersal strategies and fruit morphology (invited)
Cristina Ferrandiz (Instituto de Biologia Molecular y Celular de Plantas. CSIC-UPV, Spain), Chloe Fourquin (Instituto de Biologia
Molecular y Celular de Plantas. CSIC-UPV, Spain), Carolina Del Cerro (Instituto de Biologia Molecular y Celular de Plantas. CSIC-
UPV, Spain)
Fruits are a major evolutionary acquisition of Angiosperms, which protect the developing seeds and ensure seed dispersal. Fruits
show huge morphological and functional diversity, and, in addition, are of major economic importance, representing the edible part
of many crops and a source for secondary products. Our long-term goal is to understand how fruit patterning is established, and
what is the molecular basis of the diversity found between species.
A model explaining genetics of seed dispersal has been proposed in Arabidopsis, involving the MADS-box genes FRUITFULL
(FUL) and SHATTERPROOF (SHP). A key question we need to address is how well these genetic pathways are conserved among
the angiosperms, and how modifications on these routes have contributed to generate fruit morphological and functional diversity.
We have focused our studies on two eudicot families with dry dehiscent fruits. First, we have evaluated the functional conservation
of this genetic network in Nicotiana benthamiana, showing a conserved role of the SHP and FUL genes in controlling fruit
dehiscence, which strongly supports the ancestral role of this genetic network in late fruit development. Second, we have tested if
variations of this network can be related to morphological and functional fruit diversity in the Medicago genus, which presents a
range of fruit morphologies, from straight long pods to coiled and spiny fruits. All together, our data point to a key role of the
FUL/SHP genetic route in controlling pod morphology in Medicago, thus, unveiling the importance of the variation in this genetic
network to generate fruit diversity.
Email Address for correspondence: cferrandiz@ibmcp.upv.es
The tomato excessive number of floral organs (eno) mutation affects the genetic network underlying floral meristem
development (poster)
Antonia Fernández-Lozano (Centro de Investigación en Biotecnolog᳭a Agroalimentaria (BITAL). Universidad de Almería. CeiA3.,
Spain), Fernando J Yuste-Lisbona (Centro de Investigación en Biotecnologa Agroalimentaria (BITAL). Universidad de Almería.
CeiA3., Spain), Fernando Pérez-Martn (Centro de Investigación en Biotecnología Agroalimentaria (BITAL). Universidad de
Almer㭭a. CeiA3., Spain), Juan Capel (Centro de Investigación en Biotecnología Agroalimentaria (BITAL). Universidad de
Almer㭭a. CeiA3., Spain), Benito Pineda (Dpto. Biología del Desarrollo. Instituto de Biología Molecular y Celular de Plantas (UPVCSIC)., Spain), Vicente Moreno (Dpto. Biologa del Desarrollo. Instituto de Biología Molecular y Celular de Plantas (UPV-CSIC).,
Spain), Rafael Lozano (Centro de Investigación en Biotecnologa Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain),
Trinidad Angosto (Centro de Investigación en Biotecnologa Agroalimentaria (BITAL). Universidad de Almería. CeiA3., Spain)
The excessive number of floral organs (eno) mutant was identified in a phenotypic screening of a T-DNA mutant collection, as a
part of a systematic analysis devoted to the isolation of novel gene functions involved in reproductive development of tomato
(Solanum lycopersicum L.). Flowers developed by eno mutant plants showed an increased number of sepals, petals, stamens, and
carpels as compared to wild-type. The segregation observed in the T2 progeny was consistent with a monogenic recessive
inheritance of the eno mutation (χ2 =0.2; P=0.65). Southern blot analysis showed that original T1 line carried a single T-DNA
insertion, but it was not associated with the eno phenotype, which was also confirmed after evaluation of T3 progenies. Scanning
electron microscopy analysis revealed that eno mutation promotes a significant increase of the floral meristem size. Such
developmental change occurs at early stages of floral organogenesis, and should be responsible for the development of
supernumerary floral organs and larger multilocular fruits yielded by eno plants. This phenotype was similar to that showed by the
fasciated (fas) mutant; however, genetic complementation tests revealed that eno mutation was not allelic to the FAS locus, a key
determinant of evolutionary changes occurring during tomato domestication. Expression analyses of regulatory genes involved
either in carpel development or fruit size also suggest that we are facing a new mutation affecting the boundaries within the floral
meristem, which promote an increase of its size and consequently, the development of a higher number of floral organs.
Email Address for correspondence: afl997@ual.es
Transcription factors regulating carotenogenesis in apple (possible talk)
Charles Ampomah-Dwamena (Plant and Food Research, New Zealand), Nicky Driedonks (Radboud University, Netherlands),
David Lewis (Plant and Food Research, New Zealand), Andrew C Allan (Plant and Food Research, New Zealand)
Carotenogenesis is an important factor in fruit colour development and we are interested in establishing how the pathway is
regulated in apple (Malus x domestica). The phytoene synthase (PSY) enzyme is an important step in the carotenoid pathway,
functioning as a rate-limiting step to control pathway flux. In apple, 4 PSY genes are found on different linkage groups. To
understand how these genes are regulated, the apple PSY gene family was characterised by gene expression and promoter
analysis. Differences in gene expression patterns were observed for the apple PSYs in different tissues and developmental stages,
suggesting they are under different regulatory influences. Promoter sequence analysis by MatInspector identified MADS-box and
AP2 domain binding motifs in the regulatory regions. To further ascertain PSY interaction with these transcription factors (TFs), the
promoters were cloned by PCR into luciferase expression vector for in planta assay measuring interaction with cloned apple
transcription factor genes. We observed an up-regulation of these promoters by the MADS-box and AP2 domain containing genes
compared with other TF genes we tested, suggesting that MADS-box and AP2 domain containing proteins play important roles in
apple carotenogenesis through their interaction with PSY promoters.
Email Address for correspondence: charles.dwamena@plantandfood.co.nz
Transcriptome and Metabolome Analysis for Gene Discovery in the Steroidal Alkaloid Pathway (invited)
Asaph Aharoni (Weizmann Institute of Science, Israel)
Steroidal alkaloids (SAs) are common constituents of numerous plants belonging to the Solanaceae family. Solanine, a major SA in
potato was reported already 200 years ago and extensively studied as sprouting tubers may contain a relatively high content of SAs
that is potentially dangerous for human health .Consisting of a C27 cholestane skeleton composed of several heterocyclic rings and
nitrogen, SAs were suggested to be synthesized from cholesterol and further glycosylated to form steroidal glycoalkaloids (SGAs).
The early stages of SA biosynthesis, predicted to start from cholesterol up to the alkamine, were not investigated at the molecular
level although several possible pathways were suggested. Our main aim is to identify key genes in the biosynthesis of SGAs in the
Solaneceae family including in tomato fruit. We recently reported that silencing of the tomato GLYCOALKALOID METABOLISM 1
gene (GAME1), putatively encoding a glycoalkaloid- glycosyltransferase, resulted in up to 50% reduction in the principal tomato
SGA,α-tomatine. This study pointed to the importance of glycosylation in avoiding toxicity to the plant cell on one hand while
increasing toxicity to pathogens on the other. Through a combination of metabolic and transcript profiling we have identified a
different gene, GAME4, that appears to play a key role in the biosynthesis of the SGA aglycone from cholesterol in both potato and
tomato as its silencing resulted in a dramatic reduction of SGAs levels in tomato fruit. Results of experiments in which GAME4 and
Solaneaceae plants altered in its expression were characterized in detail will be presented.
Email Address for correspondence: asaph.aharoni@weizmann.ac.il
Understanding the interplay between epigenetic variation and gene regulatory networks during tomato fruit ripening.
(invited)
Graham B Seymour (University of Nottingham, United Kingdom), Natalie Chapman (University of Nottingham, United Kingdom)
Fruits such as tomato are important for a healthy balanced diet and provide an essential source for vitamins, minerals and
antioxidants. The tomato genome sequence and gene regulatory networks aid the identification of novel targets for crop
improvement allowing a better understanding of the regulatory processes involved in fruit development and ripening.
Here we describe a comprehensive gene regulatory network associated with fruit ripening that can be accessed with user friendly
computer interface and how this is helping us identify the role of major ripening regulators. A number of single gene ripening
mutants in tomato have been identified and the underlying genes are major hubs in our regulatory network. Most of these
monogenic mutants result from DNA sequence changes, but the lesion at the Cnr locus is due to hypermethylation which causes a
reduction in expression of an SBP-box transcription factor leading to non-ripening fruit. Importantly, some epi-alleles, such as Cnr,
are stably inherited from generation to generation. Naturally occurring epigenetic changes may therefore provide a novel source of
variation for breeding of complex traits. We have identified a highly complex fruit firmness associated QTL in an S.pennellii
introgression line. Further analysis of this multi locus QTL is revealing novel methylation differences that may be associated with
altered texture phenotypes.
Email Address for correspondence: graham.seymour@nottingham.ac.uk
The plasticity of grapevine berry transcriptome
Silvia Dal Santo1, Giovanni Battista Tornielli1, Sara Zenoni1, Marianna Fasoli1, Lorenzo Farina2, Andrea
Anesi1, Flavia Guzzo1, Massimo Delledonne1 and Mario Pezzotti1
1 Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15 – Ca' Vignal, 37134 5
Verona, Italy
2Dipartimento di Informatica e Sistemistica "Antonio Ruberti", Università degli Studi di Roma - "La 7
Sapienza", Via Ariosto 25, 00185 Roma, Italy
Phenotypic plasticity refers to the range of phenotypes a single genotype can express as a function of its environment. We investigated
phenotypic plasticity in grapevine by comparing the berry transcriptome in a single clone of the vegetatively-propagated common grapevine
species Vitis vinifera (cv Corvina) through three consecutive vintages cultivated in 11 different vineyards in the Verona area of Italy. Most of the
berry transcriptome clustered by vintage rather than common environmental conditions or viticulture practices, and transcripts related to
secondary metabolism showed high sensitivity towards different climates, as confirmed also by metabolomic data obtained from the same
samples. When compared 11 vineyards during one harvesting season, finding that the environmentally-sensitive berry transcriptome comprised
5% of all protein-coding genes and 18% of transcripts modulated during berry development. Specific plastic transcripts were associated mainly
with transcription factors, translation, transport, secondary metabolism and stress boxes, and plastic transcriptome reprograming was more
intense in the vintage characterized by extreme weather conditions. We also identified a set of genes that lacked plasticity, showing either
constitutive expression or similar modulation in all berries. Our data provide the first step towards the characterization of grapevine
transcriptome plasticity under different agricultural systems.