EASTBIO BBSRC PhD Studentship Project – University of Dundee
Project title: Discovery of Architectural Traits in Barley under the Control of
Phase Transition Transcription Factors
Start Date: 1 September 2015
Supervisor 1 (Lead): Dr. Sarah McKim
http://www.lifesci.dundee.ac.uk/people/sarah-mckim
Supervisor 2: Dr. Piers Hemsley
A cereal plant’s architecture has a huge impact on how much grain it will
produce and how easily it can be harvested. From the earliest farmers
onwards, humankind has selected for modified cereal architectures
associated with better yield. Any plant’s final architecture, including that of
cereals, reflects the progression of growth phases, broadly moving from
vegetative to reproductive. In temperate cereals, such as barley and wheat,
vegetative growth involves production of a main shoot giving rise to leaves
and additional shoots; following the transition to the reproductive phase, shoot
tips form flowering ‘spikes’ which initiate rows of reproductive units called
spikelets which each develop into grain. Although produced at the end of the
life cycle, grain yield often reflects these earlier developmental events. For
instance, yield may be affected by the seedling’s leaf photosynthetic area, the
number of shoots forming fertile spikes or the number spikelets formed per
spike. To meet an ever-increasing need for cereal foodstuffs, we must
develop even higher-yielding varieties more quickly than ever before. To help
this effort, our lab works towards the elucidation of the underlying molecular
mechanisms guiding cereal growth and development. By learning which
genes control which architectural traits, we hope to unlock them as targets for
predictive molecular breeding strategies. Thus, candidates inspired by a
desire to improve food security are ideally suited to this position.
We focus on miRNA-regulated transcription factor families important for
growth phase transitions in plants since recent evidence suggests that they
control suites of vegetative and reproductive traits relevant to yield. However,
little is known about individual gene function specificity or their downstream
mechanisms. Using state-of-the-art molecular techniques, this studentship will
study barley as a developmental model to discover the architectural traits
controlled by these factors. This project will start with the generation and full
characterisation of transgenic lines misexpressing selected and tagged
transcription factors. Transgenic phenotypes will form the basis of expression
studies, miRNA-targeting experiments and genetic analyses with existing
architectural mutant lines. The most promising transgenic lines will be used to
uncover
targets
of
these
transcription
factors
by
chromatin
immunoprecipitation (ChIP), thereby revealing other candidate breeding loci.
The student conducting this project will master many transferable molecular
techniques including construct cloning, mRNA/miRNA/protein quantification,
western blotting, in situ hybridisation, and ChIP in addition to plant culture and
glasshouse skills. The student will train within the unique graduate
environment offered by the Division of Plant Sciences, based at the James
Hutton Institute (JHI), a centre of world-class expertise in barley. The student
will participate in both streams of post-graduate training offered at the JHI and
CLS/UoD. There will also be multiple opportunities to engage with the public
about your research. In addition to multiple opportunities within the training
programmes for student presentation, the McKim lab emphasises the
importance of attending and presenting at conferences as a key part of
graduate student training. The ideal student will work well independently but
enjoy contributing to group work within the research team. We are particularly
keen on PhD candidates who thrive on technical challenge and have a
passion for discovery.
References:
Wang and Wang, The miR156/SPL Module, a Regulatory Hub and Versatile
Toolbox, Gears up Crops for Enhanced Agronomic Traits, Molecular Plant
(2015), http://dx.doi.org/10.1016/j.molp.2015.01.008
Miura et al (2010) OsSPL14 promotes panicle branching and higher grain
productivity in rice. Nature Genetics. 42: 545–549.
http://www.nature.com/ng/journal/v42/n6/abs/ng.592.html
Houston and McKim et al (2013) Variation in the interaction between alleles of
HvAPETALA2 and microRNA172 determines the density of grains on the
barley inflorescence. P.N.A.S. USA. 110: 16675–16680.
http://www.pnas.org/content/110/41/16675