Functional genomics approaches to unravel molecular events in Quercus ilex
seed germination and seedling establishment
María Cristina Romero-Rodrígueza,b,c, Nieves Abrila, Rafael Navarro-Cerrillod, Luis
Valledore,f and, Jesús V. Jorrín-Novoa,b
a
Dpt. of Biochemistry and Molecular Biology. Agrifood Campus of International
Excellence, ceiA3. University of Cordoba. Rabanales Campus. Cordoba, Spain.
b
Agricultural and Plant Proteomics Research Group, Dpt. of Biochemistry and Molecular
Biology, ETSIAM, University of Cordoba, Spain.
c
Permanent address: Centro Multidisciplinario de Investigaciones Tecnológicas,
Universidad Nacional de Asunción, Paraguay
d
Department of Forestry Engineering, ETSIAM, University of Córdoba, Agrifood Campus
of International Excellence, ceiA3, 14071 Córdoba, Spain
e
Dpt. Biology of Organisms and Systems (BOS), University of Oviedo, Oviedo, Spain
f
Dept. of Biology & Centre for Environmental and Marine Studies, University of Aveiro,
Aveiro, Portugal
Quercus ilex (Holm oak) is the dominant tree species in natural forest ecosystems over large
areas of the Western Mediterranean Basin. Forest management and reforestation programs with this
species are facing important problems and challenges related to seed conservation and plant mortality
after transplanting. Our group is carrying out a research program in which the study of the variability
and the responses to biotic and abiotic stresses are being performed by using classical biochemical and
modern –omics approaches. In the present work proteomics, transcripts profile analysis and
metabolites determinations were combined to study at molecular level the germination and seedling
growth of Q. ilex. Gel-based combined with gel-free approach revealed important changes in
proteomic profiles that occurred in the seed after germination. Few proteins resulted altered in their
abundance during the germination period. Data suggested that the maturate seeds of Q. ilex have the
mechanisms necessary to ensuring the rapid resume of the metabolic activities requires to start the
germination process and to de novo synthesise the biomolecules required for growth. By
transcriptional, proteomics and metabolites analysis it was found that mature Q. ilex seeds show some
of the characteristics of orthodox seed, including: i) accumulation of sucrose and proteins that
contribute to the intracellular vitrification; ii) induction of the synthesis of osmoregulator raffinose
series oligosaccharides (GolS) and oxidative-related enzymes (Sod1, Gst). On the contrary, and as it
has been reported in other recalcitrant species, mature seeds present low levels of ABA, maintaining a
partially active metabolism.