Seed comparative genomics in three coffee species evidence desiccation tolerance mechanisms among intermediate seeds

ABSTRACT: In contrast to the desiccation tolerant (DT) ‘orthodox’ seeds, the so-called ‘intermediate’ seeds cannot survive complete drying and are short-lived. All species of the genus Coffea produce intermediate seeds but show a considerable variability for the seed DT level, which may help to decipher the molecular basis of seed DT in plants. We thus led a comparative transcriptome analysis of developing seeds in three coffee species with contrasting seed DT levels. Seeds of all species shared a major transcriptional switch during late maturation that governs a general slow-down of metabolism. However, numerous key stress-related genes, including those coding for the late embryogenesis abundant protein EM6 and the osmosensitive calcium channel ERD4, were upregulated during DT acquisition in the two species with high seed DT, C. arabica and C. eugenioides. By contrast, an upregulation of numerous players of the metabolism, transport and perception of auxin was observed in C. canephora seeds with low DT. Moreover, species with high DT showed a stronger down-regulation of the mitochondrial machinery dedicated to the tricarboxylic acid cycle and oxidative phosphorylation. Accordingly, respiration measurements during seed dehydration demonstrated that intermediate seeds with the highest DT levels are better prepared to cease respiration and avoid oxidative stresses.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Coffea Eugenioides Coffea Canephora Coffea Arabica (arabian Coffee)

TISSUE(S): Plant Cell, Endosperm

SUBMITTER: sonia hem  

LAB HEAD: Thierry Joët

PROVIDER: PXD015806 | Pride | 2020-05-26

REPOSITORIES: Pride