Seed comparative genomics in three coffee species identify desiccation tolerance mechanisms in intermediate seeds. (15th November 2019)

• Record Type: Journal Article
• Authors: Stavrinides, Anna K; Dussert, Stéphane; Combes, Marie-Christine; Fock-Bastide, Isabelle; Severac, Dany; Minier, Jérôme; Bastos-Siqueira, Aldecinei; Demolombe, Vincent; Hem, Sonia; Lashermes, Philippe; Joët, Thierry
• Editors: Leubner, Gerhard
• Is Part Of: Journal of experimental botany. Volume 71:Number 4(2020)
• Page Start: 1418
• Page End: 1433
• Publication Date: 2019-11-15
• Subjects: Coffea -- dehydration -- desiccation tolerance -- intermediate seeds -- late maturation -- metabolic quiescence -- respiration -- seed development -- transcriptome; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erz508
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: In contrast to desiccation-tolerant 'orthodox' seeds, so-called 'intermediate' seeds cannot survive complete drying and are short-lived. All species of the genus Coffea produce intermediate seeds, but they show a considerable variability in seed desiccation tolerance (DT), which may help to decipher the molecular basis of seed DT in plants. We performed a comparative transcriptome analysis of developing seeds in three coffee species with contrasting desiccation tolerance. 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 up-regulated during DT acquisition in the two species with high seed DT, C. arabica and C. eugenioides . By contrast, we detected up-regulation of numerous genes involved in the metabolism, transport, and perception of auxin 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 are better prepared to cease respiration and avoid oxidative stresses. Abstract : Seeds of coffee species that are more tolerant to desiccation display a specific late maturation transcriptional program that primes them to better cease respiration and avoid oxidative stress upon dehydration.