Séminaire IBIP

Les séminaires ont lieu sur le Campus Montpellier SupAgro/INRA de La Gaillarde (2, place P. Viala Montpellier)

Jeudi 30 mai à 14h00 – Amphi 2 (Bât 2 Bis)

Tom Laloum

Post-doctorant, Equipe Memo IPSiM

Repression of ABA-mediated stress responses during early seedling development by two Arabidopsis SR proteins

In plants, osmotic stress promotes the synthesis of the hormone abscisic acid (ABA), which triggers major gene expression changes and physiological responses to adapt to adverse environments. While the transcriptional and posttranslational control of ABA-mediated stress responses is well established, emerging evidence points also to a central role for posttranscriptional regulation in this process. In agreement, plant mutants defective in different RNA-binding proteins have been found to be severely impaired in ABA-mediated stress responses. We recently identified the Arabidopsis thaliana SCL30a and SR34a genes — encoding serine/arginine-rich (SR) proteins belonging to a conserved family of RNA-binding proteins — as negative regulators of ABA-mediated stress responses during early plant development. In fact, loss-of-function mutants for these SR proteins are hypersensitive to exogenous ABA as well as to high salinity and drought during seed germination and seedling transition from heterotrophic to autotrophic growth. To gain mechanistic insight into the mode of action of plant SR proteins, the RNAs targeted by one of these RNA-binding proteins were identified using a combination of iCLIP and RNA-seq analyses. Our results shed new light on how plant SR proteins regulate alternative splicing to control physiological responses under environmental stress.

Contact : tou-cheu.xiong@inrae.fr