CONTRIBUTION OF RPL10 PROTEINS IN ARABIDOPSIS ABA SIGNALING

CLAUDIA P. SPAMPINATO; CASATI PAULA; R.S. RAMOS; MA LORENA FALCONE FERREYRA

Paraná

Congreso; LIV Reunión SAIB 2018; 2018

Ribosomal protein L10 (RPL10) is an integral component of eukaryotic ribosomes large subunit. The protein is best known for its role in proteintranslation, but also has extra-ribosomal functions in different organisms. Arabidopsis thaliana contains three genes coding for RPL10 (RPL10AB-C). Previously, we demonstrated that these three genes are not functionally equivalent and are differentially involved in plant development andabiotic stress. Considering that abscisic acid (ABA) regulates plant growth, development and stress responses, we here investigated theparticipation of RPL10 proteins in ABA signaling pathways. We first analyzed seed germination and early development in simple rpl10sArabidopsis mutant plants grown in the presence or absence of exogenous ABA. The results indicate that rpl10A mutant plants showed lesssensitivity, whereas rpl10B and rpl10C mutants showed hypersensitivity to the hormone with respect to WT plants. Then, we evaluated theinhibition of primary root elongation by ABA by transferring 7-day-old seedlings germinated in the absence of ABA to medium supplementedwith the hormone.While rpl10A mutant plants exhibited less inhibition, rpl10B and rpl10C mutants showed a more pronounced inhibition of rootgrowth by ABA treatment than Wild Type Col-0 plants. A similar ABA sensitivity phenotype was observed in rpl10 mutants with regard topetiole length and leaf yellowing. Surprisingly, the expression of the three RPL10 genes was induced both during seed germination and afterpost-germinative growth by exogenous ABA treatment. Taken together, these data provide evidence that RPL10 proteins may play different rolesduring ABA signaling.