Authors: Michela Osnato, Unai Cereijo, Jan Sala, Luis Matías-Hernández, Andrea E. Aguilar-Jaramillo, María Rosa Rodríguez-Goberna, José Luis Riechmann, Manuel Rodríguez-Concepción, Soraya Pelaz
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Barcelona 08193, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain
Publication: The Plant Journal
Date: October, 2020
Members of the plant specific RAV family of transcription factors regulate several developmental and physi-ological processes. In the model plantArabidopsis thaliana, the RAV TEMPRANILLO 1 (TEM1) and TEM2control important phase changes such as the juvenile to adult and the vegetative to reproductive transi-tions. Besides their known regulatory function in plant development, a transcriptomics analysis of trans-genic plants overexpressingTEM1also revealed overrepresentation of Gene Ontology (GO) categoriesrelated to abiotic stress responses. Therefore, to investigate the biological relevance of these TEM-depen-dent transcriptomic changes and elucidate whether TEMs contribute to the modulation of plant growth inresponse to salinity, we analyzed the behavior ofTEMgain and loss of function mutants subjected to mildand high salt stresses at different development stages. With respect to increasing salinity,TEMoverexpress-ing plants were hypersensitive whereas thetem1 tem2double mutants were more tolerant. Precisely,tem1tem2mutants germinated and flowered faster than the wild-type plants under salt stress conditions. Also,tem1 tem2plants showed a delay in salt-induced leaf senescence, possibly as a consequence of downregu-lation of jasmonic acid biosynthesis genes. Besides a shorter life cycle and delayed senescence,tem1 tem2mutants appeared to be better suited to withstand oxidative stress as they accumulated higher levels ofa-tocopherol (an important antioxidant metabolite) and displayed a slower degradation of photosyntheticpigments. Taken together, our studies suggest novel and crucial roles for TEM in adaptive growth as theymodulate plant development in response to environmental changes such as increasing soil salinity.