SC35 and EIF4A1 characterization in Arabidopsis

LUCIANA CASTRO; ARICO DENISE; MAZZELLA AGUSTINA

Congreso; RAFV; 2021

Light is an environmental factor that regulates plant development. Light triggers different signaling cascade that activates genes during plant development, some of which are regulated by a process of phosphorylation-dephosphorylation. In a large scale- phosphoproteomic analysis we identified several proteins that changed their phosphorylation status independently of photoreceptors activation. One of these phosphoproteins is SC35, which is an alternative splicing factor, and the other one is EIF4A1 which is an eukaryotic initiation factor involved in the initiation phase of translation. As a first step we characterize these proteins with mutants and transgenic plants of each gene, assessing their phenotype during plant development. Preliminary results show, that overexpression of SC35 can cause a pleiotropic change in Arabidopsis development when grown under continuous light condition, while under short day photoperiod, the pleiotropic effect is attenuated. Also, under 30°C and dark conditions, these transgenic plants present reduced hypocotyl elongation compared to the wild-type plants. On the other hand, eif4a1 mutants, displayed a significant shorter hypocotyl compared to the wild-type plants, in part as result of retarded germination in the mutants. Our next step is to study the impact of the phosphorylation changes in these phenotypes to evaluate the biological function of phosphorylation.