ROLE OF NITRIC OXIDE IN UV-B INDUCED PHOTOMORPHOGENESIS THROUGH UVR8 SIGNALING PATHWAY

LATORRE, LUCAS; FERNÁNDEZ, MARÍA BELÉN; CASSIA, RAÚL

Congreso; RAFV 2021; 2021

UV-B radiation it?s a component of sunlight, that comprehend wavelengths from 280nm to 320nm. The ozone layer filters the UV-B radiation but a small part reaches the Earth surface. This radiation serves as stressor and as a signal for plants.Nitric oxide acts a signaling molecule and participates in both physiological and stress acclimation responses in plants. Our objective is to bring light in the role of nitric oxide in the UV-B induced photomorphogenesis. To abord this issue, seedlings of Arabidopsis thaliana were growth in continuous UV-B radiation and endogenous nitric oxide was measure in hypocotyl after 5 days of growth. Results shown that uvr8 mutants, that lacks of UVR8 photoreceptor and don´t inhibit elongation of hypocotyl in response to UV-B, has lower levels of NO compared to wild type. Moreover, nitric oxide exogenous applied recover the response to UV-B in uvr8 mutants. Previous reports obtained in our lab, indicate that the gen corresponding to nitrate reductase 1 (NIA1) involved NO synthesis, is upregulated by UV-B by the UVR8-dependent pathway. In addition to this, in-silico analysis of the components of the UVR8 signaling pathway has revealed the existence of potentially S-nitrosylable conserved cysteines in COP1, NIA1, PHR1, IAA12 and MYB12. Altogether, this evidence aims to a fundamental role of nitric oxide in regulation of UV-B induced photomorphogenesis.