Snakin-1 peptide is involved in defense and development

NAHIRÑAK, V; ALMASIA, NI; HOPP, HE; VAZQUEZ- ROVERE, C

Potrero de Funes, San Luis

Congreso; XLVII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

SAIB

Snakin-1 (StSN1) is an antimicrobial peptide isolated from Solanum tuberosum that was shown to be active against fungal and bacterial pathogens in vitro and in vivo. Others members of its family (snakin/GASA) have already been implied in diverse processes such as cell division/elongation, transition to flowering and signaling pathways and it has been demonstrated that some of them are transcriptionally regulated by gibberellic acid (GA) or paclobutrazol (PAC; an inhibitor of GA biosynthesis). We have previously obtained potato transgenic lines overexpressing or silencing StSN1 and even though overexpressing lines did not show remarkable phenotypic differences from wild type, silenced plants exhibited altered leaf morphology, internode elongation, flowering timing and tuberization. In this work we demonstrated that internode elongation of plants grown either in vitro or pot-cultured was rescued by exogenous GA3. We also suggested that in potato StSN1 promoter was induced after GA treatments by analyzing transgenic lines harboring StSN1 promoter region fused to GUS reporter gene. Finally, we presented qRT-PCR analyses of StSN1 and genes involved in GA metabolism expression levels in treated or transgenic plants. Altogether, our results suggest that StSN1 is involved in GA metabolism and consequently it has a dual function in defense and development.