Snakin-1: involvement in redox homeostasis and hormonal crosstalk

NAHIRÑAK V; GONZALEZ DE URRETA, MARTIN; BARRIOS BARON P; ALMASIA N I; RIVAROLA, MAXIMO; PANIEGO, NORMA; HOPP H E; VAZQUEZ ROVERE C

Foz de Iguazú

Congreso; International Plant Molecular Biology Congress; 2015

Snakin/GASA proteins are widely distributed among plant species. Even though many of these genes were characterized and different biological functions were suggested, little is known about their mode of action. Interestingly, all of them maintain 12 cysteines of the C-terminus in highly conserved positions that are probably responsible for their protein structure and were shown to be essential for their biochemical activity as antioxidants. On the other hand, most of Snakin/GASA genes are regulated by hormones and participate in the interaction between different hormonal signaling pathways; and therefore, they are involved in plant development and plant environmental responses.Snakin-1 is a member of the Snakin/GASA family isolated from Solanum tuberosum that was found to be active against pathogens in vitro and we demonstrated that its overexpression in potato enhances resistance to Rhizoctonia solani and Erwinia carotovora. We recently showed that Snakin-1 silencing resulted in an abnormal phenotype affecting cell division, leaf primary metabolism and cell wall composition demonstrating that it has additional roles in growth and development.In the present work, we study the involvement of Snakin-1 in redox homeostasis and hormonal crosstalk. We analyzed reactive oxygen species (ROS) accumulation in transgenic (Snakin-1 overexpressing and silencing lines) and wild type plants through different histochemical stainings. Moreover, the endogenous levels of hormones related to stress responses as well as to plant growth and development were determined in leaves and stems of wild-type and transgenic plants. Finally, in order to gain more insights into the molecular mechanism underlying the role of Snakin-1, analyses of transgenic and WT transcriptomes were further performed from shoot apex and leaves samples.