IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Role of miRNAs expression against Potato virus X (PVX) and the PVX-25K efector protein in Solanum tuberosum.
Autor/es:
TASSELLI S.E.; SIMONSINI S.A.; GERHARDT N.C.; MARTIN A.P. ; MARANO M.R.
Lugar:
Foz Iguazú
Reunión:
Congreso; 11th Congress of International Plant Molecular Biology.; 2015
Institución organizadora:
IPMB 2015 South America
Resumen:
Solanum tuberosum (potato) cv. Pentland Ivory carrying the resistance gene Nb, confers hypersensitive response (HR) to PVX strain ROTH1. The PVX 25-kDa protein (p25) is the effector of Nb-mediated HR. In Nicotiana benthamiana and Arabidopsis thaliana plants, p25 acts as a viral suppressor of RNA silencing (VSRs) via degradation of AGO1 protein through the proteasome pathway. In addition, it has been shown that the accumulation of the miR168 is an early function of VSRs and this activity is associated with the control of the endogenous AGO1 protein level. In this study, we analyzed the expression levels of miR168 against PVX-ROTH1 in resistant (genotype Nb), and susceptible (genotype nb) potato plants in order to identify the role of this miRNA in both, the basal defense layer through RNA silencing and ETI (effector-triggered immunity). Preliminary results have shown significant differences in the accumulation of miR168 between both pathosystems, showing an up-regulation only in the incompatible one and no differences in the compatible system at early times of infection (24 y 48 hpi). However, the levels of the mRNA of ago1 do not have shown relevant differences. Therefore, it is interestedly to evaluate the levels of the AGO1 protein in the systems under study. Others miRNAs, miR398 and miR408, involved in defense pathways, such as ROS accumulation and strengthening of cell wall, respectively, show different expression levels between both interactions. In addition, it has been done Agrobacterium-mediated expression assays of p25. It have been demonstrated that the p25 protein is capable by its one to generate an HR at the incompatible system and the behavior of the miRNAs and they corresponding targets genes under study have been similar to the infection assays. Further studies are required to understand the role of miR168 in the Nb-mediated defense responses to PVX or its viral efector p25.