Overexpression of StAP- PSI domain in Arabidopsis thaliana increases resistance to B. cinerea.

D'IPPOLITO, S.; DALEO, G.R.; PEPE, A.; GUEVARA, M.G.; FREY, M. E.; TITO, F. R.

Córdoba

Congreso; 52th Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

SAIB

Saposin-like proteins (SAPLIPs) are members of a large protein superfamily widely distributed among of living organisms. These proteins may exist for itself independently as a functional unit or as a part of a multi domain protein. Plant specific insert (PSI) is a domain present in the precursors and monomeric mature typical plant aspartic proteases (APs). This domain has structural homology with SAPLIPS with antimicrobial activity and it has cytotoxic activity towards plant pathogens. In the current study, we evaluate the resistance degree to B. cinerea in six A. thaliana transgenic lines overexpressing StAP- PSI domain. Results obtained show that the level expression of StAP- PSI has a positive correlation with the decrease in the foliar area affected by B. cinerea. Also, we determinate that StAP- PSI has a direct cytotoxic effect on B. cinerea spores and hyphae. In addition, qPCR analysis demonstrated that the expression profiles of various disease resistance genes (PR-1, PR-2, PR-5 and WRKY33) in the transgenic A. thaliana lines were increased respect to the wild type plants. These findings suggest that StAP- PSI expression enhances resistance to B. cinerea in A. thaliana, in a direct and indirect manner.