Role of Arabidopsis Aspartic Protease (At1g11910) in response to B. cinerea attack

MARÍA G. GUEVARA.; D´IPPÓLITO SEBASTIÁN; FREY, MARÍA EUGENIA

Capital Federal

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Aspartic proteases (APs) are a family of proteolytic enzymes widely distributed among living organisms. Plant APs are involved in various processes as senescence, programmed cell death, reproduction and stress responses. Purpose roles to these APs are to mediate defense responses either by directly processing pathogen related proteins or to generate elicitors. In our laboratory we identified, purified and characterized two typical APs from potato (StAP1 and StAP3). These APs have are bifunctional enzymes with antimicrobial and proteolytic activities. Through the search for sequence homology, we detected the presence of three StAP1 highly homologous genes in Arabidopsis. These genes are At1g11910 (80% id) (named as APA1), At1g62290 (82% id) and At4g04460 (83% id). According with data described in Arabidopsis eFP browser APA1 is induced in leaves after Botrytis cinerea and others pathogens infection. However, there are not results that correlate the induction of this gene with the increase or decrease of the defense response of A. thaliana to B. cinerea. In the current study, we have evaluated the susceptibility degree of APA1 mutant plants to B. cinerea infection. We analysed the defense response of plants Col-0 and homozygous APA1 mutant lines infected with an inoculum of B. cinerea (1 X 10 5 spores/ml). Results obtained shown that APA1 mutant plants developed more severe disease symptoms at 3 days after infection, than wild type plants. These symptoms include extensive necrosis and chlorosis with the increased in 94% of lesion area than wild-type plants. In this work, we show that mutation of the Arabidopsis APA1 gene causes enhanced susceptibility to the necrotrophic fungal pathogen B. cinerea. Therefore, we suggest that this typical AP (APA1) would participate in the Arabidopsis defense response against to B. cinerea attack.