Cloning and characterization of pl1 encoding an in planta-secreted pectatelyase of Fusarium oxysporum

A pectate lyase (PL1) From the tomato vascular wilt pathogen Fusarium oxysp orum f.sp. lycopersici was previously characterized, and evidence was obtai ned for its production in planta, The gene encoding PL1 was isolated From a genomic library of F: oxysporum f.sp. lycopersici, Pl1 encodes a 240 amino -acid polypeptide with one putative N-glycosylation site and a 15 amino-aci d N-terminal signal peptide. PL1 showed 89%, 67%, 55% and 56% identity with the products of the Fusarium solani f.sp, pisi pelA, pelB, pelC and pelD g enes, respectively. A single copy of the gene was detected in different for mae speciales of F. oxysporum. The pll transcript was observed during growt h on polygalacturonic acid sodium salt and tomato vascular tissue, but not on pectin or glucose, RT-PCR showed pll expression in roots and stems of to mato plants infected by F. oxysporum f.sp, lycopersici.