The virulence factor AvrXa7 of Xanthomonas oryzae pv. oryzae is a type III secretion pathway-dependent nuclear-localized double-stranded DNA-binding protein.

ABSTRACT: AvrXa7 is a member of the avrBs3 avirulence gene family, which encodes proteins targeted to plant cells by a type III secretion apparatus. AvrXa7, the product of avrXa7, is also a virulence factor in strain PXO86 of Xanthomonas oryzae pv. oryzae. Avirulence and virulence specificities are associated with the central repeat domain, which, in avrXa7, consists of 25.5 direct repeat units. Mutations in three C-terminal nuclear localization signal motifs eliminated avirulence and virulence activities in rice and severely reduced nuclear localization in a yeast assay system. Both pathogenicity functions and nuclear localization were restored on the addition of the sequence for the nuclear localization signal motif from SV40 T-antigen. The loss of avirulence activity because of mutations in the a

SUBMITTER: Yang B 

PROVIDER: S-EPMC16946 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature