Open AccessThe Zur of Xanthomonas campestris Is Involved in Hypersensitive Response and Positively Regulates the Expression of the hrp Cluster Via hrpX But Not hrpG
Author(s) -
Dongliang Huang,
Dongjie Tang,
Qing Liao,
Xiaoqian Li,
Yanan He,
JiaXun Feng,
Bo-Le Jiang,
GuangTao Lu,
JiLiang Tang
Publication year - 2009
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-22-3-0321
Subject(s) - xanthomonas campestris , biology , operon , hypersensitive response , mutant , xanthomonas campestris pv. campestris , xanthomonas , microbiology and biotechnology , genetics , gene , plant disease resistance
In bacteria, Zur is a key regulator for zinc homeostasis. Our previous work has shown that, in the phytopathogen Xanthomonas campestris pv. campestris, in addition to regulating zinc homeostasis, Zur is essential for full virulence. Here, we demonstrate that the X. campestris pv. campestris Zur is involved in hypersensitive response (HR) and positively regulates the transcription of hrpA to hrpF operons and hrpX but not hrpG. Constitutively expressing hrpX but not hrpG in the zur mutant could bypass the requirement of Zur for the expression of hrpA to hrpF operons and the induction of wild-type HR, indicating that Zur controls the expression of hrp cluster via hrpX. Promoter-gusA reporter and semiquantitative reverse-transcription polymerase chain reaction analyses revealed that HrpG controls the expression of hrpX and HrpX regulates the expression of all the six hrp operons (hrpA to hrpF) in X. campestris pv. campestris.