Open AccessThe tomato UV‐damaged DNA‐binding protein‐1 (DDB1) is implicated in pathogenesis‐related ( PR ) gene expression and resistance to Agrobacterium tumefaciens
Author(s) -
LIU JIKAI,
LI HANJING,
MIAO MIN,
TANG XIAOFENG,
GIOVANI JIM,
XIAO FANGMING,
LIU YONGSHENG
Publication year - 2012
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/j.1364-3703.2011.00735.x
Subject(s) - biology , agrobacterium tumefaciens , agrobacterium , ddb1 , mutant , gene , arabidopsis , genetics , pathogenesis related protein , gene expression , microbiology and biotechnology , ubiquitin ligase , transformation (genetics) , ubiquitin
SUMMARY Plants defend themselves against potential pathogens via the recognition of pathogen‐associated molecular patterns (PAMPs). However, the molecular mechanisms underlying this PAMP‐triggered immunity (PTI) are largely unknown. In this study, we show that tomato HP1/DDB1 , coding for a key component of the CUL4‐based ubiquitin E3 ligase complex, is required for resistance to Agrobacterium tumefaciens . We found that the DDB1‐deficient mutant ( high pigment‐1 , hp1 ) is susceptible to nontumorigenic A. tumefaciens . The efficiency of callus generation from the hp1 cotyledons was extremely low as a result of the necrosis caused by Agrobacterium infection. On infiltration of nontumorigenic A. tumefaciens into leaves, the hp1 mutant moderately supported Agrobacterium growth and developed disease symptoms, but the expression of the pathogenesis‐related gene SlPR1a1 and several PTI marker genes was compromised at different levels. Moreover, exogenous application of salicylic acid (SA) triggered SlPR1a1 gene expression and enhanced resistance to A. tumefaciens in wild‐type tomato plants, whereas these SA‐regulated defence responses were abolished in hp1 mutant plants. Thus, HP1/DDB1 may function through interaction with the SA‐regulated PTI pathway in resistance against Agrobacterium infection.