Regulation of plant immunity through ubiquitin‐mediated modulation of Ca2+–calmodulin–AtSR1/CAMTA3 signaling

• DOI: 10.1111/tpj.12473
• Publication Date: 2014-02-17T11:18:29Z
• Authors: Lei Zhang; Liqun Du; Chenjia Shen; Yanjun Yang; B.W. Poovaiah
• Keywords: 0301 basic medicine; Proteasome Endopeptidase Complex; Arabidopsis Proteins; Ubiquitin; Arabidopsis; Ubiquitination; Pseudomonas syringae; Cullin Proteins; 03 medical and health sciences; Host-Pathogen Interactions; Proteolysis; Plant Immunity; Calcium Signaling; Carrier Proteins; Transcription Factors

Transient changes in intracellular Ca(2+) concentration are essential signals for activation of plant immunity. It has also been reported that suppress salicylic acid-mediated defense through AtSR1/CAMTA3, a member the /calmodulin-regulated transcription factor family is conserved multicellular eukaryotes. How plants overcome this negative regulation to mount an effective response during stage surge unclear. Here we report identification and functional characterization important component ubiquitin ligase, associated AtSR1 turnover. The interaction protein 1 (SR1IP1) was identified by CytoTrap two-hybrid screening. loss-of-function mutant SR1IP1 more susceptible bacterial pathogens, over-expression confers enhanced resistance, indicating acts as positive regulator defense. act same signaling pathway regulate contains structural features substrate adaptor cullin 3-based E3 shown serve recruits ubiquitination degradation when challenged with pathogens. Hence, positively regulates immunity removing suppressor AtSR1. These findings provide mechanistic insight into how -mediated actions coordinated achieve