A key general stress response motif is regulated non‐uniformly by CAMTA transcription factors

• DOI: 10.1111/tpj.12620
• Publication Date: 2014-07-19T04:33:09Z
• Authors: Geoffrey Benn; Chang‐Quan Wang; Derrick R. Hicks; Jeffrey Stein; Cade Guthrie; Katayoon Dehesh
• Keywords: Integrated stress response; Cellular stress response

Plants cope with environmental challenges by rapidly triggering and synchronizing mechanisms governing stress-specific general stress response (GSR) networks. The GSR acts transiently in to various stresses, but the underpinning have remained elusive. To define regulatory components we exploited Rapid Stress Response Element (RSRE), a previously established functional motif, using Arabidopsis plants expressing 4xRSRE::Luciferase (RSRE::LUC) reporter. Initially, searched public microarray datasets found an enrichment of RSRE promoter sequences genes. Next, treated RSRE::LUC wounding range stress-inducible hormones detected robust LUC activity solely wounding. Application two Ca(2+) burst inducers, flagellin22 (flg22) oligogalacturonic acid, activated strongly systemically, while chelator ethylene glycol tetraacetic acid (EGTA) significantly reduced wound induction RSRE::LUC. In line signaling function transduction events leading activation RSRE, examined role CALMODULIN-BINDING TRANSCRIPTIONAL ACTIVATORs (CAMTAs) induction. Transient expression assays displayed CAMTA3 not that mutated element mRSRE. Treatment selected camta mutant lines integrated into parent plant, wounding, flg22, freezing, differential these CAMTAs potentiating RSRE. Wound studies double mutants revealed cooperative CAMTAs2 4 CAMTA 3 regulation. These provide insights reveal transcriptional modules tune key motif.