A WRKY Transcription Factor CbWRKY27 Negatively Regulates Salt Tolerance in Catalpa bungei

Catalpa bungei is an economically important tree with high-quality wood, which highly ornamentally valuable in China. Salinity one of the major constraints restricting growth C. bungei. However, molecular mechanism underlying salt stress response remains unknown In our previous study, a novel WRKY transcription factor gene CbWRKY27 was isolated using association mapping based on transcriptome database Yuqiu1. this found to function as transcriptional activator nucleus. The inhibited under and reactive oxygen species (ROS) but induced after abscisic acid (ABA) treatment. CbWRKY27-overexpression plants showed decreased tolerance compared wild type while enhancing sensitivity ABA-regulated lateral root length. Quantitative real-time PCR (qPCR) studies that transcript levels ABA biosynthesis (NCED3), signaling genes (ABI3 ABI5), responsive (RD29B RD22) were greatly increased stress. Under treatment, disturbed ROS homeostasis by repressing antioxidant enzymes production O2− H2O2 through down-regulation ROS-scavenging-related (APX, SOD, PER57). summary, these results indicate negatively regulates