Identification of the Transcription Factors RAP2-13 Activating the Expression of CsBAK1 in Citrus Defence Response to Xanthomonas citri subsp. citri

Citrus canker is a quarantined disease caused by the bacterial plant pathogen Xanthomonas citri subsp. (Xcc), which causes persistent surface damage, leaf and fruit drop, tree decline in citrus plants. The cultivar Citron C-05 (Citrus medica L.) disease-resistant genotype identified after years of screening at National Center for Improvement (Changsha), displays allergic, necrotic, responses to Xcc. In this study, BAK1 gene was be resistance involved plant-microbe interaction between Functional investigations revealed that both CsBAK1 (C. sinensis BAK1) or CmBAK1(C. could inhibit growth Xcc some extent when transiently expressed susceptible ‘Bingtang’ sweet orange. Critical regions CmBAK1 promoter sequence were creating downstream deletions exposing mutants determine effects on phenotype; 426 bp region (−2000~–1574) as key functional responsible eliciting hypersensitive response Through arrayed cDNA libraries yeast one-hybrid assays, basic APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor CmRAP2-13 binds directly activates expression identified. Moreover, transcriptional analysis an obvious increase transcript levels CsRAP2-13 C-05, American citron, Finger citron. we present identification activators are found interact with proteins These results reveal coordinated regulatory mechanism RAP2-13, may defence through regulation BAK1.