Arabidopsis cysteine-rich receptor-like kinase 45 positively regulates disease resistance to Pseudomonas syringae

Abstract

Arabidopsis cysteine-rich receptor-like protein kinase 45 (CRK45) was found to be involved in ABA signaling in Arabidopsis thaliana previously. Here, we reported that it also positively regulates disease resistance. The CRK45 overexpression plants increased expression of the defense genes, and enhanced resistance to Pseudomonas syringae whereas the crk45 mutant were more sensitive to P. syringae and weakened expression of the defense genes, compared to the wild type. We also found that treatment with P. syringae leads to a declined expression of CRK45 in the npr1 mutant and the NahG transgenic plants. At the same time, significantly decreased expression of CRK45 transcript in the wrky70 mutant than that in the wild type was also detected. Our results suggested that CRK45 acted as a positive regulator in Arabidopsis disease resistance, and was regulated downstream of NPR1 and WRKY70 at the transcriptional level.

Keywords: AIG1; Arabidopsis thaliana; AvrRpt2-induced gene 1; CRK45; CRKs; DIG; JA; LAR; MeJA; NPR1; PR1; PR2; Pseudomonas syringae; Pseudomonas syringae pv. tomato DC3000; Pst DC3000; RLKs; Receptor-like protein kinase; SA; SAR; Salicylic acid; TF; TGA; TGACG sequence-specific binding protein; WRKY DNA binding proteins; WRKY70; WRKYs; cysteine-rich receptor-like kinases; digoxigenin; jasmonic acid; local acquired resistance; methyl jasmonic acid; non-expressor of PR genes 1; pathogenesis-related gene 1; pathogenesis-related gene 2; receptor-like kinases; salicylic acid; systemic acquired resistance; transcription factor.