Figure 5From: Identification and expression analysis of WRKY transcription factor genes in canola (Brassica napus L.) in response to fungal pathogens and hormone treatmentsHypothetical model of WRKY network in mediating canola responses to S. sclerotiorum and phytohormones. JA/ET-responsive, but not SA-responsive genes were observed in the necrotrophic pathogen S. sclerotiorum-canola interaction [2, 5], and these induced BnWRKY genes, such as BnWRKY25, 28, 33, 53 and 75, could potentially activate the downstream JA/ET signaling pathway or cell death. Moreover, BnWRKY70 might also negatively regulate JA/ET signaling pathway while BnWRKY6 possibly modulates the expression of PR1 gene, culminating in cell death, which would benefit the infection and growth of necrotrophic fungi [114, 118]. MPK3, one of mitogen-activated protein kinases, was also observed to be induced by S. sclerotiorum in our previous microarray study [5], and MPK3 in Arabidopsis is a positive regulator of AtWRKY22/29 [39]. Solid and dashed arrows represent likely or putatively positive regulation of the downstream targets while open blocks indicate negative regulation of the downstream genes.Back to article page