An ERF transcription factor from Brassica oleracea: a new member of the emerging pathogenicity hub in plant-Xanthomonas interactions

TAL effectors (TALEs), which induce the expression of specific plant genes to promote infection, are the main pathogenic determinants of different Xanthomonas bacteria. However, investigation of TALEs from Xanthomonas campestris pv. campestris, which causes black rot disease of crucifers, is in its infancy.

In this study, we used PCR-based amplification in conjunction with SMRT amplicon sequencing to identify TALE genes in several Xanthomonas campestris pv. campestris strains and performed computational prediction in conjunction with RT-PCR-based analysis to identify their target genes in Brassica oleracea.

Transcription factor from the AP2/ERF family was predicted to be putative target gene for the conserved TALEs present in multiple Xanthomonas campestris pv. campestris strains. Its expression dramatically increased upon leaf inoculation with strains harbouring such TALEs.

Several members of the AP2/ERF factor family from different plant species were identified as targets of TALEs from various Xanthomonas species, which suggests that they constitute a new pathogenicity hub in plant-Xanthomonas interactions.