Exploring expression patterns of PR-1, PR-2, PR-3, and PR-12 like genes in Arabidopsis thaliana upon Alternaria brassicae inoculation.

In this study, we systematically examined the expression patterns of pathogenesis-related genes in model plant Arabidopsis thaliana after Alternaria brassicae inoculation using reverse transcription polymerase chain reaction(RT-PCR). Based on the results, none of the PR-1 and PR-2 like genes were induced significantly in the unwounded local or distal leaves upon A. brassicae challenge. However, only At2g14580 of the PR-1like gene showed a significant expression in wounded leave after Alternaria challenge but not in control; confirming its expression in response to A. brassicae was aided by the wounding. Among PR-3 like genes, At2g43590 showed local early expression and other PR-3 like genes showed significant distal expression after A. brassicae infection only in unwounded but not in wounded leaf samples. Although all the three PR-12 like genes were induced in local tissues, At2g26020 was the only gene showed significant induction locally as well as systemically after pathogen infection in the both with and without wounding experiments. Therefore, among the PR-1, PR-2, PR-3 and PR-12 like genes studied, At2g26020 can be the most promising candidate for the further line of research, viz, molecular characterization of its promoter to develop pathogen-inducible promoter in response to Alternaria and to develop fungus-resistant transgenics in Brassica juncea.