Gene expression profiling of defense-related genes resistant to Septoria tritici blotch in wheat

Abstract

To recognize defense-related genes in wheat plants resistant to Septoria tritici leaf blotch (STB) caused by Mycosphaerella graminicola, we utilized complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) analysis. An analysis of transcript-derived fragments’ (TDFs) patterns of the studied resistant wheat cultivar, Frontana, was compared with that of the susceptible cultivar, Seri 82, and related controls. Sampling was done at nine timepoints from 0 h to 24 days post inoculation. Transcripts from Frontana cultivar that had enhanced expression post inoculation (170) were isolated, recovered, cloned, sequenced and analyzed via BLAST. A total of 47 TDFs had significant protein homology. The expression profile of nine genes was obtained by real-time PCR. These genes contained PCI domain, protein tyrosine kinase, zinc-finger-homeodomain (ZF- HD) protein dimerization region, leucine-rich repeat receptor-like protein kinase, WD40 domain, diacylglycerol kinase catalytic domain and geranylgeranyl transferase type II, ATPases associated with a wide variety of cellular activities and FKBP-type peptidyl prolyl cis-trans isomerase. The function of these genes relative to defense response against the pathogen was described. Key words: Triticum aestivum, Mycosphaerella graminicola, cDNA-AFLP, resistant wheat, transcript-derived fragments, Septoria tritici.