Abstract:

【Objective】 The objective of the research is to analyze the gene expression profile of wheat near-isogenic line TcLr38 induced by Puccinia triticina and to detect the fragments related to disease-resistant gene expression. 【Method】 The study was carried out to detect the differential expression of genes in TcLr38 and Thatcher inoculated with avirlent P. triticina strain 05-22-65 (THTS) by complementary DNA amplified fragments length polymorphism (cDNA-AFLP) analysis. 【Result】 Seventy-six pairs of primers were used to amplify products for cDNA-AFLP analysis. About 3800 bands were detected and the average number of bands per pair of primers amplified was 50. Twenty-eight of 76 primer combinations for cDNA-AFLP analysis amplified specific bands. Polymorphic bands between TcLr38 and Thatcher were grouped into eight different types, and three types of them were supposed to correspond to the disease-resistant reactions. Ninety-five transcripts derived fragments (TDFs) were selected for their differential expression from wheat near-isogenic line TcLr38 and Thatcher. And nineteen TDFs were upregulated and only expressed in the inoculated TcLr38, whereas 8 TDFs were suppressed. Twenty-one TDFs were sequenced and analyzed. BLASTx analysis showed that 17 TDFs had the homologous sequences with the sequence in GenBank, and fifteen were homologous with the known function genes. 【Conclusion】 The TDFs confer protein kinase C, ATP binding protein, receptor-like kinase, signal transduction histidine kinase, putative dnaK suppressor protein DksA, Methionine-tRNA synthetase, Peptidase M23, Ran GTPase activating protein 1, and Enoyl-Coenzyme A hydratase were supposed to correspond to the expression of the disease-resistant reactions.

Key words: wheat leaf rust, Lr38, cDNA-AFLP, differential expression