Abstract:

【Objective】 A novel Hin1 gene induced by the stripe rust pathogen was cloned from wheat to better understand its role in wheat defense to Puccinia striiformis f.sp. tritici and to abiotic stresses. 【Method】 In-silico cloning and RT-PCR were combined to isolate a gene which might encode HIN1 from wheat Suwon 11 infected by stripe rust pathogen. Bioinformatics tools were applied to analyze both the DNA sequence and protein sequence. The expression patterns of the gene in wheat organs, as well as interactions with stripe rust pathogen, induction of exogenous phytohormones and abiotic stresses, were investigated using real time quantitative RT-PCR. 【Result】 The wheat Hin1 gene designated as TaHin1 was obtained. Open reading frame (ORF) of TaHin1 was 642 bp in length, encoding 213 amino acid residues with a molecular weight of 23.24 kD and predicted pI value of 8.67. TaHIN1 might be a secreted protein, containing a signal peptide and a HIN1 domain. TaHIN1 shared about 80% similarity with HIN1 from broomcorn and rice. TaHin1 expresses in wheat leaf, stem and root with no significant difference. Challenged by stripe rust fungus, TaHin1 was induced by Puccinia striiformis f.sp. tritici only in incompatible interaction. TaHin1 was up-regualted by exogenous salicylic acid and jasmonic acid while down-regulated by abascisci acid. Exogenous ethylene could not induce the expression. TaHin1 was obviously up-regulated by various abiotic stresses such as high salinity, drought, mechanical wound and low temperature. 【Conclusion】 TaHin1 gene was firstly cloned and characterized from wheat infected by stripe rust fungus. TaHin1 might facilitate wheat defence through salicylic acid and jasmonic acid pathways, while abscisci acid might play a negative role in the defence. TaHin1 also played a role in response to abiotic stresses.

Key words: stripe rust, TaHin1, in-silico cloning, transcriptional profiling