The Functional Analysis Of Candidate S-gene TaHIPP1

Pst.Stripe rust is an airborne,low temperature fungal disease that seriously threatens the growth of wheat.Pst.Stripe rust has the characteristics of strict parasitism,high variability,widespread prevalence,airflow propagation,and high spore reproduction rate,causing stripe rust epidemic outbreaks and wheat grain deficiencies.There are many ways to control Pst.Stripe rust.It is the most effective and environmentally friendly method to use wheat disease resistant varieties.However,due to the frequent variation of toxicity of stripe rust and appearing of new toxic races,making wheat varieties vulnerable to rust failur e and losing their use value,the research of susceptible genes provides new ideas for breeding new disease-resistant varieties.In this study,we have obtained the following results:1、An EST sequence of wheat heavy metal-associated prenylated protein（TaHIPP）was obtained from an affinity system of wheat-strip rust interactions.Using wheat"Suwon 11"as a template,the gene was cloned by RT-PCR.The gene was 736 bp in length and contained a468 bp open reading frame,encoding a peptide chain consisting of 155 amino acids.By protein sequence analysis,it contains a heavy metal-associated domain,nuclear localisation signals and an isoprenylation motif（Caa X motif）.Through scanning the wheat protoplast cells with microscopy,TaHIPP1 was subcellularly localized in the nucleus and cytoplasm.TaHIPP1 over-expression in yeast（Schizosaccharomyces pombe）significantly increased the cell growth rate under Cu²⁺and high salinity stresses.2、The qRT-PCR technique was used to analyze the expression characteristics of TaHIPP1 under both bio and abiotic stress.It was found that the expression of this gene was up-regulated in compatible reaction,but not in the incompatible reaction.In abiotic stress,the expression of this gene is upregulated by ABA exposure and wounding.3、In addition,TaHIPP1 was shown to enhance the susceptibility of wheat to Pst as determined by virus-induced gene silencing.4、A interaction protein,TaVDAC1,was identified by uisng a yeast two-hybrid（Y2H）screen.These data indicate that TaHIPP1 may be a susceptible gene and play an important role in plant defense responses.