Cloning And Analysis Of A Novel P450 Gene Subfamily GbCYP82S

Verticillium wilt is a major disease affecting cotton production. But the molecular mechanism of resistance to verticillium wilt of cotton is still unclear currently. Cytochrome P450 enzymes are a class of widely present in microorganisms, plants and animals, organisms such as the oxidation enzyme system, the broad participation of anabolic substances in plants biological synthesis and detoxification path,and has important effect on plant growth development and disease.Sea Island cotton varieties have resistantce to verticillium wilt, so we constructed the suppression subtractive cDNA library which was induced by verticillium wilt for ’hai 7124’.We selected a P450 gene EST sequence from the cDNA library and and named it as GbCYP82SX.We obtained full-length gene cDNA sequence by RACE, then got three highly homologous sequences and found that the these genes should belong to a new classification of cotton P450 subfamily, named GbCYP82S. Construct the RNAi vector, overexpressing vector and the promoter expressing vector of GbCYP82S subfamily, and transformed cotton lines YZ1’to verify the effect of genes in resistance of cotton. When GbCYP82S subfamily was inhibited, the majority of the stems of transgenic cotton seedlings have similar lesion necrosis which led to death of most transgenic seedlings in the absence of any pathogen infecting the organization. Real-time RT-PCR analysis showed that the GbCYP82S subfamily genes expression in transgenic plants was significantly decreased in the plant which has lesion mimic. The expression of homologous genes of Arabidopsis thaliana SAR marker gene PR1 and JA receptor protein gene COI1 significantly reduced in cotton. The Arabidopsis COI1 gene mutations are not sensitive to jasmonic acid and lose the disease resistance, but the RNAi transgenic cotton plants of GbCYP82S subfamily increased sensitivity to jasmonic acid, which demonstrates that the GbCYP82S subfamily may be related for jasmonic acid metabolism or signal transduction of the cotton. Preliminary results of existing research indicate that GbCYP82S subfamily may be play a role in plant disease resistance.