The Expression Regulation Of UGT2B10 And TGM5 Genes And Their Role In Related Diseases

Part I:UDP glucuronosyl transferase(UGT)family enzymes are one of the most important enzymes in catalyzing the glucuronic acid binding reaction,which is the most important phase Ⅱ metabolic pathways.UGTs catalyze a variety of endogenous substances and exogenous compounds binding uridine diphosphate-glucuronic acid(UDP-GA),thus producing more soluble water-soluble metabolites for easy excretion from the body,which plays a pivotal role in detoxification.The substrates of UGTs include steroid hormones,bilirubin,thyroid hormone,a variety of drugs and so on.The studies reported that gene polymorphism of UGTs may influence the development and prognosis of caners,especially breast and prostate cancer,due to their role in the biotransformation of endogenous and externalsubstrates.Members of the UGT family have its own molecular regulation mechanism.UGT2B10 is a crucial member of UGT family and multiple common SNPs have been observed in its promoter region.However,their role in expression regulation has never been investigated.By promoter region cloning,mutagenesis,transient transfection and luciferase assay,we found one novel cis-regulatory element,rs294775.The relative promoter activity of C allele,is-25.5%lower than that of T allele(P<0.001)By chromatin immunoprecipitation(ChIP),we verified that this mutation located within the binding site of transcript factor ELK1(ETS transcription factor).Our effort scrutinized the expression regulation mechenism and provide a basis for further pharmacogenetics and disease genetics.Part Ⅱ:Lung cancer is one of the most common malignancies in the world and is the main cause of death worldwide.The morbidity and mortality of lung cancer is growing rapidly,which cause a serious threat to public health and human life.Numerous studies have now shown that genetic factors affect the development and progression of lung cancer.TGM5 gene encodes a member of the transglutaminase family.Recent genome-wide association study(GWAS)found that the mutation rs748404 in TGM5 promoter was significantly correlated with lung cancer.But its regulatory mechanism and the role in lung cancer is not known.Therefore,the study of TGM5 expression regulation mechanism will further highlight the prevention and treatment of lung cancer.By molecular cloning of TGM5 promoter region,mutagenesis,transient transfection and luciferase assay,we observed that neither rs748404 nor another SNP,rs 12911132,in linkage disequilibrium(LD)with it,can alter the relative promoter activity,thus indicating that both of them are not the causal SNP for lung cancer.By analyzing the 1000 genomes plan data,we identified another four SNPs,rs35535692,rs66651343,rs12909095 and rs17779494,in LD with rs748404,which may exert their function by enhancer model.Through functional genomics approaches,we found that three of them,rs17779494,rs66651343 and rs12909095,can alter the relative enhancer activity(P=0.0004,0.003,0.0006,respectively).The most noticeable one was rs1290909,the T allele of which showed 142 fold relative enhancer activity than C allele.Further ChIP and chromatin conform capture are still in progress.