Generation And Phenotypic Analysis Of The Knockout Mice Of Zinc Finger Protein ZBTB45

BACKGROUNDThe proteins comprising the zinc finger domain are called zinc finger proteins. Theyare one of the biggest transcription factor families in eukaryotes. As the most abundantprotein motifs, zinc finger proteins are ubiquitous in mammalian cells. In the humangenome, nearly2percent of the sequences, about as many as hundreds of genes couldencode zinc finger proteins, and they play a vital role in the body’s activities. Currently, theresearch about zinc finger proteins focuses on the screening and regulation mechanism ofthe target molecules.The transcription factor ZBTB20is widely expressed in various tissues in vivo,especially the brain, liver, pancreas, muscles, etc. It is involved in the process oftranscription and translation, regulating the body’s growth and development, energymetabolism, etc and plays crucial roles in vivo. The ZBTB20gene knockout mouse modelshows extremely serious physical defects: significant disorders to growth and development,not surviving to adulthood, high mortality rate, unusually severe lipid disorders.Homologous comparison data shows that ZBTB45has the highest homology withZBTB20. Their consistency in protein is up to43.5%, and their consistency in BTBdomain and C2H2zinc finger domain is even up to68%.With the development of gene knockout technology, the establishment of geneknockout mouse model is possible and is becoming an indispensable tool for studying genefunction. Therefore, we could establish the ZBTB45gene knockout mice model byhomologous recombination technology and Cre-LoxP recombinase system. This provide agood animal model for the study of ZBTB45gene functions.OBJECTIVEEstablish the ZBTB45knockout mouse model by gene knockout technology and bythe analysis of the phenotypes of ZBTB45knockout mice, provide a experimental methodsfor the further research of the potential physiological function and regulation mechanismsfor the ZBTB45gene in vivo. METHODSEstablish the ZBTB45knockout mice model by homologous recombinationtechnology and Cre-LoxP recombinase system and prove the successful mouse model bydetecting the levels of DNA, RNA of the KO mice. Adult male mice are selected for thestudy and the heterozygous and wild type mice as littermate control. We will observe thedata containing the body weight curve,daily-food-intake standardized by body weight, fedglucose level, fasting glucose level, oral glucose tolerance test(OGTT), plasma lipids levelsetc to search the potential physical functions of ZBTB45gene in ongeny, glucose and lipidmetabolism.RESULTSWe have established ZBTB45knockout mice model for the first time by using thegene knockout technology, and the establishment of mouse model proved successful in thelevels of DNA and RNA. Though the analysis of some phenotypes of the ZBTB45knockout mice and the littermate controls, we observe that the growth and development ofZBTB45knockout mice are normal and their fertility is not affected by the absence ofZBTB45gene. We detected the daily-food-intake standardized by body weight and thebody weight curve between the ZBTB45knockout mice and the littermate controls. Butour data do not show differences which we expected. The analysis of fasting glucose leveland oral glucose tolerance test does not show statistically difference either. The plasmatriglyceride(TG) and cholesterol(TC) levels of ZBTB45knockout mice have no significantchanges when compared with the wide type controls.CONCLUSIONThough the analysis of some phenotypes of the ZBTB45knockout mice,we observethat the growth and development of the ZBTB45knockout mice are normal and they donot have the glucose and lipids metabolism disorders when compared with the wild typemice. The oral glucose tolerance test (OGTT) showed that the ZBTB45knockout mice alsohad no significant differences when compared with the littermate controls. Therefore, wereason that ZBTB45gene may not participate in the regulation of growth, development,glucose metabolism and lipids metabolism or that the disorders resulting from the absenceof ZBTB45in mice are not enough to cause corresponding changes in phenotype. But itneeds to be confirmed by further experiments because of the insufficient evidence.