Expression And Regulation Mechanism Of Porcine Oneset Related Genes TAC3

Neurokinin B(NKB) belongs to the tachykinin family, encoded by the TAC3(Tachykinin3,TAC3)gene.Neurokinin B cooperates with Kisspeptin and dynorphin A induceing puberty in sow. Neurokinin B is an essential signal for the Hypothalamus-Pituitary-Gonad(HPG axis) control puberty through expedite Gn RH releasing. loss-of-function mutation in NKB or its receptor NK3 R lead to hypogonadotropic hypogonadism which is a pathological condition of impuberism and infertility of central origin, manifested Gn RH secretion disordersed and failed to activate puberty. When administered to animals exogenous NKB elevated serum levels of LH and FSH, senktide an NK3 R agonist also modulate LH and FSH secretion.NKB is a key factor to star puberty. In this study, we analysis of TAC3 gene expression regulation mechanism, explore regulation of estrogen on TAC3 gene. It provides a reference to explore the molecular mechanisms of puberty start.we analyzed NKB expression in HPG axis in pubertal timing.Cloned 5 'regulatory region of TAC3 gene and detected its promoter activity, defined transcription factor C/EBP?,YY1 and ESR through bioinformatics website and Ch IP. In order to verify function of transcription factor we applied overexpression and si RNA regulation of TAC3 were analyzed in porcine ovarian granulosa cells. First, we overexpred C/EBP?,YY1 and quantified expression of TAC3. Second, we transfected si RNA to inhibite transcription factor and quantified expression of TAC3. Third, we applied co-transfection with transcription factor and promoter dual luciferase reporter vector detected its promoter activity. Finally, we treated ovarian granulosa cells with estrogen and quantified expression of TAC3. We deleted TAC3 promoter sequences for combineing ESR and detected its promoter activity.The results are as follows:(1) TAC3 gene have higher expression in prepuberty than prepuberty in HPG axis, TAC3 gene expression decresed in postpuberty in Hypothalamus and ovary;(2) Cloned TAC3 gene promoter-2815/+129 which full legth is 2943 bp. The the region-882 /-544 of TAC3 gene promoter may have positive regulatory elements binding site,the the region-1633/-2482 may have negative regulatory element binding sites;(3) The region-653/-639 of TAC3 gene promote exist C/EBP? binding site, C/EBP?binding to C/EBP? binding site where exist in-653/-639 of TAC3 gene promote promote transcription and expression of TAC3;(4) The region-873/-856 of TAC3 gene promote exist YY1 binding site; YY1 binding to YY1 binding site where exist in-873/-856 of TAC3 gene may promote transcription and expression of TAC3;(5) Estrogen inhibit expression of TAC3 gene,when delete estrogen reseponse element the region-2122/-2112 of TAC3 gene promote estrogen does not woker.This study was the following conclusions:Transcription factor C/EBP? bingding to promoter of TAC3 gene to promoting the expression of genes. Transcription factor YY1 may promoting the expression of genes.estrogen bingding to estrogen response element of TAC3 gene and inhibiting transcription of the gene.