Expression And Distribution Research Of Melatonin Receptors MT₁and MT₂in Ovary Of Female White Yak In Breeding Season

Melatonin is a neurohormone which regulates the reproductive physiology ofmammals via the MT1and MT2melatonin receptor. Therefore, melatonin act the role ofthe regulation of ovarian follicle development mediated by the distribution of melatoninreceptors on the ovaries directly. White yak is a kind of rare yak species living harshnatural conditions with cold and low oxygen. So far, it have not yet been clarifiedmelatonin receptor distribution in the white yak ovaries, melatonin receptor geneexpression patterns in white yak ovaries and mechanism of melatonin regulatereproductive hormone in white yak ovaries.Therefore, this study chose the female white yak. Using molecular biologytechnology of cloning, immunohistochemistry and realtime PCR methods, it make apreliminary studies for distribution of yak melatonin receptor subtype in ovaries, cloningand expression of melatonin receptor genes. The results were as follows:1Molecular characteristics Cloning ovarian melatonin receptors subtypes MT1(843bp) and MT2(411bp) gene sequence of white yak successfully. Comparing thehomologous sequence with other melatonin receptor gene of animals found that MT1inwhite yak and buffalo are closed95.6%; MT2gene sequence is most similar to pigs.Predicting and comparative analysis of melatonin by the white yak gene encoded proteinpeptide found that white yak proteins of MT1and MT2receptors belong to the Gprotein-coupled receptor family, and the MT1and MT2gene in white yaks were notreported.2Distribution of melatonin receptors Immunohistochemical results showed that itis different in location and expression of MT1and MT2receptors in white yak ovarian, buta high expression level indicated that melatonin play a physiological role in the regulationof ovarian process. There are both synergistic effect and different independent regulatoryfunction in MT1and MT2.3Different expression between organizations Using the real-time PCR methods tostudy the differences of MT1and MT2mRNA expression in pregnant white yak ovarianand luteal tissue. The expression of MT1and MT2mRNA in the corpus luteum werehigher than the ovary, and the expression of luteal MT1mRNA in significantly higher than the ovary, and MT2were no significant differences.This study, first reported part of white yak MT1and MT2gene sequences andexplored the expression and distribution of white yak ovaries during pregnancy, which isprovided a theoretical basis for the regulation of melatonin on the reproductive and othermammals physiological mechanism of action.