CCND2在雌性牦牛生殖轴系中的表达分布

The Expression and Distribution of CCND2 in Reproductive Axis of Female Yak

细胞周期蛋白CCND2(Cyclin-D2)是细胞增殖和细胞周期中G1/S期转变的关键调控因子,在癌症、营养代谢以及卵泡发育中参与调控。为研究CCND2在雌性牦牛(Bos grunniens)生殖轴系(HPOA轴)中的表达分布及其对季节性繁殖的作用机制,选取健康发情期雌性牦牛的下丘脑、垂体、卵巢组织,采用实时荧光定量PCR(qRT-PCR)检测CCND2基因在牦牛下丘脑、垂体、卵巢等组织中的表达情况;此外利用免疫组织化学(Immunohistochemistry,IHC)技术对CCND2基因所编码的蛋白表达分布情况进行检测。结果表明,CCND2基因在牦牛HPOA轴各组织中共表达,在下丘脑中的表达量显著高于垂体和卵巢组织(P<0.05);免疫组化结果显示,CCND2蛋白在牦牛卵巢颗粒细胞中呈强阳性表达,在垂体的嗜碱性细胞和嗜酸性细胞中均有阳性反应,在下丘脑颗粒细胞和锥体细胞中也呈现出不同程度的表达情况。提示CCND2在雌性牦牛生殖轴系中存在一定的调控作用,可能通过参与卵泡发育和排卵进程从而对牦牛季节性繁殖产生影响。

Cyclin-D2 protein is a key regulator of cell proliferation and G1/S transition in the cell cycle,and is involved in the regulation of cancer,nutrient metabolism and follicular development.The objective of this study is to explore the expression of CCND2 in reproductive axons of female yak(Bos grunniens)and regulation mechanism on seasonal reproductive.The samples of hypothalamus,pituitary and ovarian of adult healthy female yak during rut were collected.The hypothalamic-pituitary-ovarian reproductive axis(HPOA)expression characteristics of yak CCND2 gene were detected by real-time fluorescence quantitative PCR.Furthermore,the expression characteristics of yak CCND2 protein were detected by immunohistochemistry(IHC).The results showed that CCND2 mRNA were expressed in hypothalamus,pituitary and ovary of yak,and the expression level in hypothalamus was significantly higher than in ovary and pituitary(P<0.05).Immunohistochemistry results showed that CCND2 protein was strongly positive in ovarian granulosa cells.Both basophilic cell and acidophilic cell of the pituitary gland had positive reactions.Different levels of expression were also shown in granular cells and pyramidal cells of hypothalamus.These results suggest that CCND2 plays a regulatory role in female yak reproductive axis,and may affect the seasonal reproduction of yaks by participating in follicular development and ovulation.