Department of Dairy Science, University of Wisconsin-Madison, Madison 53706, USA.
J Dairy Sci. 2009 Dec;92(12):6186-91. doi: 10.3168/jds.2009-2439.
Infertility is a major cause of dairy cow culling and economic loss. Signal transducer and activator of transcription (STAT) proteins are transcription factors that play an important role in fertility and early embryonic development, among many other functions. Previous studies have reported the association of several genes from the JAK/STAT signaling pathway with fertility traits in cattle. The STAT1 and STAT3 genes are members of this pathway and are known to interact with each other by forming a heterodimer complex that enters the nucleus and controls expression of specific genes. Thus, the objective of this study was to investigate the effects of the interactions between polymorphisms in these genes on fertilization and early embryonic survival rates using an in vitro fertilization system. A total of 7,519 oocytes, collected from 445 ovaries, were exposed to sperm and a total of 5,075 embryos were produced. Fertilization rate was calculated as the number of cleaved embryos at 48 h post-fertilization out of the total number of oocytes exposed to sperm. Early embryonic survival rate of embryos was calculated as the number of blastocysts on d 7 of development out of the total number of embryos cultured. Effects of ovary genotypes on fertilization and early embryonic survival rates were evaluated. Single-SNP analysis revealed a statistically significant association between SNP25402 in STAT3 and fertilization rate. Oocytes produced from ovaries with AA genotype showed a 0.701 fertilization rate versus 0.666 and 0.663 for oocytes produced from AC and CC ovaries, respectively. The interaction between STAT3 SNP (SNP19069/SNP25402) was highly significant for survival rate but not for fertilization rate. Also, the interaction between STAT1 SNP and SNP19069 was highly significant for survival rate. Genotype combinations found to promote fertilization and embryonic survival could be incorporated into breeding programs aimed at improving fertility performance in dairy cattle.
不孕是奶牛淘汰和经济损失的主要原因。信号转导子和转录激活子（STAT）蛋白是转录因子，在生育能力和早期胚胎发育等许多其他功能中发挥重要作用。先前的研究报告了 JAK/STAT 信号通路中的几个基因与牛的生育力特征之间的关联。STAT1 和 STAT3 基因是该途径的成员，已知它们通过形成异二聚体复合物进入细胞核并控制特定基因的表达来相互作用。因此，本研究旨在使用体外受精系统研究这些基因中的多态性之间的相互作用对受精和早期胚胎存活率的影响。共收集了来自 445 个卵巢的 7519 个卵母细胞，并使其与精子接触，共产生了 5075 个胚胎。受精率计算为受精后 48 小时内分裂胚胎的数量与暴露于精子的卵母细胞总数的比值。早期胚胎存活率计算为发育第 7 天的囊胚数量与培养胚胎总数的比值。评估了卵巢基因型对受精和早期胚胎存活率的影响。单核苷酸多态性分析显示，STAT3 中的 SNP25402 与受精率之间存在统计学显著关联。AA 基因型卵巢产生的卵母细胞的受精率为 0.701，而 AC 和 CC 基因型卵巢产生的卵母细胞的受精率分别为 0.666 和 0.663。STAT3 SNP（SNP19069/SNP25402）之间的相互作用对存活率有很高的显著影响，但对受精率没有影响。此外，STAT1 SNP 和 SNP19069 之间的相互作用对存活率有很高的显著影响。发现促进受精和胚胎存活的基因型组合可以纳入旨在提高奶牛生育能力的育种计划中。
