中文摘要：

【目的】研究湖羊卵巢组织BMP2、BMP4、BMP6和BMP7基因mRNA表达水平与排卵数的相关性,筛选影响湖羊多胎性状的候选基因,为揭示湖羊高繁多胎分子遗传机理提供参考。【方法】选取16只经产湖羊母羊,分为产单羔组和多羔组,发情后24～36h屠宰,取卵巢,计数排卵点,记录排卵数;应用RT-PCR技术检测BMP2、BMP4、BMP6和BMP7基因的组织表达特征,进一步利用实时荧光定量PCR技术分析各基因mRNA在单羔组和多羔组卵巢组织中的表达差异。【结果】BMP2、BMP4和BMP7基因在湖羊母羊卵巢组织内表达,而且在垂体及下丘脑、子宫、心脏、肝脏、脾脏、肺脏、肾脏、肌肉、输卵管组织中均有表达;BMP6基因仅在湖羊母羊卵巢、肾脏、肌肉和输卵管组织中表达。在卵巢组织,多羔组排卵数极显著高于单羔组（P〈0.01）,且多羔组BMP4基因mRNA表达极显著高于单羔组（P〈0.01）,而BMP2、BMP6和BMP7基因mRNA表达在单羔组和多羔组间无显著差异（P〉0.05）;相关分析表明在卵巢组织中,只有BMP4基因mRNA表达与排卵数呈正相关（r=0.741,P〈0.05）。【结论】BMP4基因mRNA表达在单羔组和多羔组间差异显著,可能对湖羊排卵数起关键作用,是影响湖羊排卵数的候选基因。

英文摘要：

【Objective】 The present study was performed to investigate the relationships between the mRNA level of BMP2,BMP4,BMP6 and BMP7 gene in ovaries and the ovulation number in Hu sheep,so as to provide references for finding hyper-prolificacy candidate gene and understanding the molecular genetic mechanism of high fecundity in Hu sheep. 【Method】 Sixteen adult Hu ewes,classified as the single lambling （S） or multiple lambling （M） group,were sacrificed for tissue sampling and ovulation number counting between 24-36h after estrus diagnosis. The tissue distributions of BMP2,BMP4,BMP6 and BMP7 mRNA were detected by RT-PCR and the gene expression levels in the ovaries were investigated by real-time PCR. 【Result】 BMP2,BMP4 and BMP7 mRNA exited in the ovary and other tissues,including hypothalamus,pituitary,uterus,heart,liver,spleen,lung,kidney,muscle and oviduct,but BMP6 mRNA was only detected in the ovary,kidney,muscle and oviduct. The expression level of BMP2,BMP6 and BMP7 mRNA in the ovary did not differ between S and M group （P〉0.05）,but BMP4 mRNA abundance in the ovary was extremely higher in M group than that in S group （P〈0.01）. Bivariate correlation analysis showed that BMP4 mRNA expression in the ovary was positively correlated with ovulation number （r = 0.741,P〈0.05）,but there was no correlation between the mRNA expression level of BMP2,BMP6 or BMP7 and the ovulation number （P〉0.05）. 【Conclusion】 The results suggested that BMP4 might play a key role in ovulation number and might be a candidate gene for high fecundity in Hu sheep.