湖羊TGF-β1基因特征、表达及其与排卵数的相关性分析

【目的】获取湖羊TGF-β1基因序列，了解TGF-β1序列特征和组织表达特征，分析卵巢组织中TGF-β1基因表达水平与排卵数之间的关系。【方法】通过PCR扩增和测序获得湖羊TGF-β1基因序列，并采用生物信息学方法分析其序列特征；采用RT-PCR分析湖羊TGF-β1基因的组织表达特征；采用Real-time qPCR方法分析多羔组与单羔组湖羊卵巢组织TGF-β1基因表达水平的差异，及其与排卵数之间的关系。【结果】湖羊TGF-β1基因编码区序列全长1 173 bp，编码蛋白含有390个氨基酸残基，包含典型的TGF-β前肽和TGF-β like等结构域。TGF-β1基因在湖羊卵巢组织中高表达，多羔组卵巢组织中TGF-β1基因表达水平显著高于单羔组（P＜0.05），且表达水平与排卵数呈极显著正相关（P＜0.01）。【结论】多羔组湖羊卵巢组织TGF-β1基因表达水平显著高于单羔组，且与排卵数间呈极显著正相关，推测TGF-β1基因在湖羊卵泡发育、成熟或排卵过程中发挥重要作用，是影响湖羊高繁殖力的候选基因。

Characterization,Expression of TGF-β1 Gene and Its Association with Ovulation Rate in Hu Sheep

【Objective】 The present study was performed to clone the TGF-β1 sequence in Hu sheep and to comprehend the sequence character of Hu sheep so as to investigate the relationships between the mRNA level of TGF-β1 gene and ovulation number in ovaries of Hu sheep. 【Method】The sequence of TGF-β1 in Hu sheep was cloned and sequenced, and the sequence was analyzed by bioinformatics. The tissue distributions of TGF-β1 were detected by RT-PCR, and the gene expression level differences in the ovaries between the high- and the low-fecundity groups and the relationships with the ovulation rate were detected by real-time qPCR.【Result】The length of TGF-β1 gene coding sequence was 1 173 bp, encoding 390 amino acids which include some typical domains such as TGF-β propeptide and TGF-β like. RT-PCR assays revealed that TGF-β1 highly expressed in the ovary tissue. The ovarian mRNA expression level of TGF-β1 in high-fecundity group was significantly greater than that in low-fecundity group (P＜0.05), and mRNA expression level was significantly positively correlated with ovulation rate (P＜0.01). 【Conclusion】The ovarian mRNA expression level of TGF-β1 in high-fecundity group was significantly greater than that in low-fecundity group and significantly positively correlated with ovulation rate. These findings indicate that TGF-β1 of Hu sheep play an important role in follicular development, maturation or ovulation, which probably is associated with high fecundity of Hu sheep.