该研究通过免疫组化和QRT-PCR等方法系统分析了Gas6(growth arrest-special gene 6)基因在猪卵泡发生及早期胚胎发育过程中的表达规律,并提出了一种改良猪卵母细胞体外成熟系统的方法。研究结果显示,Gas6基因表达于猪卵巢中的卵母细胞细胞核及其周围的卵丘细胞,在卵母细胞体外成熟及早期胚胎发育过程中始终有表达,且在囊胚中表达最高。Gas6 mRNA在卵母细胞成熟过程中始终存在,但在孤雌激活后迅速消失,直到发育到囊胚时再次出现。在猪卵母细胞体外培养系统中添加不同浓度的Gas6重组蛋白培养卵母细胞,发现添加Gas6重组蛋白对卵母细胞的极体率无显著影响;但是当添加浓度为100 ng/mL时,培养的卵母细胞孤雌激活后分裂率、囊胚率及囊胚细胞数都显著增高。Gas6可能是通过改善卵母细胞细胞质的成熟质量提高卵母细胞的发育潜能,从而获得了更多、更好的胚胎。
The expression pattem of Gas6 gene in porcine oocytes and early embryo was analyzed systematically using immunohistochemistry and QRT-PCR, and a new method was proposed to improve the quality of in vitro matured pig oocytes. The results showed that Gas6 gene was localized in ovarian oocyte nucleus and the surrounding cumulus cells simultaneously. It expressed all through the in vitro maturation of oocytes, and reached the highest relative expression peak in the blastocyst stage. Gas6 mRNA existed in the process of in vitro matured oocytes continuously, but disappeared after parthenogenetic activation, reappeared until the blastocyst stage. By adding recombinant Gas6 protein into the in vitro matured media of pig oocytes, we found that there was no sig- nificant change to the poly body discharge rate of the in vitro matured oocytes, but the cleavage rate, blastocyst rate and blastocyst cells number of oocytes after parthenogenetic activation was significantly increased when the addingconcentration reached 100 ng/mL. We predicted that Gas6 increased the development potential of oocytes by improving the quality of oocytes cytoplasm maturation, so as to obtain more and better embryos.