The effects of FAR1 and TGFBRAP1 on the proliferation and apoptosis of follicular granulosa cells in goose (Anser cygnoides).

The low laying performance of geese seriously damages the growth of the poultry industry, and is related to the development of pre- hierarchical follicles. Our previous studies have revealed that FAR1 and TGFBRAP1 were involved in follicular development, but the exact regulation mechanism still kept unclear. In recent studies, the expression of FAR1 and TGFBRAP1 mRNA were detected, and we found that their expression levels were relatively higher in hierarchical follicles than in pre-hierarchical follicles (P < 0.05). Moreover, generally the level of FAR1 and TGFBRAP1 mRNA gradually increased in hierarchical follicles. In addition, the proliferation and apoptosis of granulosa cells were assayed with overexpression or knockdown technology. The results showed that by the knockdown of FAR1 mRNA level, the proliferation rate of follicular granulosa cells increased significantly, the apoptosis rate decreased (P < 0.05), and the apoptosis rate also reduced obviously by transfecting TGFBRAP1-siRNA (P < 0.05). Finally, the overexpression of FAR1 or TGFBRAP1 resulted in the inhabitation to the secretion of E2 and P4 in granulosa cells, while the knockdown of FAR1 or TGFBRAP1 enhanced the secretion of E2 and P4. In conclusion, the results indicated that FAR1 and TGFBRAP1 regulated the apoptosis of follicular granulosa cells and cut the secretion of E2 and P4 in geese, which provided basic data for the understanding of the regulating process of goose reproduction.