绵羊母体VA调控子代肌纤维发育及卫星细胞活性的研究

母体营养物质供给对胎儿肌纤维发育至关重要。维生素A（VA）在哺乳动物器官发生中起关键作用，绵羊母体VA水平对胎儿肌纤维发育、卫星细胞活性及子代产肉性能的影响及机制尚不明确。本项目拟建立母体VA差异模型，母羊经同期发情后人工授精。获取胎儿期（E115天）、初生、断奶及6月龄骨骼肌样品，采用Trichrome染色、免疫组化、qRT-PCR等方法分析母体不同VA水平对胎儿及子代肌纤维数目、类型及大小等影响，并揭示其与产肉性能及肉品质的关系。分离并培养胎儿趾长伸肌单肌纤维，采用免疫荧光及激光共聚焦技术研究母体VA对胎儿卫星细胞数目的影响。分离并纯化胎儿卫星细胞，研究视黄酸对卫星细胞体外增殖及成肌分化的影响，并深入阐明其调控机制。研究结果对揭示绵羊母体VA调控子代骨骼肌发育具有重要意义，可为提升肉羊产肉性能的调控提供新思路。

Maternal nutrition supply during pregnancy affects fetal skeletal muscle fiber development. Vitamin A (VA) plays important role in mammalian organogenesis, whether maternal VA affects fetal skeletal muscle fiber development and satellite cell activity remain unclear. In the present project, we will establish an ewe model that supplemented with different level of dietary VA. All ewes will undergo estrous synchronization and artificial insemination. The skeletal muscles from fetal (E115), birth, wean and 6-month age stages will be sampled, and trichrome staining, immunohistochemistry and qRT-PCR will be used to determine the effect of maternal VA on fiber numbers, types and size distributions. Meanwhile, the correlation between maternal VA level and lamb’s meat production ability will be analyzed. Fetal single EDL muscle fiber will be isolated and cultured, and the number of satellite cell in different groups will be determined using IHC and LSCM. Moreover, satellite cells will be isolated and purified, and both the role and mechanisms of retinoic acid on satellite cell proliferation and differentiation will be explored. Our study will reveal the effects of maternal VA on offspring’s skeletal muscle development, and provide novel perspective for lamb industry aiming at improvement of meat production efficiency through manipulation of maternal dietary VA supplementation.