Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, 611130, China.
National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China.
Theriogenology. 2022 Sep 15;190:52-64. doi: 10.1016/j.theriogenology.2022.07.019. Epub 2022 Aug 3.
The normal development of follicles determines the reproductive performance of females. Granulosa cells (GC) play crucial roles in follicular maturation. Numerous studies have shown that miRNAs are involved in the regulation of GC. According to our previous sequencing data, gga-miR-146b-3p was differentially expressed in normal and atretic chicken follicles. In this study, we verified that gga-miR-146b-3p attenuated proliferation and autophagy but promoted apoptosis in chicken GC. Threonine kinase1 (AKT1), a key member of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, was predicted to be a target gene of gga-miR-146b-3p via bioinformatic analysis. Dual-luciferase reporter gene assays were used to determine target relationships. Moreover, knockout of AKT1 decelerated proliferation and autophagy while accelerating the apoptosis of GC. However, overexpression of AKT1 reversed these results. In summary, our results demonstrated that gga-miR-146b-3p repressed the proliferation and autophagy of chicken GC while up-regulating apoptosis by targeting AKT1 through the PI3K/AKT signaling pathway. These findings may provide great insights for further exploration of the molecular regulation of gga-miR-146b-3p and AKT1 on the functions of GC during folliculogenesis.
卵泡的正常发育决定了雌性动物的生殖性能。颗粒细胞（GC）在卵泡成熟中发挥着关键作用。大量研究表明，miRNA 参与了 GC 的调控。根据我们之前的测序数据，gga-miR-146b-3p 在正常和闭锁鸡卵泡中表达差异。在这项研究中，我们验证了 gga-miR-146b-3p 可减弱鸡 GC 的增殖和自噬，但促进其凋亡。丝氨酸/苏氨酸激酶 1（AKT1）是磷脂酰肌醇 3-激酶（PI3K）/AKT 信号通路的关键成员，通过生物信息学分析预测其为 gga-miR-146b-3p 的靶基因。双荧光素酶报告基因检测用于确定靶基因关系。此外，AKT1 的敲除会减缓 GC 的增殖和自噬，但会加速其凋亡。然而，AKT1 的过表达则逆转了这些结果。综上所述，我们的研究结果表明，gga-miR-146b-3p 通过 PI3K/AKT 信号通路靶向 AKT1 抑制鸡 GC 的增殖和自噬，同时上调其凋亡。这些发现可能为进一步探索 gga-miR-146b-3p 和 AKT1 在卵泡发生过程中对 GC 功能的分子调控提供重要线索。
