PTX3, a member of the pentraxin protein family, plays important roles in ovulation as a marker of cumulus cell–oocyte complex expansion. However, the expression and function of PTX3 in goat ovarian GCs remain unclear. We isolated GCs from small and large follicles and found that PTX3 expression was significantly decreased and miR-29 mRNA expression was significantly increased during the growth of antral follicles. MiR-29 decreased PTX3 expression by targeting its 3′ untranslated. Furthermore, miR-29 promoted GC proliferation, suppressed steroidogenesis and apoptosis by targeting PTX3 via the activation of the PI3K/AKT/mTOR and Erk1/2 signaling pathways. Treatment with inhibitors also verified these results. Meanwhile, we found that PI3K/AKT/mTOR and Erk1/2 signaling pathways had different role in secretion of E2 and P4 by regulating differently various steroidogenic enzyme (CYP19A1, CYP11A1, StAR and HSD3B) expression. These outcomes indicate the potential role of PTX3 in goat follicular growth and atresia.

PTX3是pentraxin蛋白家族的成员，在排卵中起着重要的作用，作为卵丘-卵母细胞复合物扩增的标志物。但是，PTX3在山羊卵巢GC中的表达和功能仍不清楚。我们从大小卵泡中分离出GC，发现在肛门卵泡生长期间PTX3表达显着降低，而miR-29 mRNA表达显着增加。MiR-29通过靶向未翻译的3'降低PTX3表达。此外，miR-29通过靶向PTX3促进GC增殖，抑制类固醇生成和细胞凋亡。通过激活PI3K / AKT / mTOR和Erk1 / 2信号通路。用抑制剂治疗也证实了这些结果。同时，我们发现PI3K / AKT / mTOR和Erk1 / 2信号通路通过调节不同的类固醇生成酶（CYP19A1，CYP11A1，StAR和HSD3B）表达在E2和P4的分泌中具有不同的作用。这些结果表明PTX3在山羊卵泡生长和闭锁中的潜在作用。