Wilms' tumor gene WT1 encodes a nuclear transcriptional factor, which has been shown to regulate granulosa cell steroidogenesis in bovine; however, it is not known whether the functions of theca cells are regulated by WT1. Here, we determined the effects of this gene on theca cell proliferation, apoptosis, and steroidogenesis in vitro. In cultured bovine theca cells, the downregulation of WT1 increased the secretion of progesterone but had no effect on proliferation and apoptosis. WT1 includes the variants WT1(+KTS) and WT1(−KTS), which differ by 3 amino acids KTS (lysine, threonine, and serine). WT1(±KTS) upregulation increased the messenger RNA (mRNA) expression of STAR and CYP17A1 and decreased the progesterone secretion and CYP11A1 mRNA expression. In contrast to WT1(+KTS), WT1(−KTS) upregulation also decreased the mRNA expression of 3β-HSD. In both variants, WT1(−KTS) has more obvious effects. In conclusion, WT1 can decrease progesterone secretion, likely due in part to the inhibition of CYP11A1 and 3β-HSD.

Wilms 的肿瘤基因 WT1 编码一种核转录因子，该因子已被证明可调节牛的颗粒细胞类固醇生成；然而，尚不清楚theca细胞的功能是否受WT1调节。在这里，我们确定了该基因对体外膜细胞增殖、凋亡和类固醇生成的影响。在培养的牛膜细胞中，WT1 的下调增加了孕酮的分泌，但对增殖和凋亡没有影响。WT1 包括变体 WT1(+KTS) 和 WT1(-KTS)，它们的区别在于 3 个氨基酸 KTS（赖氨酸、苏氨酸和丝氨酸）。WT1(±KTS) 上调增加了 STAR 和 CYP17A1 的信使 RNA (mRNA) 表达并降低了孕酮分泌和 CYP11A1 mRNA 表达。与WT1(+KTS)相比，WT1(-KTS) 上调也降低了 3β-HSD 的 mRNA 表达。在这两种变体中，WT1(-KTS) 具有更明显的效果。总之，WT1 可以减少孕酮分泌，部分原因可能是抑制了CYP11A1和3β-HSD。