Female birds skew offspring sex ratios based on environmental and social stimuli; however, the mechanism mediating this phenomenon remains unknown. Growing evidence suggests that testosterone and corticosterone may influence meiosis, as they skew sex ratios when given immediately before chromosomal segregation. It is unclear if these hormones act on the germinal disc (GD) or through a downstream mediator. It is also unknown whether the GD contains receptors for these hormones. If testosterone and/or corticosterone act on the GD to skew sex ratios, then the GD should have receptors for them and that receptor levels should be higher in the GD regions compared to other follicular regions. Furthermore, fluctuations of receptor levels should occur near meiotic segregation. We collected ovarian follicles at 5 h pre-ovulation (just before meiotic segregation) and 20 h pre-ovulation (when sex chromosomes are arrested), and measured androgen receptor (AR) and mineralocorticoid receptor (MR) protein levels via Western blot. ARs and MRs were on the follicle in the GD and non-GD regions, and at 5 h and 20 h pre-ovulation. Both AR and MR protein levels were higher in the GD region than the non-GD region at both time points, but did not differ between time points. These results suggest that hen ovarian follicles have receptors for testosterone and corticosterone, and that the ability for testosterone to respond may be specifically higher in the GD-region, providing further support for the role of testosterone in the alteration of meiotic segregation.

译文

雌鸟根据环境和社会刺激使后代性别比偏斜; 但是,介导这种现象的机制仍然未知。越来越多的证据表明,睾丸激素和皮质酮可能会影响减数分裂,因为它们在染色体分离之前立即给予时会扭曲性别比。尚不清楚这些激素是否作用于生发盘 (GD) 或通过下游介质起作用。还不清楚GD是否包含这些激素的受体。如果睾丸激素和/或皮质酮对GD与偏斜性别比起作用,则GD应具有受体,并且与其他卵泡区域相比,GD区域的受体水平应更高。此外,受体水平的波动应在减数分裂分离附近发生。我们在排卵前5小时 (减数分裂分离之前) 和排卵前20小时 (性染色体停滞时) 收集了卵巢卵泡,并通过Western blot测量了雄激素受体 (AR) 和盐皮质激素受体 (MR) 蛋白水平。ARs和MRs在GD和非GD区域以及排卵前5 h和20 h位于卵泡上。在两个时间点,GD区域的AR和MR蛋白水平均高于非GD区域,但在时间点之间没有差异。这些结果表明,母鸡卵巢卵泡具有睾丸激素和皮质酮的受体,并且睾丸激素在GD区域的反应能力可能更高,这进一步支持了睾丸激素在减数分裂分离改变中的作用。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录