Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA.
Biol Reprod. 2021 Mar 11;104(3):684-694. doi: 10.1093/biolre/ioaa228.
Among a wide diversity of sexually reproducing species, male ejaculates coagulate to form what has been termed a copulatory plug. A number of functions have been attributed to copulatory plugs, including the inhibition of female remating and the promotion of ejaculate movement. Here we demonstrate that copulatory plugs also influence the likelihood of implantation, which occurs roughly 4 days after copulation in mice. Using a bead transfer method to control for differences in ejaculate retention and fertilization rates, we show that implantation rates significantly drop among females mated to genetically engineered males incapable of forming plugs (because they lack functional transglutaminase 4, the main enzyme responsible for its formation). Surprisingly, this result does not correlate with differences in circulating progesterone levels among females, an important hormone involved in implantation. We discuss three models that connect male-derived copulatory plugs to implantation success, including the hypothesis that plugs contribute to a threshold amount of stimulation required for females to become receptive to implantation.
在广泛的有性生殖物种中，雄性精液会凝结形成所谓的交配栓。交配栓具有多种功能，包括抑制雌性再次交配和促进精液运动。在这里，我们证明交配栓还会影响着床的可能性，着床通常发生在交配后大约 4 天的小鼠体内。我们使用珠子转移方法来控制精液保留和受精率的差异，结果表明，与不能形成栓的基因工程雄性（因为它们缺乏形成栓的主要酶——转谷氨酰胺酶 4）交配的雌性，其着床率显著下降。令人惊讶的是，这一结果与雌性循环中的孕激素水平差异无关，孕激素是着床过程中一种重要的激素。我们讨论了将雄性产生的交配栓与着床成功联系起来的三种模型，包括栓有助于刺激雌性接受着床的假说。
