Bloch Qazi Margaret C, Wolfner Mariana F
Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
J Exp Biol. 2003 Oct;206(Pt 19):3521-8. doi: 10.1242/jeb.00585.
Female sperm storage is an essential component of reproduction in many animals. In insects, female sperm storage affects fecundity, sperm competition/preference and receptivity to re-mating. Female sperm storage consists of several stages, including sperm entry into the sperm storage organs (SSOs), maintenance within the SSOs and exit from the SSOs. The Drosophila melanogaster male seminal protein Acp36DE is essential for female sperm storage. Acp36DE associates with sperm and localizes to specific regions of the female reproductive tract, including the SSOs. We determined the stage of sperm storage at which Acp36DE acts by comparing the timing of initial sperm entry into storage as well as the rates of sperm accumulation and release from the SSOs in the presence or absence of Acp36DE. Acp36DE accelerates sperm accumulation into storage but does not mediate the entry of the first sperm into storage. This finding also demonstrates that the initial stage of sperm storage consists of multiple steps. Acp36DE enters the SSOs before sperm, and its residence within the SSOs does not require sperm. We propose that once sperm storage has initiated, Acp36DE acts as a guidance factor helping subsequent sperm move into storage, a corral concentrating sperm around the SSO entrances and/or a trigger for responses within the female that accelerate storage of sperm.
雌性精子储存是许多动物繁殖过程中的一个重要组成部分。在昆虫中，雌性精子储存会影响生育力、精子竞争/偏好以及再次交配的接受能力。雌性精子储存包括几个阶段，包括精子进入精子储存器官（SSO）、在SSO内的维持以及从SSO中排出。果蝇雄性生殖蛋白Acp36DE对雌性精子储存至关重要。Acp36DE与精子结合并定位于雌性生殖道的特定区域，包括SSO。我们通过比较在有或没有Acp36DE的情况下精子最初进入储存的时间以及精子从SSO中积累和释放的速率，来确定Acp36DE发挥作用的精子储存阶段。Acp36DE加速精子积累进入储存，但不介导第一个精子进入储存。这一发现还表明，精子储存的初始阶段包括多个步骤。Acp36DE在精子之前进入SSO，并且它在SSO内的停留不需要精子。我们提出，一旦精子储存开始，Acp36DE就作为一种引导因子，帮助后续精子进入储存，作为一个将精子聚集在SSO入口周围的畜栏，和/或作为雌性体内加速精子储存反应的触发因素。
