Targeting the MEIG1/PACRG interaction for male contraception.

总结 男性避孕药的开发远远落后于女性避孕药。目前身体状况 男性节育的选择在可靠性、使用一致性和侵入性方面存在局限性， 分别。通过降低睾酮水平来抑制精子产生也会导致不可接受的后果 副作用。因此，我们的长期目标是开发一种能够阻止晚期妊娠的避孕药。 不使用激素的精子发生，因此效果可逆，副作用较少/无副作用 影响。 manchette 是一种短暂的含有微管的结构，仅存在于伸长过程中。 精子细胞和 manchette 结构/功能的遗传破坏导致男性不育。重要的是， 我们发现，砍刀在精子发生中的功能需要以下相互作用： 减数分裂表达基因 1 (MEIG1) 和 Parkin 共调控基因 (PACRG)。 MEIG1 的单点突变 或 PACRG 破坏两种蛋白质的相互作用也会破坏精子发生，导致纯男性 不孕症。 MEIG1 和 PACRG 之间的相互作用在人类中是保守的。我们假设化合物 破坏 MEIG1/PACRG 相互作用的药物可以开发成更安全有效的男性避孕药。 MEIG1/PACRG 结构的可用性使得计算机虚拟和人工智能 (AI) 成为可能 筛选阻断 MEIG1/PACRG 相互作用的小分子，并进行生化验证。因此， 本申请的目的是进行计算机虚拟和人工智能屏幕来识别小分子 阻断 MEIG1 和 PACRG 的相互作用，后者可开发为男性避孕药的先导化合物。对此 最后，我们为相互作用的稳健 G.princeps 荧光素酶互补测定提供了初步数据 MEIG1 和 PACRG 的结果可轻松用于验证从 虚拟和人工智能屏幕。此外，化合物片段库可用于物理筛选和 中断 MEIG1/PACRG 相互作用的片段也可用于未来的药物开发。因此， 我们提出以下两个目标： 1：完成计算机虚拟屏幕并检验小尺寸的效果 通过计算机虚拟和人工智能屏幕识别出中断 MEIG1/PACRG 相互作用的分子； 2：到 筛选片段库中破坏 MEIG1/PACRG 相互作用的化合物。我们期望确定 有可能中断 MEIG1/PACRG 相互作用并测试其效果的小分子/片段 使用已建立的测定法选择性小分子/片段。鉴于全球 Meig1 基因敲除小鼠和 单氨基酸突变 MEIG1 和 PACRG 小鼠均显示出仅雄性不育的表型， MEIG1/PACRG 相互作用被认为很少/没有副作用。拟议研究的最终目标 旨在将一种抑制精子形成/功能的男性避孕药推进到提交研究阶段 新药（IND）申请。男性“药丸”的发现和开发将造福广大民众 并减少意外怀孕。

Summary Development of male contraceptives has lagged far behind that of female contraceptives. Current physical options for male birth control have limitations with respect to reliability, consistency of use, and invasiveness, respectively. Inhibiting sperm production by decreasing testosterone levels would also cause unacceptable side effects. Thus, our long-term objective is to develop a contraceptive that blocks the late stage of spermatogenesis without the use of hormones so that the effect is reversible with fewer/no side effects. The manchette is a transient microtubule-containing structure that is present only in elongating spermatids, and genetic disruption of the manchette structure/function results in male infertility. Importantly, we have discovered that the function of the machete in spermatogenesis requires the interaction between meiosis expressed gene 1 (MEIG1) and Parkin co-regulated gene (PACRG). A single point mutation in MEIG1 or PACRG that disrupts the interaction of the two proteins also disrupts spermatogenesis resulting in pure male infertility. Interaction between MEIG1 and PACRG is conserved in humans. We hypothesize that compounds that disrupt the MEIG1/PACRG interaction can be developed into safer and effective male contraceptives. Availability of the MEIG1/PACRG structure makes it possible to in silico virtual and artificial intelligence (AI) screens for small molecules that block MEIG1/PACRG interaction, with biochemical validation hits. Thus, the objective of the present application is to conduct in silico virtual and AI screens to identify small molecules that block the interaction of MEIG1 and PACRG which can be developed into leads for male contraceptives. To this end, we provide preliminary data for a robust G. princeps luciferase complementation assay for the interaction of MEIG1 and PACRG that can be readily used to validate the effect of the small molecules identified from the virtual and AI screens. In addition, a fragment library for compounds is available for a physical screen and the fragments that interrupt MEIG1/PACRG interaction can also be used for drug development in the future. Thus, we propose the following two aims: 1: To complete the in silico virtual screen and to examine the effect of small molecules identified by the in silico virtual and AI screens on interrupting MEIG1/PACRG interaction; 2: To screen a fragment library for compounds that disrupt the MEIG1/PACRG interaction. We expect to identify small molecules/fragments that have the potential to interrupt MEIG1/PACRG interaction and test the effect of selective small molecules/fragments using the established assay. Given that global Meig1 knockout mice and both single amino acid mutant MEIG1 and PACRG mice showed a male infertility only phenotype, targeting MEIG1/PACRG interaction is believed to cause few/no side effects. The ultimate goal of the proposed studies is to advance a male contraceptive to inhibit sperm formation/function to the stage of filing an investigational new drug (IND) application. The discovery and development of a male “pill” will benefit the general population and reduce unintended pregnancies.