Seminal CD38 Enhances Human Sperm Capacitation through Its Interaction with CD31

Abstract

Human sperm have to undergo a maturational process called capacitation in the female reproductive tract. Capacitation confers upon the sperm an ability to gain hypermotility and undergo acrosome reaction. Previous studies have suggested that seminal plasma proteins induce the capacitation of sperm in the female reproductive tract for the successful fertilization of the oocyte. However, the function of seminal plasma proteins in capacitation remains largely unclear. To the end, we found that soluble CD38 (sCD38) in seminal plasma increases the capacitation of sperm via specific interactions between sCD38 and the CD31 on the sperm. Upon the association of sCD38 with CD31, tyrosine kinase Src phosphorylates CD31, a process blocked by Src inhibitors. Shc, SHP-2, Grb2, and SOS, as well as Src kinase were found to associate with the phosphorylated CD31. The sCD38-induced phosphorylation of CD31 initiates a cascade reaction through the phosphorylation of Erk1/2, which results in the acrosome reaction, and sperm hypermotility. These processes were prevented by Src, Ras and MEK inhibitors. Taken together, these data indicate that the sCD38 present in seminal plasma plays a critical role in the capacitation of sperm.

FAK regulates actin polymerization during sperm capacitation via the ERK2/GEF-H1/RhoA signaling pathway

“…Previous research suggests that ERK1/2 have an important role in processes, such as capacitation, AR and motility. This suggestion is based on the use of MAPK pathway inhibitors that specifically inhibit MEK1/2, as MEK1/2 directly activate ERK1/2 (Almog et al, 2008;Awda and Buhr, 2010;Chiu et al, 2010;de Lamirande and Gagnon, 2002;du Plessis et al, 2001;Jaldety and Breitbart, 2015;Kim et al, 2015;Luconi et al, 1998a,b;Luna et al, 2012;Luo et al, 2015;Rahamim Ben-Navi et al, 2016). In our study here, we used the new inhibitor FR180204 that acts directly on the kinase activity of ERK1/2 (Ohori et al, 2005).…”

Proteomic Dissection of the Impact of Environmental Exposures on Mouse Seminal Vesicle Function

“…Indeed, elegant experiments to surgically excise the accessory glands have clearly established seminal vesicles as being the most influential tissue that contributes to the rodent ejaculate. In rodents, seminal vesicle secretions are directly implicated in regulating the conception environment within the female reproductive tract to elicit an immune response that promotes optimal fetal development and supports long-term offspring health ( 1 , 2 , 4 , 6 , 7 , 8 , 9 , 10 , 11 ). In view of the mounting evidence that such roles are conserved among mammals ( 12 , 13 , 14 ), it is likely that the complex molecular signals contained within seminal plasma are of critical importance for promoting reproductive success and maximizing progeny fitness.…”

Differentially expressed microRNA in testicular tissues of hyperuricaemia rats

“…CHRNA7 was a target mRNA for miR-144-3p, miR-99a-5p and miR-451-5p, and it has been shown that the motility of CHRNA7 -/spermatozoa is significantly impaired (Bray et al, 2005). For PDGFRB and CD38 (the target mRNAs of miR-509-5p and miR-451-5p), the former with genetic variation associates with semen production traits (S. Liu et al, 2017), while the latter induces phosphorylation of CD31, leading to acrosome reaction and high sperm motility (Kim et al, 2015). (Grisanti et al, 2009).…”