Proteomic characterization of human sperm plasma membrane‐associated proteins and their role in capacitation

Abstract

BackgroundPlasma membranes of ejaculated sperm are covered by epididymal and accessory glands secreted proteins that must be released from sperm surface during the female reproductive tract passage in order to capacitate and fertilize the oocyte.ObjectivesAs human sperm plasma membrane‐associated proteins (SMAP) have not yet been investigated, the aim of this study was to characterize the SMAP released during in vitro human capacitation and to study their possible role as decapacitation factors.Materials and MethodsSMAP were characterized by 2‐dimensional electrophoresis and mass spectrometry analysis. Besides, we explored SMAP effects on motility, protein tyrosine phosphorylation, and calcium ionophore‐induced acrosome reaction of spermatozoa either incubated for 6 h in capacitating medium ± SMAP or for 5 h in capacitating medium alone followed by incubation for 1 h ± SMAP.ResultsMass spectrometry analysis allowed the identification of 29 proteins, all of which have previously been identified in the human seminal fluid. Spermatozoa incubated for 6 h under capacitating conditions in the presence of the SMAP showed a significant decrease in the incidence of non‐progressive motility, hyperactivation, protein tyrosine phosphorylation, and calcium ionophore‐induced acrosome reaction. However, spermatozoa incubated for 5 h in capacitating medium and further incubated for 1 h with the SMAP showed a lower percentage of spermatozoa with non‐progressive motility and hyperactivated cells but no effects on protein tyrosine phosphorylation were detected.Discussion and ConclusionsOur results indicate that SMAP inhibit the progress of human sperm capacitation, but only motility changes related to capacitation may be reversed by these proteins. The study of the identified proteins on sperm function and their mechanisms of action on this cell may contribute to the understanding of their role during capacitation.

Identification and Comparison of microRNAs in the Gonad of the Yellowfin Seabream (Acanthopagrus Latus)

“…To understand the relationships between DE miRNAs and the corresponding sex-related target genes, we constructed regulatory networks ( Figure 8 ). MiR-202-3p was predicted to target spaca4 , anxa1 , ccnb1 , sqle , and sperm flagellar protein 1; these genes are associated with gametogenesis, cellular signaling, and hormonal secretion [ 30 , 31 , 32 , 33 , 34 ]. The testis-biased miRNA let-7j was predicted to target cyp3c and lhb , two ovary-biased genes that may be associated with steroids synthesis and the sex hormone responsible for follicular development [ 35 ].…”

Proteomic Changes in Human Sperm During Sequential in vitro Capacitation and Acrosome Reaction

“…There are published reports that made use of MS to help identify protein differences before and after the induction of sperm capacitation in human and model species (Ficarro et al, 2003; Bailey et al, 2005; Sleight et al, 2005; Secciani et al, 2009; Baker et al, 2010; Zigo et al, 2013; Kwon et al, 2014; Wang J. et al, 2015; Hernández-Silva et al, 2019; Hou et al, 2019). However, the number of studies focusing on human sperm and using the most advanced techniques is limited.…”

“…The analysis of protein profiles of lysates obtained from human sperm cell has revealed a complex set of proteins involved in processes culminating in oocyte fertilization, including capacitation, the acrosome reaction, oocyte penetration and sperm-oocyte fusion (Castillo et al, 2018). Indeed, capacitation is the event most studied by the application of quantitative proteomic strategies in human (Ficarro et al, 2003; Secciani et al, 2009; Wang J. et al, 2015; Yu et al, 2015; Hernández-Silva et al, 2019) as well as in model species, such as mice (Baker et al, 2010), boars (Bailey et al, 2005; Kwon et al, 2014), bulls (Park et al, 2012) and buffalo (Jagan Mohanarao and Atreja, 2011; Hou et al, 2019). Recently, Hernández-Silva et al (2019) approached the proteomic study of human sperm capacitation from the alternative perspective of the seminal fluid components bathing sperm during and following ejaculation.…”

“…Indeed, capacitation is the event most studied by the application of quantitative proteomic strategies in human (Ficarro et al, 2003; Secciani et al, 2009; Wang J. et al, 2015; Yu et al, 2015; Hernández-Silva et al, 2019) as well as in model species, such as mice (Baker et al, 2010), boars (Bailey et al, 2005; Kwon et al, 2014), bulls (Park et al, 2012) and buffalo (Jagan Mohanarao and Atreja, 2011; Hou et al, 2019). Recently, Hernández-Silva et al (2019) approached the proteomic study of human sperm capacitation from the alternative perspective of the seminal fluid components bathing sperm during and following ejaculation. Interestingly, they found a group of seminal fluid derived proteins attached to the sperm surface which inhibits the progress of capacitation by negatively affecting sperm hyperactivation and protein tyrosine phosphorylation (Hernández-Silva et al, 2019).…”

“…Recently, Hernández-Silva et al (2019) approached the proteomic study of human sperm capacitation from the alternative perspective of the seminal fluid components bathing sperm during and following ejaculation. Interestingly, they found a group of seminal fluid derived proteins attached to the sperm surface which inhibits the progress of capacitation by negatively affecting sperm hyperactivation and protein tyrosine phosphorylation (Hernández-Silva et al, 2019).…”