Extracellular domain of YWK-II, a human sperm transmembrane protein, interacts with rat Mullerian-inhibiting substance

Abstract

The YWK-II protein in human spermatozoa is structurally related to the betaA4-amyloid precursor protein of Alzheimer disease and has high similarity with amyloid precusor homologues. Antibodies to the YWK-II protein agglutinate human spermatozoa and may be a potential cause of infertility. In the present study, a yeast two-hybrid system (MATCHMAKER Two-Hybrid System 2; Clontech, Palo Alto, CA) was used to screen a rat ovary cDNA library for potential ligands capable of interacting with the YWK-II component. Müllerian-inhibiting substance was found to interact with the extracellular domain of YWK-II protein. The interaction was confirmed by a binding experiment in vitro and surface plasmon resonance assays. The recombinant Müllerian-inhibiting substance can significantly increase the viability and longevity of human spermatozoa after 5 and 22 h of incubation, presumably through binding the YWK-II component on the sperm membrane. The results of this study indicate that the YWK-II sperm membrane protein may function as a receptor for Müllerian-inhibiting substance.

YWK-II protein as a novel Go-coupled receptor for Müllerian inhibiting substance in cell survival

“…Apart from the previously demonstrated binding of YWK-II protein to both rMIS and G o protein (Huang et al, 2000;Tian et al, 2001), the present study has provided further evidence of the involvement of YWK-II protein in MIS-activated and G ocoupled ERK signaling pathways as well as in mediating the effect of MIS on cell survival in a CHO model and mouse sperm in vitro and in vivo.…”

“…A eukaryotic expression vector containing mouse IgG signal peptide sequence, a cDNA segment of the YWK-II protein, the extracellular region previously used as a bait protein to detect interaction with rMIS in the yeast twohybrid system (Tian et al, 2001), and enhanced green fluorescence protein (EGFP) for detection purpose, was constructed (pEGFP-N1-YWK-II). When CHO cells were transiently transfected with the control vector pEGFP-N1 and the nuclei stained with propidium iodide (PI), EGFP was found, by confocal microscopy, to distribute evenly throughout the cells including the cytoplasm and nuclei (Fig.…”

“…When the extracellular segment of YWK-II protein was used as bait in a yeast two-hybrid system, a recombinant active MIS (303-376; rMIS) was found binding to YWK-II protein and the interaction was verified by a GST pull-down assay and by surface plasmon resonance (SPR) (Tian et al, 2001). On the other hand, rMIS has been shown to facilitate the motility and sustain the viability of human sperm (Tian et al, 2001); however, the mechanism of action of MIS on sperm remains unclear since an MIS type II receptor has not been shown to be present in germ cells (Teixeira and Donahoe, 1996;Baarends et al, 1994). We thus hypothesized that YWK-II protein may be a G o -coupled receptor involved in mediating the observed cell survival enhancing effect of MIS in sperm.…”

“…The G-proteincoupled activation of the ERK/MAPK phosphorylation cascades have been thought to play crucial roles in the regulation of cell cycle progression (or cell growth) and apoptosis (or cell survival) in diverse types of cells (Chang et al, 2003;Gudermann, 2001). The observed effects of MIS in promoting cell survival in sperm (Tian et al, 2001) and neurons (Wang et al, 2005), the demonstrated ability of YWK-II protein to interact with both MIS and G o protein, and the observed link between YWK-II protein/APLP2 and apoptosis and/or cell survival (Ariazi and Gould, 1996;Jarvis and Grant, 1999) suggest that YWK-II protein may serve as a G-proteincoupled receptor for MIS in cell survival.…”

Control of Spermatogenesis in Primate and Prospect of Male Contraception

“…Reproductive biologists in China have either identified or cloned such genes by using different animal models created for studying spermatogenesis [4,15,23,61,66] and spermatozoa maturation [28], although further functional studies are to be performed. Based on what is known about the molecular mechanisms of spermatogenesis and spermatozoa maturation in primates, an alternative approach to developing contraceptive is to use clinically available agents that have no obvious side effects and are effective to block particular steps during the process of spermatogenesis or sperm maturation [33].…”