Yayan Wang

Bio: Yayan Wang is an academic researcher from Peking Union Medical College. The author has contributed to research in topics: Capacitation & Sperm. The author has an hindex of 2, co-authored 3 publications receiving 11 citations.

Hsp90 modulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways.

Abstract: Heat shock protein 90 (Hsp90) is a highly abundant eukaryotic molecular chaperone that plays important roles in client protein maturation, protein folding and degradation, and signal transduction Previously, we found that both Hsp90 and its co-chaperone cell division cycle protein 37 (Cdc37) were expressed in human sperm Hsp90 is known to be involved in human sperm capacitation via unknown underlying mechanism(s) As Cdc37 was a kinase-specific co-chaperone of Hsp90, Hsp90 may regulate human sperm capacitation via other kinases It has been reported that two major mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase 1/2 (Erk1/2) and p38, are expressed in human sperm in the same locations as Hsp90 and Cdc37 Phosphorylated Erk1/2 has been shown to promote sperm hyperactivated motility and acrosome reaction, while phosphorylated p38 inhibits sperm motility Therefore, in this study we explored whether Hsp90 modulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways Human sperm was treated with the Hsp90-specific inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) during capacitation Computer-assisted sperm analyzer (CASA) was used to detect sperm motility and hyperactivation The sperm acrosome reaction was analyzed by using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (PSA-FITC) staining The interactions between Hsp90, Cdc37, Erk1/2 and p38 were assessed using co-immunoprecipitation (Co-IP) experiments Western blotting analysis was used to evaluate the levels of protein expression and phosphorylation Human sperm hyperactivation and acrosome reaction were inhibited by 17-AAG, suggesting that Hsp90 is involved in human sperm capacitation In addition, Co-IP experiments revealed that 17-AAG reduced the interaction between Hsp90 and Cdc37, leading to the dissociation of Erk1/2 from the Hsp90-Cdc37 protein complex Western blotting analysis revealed that levels of Erk1/2 and its phosphorylated form were subsequently decreased Decreasing of Hsp90-Cdc37 complex also affected the interaction between Hsp90 and p38 Nevertheless, p38 dissociated from the Hsp90 protein complex and was activated by autophosphorylation Taken together, our findings indicate that Hsp90 is involved in human sperm hyperactivation and acrosome reaction In particular, Hsp90 and its co-chaperone Cdc37 form a protein complex with Erk1/2 and p38 to regulate their kinase activity These results suggest that Hsp90 regulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways

Hsp90 interacts with Cdc37, is phosphorylated by PKA/PKC, and regulates Src phosphorylation in human sperm capacitation.

Abstract: Background Heat shock protein 90 (Hsp90) signaling pathways participate in protein phosphorylation during sperm capacitation. However, the underlying mechanism is largely unknown. Objective The aim of this study was to explore the interaction between Hsp90 and its co-chaperone protein, cell division cycle protein Cdc37 (Cdc37), in human spermatozoa. Materials and methods We examined the effects of H-89 (a protein kinase A [PKA] inhibitor) and Go6983 (a protein kinase C [PKC] inhibitor) on the phosphorylation of serine, threonine, and tyrosine residues in Hsp90; the effect of 17-allylamino-17-demethoxygeldanamycin (17-AAG, Hsp90 inhibitor) on Y416-Src phosphorylation; and the effects of 17-AAG and geldanamycin on threonine phosphorylation during human sperm capacitation. Results Hsp90 co-localized and interacted with Cdc37. During human sperm capacitation, Hsp90 phosphorylation at serine, threonine, and tyrosine residues was inhibited by H-89 and Go6983. In addition, phosphorylation of residue Y416 in the tyrosine kinase Src (its active site) was inhibited by 17-AAG, and the threonine phosphorylation levels of some proteins were decreased by 17-AAG and geldanamycin. Discussion and conclusion Taken together, our data showed that the interaction of Hsp90 with Cdc37 regulates total protein threonine phosphorylation and Src phosphorylation via its serine, threonine, and tyrosine phosphorylation, which are controlled by PKA and PKC during human sperm capacitation. The results of this study help understand the mechanism underlying Hsp90 regulation of sperm function.

MicroRNAs: Target Recognition and Regulatory Functions

Abstract: MicroRNAs (miRNAs) are endogenous ∼23 nt RNAs that play important gene-regulatory roles in animals and plants by pairing to the mRNAs of protein-coding genes to direct their posttranscriptional repression. This review outlines the current understanding of miRNA target recognition in animals and discusses the widespread impact of miRNAs on both the expression and evolution of protein-coding genes.

Quantitative Analysis of Hsp90-Client Interactions Reveals Principles of Substrate Recognition

Abstract: National Institutes of Health (U.S.). Genomics Based Drug Discovery-Driving Medical Project (Grant UL1-DE019585)

Hsp90 modulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways.

Abstract: Heat shock protein 90 (Hsp90) is a highly abundant eukaryotic molecular chaperone that plays important roles in client protein maturation, protein folding and degradation, and signal transduction Previously, we found that both Hsp90 and its co-chaperone cell division cycle protein 37 (Cdc37) were expressed in human sperm Hsp90 is known to be involved in human sperm capacitation via unknown underlying mechanism(s) As Cdc37 was a kinase-specific co-chaperone of Hsp90, Hsp90 may regulate human sperm capacitation via other kinases It has been reported that two major mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase 1/2 (Erk1/2) and p38, are expressed in human sperm in the same locations as Hsp90 and Cdc37 Phosphorylated Erk1/2 has been shown to promote sperm hyperactivated motility and acrosome reaction, while phosphorylated p38 inhibits sperm motility Therefore, in this study we explored whether Hsp90 modulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways Human sperm was treated with the Hsp90-specific inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) during capacitation Computer-assisted sperm analyzer (CASA) was used to detect sperm motility and hyperactivation The sperm acrosome reaction was analyzed by using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (PSA-FITC) staining The interactions between Hsp90, Cdc37, Erk1/2 and p38 were assessed using co-immunoprecipitation (Co-IP) experiments Western blotting analysis was used to evaluate the levels of protein expression and phosphorylation Human sperm hyperactivation and acrosome reaction were inhibited by 17-AAG, suggesting that Hsp90 is involved in human sperm capacitation In addition, Co-IP experiments revealed that 17-AAG reduced the interaction between Hsp90 and Cdc37, leading to the dissociation of Erk1/2 from the Hsp90-Cdc37 protein complex Western blotting analysis revealed that levels of Erk1/2 and its phosphorylated form were subsequently decreased Decreasing of Hsp90-Cdc37 complex also affected the interaction between Hsp90 and p38 Nevertheless, p38 dissociated from the Hsp90 protein complex and was activated by autophosphorylation Taken together, our findings indicate that Hsp90 is involved in human sperm hyperactivation and acrosome reaction In particular, Hsp90 and its co-chaperone Cdc37 form a protein complex with Erk1/2 and p38 to regulate their kinase activity These results suggest that Hsp90 regulates human sperm capacitation via the Erk1/2 and p38 MAPK signaling pathways

Effects of Cryopreservation on Gene Expression and Post Thaw Sperm Quality of Pacific Abalone, Haliotis discus hannai

Abstract: Pacific abalone, Haliotis discus hannai is a high commercial seafood in South-East Asia. The aim of the present study was to determine effects of cryopreservation on gene expression and post thaw sperm quality of Pacific abalone, H. discus hannai. Two ions, Na+ (459.1 ± 3.1 mM) and Cl- (515.9 ± 1.1 mM), were predominant in the seminal plasma (pH: 6.8 ± 0.1; osmolarity: 1126 ± 3 mOsmL-1). Cryopreservation reduced mRNA expression levels of protein kinase A (PKA-C) and heat shock proteins (HSP70 and HSP90) genes in sperm. Fluorescent technique was used to compare morphological defects, acrosome integrity (AI), plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), and DNA integrity of sperm cryopreserved with five different cryopreservation solutions (8% Me2SO, 8% EG, 6% PG, 2% GLY, and 2% MeOH). Droplet in tail and coiled tail defects were not observed for sperm cryopreserved with 8% Me2SO or 2% GLY. Sperm cryopreserved with 8% Me2SO showed improved DNA integrity and lower cryodamage than sperm cryopreserved with other cryoprotectants. Sperm to egg ratio of 10000:1 was found to be the most suitable ratio for in vitro fertilization among different ratios tested. The fertilization rate of sperm cryopreserved with 8% Me2SO was not significantly (p > 0.05) different from that of sperm cryopreserved with 2% GLY. DNA fragmentation showed strongly negative relationships with sperm quality parameters. Sperm cryopreserved with 8% Me2SO showed higher post thaw quality and mRNA expression of sperm motility associated gene than those cryopreserved with other cryoprotectants. The present research suggests to use 8% Me2SO for cryopreservation of Pacific abalone sperm as well as for hatchery production.

Redox Regulation to Modulate Phosphorylation Events in Human Spermatozoa

Abstract: Significance: Spermatozoa are complex and compartmentalized cells that undergo capacitation, a series of biochemical and morphological changes to acquire the ability to fertilize oocytes. Reactive oxygen species (ROS) have a prominent dual role in capacitation. At physiological levels, ROS regulate numerous cellular processes, including increases of cyclic adenosine monophosphate, calcium, and activation of phosphorylation events needed for capacitation. On the contrary, at high concentrations that do not impair sperm viability, ROS can cause loss of motility and inhibition of capacitation. Higher ROS concentrations promote oxidation of lipids, proteins, and DNA leading to cell death, and these damages have been associated with male infertility. Critical Issues: When incubated under specific conditions, spermatozoa can produce low and controlled amounts of ROS that are not harmful but instead regulate numerous cellular processes, including the phosphorylation of tyrosine, serine, and threonine residues in critical proteins needed for sperm capacitation. Here, we outline the complex redox signaling in human spermatozoa needed to achieve fertility and the role of ROS as physiological mediators that trigger phosphorylation cascades. Moreover, we illustrate the importance of various phosphoproteins in spermatozoa capacitation, viability, and hyperactive motility. Future Directions: Further studies to elucidate the different phosphorylation players during sperm capacitation and acrosome reaction (the regulated exocytotic event that releases proteolytic enzymes allowing the spermatozoon to penetrate the zona pellucida and fertilize the oocyte) are essential to understand how the spermatozoon acquires the fertilizing ability to fertilize the oocyte. This knowledge will serve to develop novel diagnostic tools and therapy for male infertility. Antioxid. Redox Signal. 37, 437–450.