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Mouse Sperm (mouse + sperm)
Selected AbstractsExclusive expression of a membrane-bound Spink3-interacting serine protease-like protein TESPL in mouse testisJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2010Chung-Mao Ou Abstract We identified a testis-specific protease-like protein tentatively named TESPL and a pancreatic trypsinogen Prss2 from the clones of a yeast two-hybrid screen against a mouse testicular cDNA library using the trypsin inhibitor Spink3 from male accessory sexual glands as bait. The enzymatic motifs and the cysteine patterns in serine proteases are highly conserved in these two proteins. Based on the phylogenetic analysis, Prss2 duplicated recently and TESPL underwent distant evolution without gene duplication from the progenitor of trypsin-like and chymotrypsin-like proteases. We found that TESPL transcription was restricted to the testis and that the level of transcription was positively correlated with animal maturation. In contrast, Prss2 was constitutively expressed in many tissues including testis. Alignment of the cDNA-deduced sequences of serine proteases showed the replacement of an essential serine residue in the catalytic triad of serine proteases by a proline residue in TESPL, which was demonstrated to be a membrane-bound protein devoid of proteolytic activity. The immunohistochemical staining patterns of seminiferous tubules in the testis revealed TESPL mainly on postmeiotic cells such as spermatids and spermatozoa. On the mouse sperm from caudal epididymis, TESPL was localized mainly on the plasma membrane overlaying the acrosomal region. Further, orthology group for mouse TESPL was identified in the conserved gene family of eutherian testis serine protease 5. J. Cell. Biochem. 110: 620,629, 2010. © 2010 Wiley-Liss, Inc. [source] Sperm surface arylsulfatase A can disperse the cumulus matrix of cumulus oocyte complexes,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2007Alexander Wu Cumulus cell layers of expanded cumulus oocyte complexes (COCs) are interlinked with networks of hyaluronic acid, chondroitin sulfate B proteoglycans and link proteins, and they can be dispersed by sperm surface hyaluronidases. In this report, we showed that arylsulfatase A (AS-A), existing on the sperm head surface, also had this dispersion action. Purified AS-A free of protease, hyaluronidase and chondroitinase activities could disperse the cumulus matrix of expanded COCs. However, this COC dispersion action was not associated with AS-A desulfation activity, assayed by using p -nitrocatecholsulfate (artificial substrate). COCs incubated for 1 h with sperm pretreated with anti-AS-A IgG in the presence of apigenin (a hyaluronidase inhibitor) did not exhibit matrix dispersion, whereas several cumulus layers were already dispersed in COCs incubated with sperm pretreated with preimmune IgG. Furthermore, sperm from AS-A null mice showed a significant delay in COC dispersion, compared with wild-type sperm. Within 1 h of sperm-COC co-incubation, the size of COCs incubated with AS-A null sperm was 65% of the original dimension, whereas that of COCs inseminated with wild-type sperm was only 17%. A further delay in COC dispersion by AS-A(,/,) mouse sperm was observed when apigenin was present in the co-incubation. We also showed for the first time that AS-A had a specific affinity for chondroitin sulfate B, a component of cumulus matrix proteoglycan networks; this might provide a mechanism of cumulus matrix destabilization induced by sperm surface AS-A. J. Cell. Physiol. 213: 201,211, 2007. © 2007 Wiley-Liss, Inc. [source] Bicarbonate-Induced phosphorylation of p270 protein in mouse sperm by cAMP-Dependent protein kinaseMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2008Masako Kaneto Abstract Signaling by cAMP-dependent protein kinase (PKA) plays an important role in the regulation of mammalian sperm motility. However, it has not been determined how PKA signaling leads to changes in motility, and specific proteins responsible for these changes have not yet been identified as PKA substrates. Anti-phospho-(Ser/Thr) PKA substrate antibodies detected a sperm protein with a relative molecular weight of 270,000 (p270), which was phosphorylated within 1 min after incubation in a medium supporting capacitation. Phosphorylation of p270 was induced by bicarbonate or a cAMP analog, but was blocked by the PKA inhibitor H-89, indicating that p270 is likely a PKA substrate in sperm. In addition, phosphorylation of p270 was inhibited by stearated peptide st-Ht31, suggesting that p270 is phosphorylated by PKA associated with an A-kinase anchoring protein (AKAP). AKAP4 is the major fibrous sheath protein of mammalian sperm and tethers regulatory subunits of PKA to localize phosphorylation events. Phosphorylation of p270 occurred in sperm lacking AKAP4, suggesting that AKAP4 is not involved directly in the phosphorylation event. Phosphorylated p270 was enriched in fractionated sperm tails and appeared to be present in multiple compartments including a detergent-resistant membrane fraction. PKA phosphorylation of p270 within 1 min of incubation under capacitation conditions suggests that this protein may have an important role in the initial signaling events that lead to the activation and subsequent hyperactivation of sperm motility. Mol. Reprod. Dev. 75: 1045,1053, 2007. © 2007 Wiley-Liss, Inc. [source] Cytoplasmic localization during testicular biogenesis of the murine mRNA for Spam1 (PH-20), a protein involved in acrosomal exocytosisMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2004Carlos R. Morales Abstract The Sperm Adhesion Molecule1 (SPAM1) is the most widely conserved sperm antigen with important roles in mammalian fertilization. Light and electron microscopy were used to localize, by in situ hybridization, the cellular and subcellular sites of Spam1 mRNA in the murine testis. Transcripts were first detected in step 3 round spermatids, gradually increased until step 8 and abruptly decreased between steps 9,11. They were predominantly localized near the ER and were not dispersed throughout the cytoplasm. Immunohistochemistry revealed that Spam1 is present on both the head and tail of sperm in the seminiferous tubules, and provided support for transcriptional regulation of its transcript. Immunocytochemistry confirmed the location of Spam1 on the tail of testicular sperm and demonstrated that it is localized to both the principal piece and the midpiece. Spam1 on epididymal sperm is localized to the midpiece of the tail and changes from a uniform distribution on the head in the caput to a regionalized pattern, first on the posterior and then on the anterior head, in caudal sperm. Spam1 on the surface of caudal sperm was shown to mediate the increase in acrosome reactions induced by the synergistic effects of HA and progesterone, as confirmed in sperm from the Rb(6.16) translocation-bearing mice which are Spam1 mutants. The similar response of human and mouse sperm to these agonists of the acrosome reaction, underscores the usefulness of the mouse as a model to study physiological aspects of SPAM1 in humans where, unlike the mouse, it is the only sperm hyaluronidase. Mol. Reprod. Dev. 69: 475,482, 2004. © 2004 Wiley-Liss, Inc. [source] Identification of Evolutionary Conserved Mouse Sperm Surface Antigens by Human Antisperm Antibodies (ASA) from Infertile PatientsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2006Agnieszka Paradowska Problem The presence of antisperm antibodies (ASA) in semen may impair sperm function leading to immunological infertility. The aim of the study was to identify the evolutionary conserved antigens on mouse sperm surface that react with human ASA in order to study the mechanism of autoimmune infertility. Methods of study The binding of human ASA to mouse sperm was investigated by means of indirect immunofluorescence. 2D-electrophoresis was applied to separate the biotin-labelled mouse membrane proteins using isoelectric focusing followed by polyacrylamide gel electrophoresis. Cognate antigens of ASA from seminal plasma of infertile patients were analysed by Western blotting. Performing avidin-blots it was detected which of the proteins recognized were sperm surface proteins. The spots of interest were analysed by means of mass spectrometry. Results ASA bound most frequently (36%) to the post-acrosomal region and to the midpiece of mouse spermatozoa. About 30% of ASA recognized apo lactate dehydrogenase (LDHC4) as a cognate antigen, 30% voltage-dependent anion channel (VDAC2). ASA of 20% bound to outer dense fibre protein and 20% of samples recognized glutathione S-transferase mu5. Conclusions Human ASA bound to specific cognate antigens of mouse spermatozoa, offering the possibility to study their functional relevance in the mouse model. [source] | ||||||||||