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Calvete JJ, Mann K, Schäfer W, Raida M, Sanz L, Töpfer-Petersen E. Boar spermadhesin PSP-II: location of posttranslational modifications, heterodimer formation with PSP-I glycoforms and effect of dimerization on the ligand-binding capabilities of the subunits. FEBS Lett 1995; 365:179-82. [PMID: 7781775 DOI: 10.1016/0014-5793(95)00452-f] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Spermadhesin PSP-II was isolated from the non-heparin-binding fraction of boar seminal plasma; its disulphide bridge pattern, and the location of a single N-glycosylation site were established. PSP-II forms a heterodimer with specific N-glycoforms of PSP-I. Although both subunits possess heparin-binding capability, the PSP-I/PSP-II complex does not. The heterodimer contains binding sites for zona pellucida glycoproteins and soybean trypsin inhibitor located in the PSP-II subunit. However, the PSP-I/PSP-II heterodimer binds only loosely to the sperm surface and is easily removed during in vitro capacitation, suggesting that the zona pellucida binding activity may not be relevant for gamete interaction. Our results show that dimerization of spermadhesins PSP-I and PSP-II markedly affects their binding capabilities.
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Affiliation(s)
- J J Calvete
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule, Hannover, Germany
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52
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Dostálová Z, Calvete JJ, Sanz L, Töpfer-Petersen E. Boar spermadhesin AWN-1. Oligosaccharide and zona pellucida binding characteristics. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 230:329-36. [PMID: 7601119 DOI: 10.1111/j.1432-1033.1995.tb20567.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have analyzed the oligosaccharide recognition ability of boar spermadhesin AWN-1 using biotinylated glycoproteins with defined carbohydrate chains as probes. Our results show that AWN-1 bound to proteins containing O-linked NeuAc alpha(2-3/6)-Gal beta(1-3)-GalNAc (PDC-109 and fetuin) with a Kd = 0.7 microM. AWN-1 also bound to NeuAc alpha(2-3/6)-Gal beta(1-4)-GlcNAc sequences in N-linked triantennary structures of fetuin, but not to the same oligosaccharide in the diantennary structures of IgG or fibrinogen. The absence of terminal sialic acid decreased fivefold the binding affinity. By competitive ELISA, peptides containing the N-linked oligosaccharide sequence inhibited the binding of the parent glycoprotein to immobilized AWN-1 5-45 times less effectively than those carrying O-linked NeuAc alpha(2-3/6)-Gal beta(1-3)-GalNAc structures. In addition, AWN-1 bound with a Kd = 0.3 microM to solubilized, biotinylated porcine zona pellucida glycoproteins. PDC-109 competed effectively with zona pellucida glycoproteins for AWN binding, whereas fetuin was a poor competitor. On the other hand, AWN epitopes were demonstrated on in vitro capacitated boar spermatozoa which were able to bind to, and penetrate, zona-encased oocytes. These data indicate that spermadhesin AWN-1 may play a role in pig fertilization as a sperm-associated lectin of broad specificity though preferential affinity for certain O-linked oligosaccharide structures of the oocyte's zona pellucida.
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Affiliation(s)
- Z Dostálová
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, Germany
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53
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Dostàlovà Z, Calvete JJ, Töpfer-Petersen E. Interaction of non-aggregated boar AWN-1 and AQN-3 with phospholipid matrices. A model for coating of spermadhesins to the sperm surface. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1995; 376:237-42. [PMID: 7626233 DOI: 10.1515/bchm3.1995.376.4.237] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Boar spermadhesins are 12-14 kDa lectins which coat the entire acrosomal cap sperm head surface. The large amount of spermadhesins AQN-1, AQN-2, AQN-3, and AWN-1 present on in vitro capacitated spermatozoa (approximately 7 x 10(6) molecules of each spermadhesin per cell) suggested that they may bind to major component(s) of the sperm surface. We have investigated both the aggregation state of spermadhesins in seminal plasma using gel filtration chromatography, and their ability to bind to the major phospholipids of the boar sperm plasma membrane, i.e. phosphorylcholine and phosphorylethanolamine. The bulk (90%) of spermadhesins AQN-3 and AWN-1 were eluted as aggregated proteins (Mr > 50,000) with the void volume of a Sephadex G-50 column; the remaining 10% of the total amount of seminal plasma AWN-1 and AQN-3 were recovered, together with the whole amount of AQN-1 and AQN-2, in a fraction containing low-molecular-mass proteins (Mr 16,000-30,000). None spermadhesin of either gel-filtration fraction bound to a phosphorylcholine affinity matrix. On the other hand, low-molecular-mass (monomeric or dimeric) AQN-3 and AWN-1 were the only spermadhesins retained in a phosphorylethanolamine affinity column. Both AQN-3 and AWN-1 purified from seminal plasma by reverse-phase HPLC retained their lipid-binding capability. In addition, immobilization of AQN-3 and AWN-1 onto a phosphorylethanolamine matrix did not interfere with the ability of the proteins to bind bovine glycoprotein PDC-109, indicating that the structural determinants for the binding lipid and carbohydrates lay on different structural domains.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- Z Dostàlovà
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule, Hannover-Kirchrode, Germany
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54
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Shimizu-Nishikawa K, Kajiwara K, Kimura M, Katsuki M, Sugaya E. Cloning and expression of SEZ-6, a brain-specific and seizure-related cDNA. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1995; 28:201-10. [PMID: 7723619 DOI: 10.1016/0169-328x(94)00203-q] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To clarify the molecular mechanism of neuronal bursting activity of seizures, we have constructed a cDNA library from mouse cerebrum cortex-derived cells treated with pentylentetrazole (PTZ), one of the convulsant drugs. Using a differential screening technique, several cDNA clones whose expressions change with PTZ-treatment were obtained. Among these clones, SEZ-6 was characterized by increased expression with PTZ. Detailed northern analysis showed that expression of SEZ-6 was limited to the brain and increased by the administration of PTZ not only in in vitro cultured cells but also in vivo. Analysis of SEZ-6 cDNA revealed multiple motifs, including typical signal sequence, threonine-rich domain, five copies of short consensus repeats (SCRs) or sushi domain (complement C3b/C4b binding site), two repeated sequences which were partially similar to the CUB domain or complement C1r/s-like repeat, one transmembrane domain and a short cytoplasmic segment in the C-terminal region. Although many proteins with multiple SCRs or CUB domains other than complement-related proteins have been found, this is the first report about a brain-specific cDNA which encodes membrane protein with both SCRs and CUB domain-like segments. Based on these findings, it is evident that SEZ-6 encodes a novel type of protein which may be related to seizure.
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55
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Calvete JJ, Nessau S, Mann K, Sanz L, Sieme H, Klug E, Töpfer-Petersen E. Isolation and Biochemical Characterization of Stallion Seminal-plasma Proteins. Reprod Domest Anim 1994. [DOI: 10.1111/j.1439-0531.1994.tb00588.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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56
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Dostàlovà Z, Calvete JJ, Sanz L, Hettel C, Riedel D, Schöneck C, Einspanier R, Töpfer-Petersen E. Immunolocalization and quantitation of acidic seminal fluid protein (aSFP) in ejaculated, swim-up, and capacitated bull spermatozoa. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1994; 375:457-61. [PMID: 7945995 DOI: 10.1515/bchm3.1994.375.7.457] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Acidic seminal fluid protein (aSFP, 12.9 kDa), a major protein of bull seminal plasma, belongs to the spermadhesin protein family. Boar spermadhesins become bound to the sperm head's surface at ejaculation and are thought to play a role as capacitation factors and/or in gamete recognition and binding. Here, we have investigated the topographical distribution and fate of bovine spermadhesin aSFP during sperm capacitation in order to assess whether aSFP could be involved in similar aspects of the fertilization process as its boar homologous proteins. 5.7 +/- 2.1 x 10(6) molecules/spermatozoa were quantitated on the surface of fresh ejaculated and washed sperm. The binding site of aSFP was restricted to a thin coat at the apical part of the acrosomal cap. The amount of aSFP in swim-up sperm was 1.8 +/- 1.0 x 10(6) molecules/spermatozoa, but decreased dramatically to 22 +/- 10 x 10(3) and to undetectable levels after incubation of sperm for 1.5 h and 18 h, respectively, in capacitation medium. This indicates that the bull spermatozoa surface may be completely depleted of spermadhesin aSFP before spermatozoa reach the surroundings of the investing egg. Therefore, our results suggest that aSFP may act as a decapacitation factor on bull spermatozoa rather than as a zona pellucida binding molecule.
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Affiliation(s)
- Z Dostàlovà
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, Germany
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57
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Dostàlovà Z, Calvete JJ, Sanz L, Töpfer-Petersen E. Quantitation of boar spermadhesins in accessory sex gland fluids and on the surface of epididymal, ejaculated and capacitated spermatozoa. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1200:48-54. [PMID: 8186232 DOI: 10.1016/0304-4165(94)90026-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Spermadhesins are multifunctional proteins involved in boar sperm capacitation and gamete recognition. Using anti-AWN antibodies, we have followed the fate of spermadhesin AWN along the maturation and capacitation stages of boar spermatozoa. In addition, the amount of spermadhesins AQN-1, AQN-2, and AQN-3 relative to that of AWN was determined by amino acid analysis after reverse-phase HPLC isolation. Our data show that AWN-1 is the only spermadhesin on the surface of epididymal sperm and that a large amount of AQN-1, AQN-2, AQN-3, AWN-1 and AWN-2 become coated on ejaculated spermatozoa. The number of spermadhesin molecules on ejaculated sperm (12-60 x 10(6)/spermatozoa) is sufficient to form a many-molecules-thick coat over the sperm head. However, 50-75% of the AQN-1, AQN-2, and AQN-3 population, and around 90% of coated AWN (1 + 2) are released from ejaculated sperm during capacitation. This indicates that a large subpopulation of each boar spermadhesin is loosely associated to the sperm surface and may function as decapacitation factors. The remaining spermadhesin molecules, which are tightly bound to the sperm head's surface may play a role as either positive capacitation factors and/or in gamete recognition and binding.
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Affiliation(s)
- Z Dostàlovà
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, FRG
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58
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Einspanier R, Krause I, Calvete JJ, Töfper-Petersen E, Klostermeyer H, Karg H. Bovine seminal plasma aSFP: localization of disulfide bridges and detection of three different isoelectric forms. FEBS Lett 1994; 344:61-4. [PMID: 8181566 DOI: 10.1016/0014-5793(94)00362-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Acidic seminal fluid protein (aSFP) is a major 13 kDa protein isolated from bull seminal plasma and characterized as a new growth factor which stimulates in vitro cell division and progesterone secretion by ovarian cells. Here, we establish that the four cysteines of oxidized aSFP form two disulfide bridges between nearest-neighbour residues. This pattern is conserved in boar spermadhesins, with which aSFP shares up to 50% amino acid sequence identity, and other proteins of the recently identified CUB domain family. Using isoelectric focusing in combination with sulfhydryl group-specific blotting, the three forms of aSFP were identified as completely oxidized (pI 4.7), partly reduced (pI 4.8) and fully reduced at pI 5.1. These results indicate that native aSFP possesses two pairs of cysteine residues of different reactivity. The observation that aSFP can protect sperm from oxidative damage might be explained by its reduction/oxidation behaviour.
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Affiliation(s)
- R Einspanier
- Institut für Physiologie, Forschungszentrum für Milch und Lebensmittel-Weihenstephan, Freising, Germany
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59
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Calvete JJ, Solís D, Sanz L, Díaz-Mauriño T, Schäfer W, Mann K, Töpfer-Petersen E. Characterization of two glycosylated boar spermadhesins. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 218:719-25. [PMID: 8269963 DOI: 10.1111/j.1432-1033.1993.tb18426.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Boar spermadhesins AQN-1, AQN-3 and AWN form a recently described protein family, synthesized by the sexual accessory glands, and become associated with the sperm head upon ejaculation. They contain 109-133 amino acid residues, two conserved disulphide bridges, are not glycosylated, and have 40-60% primary structure identity. These boar polypeptides are multifunctional proteins, which possess heparin-, serine-protease-inhibitor- and/or zona-pellucida-glycoprotein-binding capability and have, therefore, been implicated in sperm capacitation and sperm-oocyte attachment. AQN-2 (18-20 kDa), however, is unique among boar spermadhesins in that it is the only member of the family which is known to be glycosylated and which possesses weak zona-pellucida-binding but not seminal-plasma-inhibitor-binding ability. In this study we report the structural and functional characterization of the two glycoproteins contained in the AQN-2 fraction. One component is identical with PSP-I, a major porcine seminal plasma protein whose function has not yet been identified, while the second protein is a glycosylated isoform of AQN-3. Here we show that the inability of the glycosylated boar spermadhesins to bind seminal-plasma protease inhibitors as well as the weak binding of glycosylated AQN-3 to zona pellucida glycoproteins is due to the presence of the oligosacharide chain on a conserved asparagine residue. This indicates that modification of a spermadhesin polypeptide framework may serve to modulate its ligand-binding capabilities.
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Affiliation(s)
- J J Calvete
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, Germany
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60
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Calvete JJ, Sanz L, Dostàlovà Z, Töpfer-Petersen E. Characterization of AWN-1 glycosylated isoforms helps define the zona pellucida and serine proteinase inhibitor-binding region on boar spermadhesins. FEBS Lett 1993; 334:37-40. [PMID: 8224223 DOI: 10.1016/0014-5793(93)81675-p] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Spermadhesin AWN-1 (14 kDa) belongs to a recently described family of boar sperm surface-associated proteins. AWN-1 is a multifunctional protein which possesses heparin-, serine proteinase inhibitor-, and zona pellucida glycoprotein-binding capability. Therefore it has been implicated in sperm capacitation and sperm-oocyte attachment. Here, we report the characterization of 22-25 kDa isoforms of AWN-1 isolated by heparin-affinity chromatography, which fail to bind to zona pellucida glycoproteins or serine proteinase inhibitors. Our results show that the structure of the high and low molecular mass AWN-1 forms differ in that the former is N-glycosylated at Asp50 and truncated at the C-terminus. The inability of the glycosylated AWN-1 molecules to bind ligands is due solely to the presence of the oligosaccharide moieties, however. This indicates that glycosylation of AWN-1 may modulate its ligand-binding capabilities. On the other hand, the effect of glycosylation on ligand-binding suggests that both the zona pellucida- and the serine proteinase inhibitor binding domain(s) may be located around the glycosylation point.
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Affiliation(s)
- J J Calvete
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, Hannover-Kirchrode, Germany
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61
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Kwok SC, Yang D, Dai G, Soares MJ, Chen S, McMurtry JP. Molecular cloning and sequence analysis of two porcine seminal proteins, PSP-I and PSP-II: new members of the spermadhesin family. DNA Cell Biol 1993; 12:605-10. [PMID: 8397818 DOI: 10.1089/dna.1993.12.605] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Two full-length cDNAs encoding porcine seminal proteins, PSP-I and PSP-II, have been isolated from a porcine seminal vesicle cDNA library. Nucleotide sequence analysis of the 706-bp PSP-I cDNA predicts a precursor protein of 133 amino acid residues, which includes a 21-residue signal peptide and a 112-residue secreted protein. On the other hand, the complete sequence of the 686-bp PSP-II cDNA reveals a coding sequence for a 21-residue signal peptide and a 116-residue secreted protein. The predicted amino acid sequences agree very well with those determined by conventional amino acid sequence analysis. Alignment of the two cDNA sequences shows an overall 66% sequence homology throughout their entire length. However, the sequence homology is much higher in the 3' untranslated region (72%) than in the coding region (61%). This suggests that these two genes evolved by duplication and divergence from a common ancestral gene. They share about 50% amino acid sequence homology and a similar overall structure with three members of the spermadhesin family.
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Affiliation(s)
- S C Kwok
- Department of Obstetrics and Gynecology, Albert Einstein Medical Center, Philadelphia, PA 19141
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62
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Töpfer-Petersen E, Mann K, Calvete JJ. Identification of porcine oocyte 55 kDa alpha and beta proteins within the zona pellucida glycoprotein families indicates that oocyte sperm receptor activity is associated with different zone pellucida proteins in different mammalian species. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1993; 374:411-7. [PMID: 8216892 DOI: 10.1515/bchm3.1993.374.7-12.411] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Porcine zona pellucida (pZP) glycoprotein 55 kDa is composed of two core polypeptides, denominated alpha and beta. Sperm receptor activity has been shown to be associated with the oligosaccharide structures attached to the pZP55 alpha component. Here, we report a simple one-step HPLC procedure for the isolation of the alpha- and beta-components of the 55 kDa pZP proteins after enzymatic partial deglycosylation. N-Terminal sequence and protein chemical analysis of native proteins and of internal peptides from the alpha and the beta forms has established their homology with the rabbit 55 kDa zona pellucida glycoprotein and mouse ZP3, respectively. This, in turn, is relevant for a standardization of the ZP nomenclature in mammalian species. Moreover, our results imply that the sperm receptor activity in diverse mammalian species reside on oligosaccharide chains attached to nonhomologous zona pellucida glycoproteins. We hypothesize that acquisition of species-specific activity on the oocyte zona pellucida may thus be related to a species-specific glycosylation process.
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Affiliation(s)
- E Töpfer-Petersen
- Institut für Reproduktionsmedizin, Tierärztliche Hochschule Hannover, Germany
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63
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Kwok SC, Soares MJ, McMurtry JP, Yurewicz EC. Binding characteristics and immunolocalization of porcine seminal protein, PSP-I. Mol Reprod Dev 1993; 35:244-50. [PMID: 8352928 DOI: 10.1002/mrd.1080350305] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
PSP-I, a 13 kDa protein purified from boar seminal plasma, was found to have about 50% amino acid sequence homology with a family of zona pellucida-binding proteins known as spermadhesins. These proteins are produced by the accessory gland(s) of the male reproductive tract and coat the spermatozoa during ejaculation. In this study, we have investigated the possible biological functions of PSP-I using a solid-phase protein binding assay and its site of synthesis using both Western blot and immunocytochemical analyses. PSP-I was found to bind a number of proteins including endo-beta-galactosidase digested ZP3, soybean trypsin inhibitor, IgA, IgG and alpha-casein, indicating that it may have multiple functions. The protein or carbohydrate structures were not critical in the binding, since polyvinyl sulfate could effectively inhibit the binding of PSP-I to these proteins. Western blot analysis using specific antiserum to PSP-I showed that the protein was present in the seminal vesicle but not in the testes, epididymis or prostate. The protein was revealed by immunocytochemical analysis in the epithelium of seminal vesicles but not in the testes or the epididymis. It is concluded that PSP-I is synthesized by the epithelium of the seminal vesicles, secreted into the semen during ejaculation, and may be involved in various reproductive functions, such as preventing premature acrosome reaction and immunosuppression.
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Affiliation(s)
- S C Kwok
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City
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64
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Sanz L, Calvete JJ, Mann K, Gabius HJ, Töpfer-Petersen E. Isolation and biochemical characterization of heparin-binding proteins from boar seminal plasma: a dual role for spermadhesins in fertilization. Mol Reprod Dev 1993; 35:37-43. [PMID: 8507478 DOI: 10.1002/mrd.1080350107] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Sperm surface-coated heparin-binding proteins originating from secretions of the male sexual accessory glands, are known to play a pivotal role as extrinsic regulatory factors during sperm capacitation in many mammalian species. They interact with glycosaminoglycans present in the female genital tract and enhance the subsequent zona pellucida-induced acrosome reaction. We have isolated heparin-binding proteins from boar seminal plasma by affinity chromatography on heparin-Sepharose and reverse-phase HPLC. N-Terminal sequence analysis of these proteins identified a boar counterpart of the bovine capacitation factors BSP-A1/2 (also called PDC-109) and BSP-A3. Several carbohydrate- and zona pellucida-binding proteins, which belong to the newly described spermadhesin family, were also identified as heparin-binding proteins. Our results imply that, besides other capacitation factors, members of the spermadhesin family may play a dual role in sperm capacitation and fertilization in the pig.
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Affiliation(s)
- L Sanz
- Dermatologische Klinik und Poliklinik, UNiversität München, Federal Republic of Germany
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