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V D Vacquier

Publications and source records attributed to V D Vacquier.

At least 109 records · Page 6Linked to original sources
PubMed1980

Sperm-specific surface antigenicity common to seven animal phyla.

While studying the plasma membrane of sperm of the sea urchin Strongylocentrotus purpuratus, we developed an antiserum that exhibits unusual reactivity--it cross-reacts with the surfaces of spermatozoa of 28 species representing seven phyla of the animal kingdom. A negative cross-reaction has not been found. This suggests the possible existence of common antigenic determinants on the surface of all animal sperm. We report these preliminary results here because of the broad implications common sperm-surface antigenicity has for the potential development of immunocontraceptive methods.

Animals↗
PubMed1978

Egg surface glycoprotein receptor for sea urchin sperm bindin.

Bindin is an insoluble protein coating the sperm acrosome process and mediating the adhesion of sperm to sea urchin eggs. Milligrams of bindin have been isolated. Here we report the identification, isolation, and partial characterization of a high molecular weight, trypsin-sensitive glycoprotein fraction from the sea urchin egg surface having species-specific affinity for bindin. This glycoprotein may be the egg surface receptor for bindin. The bindin receptor was released from 125-I-labeled eggs by parthenogenetic activation of eggs with ionophore A23187 in the presence of soybean trypsin inhibitor. The receptor has an isoelectric point of 4.02 and a molecular weight in sea water greater than or equal to 5 X 10(6), suggesting that it is an aggregate. It contains 34% neutral sugars, which are galactose and mannose.

Adhesiveness↗
PubMed1977

Isolation of bindin: the protein responsible for adhesion of sperm to sea urchin eggs.

The insoluble granular material of the acrosome vesicle of sea urchin sperm has been isolated and shown to be a single 30,500 dalton protein for which the name "bindin" is proposed. The data presented are consistent with the hypothesis that bindin is the adhesive responsible for the attachment of sperm to the vitelline layer of the egg. Experimental results suggest that bindin may act by binding to carbohydrate receptors of vitelline layer glycoproteins. The speculation is made that sperm bindins may be the general mechanism by which animal sperm attach to eggs.

Acrosome↗
PubMed1977

Cytasters from sea urchin eggs parthenogenetically activated by procaine.

A method is presented for the isolation of cytasters from unfertilized sea urchin eggs parthenogenetically activated by procaine. These cytasters do not appear to contain centrioles. The microtubules seem to grow out from the condensed chromosomes. The chromosomes have an unusual morphology.

Animals↗
PubMed1977

Isolation and characterization of the vitelline layer of sea urchin eggs.

The vitelline layers (VLs) of unfertilized sea urchin eggs were isolated by homogenization in a hypotonic medium containing Triton X-100 and EDTA. The surface topography of the VL is not changed by isolation. The thickness of the isolated VLs (300-400 A) is greater than that reported for VLs on intact eggs (100-200 A). Sperm adhere to the isolated VLs. When both internal and external VL surfaces are accessible to sperm, the sperm attach only to the external surface, suggesting that the external surface may carry sperm receptor proteins not present on the internal surface. Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis shows that isolated VLs are composed of numerous proteins ranging from greater than 213,000 to 25,000 daltons. Lactoperoxidase-catalyzed 125I-iodination of unfertilized eggs labels two high molecular weight bands that stain faintly for carbohydrate. VLs are 90% protein and 3.5% carbohydrate. No predominance of a single amino acid or class of amino acids was found. Carbohydrate analysis yields fucose, mannose, galactose, glucose, xylose, glucosamine, galactosamine, and sialic acid. Controls for purity indicate that isolated VLs contain 2% protein of cytoplasmic origin and no more than 2.5% egg jelly.

Animals↗
PubMed1976

Isolated cortical granules: a model system for studying membrane fusion and calcium-mediated exocytosis.

Cortical granules are secretory vesicles bound to the inner surface of the plasma membrane of sea urchin eggs. Intact granules can be isolated by shearing away the cytoplasm of eggs which have been bonded to a protamine-coated surface. When Ca2+ is added to preparations of isolated granules the granules fuse with each other and release their contents. It is believed that isolated cortical granules may be an excellent model system for the biochemical study of exocytosis.

Animals↗