Biomaterial Database

Identification of a major polypeptide component of the sea urchin fertilization envelope. 1989

C A Vater, and R C Jackson

Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire 03756.

A monoclonal antibody (MAb No. 25-16), raised against purified cortical secretory vesicles (CVs) from the eggs of Strongylocentrotus purpuratus, has been used to identify a previously uncharacterized CV-derived polypeptide component of the sea urchin fertilization envelope (FE). MAb No. 25-16, an IgG1, bound to a group of proteins with Mr approximately 200,000 on immunoblots of CVs. This same group of proteins also was detected in fertilization product and in soft FEs prepared from early embryos, indicating that the antigen is released at fertilization by CV exocytosis and becomes incorporated into the FE. The multiple components recognized by MAb No. 25-16 apparently did not result from proteolysis during sample preparation or differential N-linked glycosylation. No simplification of the SDS-gel or immunoblot patterns was observed when samples of fertilization product or cell surface complex were prepared in the presence of a cocktail of protease inhibitors; nor was a change in mobility of any of the antigen forms detected following treatment with endoglycosidase F. Upon partial denaturation and reduction of the protein by incubation at room temperature in the presence of SDS and dithiothreitol, the antigen was shown to undergo a decrease in relative mobility on SDS-PAGE. Complete reduction and denaturation, by boiling in dithiothreitol-containing SDS sample buffer or by an on-blot reduction technique, resulted in loss of the epitope. The protein component recognized by MAb No. 25-16 underwent a striking increase in mobility on SDS-PAGE after chelation of calcium ions with EGTA. Immunogold labeling on thin sections of unfertilized eggs revealed that the antigen is located in the spiral lamellar cores of all CVs. In fertilized eggs, fixed 5 min after insemination, the antigen was detected in the FE. Based on these biochemical and immunological data, we suggest that the antigen recognized by MAb No. 25-16 is released exocytotically from the CVs into the perivitelline space at fertilization and becomes incorporated into the FE. The abundance of this antigen suggests that it may function as a structural component of the FE.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D011480	Protease Inhibitors	Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).	Antiprotease,Endopeptidase Inhibitor,Endopeptidase Inhibitors,Peptidase Inhibitor,Peptidase Inhibitors,Peptide Hydrolase Inhibitor,Peptide Hydrolase Inhibitors,Peptide Peptidohydrolase Inhibitor,Peptide Peptidohydrolase Inhibitors,Protease Antagonist,Protease Antagonists,Antiproteases,Protease Inhibitor,Antagonist, Protease,Antagonists, Protease,Hydrolase Inhibitor, Peptide,Hydrolase Inhibitors, Peptide,Inhibitor, Endopeptidase,Inhibitor, Peptidase,Inhibitor, Peptide Hydrolase,Inhibitor, Peptide Peptidohydrolase,Inhibitor, Protease,Inhibitors, Endopeptidase,Inhibitors, Peptidase,Inhibitors, Peptide Hydrolase,Inhibitors, Peptide Peptidohydrolase,Inhibitors, Protease,Peptidohydrolase Inhibitor, Peptide,Peptidohydrolase Inhibitors, Peptide
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D003594	Cytoplasmic Granules	Condensed areas of cellular material that may be bounded by a membrane.	Cytoplasmic Granule,Granule, Cytoplasmic,Granules, Cytoplasmic
D004527	Egg Proteins	Proteins which are found in eggs (OVA) from any species.	Egg Protein,Egg Shell Protein,Egg Shell Proteins,Egg White Protein,Egg White Proteins,Egg Yolk Protein,Egg Yolk Proteins,Ovum Protein,Ovum Proteins,Yolk Protein,Yolk Proteins,Protein, Egg,Protein, Egg Shell,Protein, Egg White,Protein, Egg Yolk,Protein, Ovum,Protein, Yolk,Proteins, Egg,Proteins, Egg Shell,Proteins, Egg White,Proteins, Egg Yolk,Proteins, Ovum,Proteins, Yolk,Shell Protein, Egg,Shell Proteins, Egg,White Protein, Egg,White Proteins, Egg,Yolk Protein, Egg,Yolk Proteins, Egg
D005306	Fertilization	The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.	Conception,Fertilization, Delayed,Fertilization, Polyspermic,Conceptions,Delayed Fertilization,Delayed Fertilizations,Fertilizations,Fertilizations, Delayed,Fertilizations, Polyspermic,Polyspermic Fertilization,Polyspermic Fertilizations
D005455	Fluorescent Antibody Technique	Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.	Antinuclear Antibody Test, Fluorescent,Coon's Technique,Fluorescent Antinuclear Antibody Test,Fluorescent Protein Tracing,Immunofluorescence Technique,Coon's Technic,Fluorescent Antibody Technic,Immunofluorescence,Immunofluorescence Technic,Antibody Technic, Fluorescent,Antibody Technics, Fluorescent,Antibody Technique, Fluorescent,Antibody Techniques, Fluorescent,Coon Technic,Coon Technique,Coons Technic,Coons Technique,Fluorescent Antibody Technics,Fluorescent Antibody Techniques,Fluorescent Protein Tracings,Immunofluorescence Technics,Immunofluorescence Techniques,Protein Tracing, Fluorescent,Protein Tracings, Fluorescent,Technic, Coon's,Technic, Fluorescent Antibody,Technic, Immunofluorescence,Technics, Fluorescent Antibody,Technics, Immunofluorescence,Technique, Coon's,Technique, Fluorescent Antibody,Technique, Immunofluorescence,Techniques, Fluorescent Antibody,Techniques, Immunofluorescence,Tracing, Fluorescent Protein,Tracings, Fluorescent Protein
D006026	Glycoside Hydrolases	Any member of the class of enzymes that catalyze the cleavage of the glycosidic linkage of glycosides and the addition of water to the resulting molecules.	Endoglycosidase,Exoglycosidase,Glycohydrolase,Glycosidase,Glycosidases,Glycoside Hydrolase,Endoglycosidases,Exoglycosidases,Glycohydrolases,Hydrolase, Glycoside,Hydrolases, Glycoside