The general objectives of this research plan are to determine how the sperm surface differentiates through spermatogenesis and how sperm surface components disperse in the egg surface after fertilization.
More specific aims i nclude: (1) the use of monoclonal antibodies against site-specific sperm surface antigens to determine when during spermatogenesis and where in the testis these antigens are added to the surfaces of spermatogenic cells; (2) to clone the genes coding for these site-specific surface antigens and, using these cloned genes, (3) to determine when during spermatogenesis and where in the testis these genes are transcribed; (4) to prepare and screen appropriate expression libraries from which these genes may be isolated, (5) to subclone these genes into appropriate transcription vectors, and (6) to devise effective sectioning techniques to carry out definitive in situ hybridization and antibody binding studies; (7) to determine whether site-specific sperm surface antigens disperse laterally on the surfaces of polyspermically fertilized eggs and, if so, (8) to determine the effects of cytoskeletal and metabolic inhibitors on this lateral dispersal; and, using recently developed procedures for fusing eggs, (9) to determine if sperm surface antigens disperse evenly in unfertilized- fertilized and fertilized-fertilized egg fusions. Since the surface antigens that will be studied possess Ca2+ -channeling capabilities and are known to be involved in the sperm acrosome reaction and sperm-egg binding, these aims and determinations should provide closer understandings of spermatogenesis, sperm fertility and infertility, sperm-egg binding, these aims and determinations should provide closer understandings of spermatogenesis, sperm fertility and infertility, sperm-egg binding, the transfer of sperm components to the fertilized egg, and the functions of sperm components in the early embryo. In more general biological terms, they should provide additional basic information about the movement of plasma membrane proteins in differentiating cells, the relationship between the cytoskeleton and membrane fluidity, membrane fusion, and cellular derepression.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD019054-05
Application #
3316225
Study Section
Reproductive Biology Study Section (REB)
Project Start
1984-12-01
Project End
1992-08-31
Budget Start
1990-09-01
Budget End
1991-08-31
Support Year
5
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Georgetown University
Department
Type
Schools of Arts and Sciences
DUNS #
049515844
City
Washington
State
DC
Country
United States
Zip Code
20057
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Vafa, O; Nishioka, D (1995) Developmentally regulated protease expression during sea urchin embryogenesis. Mol Reprod Dev 40:36-47
Ward, R D; Mendoza, L M; Moy, G W et al. (1994) A unique expression pattern for a sperm membrane protein during sea urchin spermatogenesis. Zygote 2:159-65
Ward, R D; Nishioka, D (1993) Seasonal changes in testicular structure and localization of a sperm surface glycoprotein during spermatogenesis in sea urchins. J Histochem Cytochem 41:423-31
Mendoza, L M; Nishioka, D; Vacquier, V D (1993) A GPI-anchored sea urchin sperm membrane protein containing EGF domains is related to human uromodulin. J Cell Biol 121:1291-7
Shen, R L; Ward, R D; Pinto da Silva, P et al. (1991) Localization of wheat germ agglutinin and antibody binding sites on the plasma membranes of sea urchin sperm heads as revealed by label-fracture and fracture-flip. Mol Reprod Dev 28:410-8
Nishioka, D; Ward, R D; Poccia, D et al. (1990) Localization of bindin expression during sea urchin spermatogenesis. Mol Reprod Dev 27:181-90
Cameron, R A; Minor, J E; Nishioka, D et al. (1990) Locale and level of bindin mRNA in maturing testis of the sea urchin, Strongylocentrotus purpuratus. Dev Biol 142:44-9
Nishioka, D; Gorman, E A; Ward, R D (1989) Changing localizations of site-specific sperm surface antigens during sea urchin fertilization. J Exp Zool 251:74-81
Semancik, G J; Shust, N M; Byrnes, S A et al. (1988) Induction of the cortical reaction in isolated sea urchin egg cortices: effects of Ca2+ and ionophore A23187. Cell Biol Int Rep 12:857-66

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