Dr. Ward demonstrated a long time ago that C. elegans sperm move by events at the surface rather than flagellar power. The major cytoskeletal protein, called msp, assembles into filament bundles which form the motile pseudopod. The PI here proposes to use genetic and molecular approaches to identify regulators of this process. Proposed are: (1) a two-hybrid assay to identify interacting domains of MSP, using mutants that may compensate for one another; (2) the same assay, to analyze candidate interacting proteins as well as screen for new ones; (3) in vitro assays for binding of interacting proteins to MSP dimers and filaments; (4) analysis of the spe6 mutations that either prevent MSP assembly or bypass hermaphrodite spermiogenesis block (this gene is a candidate for the connector between the spermiogenesis initiation signal and the assembly of MSP); (5) analysis of other spe genes that block hermaphrodite spermiogenesis.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
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Cellular Biology and Physiology Subcommittee 1 (CBY)
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Deatherage, James F
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University of Arizona
Schools of Arts and Sciences
United States
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Washington, Nicole L; Ward, Samuel (2006) FER-1 regulates Ca2+ -mediated membrane fusion during C. elegans spermatogenesis. J Cell Sci 119:2552-62
Cutter, Asher D; Ward, Samuel (2005) Sexual and temporal dynamics of molecular evolution in C. elegans development. Mol Biol Evol 22:178-88
Reinke, Valerie; Gil, Inigo San; Ward, Samuel et al. (2004) Genome-wide germline-enriched and sex-biased expression profiles in Caenorhabditis elegans. Development 131:311-23
Matyash, Vitali; Entchev, Eugeni V; Mende, Fanny et al. (2004) Sterol-derived hormone(s) controls entry into diapause in Caenorhabditis elegans by consecutive activation of DAF-12 and DAF-16. PLoS Biol 2:e280
Cutter, Asher D; Aviles, Leticia; Ward, Samuel (2003) The proximate determinants of sex ratio in C. elegans populations. Genet Res 81:91-102
Muhlrad, Paul J; Ward, Samuel (2002) Spermiogenesis initiation in Caenorhabditis elegans involves a casein kinase 1 encoded by the spe-6 gene. Genetics 161:143-55
LaMunyon, Craig W; Ward, Samuel (2002) Evolution of larger sperm in response to experimentally increased sperm competition in Caenorhabditis elegans. Proc Biol Sci 269:1125-8
Toyoda, H; Kinoshita-Toyoda, A; Selleck, S B (2000) Structural analysis of glycosaminoglycans in Drosophila and Caenorhabditis elegans and demonstration that tout-velu, a Drosophila gene related to EXT tumor suppressors, affects heparan sulfate in vivo. J Biol Chem 275:2269-75
Nance, J; Davis, E B; Ward, S (2000) spe-29 encodes a small predicted membrane protein required for the initiation of sperm activation in Caenorhabditis elegans. Genetics 156:1623-33
Toyoda, H; Kinoshita-Toyoda, A; Fox, B et al. (2000) Structural analysis of glycosaminoglycans in animals bearing mutations in sugarless, sulfateless, and tout-velu. Drosophila homologues of vertebrate genes encoding glycosaminoglycan biosynthetic enzymes. J Biol Chem 275:21856-61

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