Mammalian sperm are not able to fertilize eggs immediately after ejaculation. They acquire fertilization capacity after residing in the female tract for a finite period of time. The physiological changes occuring in the female reproductive tract that render the sperm able to fertilize constitute the phenomenon of """"""""sperm capacitation"""""""". It has been demonstrated that capacitation is associated with an increase in the tyrosine phosphorylation of a subset of proteins. It has also been demonstrated that the increase in protein tyrosine phosphorylation is regulated by a cAMP-dependent pathway involving protein kinase A (PKA). Hyperpolarization of the sperm plasma membrane has also been associated with capacitation. It is hypothesized that hyperpolarization of sperm plasma membrane during capacitation is, in some way, related to the cAMP-dependent phosphorylation of proteins. The objectives of this amended proposal are to elucidate the sequence of reactions and their mechanisms leading to hyperpolarization of mouse sperm during capacitation. The following specific aims are proposed: 1) to elucidate the role of media components in regulating sperm membrane potential and capacitation; 2) to determine the link between membrane hyperpolarization, cAMP and protein tyrosine phosphorylation; and 3) to define the regions of the sperm cell that display signal transduction during capacitation.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD038082-02
Application #
6388162
Study Section
Reproductive Biology Study Section (REB)
Program Officer
Rankin, Tracy L
Project Start
2000-07-01
Project End
2005-06-30
Budget Start
2001-07-01
Budget End
2002-06-30
Support Year
2
Fiscal Year
2001
Total Cost
$233,100
Indirect Cost
Name
University of Virginia
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
001910777
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Gervasi, María G; Xu, Xinran; Carbajal-Gonzalez, Blanca et al. (2018) The actin cytoskeleton of the mouse sperm flagellum is organized in a helical structure. J Cell Sci 131:
Tourzani, Darya A; Paudel, Bidur; Miranda, Patricia V et al. (2018) Changes in Protein O-GlcNAcylation During Mouse Epididymal Sperm Maturation. Front Cell Dev Biol 6:60
Stival, Cintia; Ritagliati, Carla; Xu, Xinran et al. (2018) Disruption of protein kinase A localization induces acrosomal exocytosis in capacitated mouse sperm. J Biol Chem 293:9435-9447
Romarowski, Ana; Velasco Félix, Ángel G; Torres Rodríguez, Paulina et al. (2018) Super-resolution imaging of live sperm reveals dynamic changes of the actin cytoskeleton during acrosomal exocytosis. J Cell Sci 131:
Orta, Gerardo; de la Vega-Beltran, José Luis; Martín-Hidalgo, David et al. (2018) CatSper channels are regulated by protein kinase A. J Biol Chem 293:16830-16841
Luque, Guillermina M; Dalotto-Moreno, Tomas; Martín-Hidalgo, David et al. (2018) Only a subpopulation of mouse sperm displays a rapid increase in intracellular calcium during capacitation. J Cell Physiol 233:9685-9700
Puga Molina, Lis C; Pinto, Nicolás A; Torres Rodríguez, Paulina et al. (2017) Essential Role of CFTR in PKA-Dependent Phosphorylation, Alkalinization, and Hyperpolarization During Human Sperm Capacitation. J Cell Physiol 232:1404-1414
Gervasi, M G; Visconti, P E (2017) Molecular changes and signaling events occurring in spermatozoa during epididymal maturation. Andrology 5:204-218
Stival, Cintia; Puga Molina, Lis del C; Paudel, Bidur et al. (2016) Sperm Capacitation and Acrosome Reaction in Mammalian Sperm. Adv Anat Embryol Cell Biol 220:93-106
Romarowski, Ana; Sánchez-Cárdenas, Claudia; Ramírez-Gómez, Héctor V et al. (2016) A Specific Transitory Increase in Intracellular Calcium Induced by Progesterone Promotes Acrosomal Exocytosis in Mouse Sperm. Biol Reprod 94:63

Showing the most recent 10 out of 92 publications