Differentiation of spermatids into spermatozoa involves activation of transcription of unique genes and assembly of gamete-specific organelles including the acrosome and the flagellum. The objective of this proposal is to determine the role of the cAMP-dependent pathway during this differentiative process of the male gamete. We have made major progress in characterizing the enzymes involved in cAMP synthesis and degradation in round and elongating spermatids. Using the tools and models that we have developed, we now propose to study the mechanisms of regulation of these enzymes and the role of cAMP signaling in the spermatid-specific gene expression. The experiments described in this proposal are organized along two Specific Aims. With the first Specific Aim, we will address the role of adenylyl cyclases and phosphodiesterases in the control of cAMP levels in differentiating spermatids. The expression and subcellular localization of these enzymes as well as their retention in mature spermatozoa will be studied during spermatid development in vivo. The mechanisms of regulation of these enzymes will be investigated in a reconstitution system and in intact round and elongating spermatids. The second Specific Aim will be devoted to understanding how the cAMP signaling pathway is involved in the regulation of gene expression. In vitro studies will investigate how changes in cAMP concentration impact phosphorylation of cAMP-regulated transcription factors and expression of spermatid-specific genes. A genetic approach of transgenic overexpression or homologous recombination will be used to manipulate the cAMP- dependent pathway in vivo. Analysis of these in vivo models will elucidate how cAMP signaling controls gene expression and terminal differentiation of these germ cells. The proposed studies will further our understanding of regulation of spermatogenesis and sperm function. Moreover, they will help to identify novel targets for pharmacological manipulation of gamete production and fertility.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
2R01HD031544-06
Application #
6052340
Study Section
Special Emphasis Panel (ZRG1-BCE (01))
Program Officer
Tasca, Richard J
Project Start
1994-05-01
Project End
2005-02-28
Budget Start
2000-03-01
Budget End
2001-02-28
Support Year
6
Fiscal Year
2000
Total Cost
$225,560
Indirect Cost
Name
Stanford University
Department
Obstetrics & Gynecology
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
Gerona, Roy R; Schwartz, Jackie M; Pan, Janet et al. (2018) Suspect screening of maternal serum to identify new environmental chemical biomonitoring targets using liquid chromatography-quadrupole time-of-flight mass spectrometry. J Expo Sci Environ Epidemiol 28:101-108
Zota, Ami R; Linderholm, Linda; Park, June-Soo et al. (2013) Temporal comparison of PBDEs, OH-PBDEs, PCBs, and OH-PCBs in the serum of second trimester pregnant women recruited from San Francisco General Hospital, California. Environ Sci Technol 47:11776-84
Gerona, Roy R; Woodruff, Tracey J; Dickenson, Carrie A et al. (2013) Bisphenol-A (BPA), BPA glucuronide, and BPA sulfate in midgestation umbilical cord serum in a northern and central California population. Environ Sci Technol 47:12477-85
Xie, Fang; Eddy, Edward M; Conti, Marco (2013) Analysis of signaling pathways controlling flagellar movements in mammalian spermatozoa. Methods Enzymol 524:91-104
Moore, Simon W; Lai Wing Sun, Karen; Xie, Fang et al. (2008) Soluble adenylyl cyclase is not required for axon guidance to netrin-1. J Neurosci 28:3920-4
Schuh, Sonya M; Carlson, Anne E; McKnight, G Stanley et al. (2006) Signaling pathways for modulation of mouse sperm motility by adenosine and catecholamine agonists. Biol Reprod 74:492-500
Bajpai, Malini; Fiedler, Sarah E; Huang, Zaohua et al. (2006) AKAP3 selectively binds PDE4A isoforms in bovine spermatozoa. Biol Reprod 74:109-18
Xie, Fang; Garcia, Manuel A; Carlson, Anne E et al. (2006) Soluble adenylyl cyclase (sAC) is indispensable for sperm function and fertilization. Dev Biol 296:353-62
Livera, G; Xie, F; Garcia, M A et al. (2005) Inactivation of the mouse adenylyl cyclase 3 gene disrupts male fertility and spermatozoon function. Mol Endocrinol 19:1277-90
Esposito, Gloria; Jaiswal, Bijay S; Xie, Fang et al. (2004) Mice deficient for soluble adenylyl cyclase are infertile because of a severe sperm-motility defect. Proc Natl Acad Sci U S A 101:2993-8

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