The long-term goal of this proposal is to characterize the organization of the telomere during spermatogenesis. A major emphasis is to define the molecules associated with the telomere chromosomal domains in human sperm. A component of the telomere-binding protein complex (hsTBP) - with binding affinity to the ds hexanucleotide repeat (TTAGGG) telomere DNA - has been identified and proposed to participate in the attachment of the telomeres to the nuclear envelope. One of the components of hsTBP, called spH2B, is regarded as a subtype of the somatic histone H2B. Another component of hsRBP is a novel 50 kDa protein identified as p50. Based on these data, the applicant proposes the isolation, cloning, and further characterization of spH2B and p50. This approach will enable the identification of additional components of hsTBP in human spermatogenic cells and sperm. Additional studies using atomic force microscopy and whole mount electron microscopy include a structural analysis of the telomeric DNA that appears to retain its nucleosomal-like organization. The latter studies will explore whether a variation of the recently reported t-loop characteristic of the telomere in somatic cells is observed using in situ cross-linked telomeric DNA preparations of sperm. The proposed studies are regarded as important for the regulation of telomerase activity during homologous chromosomal pairing and recombination during meiotic prophase and ordered chromosome withdrawal after fertilization.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
7R01HD039830-04
Application #
6790955
Study Section
Reproductive Biology Study Section (REB)
Program Officer
Taymans, Susan
Project Start
2003-09-01
Project End
2004-12-31
Budget Start
2003-09-01
Budget End
2004-12-31
Support Year
4
Fiscal Year
2003
Total Cost
$100,237
Indirect Cost
Name
Eastern Virginia Medical School
Department
Obstetrics & Gynecology
Type
Schools of Medicine
DUNS #
058625146
City
Norfolk
State
VA
Country
United States
Zip Code
23501
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