# NUCLEOPROTEINS IN MAMMALIAN SPERMATOGENESIS

> **NIH NIH R01** · UNIVERSITY OF TX MD ANDERSON CAN CTR · 1994 · $150,177

## Abstract

The displacement of histones from the spermatid nucleus is the first step
in a series of nucleoprotein transitions eventually leading to the
protamine-containing nucleus that appears to be essential for a normally
fertile mammalian sperm. The long-term objective is to elucidate the
mechanisms that are important for this displacement of histones. The goal
of this research is to describe the precise timing of the steps in the
nucleoprotein replacement process in rat spermatids. Techniques for
preparation of spermatid nuclei at well-defined steps (steps 2-4, 7-8, 9-
10, 11-12, 13-15) will be developed using rats in which the cycle of the
seminiferous epithelium is synchronized by manipulation of vitamin A
levels. Testes from these rats will be used as starting material for cell
separation by centrifugal elutriation and equilibrium density
centrifugation. The analyses will be designed to investigate several
hypotheses for mechanisms of histone displacement, by polyamines or more
basic proteins, and proteolysis. In the accurately staged populations of
nuclei, the levels of histone modification (acetylation, phosphorylation,
ubiquitination), the types of transition proteins (TP1, TP2 and others)
that are present after the loss of histones, the quantitative levels of
histones and transition proteins, the levels of polyamines, and the fate
of the displace histones will all be characterized. Polyacrylamide gel
electrophoresis will be used to perform most of the analyses of histones
although other techniques in protein chemistry will be applied as well.
These results will be analyzed to test which of the above hypotheses are
consistent with the actual time sequence of histone displacement in the
spermatids. The results will also be used to establish conditions for
preliminary in vitro studies on histone displacement from rat spermatid
nuclei at the appropriate step of development.

## Key facts

- **NIH application ID:** 2197373
- **Project number:** 5R01HD016843-11
- **Recipient organization:** UNIVERSITY OF TX MD ANDERSON CAN CTR
- **SAM.gov UEI:** S3GMKS8ELA16
- **Principal Investigator:** Marvin L. Meistrich
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1994
- **Award amount:** $150,177
- **Award type:** 5
- **Project period:** 1982-08-01 → 1994-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2197373

## Citation

> US National Institutes of Health, RePORTER application 2197373, NUCLEOPROTEINS IN MAMMALIAN SPERMATOGENESIS (5R01HD016843-11). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2197373. Licensed CC0.

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