# BIOPHYSICAL CHEMICAL STUDIES OF MUSCLE PROTEINS

> **NIH NIH R01** · JOHNS HOPKINS UNIVERSITY · 1993 · $229,896

## Abstract

We plan to continue current physico-chemical studies on the
molecular mechanism of force-generation in vertebrate skeletal
muscle.  In these studies, we hope to test the helix-coil model
proposed for force-generation in muscle and compare the results
with those expected according to the classical rotating cross-
bridge mechanism.  An infrared, iodine photodissociation laser
will be used to heat fibers (approximately 5 degrees C) under 1
mu sec and the coupling between transient melting in (the S-2
region of) rigor cross-bridges and the development of tension will
be investigated in detail.  Experiments will be carried out under
ionic conditions where the S-2 elements of rigor bridges are
stabilized by association with the thick filament backbone and
where they are released from the backbone at various
temperatures and sarcomere lengths.  The kinetic constants and
amplitudes of the force transients will be compared to those of
activated fibers under a variety of environmental conditions in
these two states in an attempt to demonstrate the presence or
absence of common features  which could distinguish between
the two mechanisms.  We also plan to continue our investigations
of cross-linking of the rod segments within the thick filament
core of glycerinated rigor fibers in an attempt to decouple force
generation in the S-2 and S-1 regions of the cross-bridges.  The
effect of polyclonal antibodies specific to the S-2 region of
myosin on contractile force in glycerinated fibers is also under
study.  These experiments, like the cross-linking studies, are
designed to determine whether modulation of S-2 binding of a
cycling bridge to the thick filament surface has a direct effect
on force-generation.  The long range goal of these studies is to
understand the process of muscle contraction at a fundamental
level.  An understanding of this process has wide-ranging medical
implications.

## Key facts

- **NIH application ID:** 3154650
- **Project number:** 5R01AR004349-34
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **SAM.gov UEI:** FTMTDMBR29C7
- **Principal Investigator:** JULIEN S DAVIS
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1993
- **Award amount:** $229,896
- **Award type:** 5
- **Project period:** 1977-09-01 → 1995-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3154650

## Citation

> US National Institutes of Health, RePORTER application 3154650, BIOPHYSICAL CHEMICAL STUDIES OF MUSCLE PROTEINS (5R01AR004349-34). Retrieved via MORVS 2026-10-24 from https://api.morvs.ai/grant/nih/3154650. Licensed CC0.

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