The mechanism of the phosphorylation-dependent myosin-linked regulation of smooth muscle and nonmuscle myosins is being investigated. This involves several approaches: (1) measurement of rate constants for various steps in the kinetic cycle for the hydrolysis of MgATP by heavy meromyosin (HMM), the proteolytic subfragment of myosin, in the presence and absence of actin; (2) preparation of HMM from cytoplasmic myosins and characterization of their kinetic properties; and (3) use of an in vitro motility system to quantitate how the velocity of movement of myosin-coated beads is affected by various factors. We are also studying the mechanism of action of caldesmon, a possible regulatory protein associated with actin filaments.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Intramural Research (Z01)
Project #
1Z01HL001786-07
Application #
3966591
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
7
Fiscal Year
1986
Total Cost
Indirect Cost
Name
U.S. National Heart Lung and Blood Inst
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Young, Gavin; Hundt, Nikolas; Cole, Daniel et al. (2018) Quantitative mass imaging of single biological macromolecules. Science 360:423-427
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Kovacs, Mihaly; Wang, Fei; Hu, Aihua et al. (2003) Functional divergence of human cytoplasmic myosin II: kinetic characterization of the non-muscle IIA isoform. J Biol Chem 278:38132-40

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