Long-term Objectives: 1. To explore new types of motility within the myosin superfamily; 2. To address fundamental unresolved issues in motor protein biochemistry such as the relation of the powerstroke to the actin binding transitions and product release steps of myosin. Significance: Motility and contractility are essential for almost all biological processes. Detailed quantitative knowledge of the enzymology of molecular motors is a prerequisite for understanding biological motility and the basis of physiological processes connected to, among others, cardiac function and malfunction, asthma, axonal regeneration and sensory illnesses.
Specific Aims : 1. We will test the hypothesis that mechanical load has a functionally important effect on the product release kinetics of non-muscle myosin II; 2. We will assess if myosin X, a membrane-associated motor, has a unique mechanism of action that differs from all described types of myosin-based motility; 3. By mutational perturbation of the product release steps of myosin V, we will investigate the relation of product release to the mechanical step (powerstroke) and actin binding transitions of myosin. We will also establish the correspondence between the kinetic effects of the mutations and motility and processivity. Research Design and Methods: We will address the above questions by using single- and double-headed recombinant myosin constructs for solution kinetic, spectroscopic, biochemical and molecular mechanical investigations.

Agency
National Institute of Health (NIH)
Institute
Fogarty International Center (FIC)
Type
Research Project (R01)
Project #
5R01TW007241-04
Application #
7423910
Study Section
Special Emphasis Panel (ZRG1-BDA-E (50))
Program Officer
Liu, Xingzhu
Project Start
2005-09-30
Project End
2010-04-30
Budget Start
2008-05-01
Budget End
2009-04-30
Support Year
4
Fiscal Year
2008
Total Cost
$51,202
Indirect Cost
Name
Eotvos Lorand University
Department
Type
DUNS #
401221742
City
Budapest
State
Country
Hungary
Zip Code
H-105-3
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Toth, Judit; Varga, Balazs; Kovacs, Mihaly et al. (2007) Kinetic mechanism of human dUTPase, an essential nucleotide pyrophosphatase enzyme. J Biol Chem 282:33572-82
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