Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein.

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Research Abstract Details 

Research Abstract Table of Contents

Jump to the:

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Abstract Text:

Alla S Kostyukova,Sarah E Hitchcock-Degregori,Norma J Greenfield,Alla S Kostyukova,Sarah E Hitchcock-Degregori,Norma J Greenfield,

The tropomodulin (Tmod) family of proteins that cap the pointed, slow-growing end of actin filaments require tropomyosin (TM) for optimal function. Earlier studies identified two regions in Tmod1 that bind the N terminus of TM, though the ability of different isoforms to bind the two sites is controversial. We used model peptides to determine the affinity and define the specificity of the highly conserved N termini of three short, non-muscle TMs (alpha, gamma, delta-TM) for the two Tmod1 binding sites using circular dichroism spectroscopy, native gel electrophoresis, and chemical crosslinking. All TM peptides have high affinity for the second Tmod1 binding site (within residues 109-144; alpha-TM, 2.5 nM; gamma-TM, delta-TM, 40-90 nM), but differ >100-fold for the first site (residues 1-38; alpha-TM, 90 nM; undetectable at 10 microM, gamma-TM, delta-TM). Residue 14 (R in alpha; Q in gamma and delta) and, to a lesser extent, residue 4 (S in alpha; T in gamma and delta) are primarily responsible for the differences. The functional consequence of the sequence differences is reflected in more effective inhibition of actin filament elongation by full-length alpha-TMs than gamma-TM in the presence of Tmod1. The binding sites of the two Tmod1 peptides on a model TM peptide differ, as defined by comparing (15)N,(1)H HSQC spectra of a (15)N-labeled model TM peptide in both the absence and presence of Tmod1 peptide. The NMR and CD studies show that there is an increase in alpha-helix upon Tmod1-TM complex formation, indicating that intrinsically disordered regions of the two proteins become ordered upon binding. A model proposed for the binding of Tmod to actin and TM at the pointed end of the filament shows how the Tmod-TM accentuates the asymmetry of the pointed end and suggests how subtle differences among TM isoforms may modulate actin filament dynamics.

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Publishing Authors By Initials

AS Kostyukova,SE Hitchcock-Degregori,NJ Greenfield,AS Kostyukova,SE Hitchcock-Degregori,NJ Greenfield,

For similar macromolecular substances: polymers: biopolymers: microfilament proteins: tropomyosin research abstracts see: macromolecular substances: polymers: biopolymers: microfilament proteins: tropomyosin research

PUBMED ID PMID:

MEDLINE DATE:

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Journal Published:

PUBLICATION TYPE: Research Support, Non-U.S. Gov

Journal: Journal of molecular biology

VOLUME: 372

Page Numbers: 608-18

Journal Abbreviation: J. Mol. Biol.

ISSN: 0022-2836

DAY: 2

MONTH: 06

YEAR: 2007

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Information

Number of References:

LANGUAGE: eng

NlmUniqueID: 2985088

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Keywords Mesh Terms:

KEYWORDS: Tropomyosin

MESH TERMS: metabolism

Chemical & Substance for Abstract: Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein. Information

Substance Name: Tropomyosin

Registry Number: 0

Grant and Affiliation Information for Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein.

AFFILIATION: Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA.

Country: England

AGENCY: United States NIGMS

GRANT: GM63257

ACRONYM: GM

MEDLINETA: J Mol Biol

REFSOURCE:

DATABASENAME:

ACCESSION NUMBER:

Number Hits: 0

Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein Related Publications

• 'DNA' may not mean 'did not participate': a qualitative study of reasons for non-adherence at home- and centre-based cardiac rehabilitation.
• A comparative multi-level analysis of contextual drinking in American and Canadian adults.
• A comparison of structural measurements using 2 Stratus optical coherence tomography instruments.
• A foetal plethysmograph.
• A method for measuring the blood flow in the umbilical vessels.
• A multifaceted approach to neuroscience outreach: meeting the challenges.
• Aging and surgeon performance.
• Book reviews.
• Comparison of the roles of IL-1, IL-6, and TNFalpha in cell culture and murine models of aseptic loosening.
• Concurrent validity of the Alcohol Use Disorders Identification Test (AUDIT) and AUDIT zones in defining levels of severity among out-patients with alcohol dependence in the COMBINE study.
• Determination of the folding of proteins as a function of denaturants, osmolytes or ligands using circular dichroism.
• Differential dynamics of transient neuronal assemblies in visual compared to auditory cortex.
• Evaluating quality improvement.
• Factor analysis of the Alcohol and Drug Confrontation Scale (ADCS).
• Highly stable plasminogen activator inhibitor type one (VLHL PAI-1) protects fibrin clots from tissue plasminogen activator-mediated fibrinolysis.
• Inhibition of the PI3K-Akt signaling pathway reduces tumor necrosis factor-alpha production in response to titanium particles in vitro.
• Making another world possible: the Torah, Louis Kelso, and the problem of poverty.
• Molecular basis of tropomyosin binding to tropomodulin, an actin-capping protein.
• Next generation of self-management education: Web-based bipolar disorder program.
• Olivoponto-cerebellar atrophy.
• Part XIII. Systemic antifungal therapy.
• Part XIV. Antiviral agents other than antiretrovirals: therapy for herpesvirus infections, viral hepatitis, and influenza.
• Recent advances in analytical spectroscopy by K. Fuwa. Pergamon Press, Oxford, 1982, pp. 325, ISBN 0-08-026221 1X, pound42.00.
• Reflections on leukemia and adult stem-cell transplantation: some personal psychological factors.
• Relaxation time, diffusion, and viscosity analysis of model asphalt systems using molecular simulation.
• Scanning laser polarimetry with enhanced corneal compensation and optical coherence tomography in normal and glaucomatous eyes.
• Sexually dimorphic expression of secreted frizzled-related (SFRP) genes in the developing mouse Müllerian duct.
• The balance between endotoxin accumulation and clearance during particle-induced osteolysis in murine calvaria.
• The relationship of self-esteem and self-efficacy to treatment outcomes of alcohol-dependent men and women.
• Using circular dichroism collected as a function of temperature to determine the thermodynamics of protein unfolding and binding interactions.