1IC2

DECIPHERING THE DESIGN OF THE TROPOMYOSIN MOLECULE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.249 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Deciphering the design of the tropomyosin molecule

Brown, J.H.Kim, K.-H.Jun, G.Greenfield, N.J.Dominguez, R.Volkmann, N.Hitchcock-DeGregori, S.E.Cohen, C.

(2001) Proc.Natl.Acad.Sci.USA 98: 8496-8501

  • DOI: 10.1073/pnas.131219198

  • PubMed Abstract: 
  • The crystal structure at 2.0-A resolution of an 81-residue N-terminal fragment of muscle alpha-tropomyosin reveals a parallel two-stranded alpha-helical coiled-coil structure with a remarkable core. The high alanine content of the molecule is cluster ...

    The crystal structure at 2.0-A resolution of an 81-residue N-terminal fragment of muscle alpha-tropomyosin reveals a parallel two-stranded alpha-helical coiled-coil structure with a remarkable core. The high alanine content of the molecule is clustered into short regions where the local 2-fold symmetry is broken by a small (approximately 1.2-A) axial staggering of the helices. The joining of these regions with neighboring segments, where the helices are in axial register, gives rise to specific bends in the molecular axis. We observe such bends to be widely distributed in two-stranded alpha-helical coiled-coil proteins. This asymmetric design in a dimer of identical (or highly similar) sequences allows the tropomyosin molecule to adopt multiple bent conformations. The seven alanine clusters in the core of the complete molecule (which spans seven monomers of the actin helix) promote the semiflexible winding of the tropomyosin filament necessary for its regulatory role in muscle contraction.


    Related Citations: 
    • Tropomyosin Crystal Structure and Muscle Regulation
      Phillips Jr., G.N.,Fillers, J.P.,Cohen, C.
      (1986) J.Mol.Biol. 192: 111
    • Crystal Structure of Tropomyosin at 7 Angstroms Resolution
      Whitby, F.G.,Phillips Jr., G.N.
      (2000) Proteins 38: 49
    • The Structure of the N-terminus of Striated Muscle alpha-Tropomyosin in a Chimeric Peptide: Nuclear Magnetic Resonance Structure and Circular Dichroism Studies
      Greenfield, N.J.,Montelione, G.T.,Farid, R.S.,Hitchcock-DeGregori, S.E.
      (1998) Biochemistry 37: 7834
    • Tropomyosin: Crystal Structure, Polymorphism and Molecular Interactions
      Caspar, D.L.,Cohen, C.,Longley, W.
      (1969) J.Mol.Biol. 41: 87


    Organizational Affiliation

    Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454-9110, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TROPOMYOSIN ALPHA CHAIN, SKELETAL MUSCLE
A, B, C, D
81Gallus gallusGene Names: TPM1
Find proteins for P04268 (Gallus gallus)
Go to Gene View: TPM1
Go to UniProtKB:  P04268
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.249 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 41.400α = 93.70
b = 45.500β = 98.10
c = 56.300γ = 104.40
Software Package:
Software NamePurpose
CNSrefinement
CCP4data scaling
MLPHAREphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-07-25
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance