5MVY

Thin Filament at low calcium concentration


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 28.4 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Relaxed and active thin filament structures; a new structural basis for the regulatory mechanism.

Paul, D.M.Squire, J.M.Morris, E.P.

(2017) J Struct Biol 197: 365-371

  • DOI: https://doi.org/10.1016/j.jsb.2017.01.004
  • Primary Citation of Related Structures:  
    5MVA, 5MVY

  • PubMed Abstract: 

    The structures of muscle thin filaments reconstituted using skeletal actin and cardiac troponin and tropomyosin have been determined with and without bound Ca 2+ using electron microscopy and reference-free single particle analysis. The resulting density maps have been fitted with atomic models of actin, tropomyosin and troponin showing that: (i) the polarity of the troponin complex is consistent with our 2009 findings, with large shape changes in troponin between the two states; (ii) without Ca 2+ the tropomyosin pseudo-repeats all lie at almost equivalent positions in the 'blocked' position on actin (over subdomains 1 and 2); (iii) in the active state the tropomyosin pseudo-repeats are all displaced towards subdomains 3 and 4 of actin, but the extent of displacement varies within the regulatory unit depending upon the axial location of the pseudo-repeats with respect to troponin. Individual pseudo-repeats with Ca 2+ bound to troponin can be assigned either to the 'closed' state, a partly activated conformation, or the 'M-state', a fully activated conformation which has previously been thought to occur only when myosin heads bind. These results lead to a modified view of the steric blocking model of thin filament regulation in which cooperative activation is governed by troponin-mediated local interactions of the pseudo-repeats of tropomyosin with actin.


  • Organizational Affiliation

    Muscle Contraction Group, School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol BS8 1TD, UK. Electronic address: Danielle.paul@bristol.ac.uk.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Actin, alpha skeletal muscle
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W
375Oryctolagus cuniculusMutation(s): 0 
UniProt
Find proteins for P68135 (Oryctolagus cuniculus)
Explore P68135 
Go to UniProtKB:  P68135
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP68135
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
ADP
Query on ADP

Download Ideal Coordinates CCD File 
AA [auth D]
BA [auth E]
CA [auth F]
DA [auth G]
EA [auth H]
AA [auth D],
BA [auth E],
CA [auth F],
DA [auth G],
EA [auth H],
FA [auth I],
GA [auth J],
HA [auth K],
IA [auth L],
JA [auth M],
KA [auth N],
LA [auth O],
MA [auth P],
NA [auth Q],
OA [auth R],
PA [auth S],
QA [auth T],
RA [auth U],
SA [auth V],
TA [auth W],
X [auth A],
Y [auth B],
Z [auth C]
ADENOSINE-5'-DIPHOSPHATE
C10 H15 N5 O10 P2
XTWYTFMLZFPYCI-KQYNXXCUSA-N
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
HIC
Query on HIC
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W
L-PEPTIDE LINKINGC7 H11 N3 O2HIS
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 28.4 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-02-14
    Type: Initial release
  • Version 1.1: 2018-10-24
    Changes: Data collection, Database references