1SKT

SOLUTION STRUCTURE OF APO N-DOMAIN OF TROPONIN C, NMR, 40 STRUCTURES


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 40 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Low-temperature-induced structural changes in the Apo regulatory domain of skeletal muscle troponin C.

Tsuda, S.Miura, A.Gagne, S.M.Spyracopoulos, L.Sykes, B.D.

(1999) Biochemistry 38: 5693-5700

  • DOI: https://doi.org/10.1021/bi982936e
  • Primary Citation of Related Structures:  
    1SKT, 1ZAC

  • PubMed Abstract: 

    Contractile activity of skeletal muscle is triggered by a Ca2+-induced "opening" of the regulatory N-domain of troponin C (apo-NTnC residues 1-90). This structural transition has become a paradigm for large-scale conformational changes that affect the interaction between proteins. The regulatory domain is comprised of two basic structural elements: one contributed by the N-, A-, and D-helices (NAD unit) and the other by the B- and C-helices (BC unit). The Ca2+-induced opening is characterized by a movement of the BC unit away from the NAD unit with a concomitant change in conformation at two hinges (Glu41 and Val65) of the BC unit. To examine the effect of low temperatures on this Ca2+-induced structural change and the implications for contractile regulation, we have examined nuclear magnetic resonance (NMR) spectral changes of apo-NTnC upon decreasing the temperature from 30 to 4 degrees C. In addition, we have determined the solution structure of apo-NTnC at 4 degrees C using multinuclear multidimensional NMR spectroscopy. Decreasing temperatures induce a decrease in the rates and amplitudes of pico to nanosecond time scale backbone dynamics and an increase in alpha-helical content for the terminal helices of apo-NTnC. In addition, chemical shift changes for the Halpha resonances of Val65 and Asp66, the hinge residues of the BC, unit were observed. Compared to the solution structure of apo-NTnC determined at 30 degrees C, the BC unit packs more tightly against the NAD unit in the solution structure determined at 4 degrees C. Concomitant with the tighter packing of the BC and NAD structural units, a decrease in the total exposed hydrophobic surface area is observed. The results have broad implications relative to structure determination of proteins in the presence of large domain movements, and help to elucidate the relevance of structures determined under different conditions of physical state and temperature, reflecting forces ranging from crystal packing to solution dynamics.


  • Organizational Affiliation

    Bioscience and Chemistry Division, Hokkaido National Industrial Research Institute (HNIRI), Sapporo, Japan. tsuda@hniri.go.jp


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
TROPONIN-C90Gallus gallusMutation(s): 0 
Gene Names: NTNC
UniProt
Find proteins for P02588 (Gallus gallus)
Explore P02588 
Go to UniProtKB:  P02588
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP02588
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 40 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-12-09
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-03-02
    Changes: Data collection, Database references, Derived calculations, Experimental preparation, Other