Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Helical - H  (3D View)
Global Stoichiometry: Hetero 16-mer - A6B6C4 Pseudo Symmetry: Helical - H  (3D View)
Pseudo Stoichiometry: Hetero 16-mer - A6B6C2D2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 370.15 kDa 
• Atom Count: 24958 
• Modelled Residue Count: 3384 
• Deposited Residue Count: 3444 
• Unique protein chains: 3

6G2T

human cardiac myosin binding protein C C1 Ig-domain bound to native cardiac thin filament

• PDB DOI: 10.2210/pdb6G2T/pdb
• EM Map EMD-4346: EMDB EMDataResource

• Classification: CONTRACTILE PROTEIN
• Organism(s): Homo sapiens, Sus scrofa
• Expression System: Homo sapiens, Escherichia coli
• Mutation(s): No 


• Deposited: 2018-03-23 Released: 2018-10-17 
• Deposition Author(s): Risi, C., Belknap, B., Forgacs, E., Harris, S.P., Schroder, G.F., White, H.D., Galkin, V.E.
• Funding Organization(s): American Heart Association

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 9.00 Å
• Aggregation State: HELICAL ARRAY 
• Reconstruction Method: HELICAL 

Literature

N-Terminal Domains of Cardiac Myosin Binding Protein C Cooperatively Activate the Thin Filament.

Risi, C., Belknap, B., Forgacs-Lonart, E., Harris, S.P., Schroder, G.F., White, H.D., Galkin, V.E.

(2018) Structure 26: 1604-1611.e4

• PubMed: 30270174 
• DOI: 10.1016/j.str.2018.08.007
• Primary Citation of Related Structures:  
  6CXI, 6CXJ, 6G2T


• PubMed Abstract: 
  

Muscle contraction relies on interaction between myosin-based thick filaments and actin-based thin filaments. Myosin binding protein C (MyBP-C) is a key regulator of actomyosin interactions. Recent studies established that the N'-terminal domains (NTDs) of MyBP-C can either activate or inhibit thin filaments, but the mechanism of their collective action is poorly understood. Cardiac MyBP-C (cMyBP-C) harbors an extra NTD, which is absent in skeletal isoforms of MyBP-C, and its role in regulation of cardiac contraction is unknown. Here we show that the first two domains of human cMyPB-C (i.e., C0 and C1) cooperate to activate the thin filament. We demonstrate that C1 interacts with tropomyosin via a positively charged loop and that this interaction, stabilized by the C0 domain, is required for thin filament activation by cMyBP-C. Our data reveal a mechanism by which cMyBP-C can modulate cardiac contraction and demonstrate a function of the C0 domain.

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Organizational Affiliation: 

Department of Physiological Sciences, Eastern Virginia Medical School, 700 West Olney Road, Lewis Hall, Room 3126, Norfolk, VA 23507, USA. Electronic address: [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Actin, cytoplasmic 2	A, B, C, D, E, F	375	Homo sapiens	Mutation(s): 0  Gene Names: ACTG1, ACTG
UniProt & NIH Common Fund Data Resources
Find proteins for P63261 (Homo sapiens) Explore P63261  Go to UniProtKB:  P63261
PHAROS:  P63261

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Myosin-binding protein C, cardiac-type	G, H, I, J, K, L	109	Homo sapiens	Mutation(s): 0  Gene Names: MYBPC3
UniProt & NIH Common Fund Data Resources
Find proteins for Q14896 (Homo sapiens) Explore Q14896  Go to UniProtKB:  Q14896
PHAROS:  Q14896

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Tropomyosin	M, N, O, P	135	Sus scrofa	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 9.00 Å
• Aggregation State: HELICAL ARRAY 
• Reconstruction Method: HELICAL 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2018-03-23 
• Released Date: 2018-10-17 
Deposition Author(s): Risi, C., Belknap, B., Forgacs, E., Harris, S.P., Schroder, G.F., White, H.D., Galkin, V.E.

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Funding Organization	Location	Grant Number
American Heart Association	United States	16GRNT31220040

Revision History  

• Version 1.0: 2018-10-17
  Type: Initial release
  
• Version 1.1: 2018-12-19
  Changes: Data collection, Database references, Structure summary