6HW2 | pdb_00006hw2

The Crystal Structure of CaV beta4c in complex with HP1gamma chromo shadow domains

• PDB DOI: https://doi.org/10.2210/pdb6HW2/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Rattus norvegicus, Homo sapiens
• Expression System: Escherichia coli 'BL21-Gold(DE3)pLysS AG
• Mutation(s): No 


• Deposited: 2018-10-11 Released: 2020-01-29 
• Deposition Author(s): Tanner, N., Tripathy, D.R., Hirsch, J.A.
• Funding Organization(s): Israel Science Foundation

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.94 Å
• R-Value Free: 
  0.209 (Depositor), 0.208 (DCC) 
• R-Value Work: 
  0.177 (Depositor), 0.178 (DCC) 
• R-Value Observed: 
  0.179 (Depositor) 

Starting Model: experimental

Literature

The Crystal Structure of CaV beta4c in complex with HP1gamma chromo shadow domains

Tanner, N., Tripathy, D.R., Hirsch, J.A.

To be published.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A2B1 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - A2 

Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - A2 

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

Biological Assembly Evidence: assay for oligomerization

Macromolecule Content 

• Total Structure Weight: 35.17 kDa 
• Atom Count: 2,299 
• Modeled Residue Count: 259 
• Deposited Residue Count: 304 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Voltage-dependent L-type calcium channel subunit beta-4	A	154	Rattus norvegicus	Mutation(s): 0  Gene Names: Cacnb4
UniProt
Find proteins for D4A055 (Rattus norvegicus) Explore D4A055  Go to UniProtKB:  D4A055

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Chromobox protein homolog 3	B, C	75	Homo sapiens	Mutation(s): 0  Gene Names: CBX3
UniProt & NIH Common Fund Data Resources
Find proteins for Q13185 (Homo sapiens) Explore Q13185  Go to UniProtKB:  Q13185
PHAROS:  Q13185 GTEx:  ENSG00000122565

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	E [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
BME	G [auth A], H [auth A], I [auth A], K [auth C], N [auth C]	BETA-MERCAPTOETHANOL C2 H6 O S DGVVWUTYPXICAM-UHFFFAOYSA-N
ACT	L [auth C]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M
CA	D [auth A], F [auth A], J [auth B], M [auth C]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.94 Å
• R-Value Free:  0.209 (Depositor), 0.208 (DCC) 
• R-Value Work:  0.177 (Depositor), 0.178 (DCC) 
• R-Value Observed: 0.179 (Depositor) 

Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 115.026	α = 90
b = 58.036	β = 109.7
c = 57.546	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2020-01-29 
Deposition Author(s): Tanner, N., Tripathy, D.R., Hirsch, J.A.

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Funding Organization	Location	Grant Number
Israel Science Foundation	Israel	1201/04
Israel Science Foundation	Israel	1500/16

Revision History  

• Version 1.0: 2020-01-29
  Type: Initial release
  
• Version 1.1: 2024-01-24
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.2: 2025-10-01
  Changes: Advisory, Derived calculations, Structure summary