2MHF | pdb_00002mhf

Solution structure of the cyclic-nucleotide binding homology domain of a KCNH channel

• PDB DOI: https://doi.org/10.2210/pdb2MHF/pdb
• BMRB: 19621

• Classification: TRANSPORT PROTEIN
• Organism(s): Danio rerio
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2013-11-21 Released: 2014-04-02 
• Deposition Author(s): Li, Q., Ng, H.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 60 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Solution structure of the cyclic-nucleotide binding homology domain of a KCNH channel.

Li, Q., Ng, H.Q., Yoon, H.S., Kang, C.

(2014) J Struct Biol 186: 68-74

• PubMed: 24632450 
• DOI: https://doi.org/10.1016/j.jsb.2014.03.008
• Primary Citation Related Structures: 
  2MHF


• PubMed Abstract: 
  

  The carboxy-terminal region of the KCNH family of potassium channels contains a cyclic-nucleotide binding homology domain (CNBHD) that is important for channel gating and trafficking. The solution structure of the CNBHD of the KCNH potassium of zebrafish was determined using solution NMR spectroscopy. This domain exists as a monomer under solution conditions and adopts a similar fold to that determined by X-ray crystallography. The CNBHD does not bind cAMP because residue Y740 blocks the entry of cyclic-nucleotide to the binding pocket. Relaxation results show that the CNBHD is rigid except that some residues in the loop between β6 and β7 are flexible. Our results will be useful to understand the gating mechanism of KCNH family members through the CNBHD.

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Organizational Affiliation: 
• Institute of Chemical & Engineering Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore 627833, Singapore.
Experimental Therapeutics Centre, Agency for Science, Technology and Research (A∗STAR), Singapore 138669, Singapore.
Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637511, Singapore.
Experimental Therapeutics Centre, Agency for Science, Technology and Research (A∗STAR), Singapore 138669, Singapore. Electronic address: [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 16.18 kDa 
• Atom Count: 1,058 
• Modeled Residue Count: 135 
• Deposited Residue Count: 143 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Uncharacterized protein	A	143	Danio rerio	Mutation(s): 0  Gene Names: kcnh3
UniProt
Find proteins for A8WHX9 (Danio rerio) Explore A8WHX9  Go to UniProtKB:  A8WHX9

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 60 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2014-04-02 
Deposition Author(s): Li, Q., Ng, H.

Revision History  

• Version 1.0: 2014-04-02
  Type: Initial release
  
• Version 1.1: 2022-08-24
  Changes: Data collection, Database references
• Version 1.2: 2024-05-15
  Changes: Data collection, Database references