2E30 | pdb_00002e30

Solution structure of the cytoplasmic region of Na+/H+ exchanger 1 complexed with essential cofactor calcineurin B homologous protein 1

• PDB DOI: https://doi.org/10.2210/pdb2E30/pdb

• Classification: METAL BINDING PROTEIN/TRANSPORT PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2006-11-19 Released: 2006-12-19 
• Deposition Author(s): Mishima, M., Wakabayashi, S., Kojima, C.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Solution structure of the cytoplasmic region of Na+/H+ exchanger 1 complexed with essential cofactor calcineurin B homologous protein 1

Mishima, M., Wakabayashi, S., Kojima, C.

(2007) J Biological Chem 282: 2741-2751

• PubMed: 17050540 
• DOI: https://doi.org/10.1074/jbc.M604092200
• Primary Citation Related Structures: 
  2E30


• PubMed Abstract: 
  

  Na+/H+ exchanger 1 (NHE1) regulates intracellular pH, Na+ content, and cell volume. Calcineurin B homologous protein 1 (CHP1) serves as an essential cofactor that facilitates NHE1 exchange activity under physiological conditions by direct binding to the cytoplasmic juxtamembrane region of NHE1. Here we describe the solution structure of the cytoplasmic juxtamembrane region of NHE1 complexed with CHP1. The region of NHE1 forms an amphipathic helix, which is induced by CHP1 binding, and CHP1 possesses a large hydrophobic cleft formed by EF-hand helices. The apolar side of the NHE1 helix participates in extensive hydrophobic interactions with the cleft of CHP1. We suggest that helix formation of the cytoplasmic region of NHE1 by CHP1 is a prerequisite for generating the active form of NHE1. The molecular recognition detailed in this study also provides novel insight into the target binding mechanism of EF-hand proteins.

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Organizational Affiliation: 
• Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 27.58 kDa 
• Atom Count: 1,935 
• Modeled Residue Count: 238 
• Deposited Residue Count: 238 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium-binding protein p22	A	195	Homo sapiens	Mutation(s): 0  Gene Names: CHP1
UniProt & NIH Common Fund Data Resources
Find proteins for Q99653 (Homo sapiens) Explore Q99653  Go to UniProtKB:  Q99653
PHAROS:  Q99653 GTEx:  ENSG00000187446

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Sodium/hydrogen exchanger 1	B	43	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P19634 (Homo sapiens) Explore P19634  Go to UniProtKB:  P19634
PHAROS:  P19634 GTEx:  ENSG00000090020

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	C [auth A], D [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2006-12-19 
Deposition Author(s): Mishima, M., Wakabayashi, S., Kojima, C.

Revision History  

• Version 1.0: 2006-12-19
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-03-09
  Changes: Data collection, Database references, Derived calculations
• Version 1.4: 2024-05-29
  Changes: Data collection