6BJF

NMR Structural and biophysical functional analysis of intracellular loop 5 of the NHE1 isoform of the Na+/H+ exchanger.


Experimental Data Snapshot

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

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Diverse residues of intracellular loop 5 of the Na+/H+exchanger modulate proton sensing, expression, activity and targeting.

Wong, K.Y.McKay, R.Liu, Y.Towle, K.Elloumi, Y.Li, X.Quan, S.Dutta, D.Sykes, B.D.Fliegel, L.

(2019) Biochim Biophys Acta Biomembr 1861: 191-200

  • DOI: 10.1016/j.bbamem.2018.07.014
  • Primary Citation of Related Structures:  
    6BJF

  • PubMed Abstract: 
  • The mammalian Na + /H + exchanger isoform 1 (NHE1) is an integral membrane protein that regulates intracellular pH (pH i ) by removing a single intracellular proton in exchange for one extracellular sodium ion. It is involved in cardiac hypertrophy and ischemia reperfusion damage to the heart and elevation of its activity is a trigger for breast cancer metastasis ...

    The mammalian Na + /H + exchanger isoform 1 (NHE1) is an integral membrane protein that regulates intracellular pH (pH i ) by removing a single intracellular proton in exchange for one extracellular sodium ion. It is involved in cardiac hypertrophy and ischemia reperfusion damage to the heart and elevation of its activity is a trigger for breast cancer metastasis. NHE1 has an extensive 500 amino acid N-terminal membrane domain that mediates transport and consists of 12 transmembrane segments connected by intracellular and extracellular loops. Intracellular loops are hypothesized to modulate the sensitivity to pH i . In this study, we characterized the structure and function of intracellular loop 5 (IL5), specifically amino acids 431-443. Mutation of eleven residues to alanine caused partial or nearly complete inhibition of transport; notably, mutation of residues L432, T433, I436, N437, R440 and K443 demonstrated these residues had critical roles in NHE1 function independent of effects on targeting or expression. The nuclear magnetic resonance (NMR) solution spectra of the IL5 peptide in a membrane mimetic sodium dodecyl sulfate solution revealed that IL5 has a stable three-dimensional structure with substantial alpha helical character. NMR chemical shifts indicated that K438 was in close proximity with W434. Overall, our results show that IL5 is a critical, intracellular loop with a propensity to form an alpha helix, and many residues of this intracellular loop are critical to proton sensing and ion transport.


    Organizational Affiliation

    Dept of Biochemistry, University of Alberta, Canada. Electronic address: lfliegel@ualberta.ca.



Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
GLY-LEU-THR-TRP-PHE-ILE-ASN-LYS-PHE-ARG-ILE-VAL-LYSA13Homo sapiensMutation(s): 0 
Gene Names: SLC9A1APNH1NHE1
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for P19634 (Homo sapiens)
Explore P19634 
Go to UniProtKB:  P19634
PHAROS:  P19634
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP19634
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

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

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-11-14
    Type: Initial release
  • Version 1.1: 2019-06-05
    Changes: Data collection, Database references