Connexin 32 G12R N-Terminal Mutant,

  • Classification: TRANSPORT PROTEIN
  • Organism(s): Homo sapiens
  • Mutation(s): Yes 

  • Deposited: 2016-06-21 Released: 2016-09-28 
  • Deposition Author(s): Dowd, T.L., Barigello, T.A.
  • Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 20 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


Structural studies of N-terminal mutants of Connexin 26 and Connexin 32 using (1)H NMR spectroscopy.

Batir, Y.Bargiello, T.A.Dowd, T.L.

(2016) Arch Biochem Biophys 608: 8-19

  • DOI: https://doi.org/10.1016/j.abb.2016.06.019
  • Primary Citation of Related Structures:  
    5KJ3, 5KJG, 5KK9

  • PubMed Abstract: 

    Alterations in gap junctions underlie the etiologies of syndromic deafness (KID) and Charcot-Marie Tooth disease (CMTX). Functional gap junctions are composed of connexin molecules with N-termini containing a flexible turn around G12, inserting the N-termini into the channel pore allowing voltage gating. The loss of this turn correlates with loss of Connexin 32 (Cx32) function by impaired trafficking to the cell membrane. Using (1)H NMR we show the N-terminus of a syndromic deafness mutation Cx26G12R, producing "leaky channels", contains a turn around G12 which is less structured and more flexible than wild-type. In contrast, the N-terminal structure of the same mutation in Cx32 chimera, Cx32*43E1G12R shows a larger constricted turn and no membrane current expression but forms membrane inserted hemichannels. Their function was rescued by formation of heteromeric channels with wild type subunits. We suggest the inflexible Cx32G12R N-terminus blocks ion conduction in homomeric channels and this channel block is relieved by incorporation of wild type subunits. In contrast, the increased open probability of Cx26G12R hemichannels is likely due to the addition of positive charge in the channel pore changing pore electrostatics and impairing hemichannel regulation by Ca(2+). These results provide mechanistic information on aberrant channel activity observed in disease.

  • Organizational Affiliation

    Department of Chemistry, Brooklyn College, Brooklyn, NY 11210, United States.


Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Gap junction beta-1 protein23Homo sapiensMutation(s): 1 
UniProt & NIH Common Fund Data Resources
Find proteins for P08034 (Homo sapiens)
Explore P08034 
Go to UniProtKB:  P08034
GTEx:  ENSG00000169562 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP08034
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Submitted: 20 

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM098584

Revision History  (Full details and data files)

  • Version 1.0: 2016-09-28
    Type: Initial release
  • Version 1.1: 2017-09-20
    Changes: Author supporting evidence, Database references, Structure summary
  • Version 1.2: 2019-12-25
    Changes: Author supporting evidence