Abstract
Gap junction membrane channels assemble as dodecameric complexes, in which a hexameric hemichannel (connexon) in one plasma membrane docks end to end with a connexon in the membrane of a closely apposed cell. Steps in the synthesis, assembly and turnover of gap junction channels appear to follow the general secretory pathway for membrane proteins. In addition to homo-oligomeric connexons, different connexin polypeptide subunits can also assemble as hetero-oligomers. The ability to form homotypic and heterotypic channels that consist of two identical or two different connexons, respectively, adds even greater versatility to the functional modulation of gap junction channels. Electron cryocrystallography of recombinant gap junction channels has recently provided direct evidence for α-helical folding of at least two of the transmembrane domains within each connexin subunit. The potential to correlate the structure and biochemistry of gap junction channels with recently identified human diseases involving connexin mutations makes this a particularly exciting area of research.
Original language | English (US) |
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Pages (from-to) | 517-524 |
Number of pages | 8 |
Journal | Current Opinion in Structural Biology |
Volume | 8 |
Issue number | 4 |
DOIs | |
State | Published - Aug 1998 |
Funding
In accordance with the policies of Current Biology Publications, we regret that some papers published prior to 1996 could not be highlighted as being of special interest. This work was supported by grants from the National Institutes of Health (MMF and MY) and a Clinical Scientist Award in Translational Research from the Burroughs Wellcome Fund (MY). MMF and VMU are recipients of postdoctoral fellowships from the Deutsche Forschungsgemeinschaft and the American Heart Association, respectively. MY is an Established Investigator of the American Heart Association and Bristol-Myers Squibb.
ASJC Scopus subject areas
- Molecular Biology
- Structural Biology