Opposing gates model for voltage gating of gap junction channels

Ye Chen-Izu, Alonso P. Moreno, Robert A. Spangler

Research output: Contribution to journalArticle

31 Scopus citations

Abstract

Gap junctions are intercellular channels that link the cytoplasm ot neighboring cells. Because a gap junction channel is composed of two connexons docking head-to-head with each other, the channel voltage-gating profile is symmetrical for homotypic channels made of two identical connexons (hemichannels) and asymmetric for the heterotypic channels made of two different connexons (i.e., different connexin composition). In this study we have developed a gating model that allows quantitative characterization of the voltage gating of homotypic and heterotypic channels. This model differs from the present model in use by integrating, rather than separating, the contributions of the voltage gates of the two member connexons. The gating profile can now be fitted over the entire voltage range, eliminating the previous need for data splicing and fusion of two hemichannel descriptions, which is problematic when dealing with heterotypic channels. This model also provides a practical formula to render quantitative several previously qualitative concepts, including a similarity principle for matching a voltage gate to its host connexon, assignment of gating polarity to a connexon, and the effect of docking interactions between two member connexons in an intact gap junction channel.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Cell Physiology
Volume281
Issue number5 50-5
StatePublished - 2001
Externally publishedYes

    Fingerprint

Keywords

  • Cell signaling
  • Connexin
  • Mathematical model

ASJC Scopus subject areas

  • Clinical Biochemistry
  • Cell Biology
  • Physiology
  • Physiology (medical)

Cite this