Physical coupling between ryanodine receptor-calcium release channels

J Mol Biol. 2005 Jun 10;349(3):538-46. doi: 10.1016/j.jmb.2005.04.002. Epub 2005 Apr 25.

Abstract

Ryanodine receptor-calcium release channels play a pivotal role in the calcium signaling that mediates muscle excitation-contraction coupling. Their membrane organization into regular patterns, functional gating studies and theoretical analysis of receptor clustering have led to models that invoke allosteric interaction between individual channel oligomers as a critical mechanism for control of calcium release. Here we show that in reconstituted "checkerboard-like" lattices that mimic in situ membrane channel arrays, each oligomer is interlocked physically with four adjacent oligomers via a specific domain-domain interaction. Direct physical coupling between ryanodine receptors provides structural evidence for an inter-oligomer allosteric mechanism in channel regulation. Therefore, in addition to established cytosolic and luminal regulation of function, these observations indicate that channel-channel communication through physical coupling provides a novel mode of regulation of intracellular calcium release channels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium Signaling / physiology
  • Models, Molecular
  • Protein Structure, Tertiary
  • Rabbits
  • Ryanodine Receptor Calcium Release Channel / chemistry
  • Ryanodine Receptor Calcium Release Channel / metabolism*
  • Sarcoplasmic Reticulum / metabolism

Substances

  • Ryanodine Receptor Calcium Release Channel