A saturable receptor for 32P-inositol-1,4,5-triphosphate in hepatocytes and neutrophils

Nature. 1986 Feb 6-12;319(6053):514-6. doi: 10.1038/319514a0.

Abstract

Several receptors for neurotransmitters, hormones and growth factors cause accelerated phosphodiesteratic breakdown of polyphosphoinositides when activated. One of the soluble products of this reaction, inositol-1,4,5-trisphosphate (Ins(1,4,5)P3) is thought to act as a second messenger signalling the release of Ca2+ from intracellular stores. In support of this hypothesis, several studies have shown that Ins(1,4,5)P3 releases sequestered Ca2+ from permeable cells and microsomes. On the basis of certain structural requirements for Ca2+-releasing activity by inositol phosphates, it has been postulated that Ins(1,4,5)P3 acts by binding to a specific intracellular receptor, probably on a component of the endoplasmic reticulum. Here we report that 32P-Ins(1,4,5)P3 binds to a specific saturable site in permeabilized guinea pig hepatocytes and rabbit neutrophils, and that the properties of this binding site suggest that it is the physiological receptor for Ins(1,4,5)P3.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Binding, Competitive
  • Calcium Channels*
  • Guinea Pigs
  • Inositol 1,4,5-Trisphosphate
  • Inositol 1,4,5-Trisphosphate Receptors
  • Inositol Phosphates / metabolism*
  • Kinetics
  • Liver / metabolism*
  • Neutrophils / metabolism*
  • Phosphorus Radioisotopes
  • Rabbits
  • Receptors, Cell Surface / metabolism*
  • Receptors, Cytoplasmic and Nuclear*
  • Sugar Phosphates / metabolism*

Substances

  • Calcium Channels
  • Inositol 1,4,5-Trisphosphate Receptors
  • Inositol Phosphates
  • Phosphorus Radioisotopes
  • Receptors, Cell Surface
  • Receptors, Cytoplasmic and Nuclear
  • Sugar Phosphates
  • Inositol 1,4,5-Trisphosphate