Structure and function of inositol 1,4,5-trisphosphate receptors

Srikanth, Sonal ; Hasan, Gaiti (2004) Structure and function of inositol 1,4,5-trisphosphate receptors Current Science, 86 (11). pp. 1513-1523. ISSN 0011-3891

PDF - Publisher Version

Official URL:


The InsP3R is an intracellular calcium release channel that forms an important component of the InsP3 signalling pathway and is ubiquitously expressed in multicellular organisms. Molecular studies have identified three separate genes in mammals that code for the three isoforms of InsP3Rs. These three isoforms are shown to have different ligand affinities and modulatory properties. These differences are presently thought to generate the heterogeneity required in calcium dynamics to regulate processes as diverse as secretion, synaptic plasticity, immune responses in T cells and fertilization events in sea urchin eggs. The understanding of these processes mandates an understanding of the single channel properties of the three isoforms as well as splice variants that are expressed in a tissue-specific manner. Recent single channel studies aimed at understanding the functional properties of the InsP3Rs using point mutants in the channel have uncovered important residues that affect the calcium dependence and ion selectivity of the channel. Genetic studies using knockouts of the mammalian InsP3Rs appear inadequate to relate the channel function to the physiological behaviour at an animal level most likely due to compensation by other isoforms of the channel. In this scenario, study of InsP3R in Drosophila melanogaster, that encodes a single gene for InsP3R should prove useful in correlating single channel properties of the channel with phenotypes of the whole organism.

Item Type:Article
Source:Copyright of this article belongs to Current Science Association.
ID Code:14978
Deposited On:13 Nov 2010 13:11
Last Modified:16 May 2016 23:57

Repository Staff Only: item control page