# ITPR1

Source: https://onco.cc/targets/itpr1/  
OnCo record `itpr1` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

ITPR1 (Inositol 1,4,5-trisphosphate-gated calcium channel ITPR1) is a gene. In the public catalogues the evidence so far is association rather than a proven role.

## Summary

Inositol 1,4,5-trisphosphate-gated calcium channel that, upon inositol 1,4,5-trisphosphate binding, mediates calcium release from the endoplasmic reticulum (ER). Undergoes conformational changes upon ligand binding, suggesting structural flexibility that allows the channel to switch from a closed state, capable of interacting with its ligands such as 1,4,5-trisphosphate and calcium, to an open state, capable of transferring calcium ions across the ER membrane. Cytoplasmic calcium released from the ER triggers apoptosis by the activation of CAMK2 complex.

Open Targets scores its association with cancer at 0.52 (direct and indirect evidence; datatypes literature 0.94, animal model 0.58, genetic association 0.64).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: inositol 1,4,5-trisphosphate receptor type 1; Inositol 1,4,5-trisphosphate-gated calcium channel ITPR1; Insp3r1; IP3R1; PPP1R94; SCA15; SCA16; SCA29
- Tags: cancer-genes-wave
- Symbol: ITPR1
- Class: other
- Biology: Inositol 1,4,5-trisphosphate-gated calcium channel that, upon inositol 1,4,5-trisphosphate binding, mediates calcium release from the endoplasmic reticulum (ER). Undergoes conformational changes upon ligand binding, suggesting structural flexibility that allows the channel to switch from a closed state, capable of interacting with its ligands such as 1,4,5-trisphosphate and calcium, to an open state, capable of transferring calcium ions across the ER membrane. Cytoplasmic calcium released from the ER triggers apoptosis by the activation of CAMK2 complex. Involved in the regulation of epithelial secretion of electrolytes and fluid through the interaction with AHCYL1. Part of a complex composed of HSPA9, ITPR1 and VDAC1 that regulates mitochondrial calcium-dependent apoptosis by facilitating calcium transport from the ER lumen to the mitochondria intermembrane space thus providing calcium for the downstream calcium channel MCU that directly releases it into mitochondria matrix. Regulates fertilisation and egg activation by tuning the frequency and amplitude of calcium oscillations. Location: Endoplasmic reticulum membrane; Cytoplasmic vesicle, secretory vesicle membrane; Cytoplasm, perinuclear region (UniProt). Locus 3p26.1 (HGNC).

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: none stated by the sources. Evidence tier "association-only" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:6180: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6180
- UniProt Q14643: https://www.uniprot.org/uniprotkb/Q14643/entry
- NCBI Gene 3708: https://www.ncbi.nlm.nih.gov/gene/3708
- Ensembl ENSG00000150995: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000150995

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)

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JSON: https://onco.cc/api/v1/entities/itpr1.json