ITPR3

inositol 1,4,5-trisphosphate receptor type 3

Gene Function

Inositol 1,4,5-trisphosphate-gated calcium channel that, upon 1D-myo-inositol 1,4,5-trisphosphate binding, transports calcium from the endoplasmic reticulum lumen to cytoplasm, thus releasing the intracellular calcium and therefore participates in cellular calcium ion homeostasis. 1D-myo-inositol 1,4,5-trisphosphate binds to the ligand-free channel without altering its global conformation, yielding the low-energy resting state, then progresses through resting-to preactivated transitions to the higher energy preactivated state, which increases affinity for calcium, promoting binding of the low basal cytosolic calcium at the juxtamembrane domain (JD) site, favoring the transition through the ensemble of high-energy intermediate states along the trajectory to the fully-open activated state. Upon opening, releases calcium in the cytosol where it can bind to the low-affinity cytoplasmic domain (CD) site and stabilizes the inhibited state to terminate calcium release Source: UniProt

Relationship to CMT

CMT1 AD
1 subtype
6p21.31
First described 2020

Subtype Inheritance Class OMIM Sentinel Publication
SubtypeCMT1J Inheritanceautosomal dominant ClassCMT1 OMIM620111 Sentinel Publication

2020 · 10.1002/acn3.51190

Stored Identifiers

HGNC Aliases: IP3R3
hgnc_idHGNC:6182
ensembl_gene_idENSG00000096433
coords_grch38chr6:33620331-33696575
coords_grch37chr6:33588142-33664351
entrez_id3710
omim_gene147267
uniprot_idsQ14573
refseq_accessionNM_002224
mane_refseqNM_002224.4
mane_ensemblENST00000605930.3

ClinVar Variants

Pathogenic and likely pathogenic variants in ITPR3, as classified in ClinVar, are read live from NCBI. Only aggregate germline records are shown. Uncertain and conflicting classifications are not. Experts in CMT makes no claim to the accuracy of ClinVar data. This index is provided for informational purposes only.

Review stars are ClinVar’s measure of how well a classification is supported: four for a practice guideline, three for an expert panel review, two for agreement among multiple submitters, one for a single submitter with criteria provided, and none where no criteria were provided.

Reported in CMT
Reported in Other Diseases

Reported in a disease other than CMT. Listed apart rather than counted as CMT variants.

Variants w/o a Recorded Disease

Pathogenic or likely pathogenic in ClinVar, submitted without a disease recorded.

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