The protein encoded by this gene is an inositol 1,4,5-trisphosphate (InsP3) 5-phosphatase. InsP3 5-phosphatases hydrolyze Ins(1,4,5)P3, which mobilizes intracellular calcium and acts as a second messenger mediating cell responses to various stimulation. Studies of the mouse counterpart suggest that this protein may hydrolyze phosphatidylinositol 3,4,5-trisphosphate and phosphatidylinositol 3,5-bisphosphate on the cytoplasmic Golgi membrane and thereby regulate Golgi-vesicular trafficking. Mutations in this gene cause Joubert syndrome; a clinically and genetically heterogenous group of disorders characterized by midbrain-hindbrain malformation and various associated ciliopathies that include retinal dystrophy, nephronophthisis, liver fibrosis and polydactyly. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]
Forensic Context
A multi-omics study in humans identified the INPP5E as a key convergent gene in cocaine use disorder, showing hypomethylation at a specific CpG site, significant upregulation in expression, and differential alternative splicing in the prefrontal cortex [Zillich et al. DOI:10.1038/S41398-024-03139-9].