ITPKB

Inositol-trisphosphate 3-kinase B is an enzyme that in humans is encoded by the ITPKB gene.^[5][6]

ITPKB
Identifiers
Aliases	ITPKB, IP3-3KB, IP3K, IP3K-B, IP3KB, PIG37, inositol-trisphosphate 3-kinase B
External IDs	OMIM: 147522; MGI: 109235; HomoloGene: 1672; GeneCards: ITPKB; OMA:ITPKB - orthologs
Gene location (Human) Chr. Chromosome 1 (human)[1] Band 1q42.12 Start 226,631,690 bp[1] End 226,739,323 bp[1]
Gene location (Mouse) Chr. Chromosome 1 (mouse)[2] Band 1 H4|1 84.27 cM Start 180,158,050 bp[2] End 180,252,367 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in external globus pallidus pars reticulata dorsal motor nucleus of vagus nerve internal globus pallidus inferior olivary nucleus pars compacta subthalamic nucleus ventral tegmental area superior vestibular nucleus middle frontal gyrus Top expressed in choroid plexus of fourth ventricle lactiferous gland sciatic nerve islet of Langerhans right lung internal carotid artery blood thymus left lung right lung lobe More reference expression data BioGPS More reference expression data
Gene ontology Molecular function transferase activity nucleotide binding calmodulin binding kinase activity protein binding ATP binding inositol-1,4,5-trisphosphate 3-kinase activity Cellular component cytosol membrane nucleus Biological process regulation of protein phosphorylation cellular response to calcium ion negative regulation of neutrophil apoptotic process phosphorylation common myeloid progenitor cell proliferation myeloid cell homeostasis positive regulation of Ras protein signal transduction inositol phosphate metabolic process inositol trisphosphate metabolic process MAPK cascade cell surface receptor signaling pathway T cell differentiation positive thymic T cell selection negative regulation of myeloid cell differentiation positive regulation of alpha-beta T cell differentiation thymic T cell selection signal transduction inositol phosphate biosynthetic process Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3707 320404 Ensembl ENSG00000143772 ENSMUSG00000038855 UniProt P27987 B2RXC2 RefSeq (mRNA) NM_002221 NM_001388404 NM_001081175 RefSeq (protein) NP_002212 NP_001074644 Location (UCSC) Chr 1: 226.63 – 226.74 Mb Chr 1: 180.16 – 180.25 Mb PubMed search [3] [4]
Wikidata
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Function

The protein encoded by the ITPKB gene is one of 3 isoforms of Inositol-trisphosphate 3-kinase expressed in humans. ITPKB protein regulates inositol phosphate metabolism by phosphorylation of second messenger inositol 1,4,5-trisphosphate, which releases calcium from intracellular store in the endoplasmic reticulum by gating the inositol trisphosphate receptor. ITPKB produces Ins(1,3,4,5)P4, which does not gate the inositol trisphosphate receptor. The enzyme specifically phosphorylates the 1,4,5 isomer of IP3. The activity of this encoded protein is responsible for regulating the levels of a large number of inositol polyphosphates that are important in cellular signaling. Both calcium/calmodulin and protein phosphorylation mechanisms control its activity.^[7] Itpkb regulates immune cell function and is required for T and B cell development.^[8]