Inositol-trisphosphate 3-kinase B is an
enzyme that in humans is encoded by the ITPKBgene.[5][6]
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]
^Erneux C, Roeckel N, Takazawa K, Mailleux P, Vassart G, Mattei MG (Dec 1992). "Localization of the genes for human inositol 1,4,5-trisphosphate 3-kinase A (ITPKA) and B (ITPKB) to chromosome regions 15q14-q21 and 1q41-q43, respectively, by in situ hybridization". Genomics. 14 (2): 546–7.
doi:
10.1016/S0888-7543(05)80265-4.
PMID1330886.
Inositol-trisphosphate 3-kinase B is an
enzyme that in humans is encoded by the ITPKBgene.[5][6]
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]
^Erneux C, Roeckel N, Takazawa K, Mailleux P, Vassart G, Mattei MG (Dec 1992). "Localization of the genes for human inositol 1,4,5-trisphosphate 3-kinase A (ITPKA) and B (ITPKB) to chromosome regions 15q14-q21 and 1q41-q43, respectively, by in situ hybridization". Genomics. 14 (2): 546–7.
doi:
10.1016/S0888-7543(05)80265-4.
PMID1330886.