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Mammalian inositol polyphosphate multikinase synthesizes inositol 1,4,5-trisphosphate and an inositol pyrophosphate.

ABSTRACT: Using a consensus sequence in inositol phosphate kinase, we have identified and cloned a 44-kDa mammalian inositol phosphate kinase with broader catalytic capacities than any other member of the family and which we designate mammalian inositol phosphate multikinase (mIPMK). By phosphorylating inositol 4,5-bisphosphate, mIPMK provides an alternative biosynthesis for inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)]. mIPMK also can form the pyrophosphate disphosphoinositol tetrakisphosphate (PP-InsP(4)) from InsP(5). Additionally, mIPMK forms InsP(4) from Ins(1,4,5)P(3) and InsP(5) from Ins(1,3,4,5)P(4).

SUBMITTER: Saiardi A

PROVIDER: S-EPMC30134 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature

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Mammalian inositol polyphosphate multikinase synthesizes inositol 1,4,5-trisphosphate and an inositol pyrophosphate.

Saiardi A A Nagata E E Luo H R HR Sawa A A Luo X X Snowman A M AM Snyder S H SH

Proceedings of the National Academy of Sciences of the United States of America 20010213 5

Using a consensus sequence in inositol phosphate kinase, we have identified and cloned a 44-kDa mammalian inositol phosphate kinase with broader catalytic capacities than any other member of the family and which we designate mammalian inositol phosphate multikinase (mIPMK). By phosphorylating inositol 4,5-bisphosphate, mIPMK provides an alternative biosynthesis for inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)]. mIPMK also can form the pyrophosphate disphosphoinositol tetrakisphosphate (PP-InsP(4 ...[more]

PMID: 11226235

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