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Inositol polyphosphate multikinase is a nuclear PI3-kinase with transcriptional regulatory activity.

ABSTRACT: Phosphatidylinositol 3,4,5-trisphosphate is a major intracellular messenger molecule thought to be formed almost exclusively by cytosolic, wortmannin-inhibited phosphoinositide 3-kinase family members. Inositol polyphosphate multikinase was identified as an enzyme that generates a series of water-soluble inositol phosphates. We now report the robust, physiologic, and evolutionarily conserved phosphoinositide 3-kinase activity of inositol polyphosphate multikinase, which is localized to nuclei and unaffected by wortmannin. In yeast, this inositol lipid kinase activity physiologically regulates transcription.

SUBMITTER: Resnick AC

PROVIDER: S-EPMC1200306 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature

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Inositol polyphosphate multikinase is a nuclear PI3-kinase with transcriptional regulatory activity.

Resnick Adam C AC Snowman Adele M AM Kang Bingnan N BN Hurt K Joseph KJ Snyder Solomon H SH Saiardi Adolfo A

Proceedings of the National Academy of Sciences of the United States of America 20050825 36

Phosphatidylinositol 3,4,5-trisphosphate is a major intracellular messenger molecule thought to be formed almost exclusively by cytosolic, wortmannin-inhibited phosphoinositide 3-kinase family members. Inositol polyphosphate multikinase was identified as an enzyme that generates a series of water-soluble inositol phosphates. We now report the robust, physiologic, and evolutionarily conserved phosphoinositide 3-kinase activity of inositol polyphosphate multikinase, which is localized to nuclei an ...[more]

PMID: 16123124

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