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Protein pyrophosphorylation by inositol pyrophosphates is a posttranslational event.

ABSTRACT: In a previous study, we showed that the inositol pyrophosphate diphosphoinositol pentakisphosphate (IP(7)) physiologically phosphorylates mammalian and yeast proteins. We now report that this phosphate transfer reflects pyrophosphorylation. Thus, proteins must be prephosphorylated by ATP to prime them for IP(7) phosphorylation. IP(7) phosphorylates synthetic phosphopeptides but not if their phosphates have been masked by methylation or pyrophosphorylation. Moreover, IP(7) phosphorylated peptides are more acid-labile and more resistant to phosphatases than ATP phosphorylated peptides, indicating a different type of phosphate bond. Pyrophosphorylation may represent a novel mode of signaling to proteins.

SUBMITTER: Bhandari R

PROVIDER: S-EPMC2000531 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Protein pyrophosphorylation by inositol pyrophosphates is a posttranslational event.

Bhandari Rashna R Saiardi Adolfo A Ahmadibeni Yousef Y Snowman Adele M AM Resnick Adam C AC Kristiansen Troels Z TZ Molina Henrik H Pandey Akhilesh A Werner J Kent JK Juluri Krishna R KR Xu Yong Y Prestwich Glenn D GD Parang Keykavous K Snyder Solomon H SH

Proceedings of the National Academy of Sciences of the United States of America 20070914 39

In a previous study, we showed that the inositol pyrophosphate diphosphoinositol pentakisphosphate (IP(7)) physiologically phosphorylates mammalian and yeast proteins. We now report that this phosphate transfer reflects pyrophosphorylation. Thus, proteins must be prephosphorylated by ATP to prime them for IP(7) phosphorylation. IP(7) phosphorylates synthetic phosphopeptides but not if their phosphates have been masked by methylation or pyrophosphorylation. Moreover, IP(7) phosphorylated peptides ...[more]

PMID: 17873058

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