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Polyphosphate is a primordial chaperone.

ABSTRACT: Composed of up to 1,000 phospho-anhydride bond-linked phosphate monomers, inorganic polyphosphate (polyP) is one of the most ancient, conserved, and enigmatic molecules in biology. Here we demonstrate that polyP functions as a hitherto unrecognized chaperone. We show that polyP stabilizes proteins in vivo, diminishes the need for other chaperone systems to survive proteotoxic stress conditions, and protects a wide variety of proteins against stress-induced unfolding and aggregation. In vitro studies reveal that polyP has protein-like chaperone qualities, binds to unfolding proteins with high affinity in an ATP-independent manner, and supports their productive refolding once nonstress conditions are restored. Our results uncover a universally important function for polyP and suggest that these long chains of inorganic phosphate may have served as one of nature's first chaperones, a role that continues to the present day.

SUBMITTER: Gray MJ

PROVIDER: S-EPMC3996911 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Polyphosphate is a primordial chaperone.

Gray Michael J MJ Wholey Wei-Yun WY Wagner Nico O NO Cremers Claudia M CM Mueller-Schickert Antje A Hock Nathaniel T NT Krieger Adam G AG Smith Erica M EM Bender Robert A RA Bardwell James C A JC Jakob Ursula U

Molecular cell 20140220 5

Composed of up to 1,000 phospho-anhydride bond-linked phosphate monomers, inorganic polyphosphate (polyP) is one of the most ancient, conserved, and enigmatic molecules in biology. Here we demonstrate that polyP functions as a hitherto unrecognized chaperone. We show that polyP stabilizes proteins in vivo, diminishes the need for other chaperone systems to survive proteotoxic stress conditions, and protects a wide variety of proteins against stress-induced unfolding and aggregation. In vitro stu ...[more]

PMID: 24560923

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