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Microtubule-assisted mechanism for functional metabolic macromolecular complex formation.

ABSTRACT: Evidence has been presented for a metabolic multienzyme complex, the purinosome, that participates in de novo purine biosynthesis to form clusters in the cytoplasm of living cells under purine-depleted conditions. Here we identified, using fluorescent live cell imaging, that a microtubule network appears to physically control the spatial distribution of purinosomes in the cytoplasm. Application of a cell-based assay measuring the rate of de novo purine biosynthesis confirmed that the metabolic activity of purinosomes was significantly suppressed in the absence of microtubules. Collectively, we propose a microtubule-assisted mechanism for functional purinosome formation in HeLa cells.

SUBMITTER: An S

PROVIDER: S-EPMC2919939 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Microtubule-assisted mechanism for functional metabolic macromolecular complex formation.

An Songon S Deng Yijun Y Tomsho John W JW Kyoung Minjoung M Benkovic Stephen J SJ

Proceedings of the National Academy of Sciences of the United States of America 20100706 29

Evidence has been presented for a metabolic multienzyme complex, the purinosome, that participates in de novo purine biosynthesis to form clusters in the cytoplasm of living cells under purine-depleted conditions. Here we identified, using fluorescent live cell imaging, that a microtubule network appears to physically control the spatial distribution of purinosomes in the cytoplasm. Application of a cell-based assay measuring the rate of de novo purine biosynthesis confirmed that the metabolic a ...[more]

PMID: 20615962

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