Microtubule-assisted mechanism for functional metabolic macromolecular complex formation

Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 07/2010; 107(29):12872-6. DOI: 10.1073/pnas.1008451107
Source: PubMed

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.

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