Microtubule disruption stimulates P-body formation (original) (raw)
- Thomas J. Sweet,
- Brooke Boyer,
- Wenqian Hu,
- Kristian E. Baker, and
- Jeff Coller
- Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, Ohio 44106, USA
Abstract
Processing bodies (P-bodies) are subcellular ribonucleoprotein (RNP) granules that have been hypothesized to be sites of mRNA degradation, mRNA translational control, and/or mRNA storage. Importantly, P-bodies are conserved from yeast to mammals and contain a common set of evolutionarily conserved protein constituents. P-bodies are dynamic structures and their formation appears to fluctuate in correlation with alterations in mRNA metabolism. Despite these observations, little is understood about how P-body structures are formed within the cell. In this study, we demonstrate a relationship between P-bodies and microtubules in the budding yeast, Saccharomyces cerevisiae. First, we demonstrate that disruption of microtubules by treatment with the drug benomyl leads to aggregation of P-body components. Consistent with this finding, we also demonstrate that disruption of microtubules by a temperature-sensitive allele of the major α tubulin, TUB1 (tub1–724) stimulates P-body formation. Second, we find that the α-tubulin protein Tub1 colocalizes with P-bodies upon microtubule destabilization. Third, we determine that a putative tubulin tyrosine ligase, encoded by YBR094W, is a protein component of P-bodies, providing additional evidence for a physical connection between P-bodies and microtubules. Finally, we establish that P-bodies formed by microtubule destabilization fail to correlate with global changes in the stability of mRNA or in general mRNA translation. These findings demonstrate that the aggregation of P-body components is linked to the intracellular microtubule network, and, further, that P-bodies formed by disruption of microtubules aggregate independent of broad alterations in either mRNA decay or mRNA translation.
Footnotes
Reprint requests to: Jeff Coller, Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, OH 44106, USA; e-mail: jmc71{at}case.edu; fax: (216) 368-2010.
Article published online ahead of print. Article and publication date are at http://www.rnajournal.org/cgi/doi/10.1261/rna.355807.
- Received October 19, 2006.
- Accepted January 10, 2007.
Copyright © 2007 RNA Society