Microtubule disruption stimulates P-body formation

RNA. 2007 Apr;13(4):493-502. doi: 10.1261/rna.355807. Epub 2007 Feb 16.

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 alpha tubulin, TUB1 (tub1-724) stimulates P-body formation. Second, we find that the alpha-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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Benomyl / pharmacology
  • Fluorescent Dyes
  • Fungal Proteins / biosynthesis*
  • Green Fluorescent Proteins / metabolism
  • Indoles
  • Microtubules / drug effects
  • Microtubules / metabolism*
  • RNA, Messenger / metabolism
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / biosynthesis*
  • Temperature
  • Tubulin / genetics
  • Tubulin / metabolism
  • Tubulin Modulators / pharmacology

Substances

  • Fluorescent Dyes
  • Fungal Proteins
  • Indoles
  • RNA, Messenger
  • Saccharomyces cerevisiae Proteins
  • Tubulin
  • Tubulin Modulators
  • Green Fluorescent Proteins
  • DAPI
  • Benomyl