Microtubule disruption stimulates P-body formation.
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.
Sweet
Thomas J
TJ
Center for RNA Molecular Biology, Case Western Reserve University, Cleveland, OH 44106, USA.
Boyer
Brooke
B
Hu
Wenqian
W
Baker
Kristian E
KE
Coller
Jeff
J
D000483:Alleles; D001542:Benomyl / Q000494:pharmacology; D005456:Fluorescent Dyes; D005656:Fungal Proteins / Q000096:biosynthesis*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007211:Indoles; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis*; D013696:Temperature; D014404:Tubulin / Q000235:genetics / Q000378:metabolism; D050257:Tubulin Modulators / Q000494:pharmacology
D005456:Fluorescent Dyes; D005656:Fungal Proteins; D007211:Indoles; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D014404:Tubulin; D050257:Tubulin Modulators; D049452:Green Fluorescent Proteins; C007293:DAPI; D001542:Benomyl