Functional role of Tia1/Pub1 and Sup35 prion domains: directing protein synthesis machinery to the tubulin cytoskeleton

Mol Cell. 2014 Jul 17;55(2):305-18. doi: 10.1016/j.molcel.2014.05.027. Epub 2014 Jun 26.


Tia1/Pub1 is a stress granule component carrying a Q/N-rich prion domain. We provide direct evidence that Tia1 forms a prion in yeast. Moreover, Tia1/Pub1 acts cooperatively with release factor Sup35/eRF3 to establish a two-protein self-propagating state. This two-protein prion driven by the Q/N-rich prion domains of Sup35 and Tia1/Pub1 can be visualized as distinctive line structures along tubulin cytoskeleton. Furthermore, we find that tubulin-associated complex containing Pub1 and Sup35 oligomers normally exists in yeast, and its assembly depends on prion domains of Pub1 and Sup35. This Sup35/Pub1 complex, which also contains TUB1 mRNA and components of translation machinery, is important for the integrity of the tubulin cytoskeleton: PUB1 disruption and Sup35 depletion from the complex lead to cytoskeletal defects. We propose that the complex is implicated in protein synthesis at the site of microtubule assembly. Thus our study identifies the role for prion domains in the assembly of multiprotein complexes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyloid / metabolism
  • Animals
  • Cytoskeleton / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Peptide Termination Factors / chemistry
  • Peptide Termination Factors / metabolism*
  • Poly(A)-Binding Proteins / chemistry
  • Poly(A)-Binding Proteins / metabolism*
  • Prions / chemistry
  • Prions / metabolism*
  • Protein Biosynthesis
  • Protein Multimerization
  • Protein Structure, Tertiary
  • RNA, Fungal / metabolism
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / chemistry
  • RNA-Binding Proteins / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • T-Cell Intracellular Antigen-1


  • Amyloid
  • PUB1 protein, S cerevisiae
  • Peptide Termination Factors
  • Poly(A)-Binding Proteins
  • Prions
  • RNA, Fungal
  • RNA, Messenger
  • RNA-Binding Proteins
  • Recombinant Proteins
  • SUP35 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • T-Cell Intracellular Antigen-1
  • Tia1 protein, mouse
  • Tub1 protein, S cerevisiae
  • peptide-chain-release factor 3