The cAMP-dependent Protein Kinase Signaling Pathway Is a Key Regulator of P Body Foci Formation

Mol Cell. 2011 Sep 16;43(6):973-81. doi: 10.1016/j.molcel.2011.06.032.

Abstract

In response to stress, eukaryotic cells accumulate mRNAs and proteins at discrete sites, or foci, in the cytoplasm. However, the mechanisms regulating foci formation, and the biological function of the larger ribonucleoprotein (RNP) assemblies, remain poorly understood. Here, we show that the cAMP-dependent protein kinase (PKA) in Saccharomyces cerevisiae is a key regulator of the assembly of processing bodies (P bodies), an RNP complex implicated in mRNA processing and translation. The data suggest that PKA specifically inhibits the formation of the larger P body aggregates by directly phosphorylating Pat1, a conserved constituent of these foci that functions as a scaffold during the assembly process. Finally, we present evidence indicating that P body foci are required for the long-term survival of stationary phase cells. This work therefore highlights the general relevance of RNP foci in quiescent cells, and provides a framework for the study of the many RNP assemblies that form in eukaryotic cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Cyclic AMP-Dependent Protein Kinases / physiology*
  • DEAD-box RNA Helicases / metabolism
  • Phosphorylation
  • Protein Biosynthesis
  • Protein-Serine-Threonine Kinases / metabolism
  • RNA Processing, Post-Transcriptional
  • RNA, Fungal / metabolism
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / metabolism
  • Ribonucleoproteins / metabolism
  • Ribonucleoproteins / physiology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Saccharomyces cerevisiae Proteins / physiology*
  • Signal Transduction
  • Transcription Factors / metabolism

Substances

  • PAT1 protein, S cerevisiae
  • RNA, Fungal
  • RNA, Messenger
  • RNA-Binding Proteins
  • Ribonucleoproteins
  • Saccharomyces cerevisiae Proteins
  • TORC1 protein complex, S cerevisiae
  • Transcription Factors
  • SNF1-related protein kinases
  • Protein-Serine-Threonine Kinases
  • Cyclic AMP-Dependent Protein Kinases
  • DHH1 protein, S cerevisiae
  • DEAD-box RNA Helicases