Immunosuppressive Yersinia Effector YopM Binds DEAD Box Helicase DDX3 to Control Ribosomal S6 Kinase in the Nucleus of Host Cells

PLoS Pathog. 2016 Jun 14;12(6):e1005660. doi: 10.1371/journal.ppat.1005660. eCollection 2016 Jun.

Abstract

Yersinia outer protein M (YopM) is a crucial immunosuppressive effector of the plaque agent Yersinia pestis and other pathogenic Yersinia species. YopM enters the nucleus of host cells but neither the mechanisms governing its nucleocytoplasmic shuttling nor its intranuclear activities are known. Here we identify the DEAD-box helicase 3 (DDX3) as a novel interaction partner of Y. enterocolitica YopM and present the three-dimensional structure of a YopM:DDX3 complex. Knockdown of DDX3 or inhibition of the exportin chromosomal maintenance 1 (CRM1) increased the nuclear level of YopM suggesting that YopM exploits DDX3 to exit the nucleus via the CRM1 export pathway. Increased nuclear YopM levels caused enhanced phosphorylation of Ribosomal S6 Kinase 1 (RSK1) in the nucleus. In Y. enterocolitica infected primary human macrophages YopM increased the level of Interleukin-10 (IL-10) mRNA and this effect required interaction of YopM with RSK and was enhanced by blocking YopM's nuclear export. We propose that the DDX3/CRM1 mediated nucleocytoplasmic shuttling of YopM determines the extent of phosphorylation of RSK in the nucleus to control transcription of immunosuppressive cytokines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins / chemistry
  • Bacterial Outer Membrane Proteins / immunology
  • Bacterial Outer Membrane Proteins / metabolism*
  • Blotting, Western
  • Cell Line
  • Cell Nucleus / metabolism
  • Crystallography, X-Ray
  • DEAD-box RNA Helicases / chemistry
  • DEAD-box RNA Helicases / immunology
  • DEAD-box RNA Helicases / metabolism*
  • Fluorescent Antibody Technique
  • Gene Expression Regulation / physiology*
  • High-Throughput Nucleotide Sequencing
  • Host-Parasite Interactions / physiology
  • Humans
  • Immune Tolerance / physiology
  • Immunoprecipitation
  • Macrophages / microbiology
  • Mass Spectrometry
  • Microscopy, Confocal
  • Polymerase Chain Reaction
  • Protein Transport / physiology
  • Ribosomal Protein S6 Kinases, 90-kDa / biosynthesis*
  • Virulence Factors / immunology
  • Virulence Factors / metabolism
  • Yersinia Infections / immunology*
  • Yersinia Infections / metabolism
  • Yersinia enterocolitica

Substances

  • Bacterial Outer Membrane Proteins
  • Virulence Factors
  • yopM protein, Yersinia
  • RPS6KA1 protein, human
  • Ribosomal Protein S6 Kinases, 90-kDa
  • DDX3X protein, human
  • DEAD-box RNA Helicases

Grant support

MP is supported by the excellence cluster 'The Hamburg Centre for Ultrafast Imaging - Structure, Dynamics and Control of Matter at the Atomic Scale' of the Deutsche Forschungsgemeinschaft. AGK and DIS would like to acknowledge the EU FP7 Infrastructures Grant BioStructX (contract 283570). LB was supported by the Deutsche Forschungsgemeinschaft (GRK-1459). MH and MS were supported by DFG (He5875/1-1). AR was funded by the graduate school for Structure and Dynamics of Infection (SDI) of the Landesexellenzinitiative Hamburg (LEXI). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.