Expression pattern and first functional characterization of riok-1 in Caenorhabditis elegans

Gene Expr Patterns. 2014 Jul;15(2):124-34. doi: 10.1016/j.gep.2014.05.005. Epub 2014 Jun 12.


Rio kinases are atypical serine/threonine kinases that emerge as potential cooperation partners in Ras-driven tumors. In the current study, we performed an RNAi screen in Caenorhabditis elegans to identify suppressors of oncogenic Ras signaling. Aberrant Ras/Raf signaling in C. elegans leads to the formation of a multi-vulva (Muv) phenotype. We found that depletion of riok-1, the C. elegans orthologue of the mammalian RioK1, suppressed the Muv phenotype. By using a promoter GFP construct, we could show that riok-1 is expressed in neuronal cells, the somatic gonad, the vulva, the uterus and the spermatheca. Furthermore, we observed developmental defects in the gonad upon riok-1 knockdown in a wildtype background. Our data suggest that riok-1 is a modulator of the Ras signaling pathway, suggesting implications for novel interventions in the context of Ras-driven tumors.

Keywords: Gonad development; LET-60; Multi-vulva phenotype; RIOK-1; RNAi screen; Vulval development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Butadienes / chemistry
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans Proteins / metabolism*
  • Cell Lineage
  • Enzyme Inhibitors / chemistry
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Gene Expression Profiling*
  • Gene Expression Regulation, Developmental*
  • Gene Expression Regulation, Enzymologic*
  • Gonads / embryology
  • Molecular Sequence Data
  • Neurons / metabolism
  • Nitriles / chemistry
  • Phenotype
  • Protein-Serine-Threonine Kinases / metabolism*
  • RNA Interference
  • Signal Transduction
  • Time Factors


  • Butadienes
  • Caenorhabditis elegans Proteins
  • Enzyme Inhibitors
  • Nitriles
  • U 0126
  • Protein-Serine-Threonine Kinases
  • Extracellular Signal-Regulated MAP Kinases