Identification of JAK/STAT signalling components by genome-wide RNA interference

Nature. 2005 Aug 11;436(7052):871-5. doi: 10.1038/nature03869.


Signalling pathways mediating the transduction of information between cells are essential for development, cellular differentiation and homeostasis. Their dysregulation is also frequently associated with human malignancies. The Janus tyrosine kinase/signal transducer and activator of transcription (JAK/STAT) pathway represents one such signalling cascade whose evolutionarily conserved roles include cell proliferation and haematopoiesis. Here we describe a systematic genome-wide survey for genes required for JAK/STAT pathway activity. Analysis of 20,026 RNA interference (RNAi)-induced phenotypes in cultured Drosophila melanogaster haemocyte-like cells identified interacting genes encoding 4 known and 86 previously uncharacterized proteins. Subsequently, cell-based epistasis experiments were used to classify these proteins on the basis of their interaction with known components of the signalling cascade. In addition to multiple human disease gene homologues, we have found the tyrosine phosphatase Ptp61F and the Drosophila homologue of BRWD3, a bromo-domain-containing protein disrupted in leukaemia. Moreover, in vivo analysis demonstrates that disrupted dBRWD3 and overexpressed Ptp61F function as suppressors of leukaemia-like blood cell tumours. This screen represents a comprehensive identification of novel loci required for JAK/STAT signalling and provides molecular insights into an important pathway relevant for human cancer. Human homologues of identified pathway modifiers may constitute targets for therapeutic interventions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / cytology
  • Drosophila melanogaster / enzymology
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism*
  • Epistasis, Genetic
  • Genome
  • Genomics*
  • Hemocytes / cytology
  • Hemocytes / enzymology
  • Hemocytes / metabolism
  • JNK Mitogen-Activated Protein Kinases / genetics
  • JNK Mitogen-Activated Protein Kinases / metabolism*
  • Phenotype
  • Protein Tyrosine Phosphatases / genetics
  • Protein Tyrosine Phosphatases / metabolism
  • Protein Tyrosine Phosphatases, Non-Receptor
  • RNA Interference*
  • STAT1 Transcription Factor
  • Signal Transduction*
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism


  • DNA-Binding Proteins
  • Drosophila Proteins
  • STAT1 Transcription Factor
  • Trans-Activators
  • Tumor Suppressor Proteins
  • JNK Mitogen-Activated Protein Kinases
  • Protein Tyrosine Phosphatases
  • Protein Tyrosine Phosphatases, Non-Receptor
  • Ptp61F protein, Drosophila