title: Progenitor expansion in apc mutants is mediated by Jak/Stat signaling.
abstract: BACKGROUND
  Mutations in APC, a negative regulator of the Wnt/ß-catenin pathway, can cause cancer as well as profound developmental defects. In both cases, affected cells adopt a proliferative progenitor state and fail to differentiate. While the upregulation of some target genes of Wnt/ß-catenin signaling has been shown to mediate these phenotypes in individual tissues, it is unclear whether a common mechanism underlies the defects in APC mutants.
  
  
  RESULTS
  Here we show that stat3, a known oncogene and a target of ß-catenin in multiple tissues, is upregulated in apc mutant zebrafish embryos. We further demonstrate that Jak/Stat signaling is necessary for the increased level of proliferation and neural progenitor gene expression observed in apc mutants.
  
  
  CONCLUSIONS
  Together, our data suggest that the regulation of Jak/Stat signaling may represent a conserved mechanism explaining the expansion of undifferentiated cells downstream of APC mutations.
authors.affiliation: Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
authors.forename: Junji
authors.initials: J
authors.lastname: Lin
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Richard I
authors.initials: RI
authors.lastname: Dorsky
mesh_terms: D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D004625:Embryo, Nonmammalian / Q000378:metabolism; D053612:Janus Kinases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D058953:Neural Stem Cells / Q000166:cytology / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D015533:Transcriptional Activation; D060449:Wnt Signaling Pathway / Q000235:genetics; D015027:Zebrafish / Q000196:embryology / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D025601:Adenomatous Polyposis Coli Protein; D050796:STAT3 Transcription Factor; D029961:Zebrafish Proteins; C494089:stat3 protein, zebrafish; D053612:Janus Kinases