Interleukin-3, granulocyte-macrophage colony-stimulating factor, and interleukin-5 transduce signals through two forms of STAT5.
Recently, JAK2 kinase was found to be one of the tyrosine kinases activated by interleukin-3 (IL-3) in target cells. JAK2 belongs to a family of kinases that act upstream of transcription factors called STATs. STATs exist in the cytoplasm as latent, transcriptionally inactive forms until, in response to extracellular signals, they become phosphorylated on tyrosine residues, translocate to the nucleus, and bind to specific DNA elements. Because IL-3 activates JAK2, we searched for the STAT(s) that might transduce IL-3 signals. Several lines of evidence suggest that IL-3 uses the murine homologue of STAT5, a factor originally purified from sheep. Unexpectedly, during isolation of the murine homologue, we found two highly related molecules that we have designated STAT5A and STAT5B.
Mui
A L
AL
Department of Cell Biology, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, California.
Wakao
H
H
Harada
N
N
O'Farrell
A M
AM
Miyajima
A
A
D000818:Animals; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000502:physiology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000502:physiology*; D007377:Interleukin-3 / Q000502:physiology*; D015848:Interleukin-5 / Q000502:physiology*; D051379:Mice; D008894:Milk Proteins; D010766:Phosphorylation; D019000:Phosphotyrosine; D050799:STAT5 Transcription Factor; D012756:Sheep; D015398:Signal Transduction; D015534:Trans-Activators / Q000737:chemistry / Q000502:physiology*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
D004268:DNA-Binding Proteins; D007377:Interleukin-3; D015848:Interleukin-5; D008894:Milk Proteins; D050799:STAT5 Transcription Factor; C494093:Stat5a protein, mouse; C494096:Stat5b protein, mouse; D015534:Trans-Activators; D019000:Phosphotyrosine; D014443:Tyrosine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor