Torso, a receptor tyrosine kinase required for embryonic pattern formation, shares substrates with the sevenless and EGF-R pathways in Drosophila.
The maternally expressed Drosophila gene torso (tor) is a receptor tyrosine kinase that, when activated, initiates a signal transduction cascade that is responsible for the proper differentiation of the terminal, nonsegmented regions of the embryo. l(1)pole hole, the Drosophila raf-1 serine-threonine kinase homolog, and corkscrew, a tyrosine phosphatase, have been shown previously to function in this signal transduction pathway. We have identified other products in this pathway by carrying out a mutagenesis screen for dominant suppressors of a tor gain-of-function allele. More than 40 mutations, some of which fall into seven complementation groups, have been characterized genetically. Two of these correspond to mutations in ras-1 and Son of sevenless (Sos), which also function in the sevenless and EGF receptor (Der) tyrosine kinase pathways. The phenotypes of several other Su(tor) mutations suggest that they also function in other receptor tyrosine kinase-activated pathways at different times during Drosophila development.
G.W. Hooper Foundation, University of California, San Francisco 94143-0552.
H J
HJ
Doyle
J M
JM
Bishop
D000483:Alleles; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D002874:Chromosome Mapping; D004330:Drosophila / Q000201:enzymology / Q000235:genetics*; D029721:Drosophila Proteins; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D017344:Genes, Insect; D005816:Genetic Complementation Test; D007301:Insect Hormones / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009024:Morphogenesis / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D021382:Protein Sorting Signals / Q000235:genetics / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D019908:Proto-Oncogene Proteins c-raf; D020794:Receptor Protein-Tyrosine Kinases; D015398:Signal Transduction / Q000235:genetics*; D020664:Son of Sevenless Proteins; D013379:Substrate Specificity; D013489:Suppression, Genetic; D013696:Temperature
D029721:Drosophila Proteins; D005136:Eye Proteins; D007301:Insect Hormones; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D011518:Proto-Oncogene Proteins; D020664:Son of Sevenless Proteins; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; C056737:sev protein, Drosophila; C080148:tor protein, Drosophila; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf