In vivo functional analysis of the Ras exchange factor son of sevenless
AuthorsKarlovich, Chris A.
Rogge, Ronald D.
Czech, Michael P.
UMass Chan AffiliationsProgram in Molecular Medicine
Department of Biology and Molecular Biology
Graduate School of Biomedical Sciences
KeywordsAnimals; Binding Sites; Cell Membrane; Drosophila; *Drosophila Proteins; Eye Proteins; Guanine Nucleotide Exchange Factors; Insect Hormones; Membrane Glycoproteins; Membrane Proteins; Photoreceptors, Invertebrate; Proteins; Receptor Protein-Tyrosine Kinases; Signal Transduction; Son of Sevenless Proteins; ras Guanine Nucleotide Exchange Factors
Medicine and Health Sciences
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AbstractThe Son of sevenless (Sos) protein functions as a guanine nucleotide transfer factor for Ras and interacts with the receptor tyrosine kinase Sevenless through the protein Drk, a homolog of mammalian Grb2. In vivo structure-function analysis revealed that the amino terminus of Sos was essential for its function in flies. A molecule lacking the amino terminus was a potent dominant negative. In contrast, a Sos fragment lacking the Drk binding sites was functional and its activity was dependent on the presence of the Sevenless receptor. Furthermore, membrane localization of Sos was independent of Drk. A possible role for Drk as an activator of Sos is discussed and a Drk-independent interaction between Sos and Sevenless is proposed that is likely mediated by the pleckstrin homology domain within the amino terminus.
Science. 1995 Apr 28;268(5210):576-9.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/33940
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