Ala-->Gly mutation in the putative catalytic loop confers temperature sensitivity on Ros, insulin receptor, and insulin-like growth factor I receptor protein-tyrosine kinases.
Temperature-sensitive mutations in the avian sarcoma virus UR2 oncogene ros, encoding a receptor protein-tyrosine kinase (PTK), were identified. The Ala385-->Gly change mapping within the highly conserved RDLAARN motif in the Ros kinase domain was responsible for the temperature-sensitive phenotype. Based on the sequence homology of all known protein kinases and the crystalline structure of the cAMP-dependent protein kinase, this conserved region probably represents the PTK catalytic loop. The same mutation when introduced into the human insulin and insulin-like growth factor I receptors made these PTKs temperature sensitive in both biological function and kinase activity. Our results support the presumed catalytic role of this highly conserved sequence in PTKs. Due to its highly conserved nature, we predict that the same mutation would probably confer temperature sensitivity on other PTKs.
Chen
J
J
Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029.
Hanafusa
T
T
Wang
L H
LH
D000409:Alanine / Q000737:chemistry; D000595:Amino Acid Sequence; D001483:Base Sequence; D002471:Cell Transformation, Neoplastic; D017931:DNA Primers / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009856:Oncogene Proteins, Viral / Q000737:chemistry*; D020794:Receptor Protein-Tyrosine Kinases / Q000737:chemistry* / Q000378:metabolism; D017527:Receptor, IGF Type 2 / Q000737:chemistry*; D011972:Receptor, Insulin / Q000737:chemistry*; D011993:Recombinant Fusion Proteins; D013329:Structure-Activity Relationship; D013696:Temperature
D017931:DNA Primers; D009856:Oncogene Proteins, Viral; D017527:Receptor, IGF Type 2; D011993:Recombinant Fusion Proteins; D020794:Receptor Protein-Tyrosine Kinases; D011972:Receptor, Insulin; C058682:v-ros protein, Avian sarcoma virus UR2; D000409:Alanine; D005998:Glycine