cdc2/pp56-62 are in vitro substrates for the tyrosine kinase encoded by the v-fms oncogene.
In eukaryotic cells, the serine-threonine-specific kinase cdc2 induces entry into mitosis by phosphorylation of several proteins including cyclin (pp62) with which it forms a tight complex. We show here that cdc2 and several phosphoproteins in the range of 56 to 62 kilodaltons (kDa), associated with cdc2, serve as in vitro substrates for the v-fms-specific tyrosine kinase. This is the first demonstration of in vitro phosphorylation of a physiologically relevant substrate through the v-fms specific kinase. In addition, cdc2 phosphorylated the v-fms polypeptides in serine and threonine residues. The biological significance of the mutual phosphorylations is discussed.
Tamura
T
T
Institut für Virologie, der Justus-Liebig-Universität Giessen, Federal Republic of Germany.
Simon
E
E
Geschwill
K
K
Niemann
H
H
D016203:CDC2 Protein Kinase; D016281:Oncogene Protein gp140(v-fms); D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000502:physiology*; D015682:Retroviridae Proteins, Oncogenic / Q000502:physiology*; D012694:Serine / Q000378:metabolism; D013912:Threonine / Q000378:metabolism
D016281:Oncogene Protein gp140(v-fms); D010750:Phosphoproteins; D015682:Retroviridae Proteins, Oncogenic; D013912:Threonine; D012694:Serine; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D016203:CDC2 Protein Kinase