Ras-interacting domain of Ral GDP dissociation stimulator like (RGL) reverses v-Ras-induced transformation and Raf-1 activation in NIH3T3 cells.
Ral GDP dissociation stimulator (RalGDS) and RalGDS like (RGL) are putative effector proteins of Ras and contain the Ras-interacting domain (RID) at their C-terminal regions. v-Ras is known to activate c-fos promoter/enhancer and Raf-1 and to transform NIH3T3 cells. It is also known that v-Raf activates c-fos promoter/enhancer and transforms NIH3T3 cells. In this study, we examined the effect of RID on the phenotype of the cells transformed by v-Ras and v-Raf. Overexpression of RID greatly reduced cell growth in low serum, colony-forming activity in soft agar, c-fos promoter/enhancer activity, and Raf-1 activity of v-Ras-transformed cells. However, overexpression of RID did not affect the phenotype of v-Raf-transformed cells. These results clearly indicate that RID of RGL specifically binds to Ras in mammalian cells, that it blocks the signal from Ras to Raf-1, and that it reverses v-Ras-induced malignant phenotype. It has been reported that Ras-binding domains of Raf-1 and neurofibromatosis type 1 (NF1) reverse v-Ras-induced malignant phenotype. Since there is no homology in primary structures of RGL, Raf-1, and NF1, there may be a similarity of secondary or tertiary structure among RID of RGL and Ras-binding domains of Raf-1 and NF1, and the structure might be useful for developing a potential medicine for human cancers caused by Ras.
Okazaki
M
M
Department of Biochemistry, Hiroshima University School of Medicine, Japan.
Kishida
S
S
Murai
H
H
Hinoi
T
T
Kikuchi
A
A
D016475:3T3 Cells; D019883:Alkyl and Aryl Transferases; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002448:Cell Adhesion; D002455:Cell Division; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D051231:Farnesyltranstransferase; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic; D016514:Genes, Neurofibromatosis 1; D016762:Genes, fos; D011905:Genes, ras; D020662:Guanine Nucleotide Exchange Factors; D051379:Mice; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors; D015689:Oncogene Protein p21(ras) / Q000037:antagonists & inhibitors / Q000502:physiology*; D027384:Oncogene Proteins v-raf; D010446:Peptide Fragments / Q000096:biosynthesis / Q000235:genetics; D011401:Promoter Regions, Genetic; D017346:Protein Serine-Threonine Kinases / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D019908:Proto-Oncogene Proteins c-raf; D011994:Recombinant Proteins / Q000378:metabolism; D015682:Retroviridae Proteins, Oncogenic / Q000502:physiology; D013329:Structure-Activity Relationship; D014166:Transferases / Q000037:antagonists & inhibitors; D020725:ral GTP-Binding Proteins
D020662:Guanine Nucleotide Exchange Factors; D009363:Neoplasm Proteins; D010446:Peptide Fragments; D011518:Proto-Oncogene Proteins; C490771:RGL1 protein, human; D011994:Recombinant Proteins; D015682:Retroviridae Proteins, Oncogenic; C097104:Rgl1 protein, mouse; D014166:Transferases; D019883:Alkyl and Aryl Transferases; D051231:Farnesyltranstransferase; D027384:Oncogene Proteins v-raf; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D019204:GTP-Binding Proteins; D015689:Oncogene Protein p21(ras); D020725:ral GTP-Binding Proteins