Two novel variants of the v-src oncogene isolated from low and high metastatic RSV-transformed hamster cells.
Four different transformed cell lines were isolated as a result of independent infection of primary hamster fibroblasts by Rous sarcoma virus (RSV SR-D stocks). These lines differ by the level of their spontaneous metastatic activity: HET-SR-1, HET-SR-8, and HET-SR-10 cell lines induced 70-200 metastatic nodules in the lung and/or lymph nodes of inoculated animals (high metastatic lines, HM). Metastatic activity was not identified after injection of HET-SR cells (low metastatic line, LM). All cell lines contained one copy of integrated and expressed intact RSV provirus. The difference in the amount of v-src protein in cell lines was not correlated with their metastatic potential in vivo. Complete v-srcHM and v-srcLM genes were cloned from corresponding gene libraries and sequenced. In the unique region of both v-src isoforms a GC-rich insert of 60 nucleotides (20 a.a.) was found. The presence of this insert explains the unusual apparent molecular weight of protein encoded by v-srcHM and vsrcLM: 62 kDA. Both genes had 10 identical amino acid changes when compared to the known RSV SR-D v-src sequence. v-srcHM and v-srcLM differ by several amino acid changes. Most of them are localized in the unique domain and the extreme carboxy-terminal region of the of the oncoprotein. Both v-src variants and chimeric v-src with mutually substituted parts were subcloned in a retroviral vector and introduced into avian neuroretina cells. Significant differences in the morphology of transformed neuroretinal cells were associated with the mutations in the carboxy-terminal region of the v-src oncogene. Low metastatic HET-SR cells transfected with v-srcHM and the chimeric gene v-src-LH remarkably increased their metastatic potential. In contrast, this effect was not observed when the same cells were transfected with v-srcLM and the chimeric v-srcHL gene. Specific changes in the distribution of fibronectin matrix typical for high metastatic cells were found in the lines transfected with v-srcHM.
Tatosyan
A
A
Unité Mixte de Recherche 146 du CNRS, Institut Curie, Centre Universitaire, Orsay, France.
Yatsula
B
B
Shtutman
M
M
Moinova
E
E
Kaverina
I
I
Musatkina
E
E
Leskov
K
K
Mizenina
O
O
Zueva
E
E
Calothy
G
G
Dezélée
P
P
D000595:Amino Acid Sequence; D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics*; D001483:Base Sequence; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic; D002472:Cell Transformation, Viral; D002645:Chickens; D003001:Cloning, Molecular; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics; D005353:Fibronectins / Q000378:metabolism; D005814:Genes, Viral; D016391:Genes, src; D008647:Mesocricetus; D008969:Molecular Sequence Data; D009154:Mutation; D009362:Neoplasm Metastasis / Q000235:genetics*; D009374:Neoplasms, Experimental / Q000235:genetics / Q000821:virology*; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012160:Retina / Q000473:pathology
D004279:DNA, Viral; D005353:Fibronectins; D011993:Recombinant Fusion Proteins