Co-operation in cell transformation between BK virus and the human c-Harvey-ras oncogene.
Early-passage hamster embryo cells were transformed by recombinant DNA molecules containing BK virus (BKV) early-region gene and either the activated c-Ha-ras oncogene (pBK/c-rasA) or the normal c-Ha-ras proto-oncogene (pBK/c-rasN). The recombinant DNAs had a greater transforming ability and converted hamster cells to a more malignant phenotype than the single genes transfected separately. pBK/c-rasA was significantly more powerful than pBK/c-rasN in conferring to cells all the characteristics of transformation. Transfected DNA sequences were integrated mostly as single insertions into cellular DNA. Specific c-Ha-ras and BKV transcripts as well as c-Ha-ras p21 and BKV T antigen were detected in transformed cells. Although stimulation of c-Ha-ras expression by BKV enhancers cannot be excluded in recombinants, super-transfection and co-transfection experiments in hamster embryo cells and pre-neoplastic cell lines showed that BKV early-region and c-Ha-ras co-operate in transformation by contributing separate and independent functions.
Pagnani
M
M
Institute of Microbiology, School of Medicine, University of Ferrara, Italy.
Corallini
A
A
Caputo
A
A
Altavilla
G
G
Selvatici
R
R
Catozzi
L
L
Possati
L
L
Barbanti-Brodano
G
G
D000818:Animals; D000957:Antigens, Viral, Tumor / Q000032:analysis; D001739:BK Virus / Q000235:genetics* / Q000276:immunology; D002471:Cell Transformation, Neoplastic; D006224:Cricetinae; D004279:DNA, Viral / Q000032:analysis; D005822:Genetic Vectors; D011120:Polyomavirus / Q000235:genetics*; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000032:analysis; D016283:Proto-Oncogene Proteins p21(ras); D011519:Proto-Oncogenes; D014158:Transcription, Genetic; D014162:Transfection
D000957:Antigens, Viral, Tumor; D004279:DNA, Viral; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras)