Recombinant Retroviruses That Transduce Individual Polyoma Tumor Antigens: Effects on Growth and Differentiation

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 83; no. 12; pp. 4307 - 4311
• Main Authors: Cherington, Van, Morgan, Bill, Spiegelman, Bruce M., Roberts, Thomas M.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01.06.1986; National Acad Sciences
• Subjects: 3T3 cells; Adipocytes; Adipose Tissue - cytology; Animals; Antigens, Viral, Tumor - genetics; B lymphocytes; Biological and medical sciences; Biotechnology; Cell Cycle; Cell Differentiation; Cell growth; Cell Line; Cell lines; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Genes, Viral; Genetic engineering; Genetic technics; Genetic Vectors; Growth Substances - physiology; Infections; Methods. Procedures. Technologies; Mice; NIH 3T3 cells; Polyomavirus - genetics; Retroviral vectors; Retroviridae; Retroviridae - genetics; Transduction, Genetic; Vectors (cloning, transfer, expression). Insertion sequences and transposons; Viral tumor antigens; Adipocyte; Cell culture; Polyomavirus; Rodentia; Retroviridae; Papovaviridae; Cell differentiation; Genetic transfer; Virus; Vertebrata; Mammalia; Mouse; Oncogenic virus; Genetic engineering; T antigen; Vector
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.83.12.4307

We have constructed infectious retroviral vectors, derived from Moloney murine leukemia virus, that efficiently transduce the polyoma virus tumor (T) antigens individually. The parental vector we have chosen [pZIPNeoSV(X)1] expresses a dominant selectable marker for neomycin resistance and is a shuttle vector capable of propagation in both eukaryotic and prokaryotic cells, thus facilitating its use in structure-function studies. To address the relationship between polyoma T-antigen tumorigenesis and the effects of individual T antigens on growth control and differentiation, we used these vectors to introduce and stably express large, middle-sized, or small T antigens into mouse fibroblasts and preadipocytes. All cDNAs introduced into the vector are expressed stably even in the absence of selective pressure. The stable expression of small T antigen is noted particularly because cell lines expressing small T antigen have not been readily available prior to the use of retroviral vectors. Small T antigen-induced increase in saturation density of NIH 3T3 cells can be scored on the basis of the morphology of drug-resistant colonies. Middle-sized T antigen eliminates the growth requirement of NIH 3T3 cells for epidermal growth factor in a defined medium and permits growth in platelet-poor plasma, indicating elimination of the platelet-derived growth factor requirement as well. Large T antigen suppresses mouse preadipocyte (3T3-F442A) differentiation. These vectors and these functional assays of T-antigen activity permit genetic analysis of the relationship between tumorigenesis by T antigens and the alteration of cellular growth and differentiation.