Recovery of the missing tumorigenicity in mitochondrial DNA-less HeLa cells by introduction of mitochondrial DNA from normal human cells
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The role of mitochondrial DNA (mtDNA) in the expression of the transformed phenotype was examined using mtDNA-less HeLa cells. Complete depletion of mtDNA and its products in the mtDNA-less HeLa cell line, EB8, was confirmed by Southern blot analysis and by [35S]methionine labeling of mitochondrially synthesized polypeptides. The tumorigenicity of the EB8 cells was assayed by inoculation of 1×107 cells subcutaneously into the backs of nude mice. The results showed that the tumorigenicity of HeLa cells was lost in good correspondence with the loss of mtDNA. However, the growth of EB8 cells in culture was very poor compared with that of HeLa cells, indicating that the apparent loss of tumorigenicity in EB8 cells could possibly be due to poor growth of the cells. Introduction of mtDNA from normal human fibroblasts into EB8 cells restored both the missing tumorigenicity and growth of the EB8 cells. These observations could be interpreted to show that mtDNA is required for expression of tumorigenicity, but that mutational changes of the mtDNA are not required for modulation of the phenotype in our experiments.
KeywordsBlot Analysis Polypeptide Methionine HeLa Cell Human Cell
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- 1.Pederson, P.L. (1978). InProceedings, Experimental Tumor Research, Vol. 22, (ed.) Wallach, D.F.H. (S. Karger AG, Basel), pp. 190–274.Google Scholar
- 2.Wilkinson, R., Hawks, A., and Pegg, A.N. (1975).Chem.-Biol. Interact. 9157–167.Google Scholar
- 14.Hayashi, J.-I., Yonekawa, H., Watanabe, S., Nonaka, I., Momoi, M.Y., Kagawa, Y., and Ohta, S. (1991). InProgress in Neuropathology, Vol. 7, (eds.) Sato, T., and DiMauro, S., (Raven Press, New York), pp. 93–102.Google Scholar
- 15.Hayashi, J.-I., and Murakami, J. (1988).Mol. Gen. Genet. 211381–385.Google Scholar
- 25.Shay, J.W., and Werbin, H. (1990). InMechanisms of Differentiation, Vol. I, (ed.) Fisher, P.B. (CRC Press, Boca Raton, Florida), pp. 135–159.Google Scholar