DNA Repair Genes of Mammalian Cells
In the Chinese hamster ovary (CHO) cell line, various mutations affecting DNA repair have been obtained. Mutants that belong to 5 genetic complementation groups for ultraviolet (UV) sensitivity and resemble the cells from individuals having the cancer-prone genetic disorder xeroderma pigmentosum (XP) were previously identified. Each mutant is defective in the incision step of nucleotide excision repair and hypersensitive to bulky DNA lesions. These UV mutants can be divided into two subgroups; only Groups 2 and 4 are extremely sensitive to mitomycin C and other DNA crosslinking agents.
The clear-cut phenotypes of the CHO mutants have allowed us to construct hybrid cells by fusion with human Ijnnphocytes and thereby identify which human chromosomes carry genes that correct the CHO mutations. The first two mutations analyzed, UV20 (excision-repair deficient; UV Group 2) and EM9, which has a very high frequency of sister chromatid exchange (SCE), are both corrected by chromosome 19.
Efforts are underway to isolate complementing repair genes by DNA-mediated gene transfer. The human gene that corrects mutant EM9 and the hamster gene that corrects UV135 (UV Group 5) have been introduced by cotransfer of genomic DNA and the dominant selectable marker gpt (guanine phosphoribosyltransferase) gene. In each case, the DNA repair function was co-selected based on resistance to 5-chlorodeoxyuridine (CldUrd) or repeated UV irradiation, respectively. The presence of a functional human repair gene in the EM9 transformants is shown by the presence of common human DNA sequences on some fragments produced by restriction enzyme cleavage. In UV135, transfer of a repair gene is indicated by a colony distribution containing “jackpots” and by instability of the resistant phenotype.
KeywordsRepair Gene Sister Chromatid Exchange Xeroderma Pigmentosum Complementation Group Chinese Hamster Ovary Cell Line
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- 1.Abraham, I. (1985) DNA-mediated gene transfer. In Molecular Cell Genetics, M.M. Gottesman, ed. John Wiley, New York, pp. 181–210.Google Scholar
- 3.Chan, J.Y.H., L.H. Thompson, and F.F. Becker (1984) DNA ligase activities appear normal in the CHO mutant EM9. Mutat. Res. 131:209–214.Google Scholar
- 4.Cleaver, J.E. (1983) Xeroderma pigmentosum. In The Metabolic Basis of Inherited Disease, 5th ed., J.B. Stanbury, J.B. Wyngaarden, D.S. Fredrickson, J.L. Goldstein, and M.S. Brown, eds. McGraw-Hill, New York, pp. 1227–1248.Google Scholar
- 6.Dillehay, L.E., L.H. Thompson, and A.V. Carrano (1984) DNA strand breaks associated with halogenated pyrimidine incorporation. Mutat. Res. 131:129–136.Google Scholar
- 7.Fischer, E., W. Keijzer, H.W. Thielmann, O. Popanda, E. Bohnert, L. Edler, E.G. Jung, and D. Bootsma (1985) A ninth complementation group in xeroderma pigmentosum. Mutat. Res. 145:217–225.Google Scholar
- 10.Hoy, C.A., E.P. Salazar, and L.H. Thompson (1984) Rapid detection of DNA-damaging agents using repair-deficient CHO cells. Mutat. Res. 130:321–332.Google Scholar
- 11.Hoy, C.A., L.H. Thompson, C.A. Mooney, and E.P. Salazar (1985) Defective DNA cross-link removal in Chinese hamster cell mutants hypersensitive to bifunctional alkylating agents. Cancer Res. 45:1737–1743.Google Scholar
- 13.Jeggo, P.A., and L.M. Kemp (1983) X-ray sensitive mutants of Chinese hamster ovary cell line: Isolation and cross-sensitivity to other DNA-damaging agents. Mutat. Res. 112:313–327.Google Scholar
- 14.Karentz, D., and J.E. Cleaver (1985) Transfer of Chinese hamster DNA repair gene(s) into repair-deficient human cells (xeroderma pigmento- sum). Abstract, Thirty-Third Ann. Mtg. Radiat. Res. Soc., Los Angeles, California, p. 92.Google Scholar
- 15.Kemp, L.M., S.G. Sedgwick, and P.A. Jeggo (1984) X-ray sensitive mutants of Chinese hamster ovary cells defective in double-strand break rejoining. Mutat. Res. 132:189–196.Google Scholar
- 18.Lambert, W.C., and M.W. Lambert (1985) Co-recessive inheritance: A model for DNA repair, genetic disease and carcinogenesis. Mutat. Res. 145:227–234.Google Scholar
- 20.Macinnes, M.A., J.M. Bingham, L.H. Thompson, and G.F. Strniste (1984) DNA-mediated co-transfer of excision repair capacity and drug resistance into Chinese hamster ovary mutant cell line UV-135. Mol. Cell. Biol. 4:1152–1158.Google Scholar
- 22.Maher, V.M., and J.J. McCormick (1984) Role of DNA lesions and excision repair in carcinogen-induced mutagenesis and transformation. In Biochemical Basis of Chemical Carcinogenesis, H. Greim, R. Jung, M. Kramer, H. Marquardt, and F. Oesch, eds. Raven Press, New York, pp. 143–159.Google Scholar
- 25.Pinkel, D., L.H. Thompson, J.W. Gray, and M. Vanderlaan (1985) Measurement of sister chromatid exchanges at very low Brd Und substitution levels using a monoclonal antibody. Cancer Res. 45:5795–5798.Google Scholar
- 27.Sato, K., and N. Hieda (1979) Isolation of a mammalian cell mutant sensitive to 4-nitroquinoline-l-oxide. Int. J. Radiat. Biol. 35:83- 87.Google Scholar
- 31.Siciliano, M.J., A.V. Carrano, and L.H. Thompson (1985) Assignment of a human DNA repair gene associated with sister chromatid exchange to chromosome 19. Science (Manuscript submitted for publication.)Google Scholar
- 38.Thompson, L.H., K.W. Brookman, L.E. Dillehay, A.V. Carrano, J.A. Mazrimas, C.L. Mooney, and J.L. Minkler (1982) A CHO-cell strain having hypersensitivity to mutagens, a defect in DNA strand-break repair, and an extraordinary baseline frequency of sister chromatid exchange. Mutat. Res. 95:427–440.CrossRefGoogle Scholar
- 39.Thompson, L.H., and A.V. Carrano (1983) Analysis of mammalian cell mutagenesis and DNA repair using vitro selected CHO cell mutants. In Cellular Responses to DNA Damage, E.C. Friedberg and B.R. Bridges, eds. Alan R. Liss, Inc., New York, pp. 125–143.Google Scholar
- 41.Thompson, L.H., K.W. Brookman, J.L. Minkler, J.C. Fuscoe, K.A. Henning, and A.V. Carrano (1985) DNA-mediated transfer of a human DNA repair gene that controls sister chromatid exchange, Mol. Cell. Biol. 5:881–884.Google Scholar
- 43.Ullu, E., and C. Tschudi (1984) Alu sequences are processed 7SL RNA Nature 312:171–172.Google Scholar
- 44.Waldren, C.A., D. Snead, and T. Stamato (1983) Restoration of normal resistance to killing and of postreplication recovery (PRR) in CHO- UV-1 cells by transformation with hamster or human DNA. In Cellular Responses to DNA Damage, E.C. Friedberg and B.R. Bridges, eds. Alan R. Liss, Inc., New York, pp. 637–646.Google Scholar
- 47.Zdzienicka, M.Z., and J.W.I.M. Simons (1985) Analysis of repair processes by the determination of the induction of cell killing and mutations in two repair deficient Chinese hamster ovary cell lines. (Manuscript submitted for publication.)Google Scholar