Abstract
We studied the early stages of gene amplification in a Chinese hamster cell line and identified two distinct amplification mechanisms, both relying on an unequal segregation of gene copies at mitosis. In some cases, a sequence containing the selected gene is looped out, generating an acentric circular molecule, and amplification proceeds through unequal segregation of such extrachromosomal elements in successive cell cycles. In other cases, the accumulation of intrachromosomally amplified copies is driven by cycles of chromatid breakage, followed by fusion of sister chromatids devoid of a telomere, which leads to bridge formation and further break in mitosis (BFB cycles). We showed that some clastogenic drugs specifically trigger the intrachromosomal amplification pathway and strictly correlated this induction of BFB cycles to the ability of these drugs to activate fragile sites. In three model systems, we also established, that the location of centromeric and telomeric fragile sites relative to the selected genes determines the size and sequence content of the early amplicons.
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References
Bertoni L, Attolini C, Tessera L, Mucciolo E, Giulotto E (1994) Role of telomeric and nontelomeric ( TTAGGG)n sequences in gene amplification and chromosome stability. Genomics 24: 53–62
Biedler JL, Meyers MB (1989) Multidrug resistance (vinca alkaloids, actinomycin D, and anthracycline antibiotics). In: Gupta RS (ed) Drug resistance in mammalian cells. CRC, Boca Raton, 2: 57–88
Brison O (1993) Gene amplification and tumor progression. Biochim Biophys Acta 1155: 25–41
Coquelle A, Pipiras E, Toledo F, Buttin G, Debatisse M (1997) Expression of fragile sites triggers intrachromosomal mammalian gene amplification and sets boundaries to early amplicons. Cell 89: 215–225
Cowell J (1982) Double minutes and homogeneously staining regions: gene amplification in mammalian cells. Annu Rev Genet 16: 21–59
Hartwell L (1992) Defects in a cell cycle checkpoint may be responsible for the genomic instability of cancer cells. Cell 71: 543–546
Kuo MT, Vyas RC, Jiang LX, Hittelman WN (1994) Chromosome breakage at a major fragile site associated with P-glycoprotein gene amplification in multidrug-resistant CHO cells. Mol Cell Biol 14: 5202–5211
Livingstone LR, White A, Sprouse J, Livanos E, Jacks T, Tlsty TD (1992) Cell cycle arrest and gene amplification potential accompany loss of wild-type p53. Cell 70: 923–935
Ma C, Martin S, Trask B, Hamlin JL (1993) Sister chromatid fusion initiates amplification of the dihydrofolate reductase gene in chinese hamster cells. Genes Dev. 7: 605–620
McClintock B (1942) The fusion of broken ends of chromosomes following nuclear fusion. Proc Natl Acad Sci USA 28: 458–463
Pinkel D, Landegent J, Collins C, Fuscoe J, Segraves R, Lucas J, Gray J (1988) Fluorescence in situ hybridization with human chromosome-specific libraries: detection of trisomy 21 and translocations of chromosome 4. Proc Natl Acad Sci USA 85: 9138–9142
Pipiras E, Coquelle A, Bieth A, Debatisse M (1998) Interstitial deletions and intrachromosomal amplification initiated from a double-strand break targeted to a mammalian chromosome. EMBO J 17: 325–333
Schwab M, Amler LC (1990) Amplification of cellular oncogenes: a predictor of clinical outcome in human cancer. Genes Chromosomes Cancer 1: 181–193
Smith KA, Gorman PA, Stark MB, Groves RP, Stark GR (1990) Distinctive chromosomal structures are formed very early in the amplification of CAD genes in Syrian hamster cells. Cell 63: 1219–1227
Smith KA, Stark MB, Gorman PA, Stark GR (1992) Fusion near telomeres occur very early in the amplification of CAD genes in Syrian hamster cells. Proc Natl Acad Sci USA 89: 5427–5431
Stahl F, Wettergren Y, Levan G (1992) Amplicon structure in multi-drug-resistant murine cells: a non-rearranged region of genomic DNA corresponding to large circular DNA. Mol Cell Biol 12: 1179–1187
Toledo F, LeRoscouet D, Buttin G, Debatisse M (1992a) Co-amplified markers alternate in megabase long chromosomal inverted repeats and cluster independently in interphase nuclei at early steps of mammalian gene amplification. EMBO J 11: 2665–2673
Toledo F, Smith KA, Buttin G, Debatisse M (1992b) The evolution of the amplified adenylate deaminase 2 domains in Chinese hamster cells suggests the sequential operation of different mechanisms of DNA amplification. Mutat Res 276: 261–273
Toledo F, Buttin G, Debatisse M (1993) The origin of chromosome rearrangements at early stages of AMPD2 gene amplification in Chinese hamster cells. Curr Biol 3: 255–264
Trask B, Hamlin J (1989) Early dihydrofolate reductase gene amplification events in CHO cells usually occur on the same chromosome arm as the original locus. Genes Dev 3: 1913–1925
Yin Y, Tainsky MA, Bischoff FZ, Strong LC, Wahl GM (1992) Wild-type p53 restores cell cycle control and inhibits gene amplification in cells with mutant p53 alleles. Cell 70: 937–948
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© 1998 Springer-Verlag Berlin · Heidelberg
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Debatisse, M., Coquelle, A., Toledo, F., Buttin, G. (1998). Gene Amplification Mechanisms: The Role of Fragile Sites. In: Schwab, M., Rabes, H.M., Munk, K., Hofschneider, H.P. (eds) Genes and Environment in Cancer. Recent Results in Cancer Research, vol 154. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-46870-4_13
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DOI: https://doi.org/10.1007/978-3-642-46870-4_13
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