Abstract
SEWATC13 mouse cells, resistant to 0.1 μg/ml of actinomycin D (AMD), were fused to AMD-sensitive cells of the Chinese hamster ovary cell line (CHO). Twentytwo hybrid clones were isolated and put into serial culture in the selective medium. Unexpectedly, identifiable mouse chromosomes were found only in one of the hybrids. All the others had only hamster chromosomes and, in addition, numerous chromatin bodies (CBs), mostly small and irregularly shaped, but also larger, more chromosome-like ones. The CBs were distinctly C-band positive and a mouse satellite probe hybridized strongly to them. The AMD resistance of the murine parental cells had previously been attributed to gene amplification in two large homogeneously staining regions (HSR-AMD1 and 2). They were not observed in the hybrid cells but had supposedly reappeared in the guise of the CBs. It was established by Southern DNA blot analysis that amplified DNA sequences, localized to the HSRAMD1 and 2 of the SEWA parent were present in multiple copies in the hybrids. It was also established by in situ hybridization that they were located in the CBs. Unlike double minutes (DMs) the CBs were all centric.
Similar content being viewed by others
References
Arnason U, Manolova Y, Manolov G, Bregula U, Levan A (1986) Satellite DNA in three C-bands of an unusual mouse marker chromosome: A model of chromosomal evolution. Exp Cell Res 164:256–260
Battey J, Moulding C, Taub R, Murphy W, Stewart T, Potter H, Lenoir G, Leder P (1983) The human c-myc oncogene: Structural consequences of translocation into the IGH locus in Burkitt lymphoma. Cell 34:779–787
Blin N, Stafford DW (1976) Isolation of high molecular weight DNA. Nucleic Acids Res 3:2303–2308
Dahllöf B, Martinsson T, Levan G (1984) Resistance to actinomycin D and vincristine induced in a cell line from the SEWA mouse ascites tumor with concomitant appearance of double minutes and a low molecular weight protein. Exp Cell Res 152:415–426
Deaven LL, Petersen DF (1973) The chromosomes of CHO, an aneuploid Chinese hamster cell line: G-band, C-band and autoradiographic analyses. Chromosoma 41:129–144
Gerlach JH, Kartner N, Bell DR, Ling V (1986) Multidrug resistance. Cancer Surv 5:25–46
Jakobsson A-H, Dahllöf B, Martinsson T, Levan G (1983) Transfer of methotrexate resistance by somatic cell hybridization. Hereditas 99:293–302
Kao F, Puck TT (1969) Genetics of somatic mammalian cells. IX. Quantitation of mutagenesis by physical and chemical agents. J Cell Physiol 74:245–253
Kopnin BP, Gudkov AA (1982) Gene amplification in mammalian somatic cells resistant to colchicine. III. Localization of duplicated genes in small chromatin bodies. Genetika 18:1683–1692
Levan A, Levan G (1978) Have double minutes functioning centromeres? Hereditas 88:81–92
Martinsson T, Levan G (1987) Localization of the multidrug-resistance associated 170 kDa P-glycoprotein gene to chromosome 5 in the mouse, and to homogeneously staining regions in multidrug-resistant mouse cells by in situ hybridization. Cytogenet Cell Genet, in press
Martinsson T, Tenning P, Lundh L, Levan G (1982) Methotrexate resistance and double minutes in a cell line from the SEWA mouse ascites tumor. Hereditas 97:123–137
Martinsson T, Dahllöf B, Wettergren Y, Leffler H, Levan G (1985a) Pleiotropic drug resistance and gene amplification in a SEWA mouse tumor cell line: Complex relations revealed by drug uptake and lipid and protein analyses. Exp Cell Res 158:382–394
Martinsson T, Stahl F, Levan G (1985b) Chromosomal localization of amplified DNA sequences in mouse tumor cells. Anticancer Res 5:630
Puck TT, Cieciura SJ, Robinson A (1958) Genetics of mammalian cells. III. Long term cultivation of euploid cells from human and mammalian subjects. J Exp Med 108:945–956
Ray M, Mohandas T (1976) Proposed banding nomenclature for the Chinese hamster chromosomes. Cytogenet Cell Genet 16:83–91
Stahl F, Sandberg P, Martinsson T, Wettergren Y, Bjursell G, Levan G (1987) Isolation of selectively amplified DNA sequences from multidrug-resistant SEWA cells. Hereditas 106:97–105
Sobel J, Albrecht AM, Riehm M, Biedler JL (1971) Hybridization of actinomycin D- and amethopterin-resistant Chinese hamster cells in vitro. Cancer Res 31:153–161
Southern EM (1975) Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol 98:503–517
Sumner AT (1972) A simple technique for demonstrating centromeric heterochromatin. Exp Cell Res 75:304–306
Van der Bliek AM, Van der Velde-Koerts T, Ling V, Borst P (1986) The overexpression and amplification of five genes in a multidrug-resistant Chinese hamster ovary cell line. Mol Cell Biol 6:1671–1678
Vig BK (1984) Sequence of centromere separation: Orderly separation of multicentric chromosomes in mouse L-cells. Chromosoma 90:39–45
Vig BK, Zinkowski RP (1986) Sequence of centromere separation: A mechanism for orderly separation in dicentrics. Cancer Genet Cytogenet 22:347–359
Worton RG, Ho CC, Duff C (1977) Chromosome stability in CHO cells. Somatic Cell Genet 3:27–45
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Jakobsson, AH., Arnason, U., Levan, A. et al. Novel cytogenetic expression of gene amplification in actinomycin D-resistant somatic cell hybrids: transfer of resistance by centric chromatin bodies. Chromosoma 95, 408–418 (1987). https://doi.org/10.1007/BF00333992
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00333992