title: [Karyotypic characteristics of the Chinese hamster cell line CHO-K1 resistant to colchicine].
abstract: Karyological analysis was made of G-banded chromosomes in the cells of three independent CHO-K1 clones stably resistant to colchicine (Clch) selected for resistance to Clch at the concentration 0.1 mkg/ml (the first step of selection), and of one clone with higher but unstable level of resistance (2 mkg/ml--the second level of resistance). The results obtained revealed a morphological instability of the P-shoulder of chromosome Z6: more often an additional genetical material (AGM) at the distal end (Z6+), or rarely deletions (Z6-). In cells of the stable resistant clones of the first step of selection the length of AGM and their morphological structures were shown to be constant, but differed among the clones. In cells of the higher resistant unstable clone the length of AGM and their morphological structure were different in different cells within the clone. The AGMs in the Clch-resistant cells are discussed in terms of possible amplification of gene(s) responsible for the Clch resistance. In the cell population of clone selected for the resistance to 2 mkg/ml of Clch the frequency of rearranged chromosomes was shown to increase. In cells of all the analysed resistant clones the chromosome Z16 was found to lose its p-shoulder.
mesh_terms: D000818:Animals; D002460:Cell Line; D002871:Chromosome Banding; D002999:Clone Cells / Q000187:drug effects / Q000648:ultrastructure*; D003078:Colchicine / Q000037:antagonists & inhibitors*; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D005784:Gene Amplification / Q000187:drug effects; D007621:Karyotyping
chemical_list: D003078:Colchicine
vernacular_title: Kariotipicheskie osobennosti kletok kitaĭskogo khomiachka linii CHO-K1, ustoĭchivykh k kolkhitsinu.