title: Chromosome aberrations associated with CAD gene amplification in Chinese hamster cultured cells.
abstract: Eleven sublines with increasing resistance to N-phosphonacetyl-L-aspartate (PALA) were isolated from the V79,B7 Chinese hamster cell line. Aspartate transcarbamylase activity and CAD gene copy number increased with increasing resistance of sublines. In situ hybridization with a DNA probe for the CAD gene showed that the amplified sequences resided in the terminal region of a marker chromosome with elongated q arms. This region stained homogeneously after G-banding. A high incidence of both numerical and structural chromosome aberrations was found in PALA-resistant cells. In hyperdiploid and polyploid cells, containing 2 copies of the marker chromosome, dicentrics were found at a very high frequency. As indicated by in situ hybridization and G-banding, they originated from a rearrangement involving 2 homologous marker chromosomes.
mesh_terms: D000818:Animals; D001221:Aspartate Carbamoyltransferase / Q000235:genetics; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing) / Q000235:genetics; D002460:Cell Line; D002869:Chromosome Aberrations; D002871:Chromosome Banding; D006224:Cricetinae; D003412:Cricetulus; D004080:Dihydroorotase / Q000235:genetics; D004351:Drug Resistance; D005784:Gene Amplification; D005796:Genes; D009097:Multienzyme Complexes / Q000235:genetics*; D009363:Neoplasm Proteins / Q000235:genetics*; D010746:Phosphonoacetic Acid / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: C033626:CAD trifunctional enzyme; D009097:Multienzyme Complexes; D009363:Neoplasm Proteins; D001224:Aspartic Acid; C013195:sparfosic acid; D001221:Aspartate Carbamoyltransferase; D004080:Dihydroorotase; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing); D010746:Phosphonoacetic Acid