Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.7 (adenine phosphoribosyltransferase)
 692 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Somatic cell hybridization techniques were applied to gene linkage analysis in the laboratory mouse. Cells of an established line of Chinese hamster lung fibroblasts were fused with mouse embryo fibroblasts and with mouse peritoneal macrophages obtained from different inbred strains. From 3 hybridization experiments, 123 primary and secondary clones were isolated in HAT selective medium and 24 were back-selected in 8-azaguanine. Hybrid clones were characterized for the expression of 16 murine isozymes by starch, acrylamide, and Cellogel electrophoresis, and on the basis of segregation data, 3 syntenic associations could be made. Malate oxidoreductase decarboxylating (MOD) and mannose phosphate isomerase (MPI) segregated concordantly, confirming an established linkage relationship; adenine phosphoribosyltransferase (APRT) segregated concordantly with glutathione reductase (GR) which is known to be on chromosome 8; alpha-galactosidase was observed to be syntenic with hypoxanthine phosphoribosyltransferase (HPRT), and X-linked enzyme. All other isozymes examined segregated independently of one another.
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PMID:Gene linkage analysis in the mouse by somatic cell hybridization: assignment of adenine phosphoribosyltransferase to chromosome 8 and alpha-galactosidase to the X chromosome. 123 12

Transfection of mammalian cells with genomic DNA and cloned genes is now relatively routine. However, the vast majority of studies have used rodent cells as recipients. Here we describe efficient transfection of two human cell lines, the hypoxanthine guanine phosphoribosyltransferase (HPRT)-deficient HeLa line, D98/AH-2, and the adenine phosphoribosyltransferase (APRT)-deficient HT1080 line, HTD114. D98/AH-2 cells were transfected with the pSV2-gpt plasmid of Mulligan and Berg, which contains the E. coli xanthine-guanine phosphoribosyltransferase (gpt) gene, and Gpt + transfectants were selected in HAT medium. HTD114 cells were transfected with (1) genomic hamster DNA, and ouabain resistant transfectants were selected in 5 X 10(-7)M ouabain; (2) with hamster and mouse genomic DNA, and Aprt + cells were selected in AAA medium; (3) with plasmids containing either the cloned hamster or mouse APRT genes, and Aprt + cells were selected; and (4) with phage particles containing a cloned mouse APRT gene, and Aprt + cells were selected. Transfection efficiencies ranged from 0.25 to 1.5 X 10(3) transfectants per microgram DNA, and in certain cases secondary transfections were done. Foreign DNA in recipients was detected by blot hybridization, and the expression of foreign genes was detected by cell growth in selective media and the expression of enzymes characteristic of the species of the donor DNA. The majority of transfectants showed stable expression of the transgenome.
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PMID:Plasmid, phage, and genomic DNA-mediated transfer and expression of prokaryotic and eukaryotic genes in cultured human cells. 623 89

Chinese hamster ovary (CHO) cell lines heterozygous at both the adenine phosphoribosyltransferase (aprt) and thymidine kinase (tk) loci were used for single-step selection of spontaneous and induced mutants resistant to 8-azaadenine (AAr), 6-thioguanine (TGr), ouabain (OUAR), or 5-fluorodeoxyuridine (FUdRr). Mutation data are reported for direct mutagens (EMS, ethyl methanesulfonate; MNNG, N-methyl-N'-nitro-N-nitrosoguanidine; NQO, 4-nitroquinoline 1-oxide) and promutagens (DMN, dimethylnitrosamine; BP, benzo[a]-pyrene) activated by rat-liver homogenates. Optimal plating densities were established for AAr, TGr, OUAR and FUdRr. The induced mutant frequencies as a function of relative cell survival after treatment with EMS, DMN or BP were 2--4 d for AAr, 6--8 d for TGr, 3 d for OUAR, and 1--3 d for FUdRr. The induced mutant frequencies as a function of relative cell survival after treatment with EMS, DMN or BP showed locus-specific differences in sensitivity. Of 61 clonal isolates resistant to AA and assayed for APRT activity, 87% had less than or equal to 5% wild-type activity; of 30 TGr clones assayed, 83% had less than or equal to 5% wild-type HGPRT activity. Of 42 FUdRr clones assayed, 98% had less than or equal to 1% wild-type TK activity. 50 clones selected in medium containing FUdR displayed cross-resistance to 5-bromodeoxyuridine (BUdR) and trifluorothymidine (TFT) and all were sensitive to HAT (hypoxanthine--amethopterin--thymidine) medium. The tk locus showed the largest mutational response as a function of cell survival after mutagen treatment. The rapid expression kinetics for FUdRr and the possibility that the locus detects a broader spectrum of genetic lesions than the other drug-resistance markers are discussed in terms of a sensitive screening assay for detecting potential mutagens.
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PMID:Mutagenicity testing in mammalian cells. II. Validation of multiple drug-resistance markers having practical application for screening potential mutagens. 644 64