Regulation of expression of liver-specific enzymes. III. Further analysis of a series of rat hepatoma X human somatic cell hybrids.
1. The expression of twelve liver-specific enzymes was analysed in twenty-one independent rat hepatoma X human somatic cell hybrids, and in some cases up to forty-one subclones were also tested. 2. Seventeen hybrids continued to express most of the rat liver-specific enzymes and in some cases human isozymes of glutamate-pyruvate transaminase, alpha-glycerophosphate dehydrogenase, guanine deaminase, alcohol dehydrogenase and pyruvate kinase were clearly identified. 3. Analysis of the segregation of the human liver-specific enzymes in these hybrids led to the assignment of human GPT to chromosome 8 (previously reported, Kielty, Povey & Hopkinson, 1982) and suggests the assignment of human GPD1 to chromosome 12. 4. The expression of the various liver-specific enzymes in these hybrids appeared to be controlled by independent regulatory mechanisms. 5. Four unusual reverse segregant hybrids were also analysed, and in these no liver-specific enzyme activity was demonstrable.
D000429:Alcohol Oxidoreductases / Q000235:genetics; D000445:Aldehyde Oxidoreductases / Q000235:genetics; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000201:enzymology; D002874:Chromosome Mapping; D004586:Electrophoresis; D005786:Gene Expression Regulation; D005796:Genes; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics; D006148:Guanine Deaminase / Q000235:genetics; D006801:Humans; D006822:Hybrid Cells / Q000201:enzymology*; D007527:Isoenzymes / Q000235:genetics; D008099:Liver / Q000201:enzymology*; D008113:Liver Neoplasms; D011770:Pyruvate Kinase / Q000235:genetics; D051381:Rats
D007527:Isoenzymes; D000429:Alcohol Oxidoreductases; D005993:Glycerolphosphate Dehydrogenase; D000445:Aldehyde Oxidoreductases; D011770:Pyruvate Kinase; D006148:Guanine Deaminase