Further studies on the isozyme patterns of branched-chain amino acid transminase in cultured rat hepatocytes.
Among several lines of cultured rat hepatocytes examined, one line, IAR-22, contained enzyme III as well as enzyme I of the isozymes of branched-chain amino acid transaminase (EC 2.6.1.42) and this cell line was tumorigenic. None of the cell lines tested contained enzyme II (EC 2.6.1.6) or tyrosine transaminase (EC 2.6.1.5) and addition of dexamethasone did not induce these transaminases. The PC-1 line, containing only enzyme I and having a high percentage of diploid cells, showed deviation of its chromosomal number and tumorigenicity, but no change in its isozyme pattern when transformed with N-methyl-N'-nitro-N-nitrosoguanidine. Therefore, judging from expression of isozymes of the transaminase, this transformed cell line retained moderate differentiation.
D000596:Amino Acids; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002875:Chromosomes; D007527:Isoenzymes / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008769:Methylnitronitrosoguanidine; D013997:Time Factors; D000637:Transaminases / Q000378:metabolism*
D000596:Amino Acids; D007527:Isoenzymes; D008769:Methylnitronitrosoguanidine; D000637:Transaminases