title: Tumour-specific phenylalanine tRNA contains two supernumerary methylated bases.
abstract: Every malignant tumour examined contains aberrant tRNA methyltransferases and a few tRNAs which are absent from the normal tissue of origin. To determine whether tumour-specific tRNAs have different modifications from those in normal tissue, we purified the most frequently occurring tumour-specific isoaccepting tRNA from two malignant tissues. The isoaccepting phenylalanine tRNA from Novikoff hepatoma and Ehrlich ascites cells both contain two supernumerary methylated bases. One of these l-methylguanine, is absent from the phenylalanine tRNA of normal rat, mouse, rabbit and calf liver. An increase in the levels of 5-methylcytidine and dihydrouridine was also detected.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002286:Carcinoma, Ehrlich Tumor / Q000032:analysis; D006528:Carcinoma, Hepatocellular / Q000032:analysis; D008113:Liver Neoplasms; D008745:Methylation; D051379:Mice; D009374:Neoplasms, Experimental / Q000032:analysis* / Q000201:enzymology; D010649:Phenylalanine; D012334:RNA, Neoplasm / Q000032:analysis*; D012343:RNA, Transfer / Q000032:analysis*; D051381:Rats; D012359:tRNA Methyltransferases / Q000378:metabolism
chemical_list: D012334:RNA, Neoplasm; D010649:Phenylalanine; D012343:RNA, Transfer; D012359:tRNA Methyltransferases