title: Cyclic AMP induces terminal deoxynucleotidyl transferase in immature B cell leukemia lines.
abstract: Terminal deoxynucleotidyl transferase (Tdt), a unique DNA polymerase found only in lymphoid cells, may be involved in the generation of immunoglobulin-combining site diversity. To study the actual metabolic function of the enzyme, we developed a system in which Tdt expression is induced under defined culture conditions. We found that pharmacologic agents that raise intracellular cyclic AMP levels, such as caffeine, induce a three- to 10-fold increase in enzyme biosynthesis rate and activity. This phenomenon is observed only in pre-B cell lines of human or murine origin.
authors.forename: E J
authors.initials: EJ
authors.lastname: Siden
authors.forename: A
authors.initials: A
authors.lastname: Gifford
authors.forename: D
authors.initials: D
authors.lastname: Baltimore
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000201:enzymology* / Q000276:immunology; D003994:Bucladesine / Q000494:pharmacology; D002110:Caffeine / Q000494:pharmacology; D002460:Cell Line; D000242:Cyclic AMP / Q000502:physiology*; D004253:DNA Nucleotidylexotransferase / Q000096:biosynthesis*; D004254:DNA Nucleotidyltransferases / Q000096:biosynthesis*; D004789:Enzyme Activation / Q000187:drug effects; D005333:Fetus; D006801:Humans; D007075:Immunoglobulin M / Q000096:biosynthesis; D007700:Kinetics; D007938:Leukemia / Q000201:enzymology* / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008113:Liver Neoplasms / Q000201:enzymology / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D007075:Immunoglobulin M; D008070:Lipopolysaccharides; D002110:Caffeine; D003994:Bucladesine; D000242:Cyclic AMP; D004254:DNA Nucleotidyltransferases; D004253:DNA Nucleotidylexotransferase