title: Influence on certain amino acids on steps leading to DNA synthesis in concanavalin A-treated guinea-pig lymphocytes.
abstract: When guinea-pig lymph node cells were exposed to ConA in a culture medium lacking glutamine or cysteine, no DNA synthesis occurred. The addition of the missing acid to ConA-treated lymphocytes submitted to glutamine or cysteine starvation for 40 h allowed the synthesis of DNA to take place after a period of only 10-12 h. The synthesis of DNA is preceded by a rapid increase of 3H-uridine incorporation into RNA and of 3H-leucine incorporation into protein which occurred a few hours after addition of the missing amino acid. When cycloheximide was added to lymphocytes exposed to ConA in a glutamine or cysteine deprived medium, a relative enhancement of uridine incorporation was observed. No such effect was provoked by puromycin. These results suggest the possibility of a control system in lymphocytes similar to those described in microbial cells for amino acid control of RNA synthesis.
mesh_terms: D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D003545:Cysteine / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects*; D005973:Glutamine / Q000494:pharmacology; D006168:Guinea Pigs; D008213:Lymphocyte Activation / Q000187:drug effects*; D008214:Lymphocytes / Q000378:metabolism*; D014176:Protein Biosynthesis; D011691:Puromycin / Q000494:pharmacology; D012313:RNA / Q000096:biosynthesis*
chemical_list: D000596:Amino Acids; D005973:Glutamine; D003208:Concanavalin A; D011691:Puromycin; D012313:RNA; D003513:Cycloheximide; D003545:Cysteine