Metabolic cooperation between argininosuccinate synthetase and argininosuccinate lyase deficient human fibroblasts.
Human fibroblasts deficient in either argininosuccinate synthetase or argininosuccinate lyase show low levels of incorporation of [14C]citrulline into protein. However, when these two cell types are co-cultured [14C]citrulline incorporation is restored to the levels found in control cultures. This metabolic cooperation is cell-density-dependent and does not occur by diffusion of argininosuccinate into the medium. Our results indicate that argininosuccinate passes between the two cell types via intercellular junctions, and this system provides a simple and accurately quantifiable model for the study of intercellular communication.
D001120:Arginine / Q000031:analogs & derivatives*; D001124:Argininosuccinate Synthase / Q000172:deficiency; D001125:Argininosuccinic Acid / Q000378:metabolism*; D056807:Argininosuccinic Aciduria; D002450:Cell Communication; D002452:Cell Count; D002460:Cell Line; D002956:Citrulline / Q000378:metabolism*; D003470:Culture Media; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D007365:Intercellular Junctions / Q000378:metabolism; D007700:Kinetics; D007930:Leucine / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism; D009154:Mutation; D014176:Protein Biosynthesis
D003470:Culture Media; D001125:Argininosuccinic Acid; D002956:Citrulline; D001120:Arginine; D001124:Argininosuccinate Synthase; D007930:Leucine