title: Rag-1: a topoisomerase?
abstract: Recombination activating genes Rag-1 and Rag-2 were isolated on the basis of their ability to confer V(D)J recombination activity when co-expressed in fibroblasts. The mode of action of the confer V(D)J recombination activity when co-expressed in fibroblasts. The mode of action of the products of these genes is not known. Based on sequence comparison data, it was suggested that Rag-1 protein could act like a topoisomerase and that tyrosine in position 998 could be the active site tyrosine. We tested this hypothesis by introducing a point mutation on the Rag-1 cDNA, transforming the tyrosine codon into a phenylalanine codon. We show that the mutation has no effect on site specific recombination implying that Tyr-998 is not essential for the recombination reaction.
authors.affiliation: Unité de Génétique et Biochimie du Développement, CNRS URA 361, Institut Pasteur, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Kallenbach
authors.forename: T
authors.initials: T
authors.lastname: Brinkmann
authors.forename: F
authors.initials: F
authors.lastname: Rougeon
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004254:DNA Nucleotidyltransferases; D004268:DNA-Binding Proteins / Q000235:genetics*; D018398:Homeodomain Proteins; D051379:Mice; D008969:Molecular Sequence Data; D011506:Proteins / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014443:Tyrosine; D045567:VDJ Recombinases
chemical_list: D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D011506:Proteins; D011993:Recombinant Fusion Proteins; C064658:RAG-1 protein; D014443:Tyrosine; D004254:DNA Nucleotidyltransferases; D045567:VDJ Recombinases