Identification of two catalytic residues in RAG1 that define a single active site within the RAG1/RAG2 protein complex.
During V(D)J recombination, the RAG1 and RAG2 proteins cooperate to catalyze a series of DNA bond breakage and strand transfer reactions. The structure, location, and number of active sites involved in RAG-mediated catalysis have as yet not been determined. Using protein secondary structure prediction algorithms, we have identified a region of RAG1 with possible structural similarities to the active site regions of transposases and retroviral integrases. Based on this information, we have identified two aspartic acid residues in RAG1 (D600 and D708) that function specifically in catalysis. The results support a model in which RAG1 contains a single, divalent metal ion binding active site structurally related to the active sites of transposases/integrases and responsible for all catalytic functions of the RAG protein complex.
Fugmann
S D
SD
Howard Hughes Medical Institute, Section of Immunobiology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Villey
I J
IJ
Ptaszek
L M
LM
Schatz
D G
DG
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001224:Aspartic Acid; D001665:Binding Sites; D020134:Catalytic Domain; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity; D019895:Transposases / Q000737:chemistry / Q000378:metabolism; D045567:VDJ Recombinases
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; C499308:Rag2 protein, mouse; D011994:Recombinant Proteins; C064655:V(D)J recombination activating protein 2; C064658:RAG-1 protein; D001224:Aspartic Acid; D004247:DNA; D004254:DNA Nucleotidyltransferases; D019895:Transposases; D045567:VDJ Recombinases