Three-dimensional clustering of human RAG2 gene mutations in severe combined immune deficiency.
The V(D)J recombination, which leads to the somatic rearrangement of variable, diversity, and joining segments, is the mechanism accountable for the diversity of T cell receptor- and Ig-encoding genes. The products of the RAG1 and RAG2 genes are the lymphoid-specific factors responsible for the initiation of the V(D)J recombination through the generation of a DNA double strand break. RAG1 or RAG2 gene inactivation in the mouse leads to abortion of the V(D)J rearrangement process, early block in both T and B cell maturation, and, ultimately, to severe combined immune deficiency (SCID). A human SCID condition is also characterized by an absence of mature T and B lymphocytes and is associated with mutations in either RAG1- or RAG2-encoding genes. Based on the predicted beta-propeller three-dimensional structure model for RAG2, we found that six out of the seven mutations described to date in T-B-SCID patients are clustered on one side of the propeller, in regions exposed to solvent. This finding reinforces the biological significance of this predicted model and suggests that RAG1 interacts with RAG2 on one of the side of the scaffold formed by the beta-propeller.
Corneo
B
B
Développement Normal et Pathologique du Système Immunitaire, INSERM U429, Hôpital Necker Enfants Malades, Paris 75015, France.
Moshous
D
D
Callebaut
I
I
de Chasseval
R
R
Fischer
A
A
de Villartay
J P
JP
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002461:Cell Line, Transformed; D003001:Cloning, Molecular; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D005347:Fibroblasts / Q000378:metabolism; D016654:Genes, RAG-1 / Q000235:genetics; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000737:chemistry; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation; D009687:Nuclear Proteins; D010641:Phenotype; D017434:Protein Structure, Tertiary; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D016511:Severe Combined Immunodeficiency / Q000235:genetics*; D045567:VDJ Recombinases
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; C499311:RAG2 protein, human; C064655:V(D)J recombination activating protein 2; C064658:RAG-1 protein; D004254:DNA Nucleotidyltransferases; D045567:VDJ Recombinases