The “Dispensable” Portion of RAG2 Is Necessary for Efficient V-to-DJ Rearrangement during B and T Cell Development

• Published in: Immunity (Cambridge, Mass.) Vol. 17; no. 5; pp. 639 - 651
• Main Authors: Liang, Hong-Erh, Hsu, Lih-Yun, Cado, Dragana, Cowell, Lindsay G., Kelsoe, Garnett, Schlissel, Mark S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-11-2002; Elsevier Limited
• Subjects: Animals; B-Lymphocytes - immunology; Cell Differentiation - genetics; Cell Differentiation - immunology; Cell Line; Cloning; Deoxyribonucleic acid; DNA; DNA Nucleotidyltransferases - immunology; DNA-Binding Proteins - genetics; DNA-Binding Proteins - immunology; Gene Rearrangement, B-Lymphocyte, Heavy Chain - immunology; Gene Rearrangement, beta-Chain T-Cell Antigen Receptor - immunology; Genes; Mice; Mutation; Proteins; Recombination, Genetic - immunology; T cell receptors; T-Lymphocytes - immunology; VDJ Recombinases
• ISSN: 1074-7613; 1097-4180
• DOI: 10.1016/S1074-7613(02)00448-X

Previous in vitro studies defined the minimal regions of RAG1 and RAG2 essential for V(D)J recombination. In order to characterize the role of the C-terminal “dispensable” portion of RAG2, we generated core-RAG2 knock-in mice. We found that the core-RAG2-containing recombinase complex is selectively defective in catalyzing V-to-DJ rearrangement at the IgH and TCRβ loci, resulting in partial developmental blocks in B and T lymphopoiesis. Analysis of recombination intermediates showed defects at the cleavage phase of the reaction. We also observed a reduction in overall recombinase activity in core-RAG2-expressing thymocytes, leading us to suggest that the interaction of a defective recombinase with RSS sequences unique to VH and Vβ gene segments may underlie the specific V-to-DJ rearrangement defect in core-RAG2 mice.