Increased frequency of aberrant V(D)J recombination products in core RAG-expressing mice.
RAG1 and RAG2 play a central role in V(D)J recombination, a process for antigen receptor gene assembly. The truncated 'core' regions of RAGs are sufficient to catalyze the recombination reaction, although with lower joining efficiency than full-length proteins. To investigate the role of the non-core regions of RAGs in the end-joining phase of antigen receptor rearrangement, we analyzed recombination products isolated from core RAG1 and core RAG2 knock-in mice. Here, we report that the truncation of RAGs increases the frequency of aberrant recombination in vivo. Signal joints (SJs) associated with V-to-D recombination of core RAG1 knock-in mice were normal, whereas those of core RAG2 knock-in mice were highly imprecise, containing large deletions and additions, and in some cases coding sequences. In contrast, we found an elevated level of imprecise D-to-J associated SJs for both core RAG1- and RAG2-expressing mice. Likewise, sequences of coding joints (CJs) were also affected by the expression of core RAGs. Finally, sequences found at the junctions of rearranged T-cell receptor loci were highly influenced by differences in rearranging recombination signal sequence pairs. We provide the first evidence that the non-core regions of RAGs have critical functions in the proper assembly and resolution of recombination intermediates in endogenous antigen receptor loci.
Talukder
Sadiqur R
SR
Institute for Genome Research, University of Tokushima, Tokushima 770-8503, Japan and Howard Hughes Medical Institute, Children's Hospital, Harvard Medical School, CBR Institute for Biomedical Research, Boston, MA 02115, USA.
Dudley
Darryll D
DD
Alt
Frederick W
FW
Takahama
Yousuke
Y
Akamatsu
Yoshiko
Y
D000818:Animals; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015321:Gene Rearrangement; D018390:Gene Targeting; D016654:Genes, RAG-1; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000378:metabolism; D007128:Immunoglobulin Fragments / Q000235:genetics*; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D011946:Receptors, Antigen / Q000235:genetics*; D017384:Sequence Deletion
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D007128:Immunoglobulin Fragments; D007133:Immunoglobulin Joining Region; D007135:Immunoglobulin Variable Region; C499308:Rag2 protein, mouse; D011946:Receptors, Antigen; C064655:V(D)J recombination activating protein 2; C064658:RAG-1 protein