Structure-specific nuclease activity of RAGs is modulated by sequence, length and phase position of flanking double-stranded DNA.
RAGs (recombination activating genes) are responsible for the generation of antigen receptor diversity through the process of combinatorial joining of different V (variable), D (diversity) and J (joining) gene segments. In addition to its physiological property, wherein RAG functions as a sequence-specific nuclease, it can also act as a structure-specific nuclease leading to genomic instability and cancer. In the present study, we investigate the factors that regulate RAG cleavage on non-B DNA structures. We find that RAG binding and cleavage on heteroduplex DNA is dependent on the length of the double-stranded flanking region. Besides, the immediate flanking double-stranded region regulates RAG activity in a sequence-dependent manner. Interestingly, the cleavage efficiency of RAGs at the heteroduplex region is influenced by the phasing of DNA. Thus, our results suggest that sequence, length and phase positions of the DNA can affect the efficiency of RAG cleavage when it acts as a structure-specific nuclease. These findings provide novel insights on the regulation of the pathological functions of RAGs.
['Kumari|Rupa|R|', 'Raghavan|Sathees C|SC|']
D024506:5' Flanking Region D001483:Base Sequence D001665:Binding Sites D004268:DNA-Binding Proteins D003851:Deoxyribonucleases D016654:Genes, RAG-1 D057809:HEK293 Cells D018398:Homeodomain Proteins D006801:Humans D009687:Nuclear Proteins D009690:Nucleic Acid Conformation D009692:Nucleic Acid Heteroduplexes D011994:Recombinant Proteins D060152:V(D)J Recombination
genomic instability RAG cleavage non-B DNA structure heteroduplex DNA chromosomal translocation double-strand break repair