Send to

Choose Destination
Nat Immunol. 2005 Jul;6(7):730-6. Epub 2005 Jun 5.

The MRE11-RAD50-NBS1 complex accelerates somatic hypermutation and gene conversion of immunoglobulin variable regions.

Author information

Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98195-7650, USA.


Targeted diversification of immunoglobulin variable regions is induced by activation-induced deaminase and may occur by either somatic hypermutation or gene conversion. MRE11-RAD50-NBS1 (MRN) is a ubiquitous and conserved nuclease complex critical for DNA break repair and is essential in class-switch recombination. Here we show that ectopic expression of NBS1, the regulatory subunit of MRN, accelerated hypermutation in the human B cell line Ramos and accelerated gene conversion in the chicken B cell line DT40. In both cases, accelerated diversification depended on MRN complex formation. These data suggest that MRN promotes DNA cleavage and/or mutagenic repair of lesions initiated by activation-induced deaminase, acting in the shared pathway of immunoglobulin gene diversification.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center