Send to

Choose Destination
J Biol Chem. 2010 Mar 26;285(13):9327-38. doi: 10.1074/jbc.M109.098251. Epub 2010 Jan 25.

The mouse immunoglobulin heavy chain V-D intergenic sequence contains insulators that may regulate ordered V(D)J recombination.

Author information

Laboratory of Chromatin and Gene Expression, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom.


During immunoglobulin heavy chain (Igh) V(D)J recombination, D to J precedes V to DJ recombination in an ordered manner, controlled by differential chromatin accessibility of the V and DJ regions and essential for correct antibody assembly. However, with the exception of the intronic enhancer Emu, which regulates D to J recombination, cis-acting regulatory elements have not been identified. We have assembled the sequence of a strategically located 96-kb V-D intergenic region in the mouse Igh and analyzed its activity during lymphocyte development. We show that Emu-dependent D antisense transcription, proposed to open chromatin before D to J recombination, extends into the V-D region for more than 30 kb in B cells before, during, and after V(D)J recombination and in T cells but terminates 40 kb from the first V gene. Thus, subsequent V antisense transcription before V to DJ recombination is actively prevented and must be independently activated. To find cis-acting elements that regulate this differential chromatin opening, we identified six DNase I-hypersensitive sites (HSs) in the V-D region. One conserved HS upstream of the first D gene locally regulates D genes. Two further conserved HSs near the D region mark a sharp decrease in antisense transcription, and both HSs bind CTCF in vivo. Further, they both possess enhancer-blocking activity in vivo. Thus, we propose that they are enhancer-blocking insulators preventing Emu-dependent chromatin opening extending into the V region. Thus, they are the first elements identified that may control ordered V(D)J recombination and correct assembly of antibody genes.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center