| First Author | Liu Z | Year | 2006 |
| Journal | Immunity | Volume | 24 |
| Issue | 4 | Pages | 405-15 |
| PubMed ID | 16618599 | Mgi Jnum | J:113347 |
| Mgi Id | MGI:3665501 | Doi | 10.1016/j.immuni.2006.02.001 |
| Citation | Liu Z, et al. (2006) A recombination silencer that specifies heterochromatin positioning and ikaros association in the immunoglobulin kappa locus. Immunity 24(4):405-15 |
| abstractText | Allelic exclusion ensures that individual B lymphocytes produce only one kind of antibody molecule. Previous studies have shown that allelic exclusion of the mouse Igkappa locus occurs by the combination of monoallelic silencing and a low level of monoallelic activation for rearrangement combined with a negative feedback loop blocking additional functional rearrangements. Using yeast artificial chromosome-based single-copy isotransgenic mice, we have identified a cis-acting element that negatively regulates rearrangement in this locus, specifically in B cells. The element, termed Sis, resides in the V-J intervening sequence. Sis specifies the targeting of Igkappa transgenes in pre-B and B cells to centromeric heterochromatin and associates with Ikaros, a repressor protein that also colocalizes with centromeric heterochromatin. Significantly, these are hallmarks of silenced endogenous germline Igkappa genes in B cells. These results lead us to propose that Sis participates in the monoallelic silencing aspect of allelic exclusion regulation. |
