| First Author | Kuo TC | Year | 2004 |
| Journal | J Immunol | Volume | 173 |
| Issue | 9 | Pages | 5556-63 |
| PubMed ID | 15494505 | Mgi Jnum | J:93748 |
| Mgi Id | MGI:3505644 | Doi | 10.4049/jimmunol.173.9.5556 |
| Citation | Kuo TC, et al. (2004) B lymphocyte-induced maturation protein (Blimp)-1, IFN regulatory factor (IRF)-1, and IRF-2 can bind to the same regulatory sites. J Immunol 173(9):5556-63 |
| abstractText | The transcriptional repressor B lymphocyte-induced maturation protein-1 (Blimp-1) is expressed in some differentiated cells and is required for terminal differentiation of B cells. To facilitate identification of Blimp-1 target genes, we have determined the optimal DNA recognition sequence for Blimp-1. The consensus is very similar to a subset of sites recognized by IFN regulatory factors (IRFs) that contain the sequence GAAAG. By binding competition and determination of equilibrium dissociation constants, we show that Blimp-1, IRF-1, and IRF-2 have similar binding affinities for functionally important regulatory sites containing this sequence. However, Blimp-1 does not bind to all IRF sites, and specifically does not recognize IRF-4/PU.1 or IRF-8 sites lacking the GAAAG sequence. Chromatin immunoprecipitation studies showed that Blimp-1, IRF-1, and IRF-2 all bind the IFN-beta promoter in vivo, as predicted by the in vitro binding parameters, and in cotransfections Blimp-1 inhibits IRF-1-dependent activation of the IFN-beta promoter. Thus, our data suggest that Blimp-1 competes in vivo with a subset of IRF proteins and help predict the sites and IRF family members that may be affected. |
