B-Cell CLL/Lymphoma 6B (Bcl6B)

Bazf, the deduced 474-amino acid protein contains an N-terminal POZ domain and 5 C-terminal zinc finger motifs. Bazf shares significant similarity in domain structure and amino acid sequence with BCL6, including complete conservation of a 17-amino acid sequence in the middle portion of the proteins. Northern blot analysis detected a 3.8-kb transcript in mouse heart and lung, and RT-PCR detected expression in all tissues examined. Bazf colocalized with Bcl6 within the nucleus of transfected mouse fibroblasts.The repressor activity was associated with both the POZ domain and the middle portion of Bazf. The 17-amino acid conserved region was critical for repressor activity. Expression of Bazf was induced in activated lymphocytes as an immediate-early gene.