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Lineage-specific functions of Bcl6 Â in immunity and inflammation are mediated through distinct biochemical mechanisms

ABSTRACT: The transcription factor Bcl6 orchestrates the germinal center reaction through its actions in B and T cells, and regulates inflammatory signaling in macrophages. We report that genetic replacement by mutant Bcl6, which cannot bind corepressors to its BTB domain, disrupted Â germinal center formation and immunoglobulin affinity maturation, due to a defect in B cell Â proliferation and survival. In contrast, BTB loss of function had no effect on T follicular helper cell differentiation and function, nor other T helper subsets. Bcl6 null mice displayed a lethal inflammatory phenotype, whereas BTB mutant mice experienced normal healthy lives with no inflammation. Bcl6 repression of inflammatory responses in macrophages was accordingly independent of the BTB domain repressor function. Bcl6 thus mediates its actions through lineage-specific biochemical functions. ChIP-seq for Bcl6, SMRT and BCOR in germinal center B cells

ORGANISM(S): Homo sapiens

SUBMITTER: Katerina Hatzi

PROVIDER: E-GEOD-43350 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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