The zinc finger transcription factor ZXDC activates CCL2 gene expression by opposing BCL6-mediated repression
MOLECULAR IMMUNOLOGY
Authors: Ramsey, Jon E.; Fontes, Joseph D.
Abstract
The zinc finger X-linked duplicated (ZXD) family of transcription factors has been implicated in regulating transcription of major histocompatibility complex class II genes in antigen presenting cells; roles beyond this function are not yet known. The expression of one gene in this family, ZXD family zinc finger C (ZXDC), is enriched in myeloid lineages and therefore we hypothesized that ZXDC may regulate myeloid-specific gene expression. Here we demonstrate that ZXDC regulates genes involved in myeloid cell differentiation and inflammation. Overexpression of the larger isoform of ZXDC, ZXDC1, activates expression of monocyte-specific markers of differentiation and synergizes with phorbol 12-myristate 13-acetate (which causes differentiation) in the human leukemic monoblast cell line U937. To identify additional gene targets of ZXDC1, we performed gene expression profiling which revealed multiple inflammatory gene clusters regulated by ZXDC1. Using a combination of approaches we show that ZXDC1 activates transcription of a gene within one of the regulated clusters, chemokine (C-C motif) ligand 2 (CCL2; monocyte chemoattractant protein 1; MCP1) via a previously defined distal regulatory element. Further, ZXDC1-dependent up-regulation of the gene involves eviction of the transcriptional repressor B-cell CLL/Iymphoma 6 (BCL6), a factor known to be important in resolving inflammatory responses, from this region of the promoter. Collectively, our data show that ZXDC1 is a regulator in the process of myeloid function and that ZXDC1 is responsible for Ccl2 gene de-repression by BCL6. (C) 2013 Elsevier Ltd. All rights reserved.
An eQTL variant of ZXDC is associated with IFN-gamma production following Mycobacterium tuberculosis antigen-specific stimulation
SCIENTIFIC REPORTS
Authors: Jabot-Hanin, Fabienne; Cobat, Aurelie; Feinberg, Jacqueline; Orlova, Marianna; Niay, Jonathan; Deswarte, Caroline; Poirier, Christine; Theodorou, Ioannis; Bustamante, Jacinta; Boisson-Dupuis, Stephanie; Casanova, Jean-Laurent; Alcais, Alexandre; Hoal, Eileen G.; Delacourt, Christophe; Schurr, Erwin; Abel, Laurent
Abstract
There is a large inter-individual variability in the response to Mycobacterium tuberculosis infection. In previous linkage analyses, we identified a major locus on chromosome region 8q controlling IFN-gamma production after stimulation with live BCG (Bacillus Calmette-Guerin), and a second locus on chromosome region 3q affecting IFN-gamma production triggered by the 6-kDa early secretory antigen target (ESAT-6), taking into account the IFN-gamma production induced by BCG (IFN gamma-ESAT6(BCG)). High-density genotyping and imputation identified similar to 100,000 variants within each linkage region, which we tested for association with the corresponding IFN-gamma phenotype in families from a tuberculosis household contact study in France. Significant associations were replicated in a South African familial sample. The most convincing association observed was that between the IFN gamma-ESAT6(BCG) phenotype and rs9828868 on chromosome 3q (p = 9.8 x 10(-6) in the French sample). This variant made a significant contribution to the linkage signal (p < 0.001), and a trend towards the same association was observed in the South African sample. This variant was reported to be an eQTL of the ZXDC gene, biologically linked to monocyte IL-12 production through CCL2/MCP1. The identification of rs9828868 as a genetic driver of IFN gamma production in response to mycobacterial antigens provides new insights into human anti-tuberculosis immunity.