BioProject

The transcription factor (TF) Forkhead Box P3 (FOXP3) is constitutively expressed in high levels in natural occurring CD4+CD25+ regulatory T cells (nTreg) and is not only the most accepted marker for that cell population, but is considered lineage determinative. More...

The transcription factor (TF) Forkhead Box P3 (FOXP3) is constitutively expressed in high levels in natural occurring CD4+CD25+ regulatory T cells (nTreg) and is not only the most accepted marker for that cell population, but is considered lineage determinative. Chromatin immunoprecipitation (ChIP) of transcription factors in combination with genomic tiling microarray analysis (ChIP-on-Chip) has been shown to be an appropriate tool to identify FOXP3 transcription factor binding sites (TFBS) on a genome-wide scale. In combination with microarray expression analysis the ChIP-on-Chip technique allows to identify direct FOXP3 target genes. ChIP-on-Chip analysis of human FOXP3Δ2 isoform expressed in resting and PMA / ionomycin stimulated Jurkat T cells revealed several thousand putative FOXP3 binding sites and importance of intronic regions for FOXP3 binding. Knowledge of general distribution patterns of FOXP3 TFBS in the human genome under resting and activated conditions contributes to a better understanding of this TF and its influence on direct target genes with importance for Treg cell phenotype and function. Overall design: ChIP-DNA from FOXP3(Δ2) expressing Jurkat T cells under resting and PMA / ionomycin stimulated conditions from duplicate experiments was analyzed. FOXP3-specific tiling array data were analyzed in reference to an individual isotype control dataset (J-FOXP3 ChIP'd with FOXP3 antibody vs. J-FOXP3 ChIP'd with isotype control antibody). In total 8 tiling array analyses were performed (2x resting J-FOXP3 with FOXP3-IP, 2x resting J-FOXP3 with isotype-IP, 2x PMA/iono J-FOXP3 with FOXP3-IP, 2x PMA/iono J-FOXP3 with isotype-IP) Less...