Fig. 5
CRP induces RA-associated chromatin dysregulation via FRA2. a Heatmap showing changes in chromatin accessibility in monocytes stimulated with the presence or absence of CRP for 12 h (p < 0.01 and |fold change| > 1.5). ATAC-seq was used to assess five independent biological replicates. b The upregulated peaks of CRP-stimulation were enriched for transcription factors using HOMER and ranked by p. c Volcano plot showing changes of gene expression in monocytes stimulated with CRP (10 μg/mL) in the presence or absence for 12 h; red dots correspond to upregulated genes with significant (p < 0.05 and |fold change| > 1.5). RNA-seq was performed in three independent biological replicates (monocytes derived from three different patients with OA). d Expression levels of genes FOSL2 were confirmed by real-time RT-PCR in control and CRP stimulation group. The p value was estimated from unpaired Student’s t test. ****p < 0.0001. Error bar represent standard error of the mean (SEM). e Visualization of ATAC-seq footprint for FRA2 motifs in control and CRP stimulation. The ATAC-seq signal across all the motif binding sites in the genome were aligned on the motif and averaged. f Barplot shows expression level of genes with containing FRA2 binding sites during control and CRP stimulation. Error bar represent standard error of the mean (SEM). The p value was estimated from unpaired Student’s t test. ****p < 0.0001. g, h Normalized ATAC-seq profiles at the OCSTAMP(g) and IL-1B(h) locus in control and CRPstim. The shaded regions are more accessible representative peaks containing the FRA2 binding site after CRP stimulation. i, j Expression levels of genes OCSTAMP (i) and IL-1B (j) were confirmed by real-time RT-PCR in control and CRP stimulation group. Error bar represent standard error of the mean (SEM). The p value was estimated from unpaired Student’s t test. *p < 0.05, **p < 0.01. CRP, C-reaction protein; CRPstim, CRP stimulation