Figure 2.

Stiff matrix promotes DNA demethylation in a conserved 5′ regulatory region in human and mouse DSP/Dsp (desmoplakin) genes. (A) Schematic diagram of human, mouse, and rat DSP/Dsp genes. The conserved 560-bp DNA sequences (78% homology) are indicated by ovals. Columns represent DSP/Dsp exons. (B) Analysis of CpG dinucleotides in a 30+-kb region, including the 20-kb 5′ regulatory region, exon 1, and intron 1. CpG-rich regions are indicated by areas marked with diagonals. (C) DNA methylation profiling analysis for the 560-bp conserved region in human alveolar epithelial adenocarcinoma cells and mouse primary type II alveolar epithelial cells cultured on soft and stiff matrix. Ten clones were sequenced for each condition. Solid circles indicate methylated CpG islands. Open circles indicate unmethylated CpG islands. Results are mean ± SD of three independent experiments. *P < 0.05; **P < 0.01. AP-2 = activator protein-2; C/EBPβ = CCAAT/enhancer-binding protein β; dist = distal; EGR1 = early growth response protein 1; ETF = EGFR [epidermal growth factor receptor]-specific transcription factor; prox = proximal.