Figure. 2. The rs3824662 A allele increases GATA3 expression and induces global expression changes in GM12878 cells and ALL PDX samples.
a, Effects of rs3824662 on gene expression within the local topologically associating domain (TAD). Gene expression was quantified by qPCR in wildtype (C/C) and engineered GM12878 cells (A/A), normalized to ACTB (n=3). TAD was defined using the GM12878 wildtype Hi-C data. Bottom panel shows results of ALL PDX samples (n=2, 3, and 2 for those with AA, AC, and CC genotype). Data are presented as mean values +/− SEM. b, Chromatin interactions between the rs3824662 (yellow bar) and GATA3 promoter (red bar) as determined by Capture-C. c, Heatmap of GATA3 ChIP-seq and ATAC-seq in GM12878 (WT) and engineered GM12878 (A/A) cells. Each row represents a 6kb genomic region flanking a GATA3 binding site that is specific in engineered GM12878 (A/A) cells. d, Luciferase reporter assay showed that rs3824662 enhancer activity increased with co-expression of NFIC, particularly with the enhancer element harboring the A allele (n = 8), two-sided unpaired T test, pGL4.23 rs3824662 A vs. pGL4.23 rs3824662 C, p-value = 0.0003997. e, shRNA-mediated knockdown of NFIC in GM12878 (A/A) cells resulted in significant reduction of GATA3 expression, n = 3 for each bar, two-sided unpaired T test, In the NFIC group, Parental vs. NFIC shRNA1 p-value = 0.002738, Parental vs. NFIC shRNA2 p-value = 0.003499, Parental vs. NFIC shRNA3 p-value = 0.003998. For the GATA3 group, Parental vs. NFIC shRNA1 p-value = 0.004096, Parental vs. NFIC shRNA2 p-value = 0.004434, Parental vs. NFIC shRNA3 p-value = 0.009699. Data are presented as mean values +/− SEM. f, 232 Differential gene expression between GM12878 (A/A) and GM12878 (WT) cell lines were also validated in PDX samples with different genotype at rs3824662. g, Gene Set Enrichment Analysis of genes upregulated with the A allele at 3824662 in the Molecular Signatures Database (MSigDB) shows enrichment of microtubule polymerization. h, Genes up-regulated in the GM12878 (A/A) cell line are showed more significant enrichment of GATA3 binding than those not affected or up-regulated in the GM12878 (WT) cells.