PLX112050

GSE124582: Bromodomain inhibition of the co-activators CBP/EP300 facilitates reprogramming (RNA-seq fibroblasts)

• Organsim human
• Type RNASEQ
• Target gene
• Project ARCHS4

Silencing of the somatic cell-type specific gene expression programs is a critical yet poorly understood step in nuclear reprogramming. To uncover chromatin-related pathways important for maintaining cell identity, we carried out a reprogramming screen using inhibitors of chromatin factors. Here we identify two independent acetyl-lysine competitive inhibitors targeting the bromodomains of coactivators EP300 and CBP as potent enhancers of reprogramming. EP300/CBP bromodomain inhibition is critical during early stages of reprogramming, significantly accelerates the emergence of iPSCs and, when combined with Dot1L inhibition, enables efficient derivation of human iPSCs with Oct4 and Sox2 alone. In contrast, complete inhibition of catalytic acetyl-transferase activity of EP300/CBP prevents reprogramming. Genome-wide expression analyses indicate that EP300/CBP bromodomain inhibition diminishes the expression of somatic-specific genes without affecting the induction of pluripotency regulators. Through expression analyses, we identify the master mesenchymal transcription factor PRRX1 as a functionally important target in reprogramming that is downregulated upon EP300/CBP bromodomain inhibition. Collectively, our data uncover a role for bromodomain-mediated interactions of EP300/CBP in sustaining cell type specific gene expression programs and maintaining somatic cell identity SOURCE: Adam Cribbs (adam.cribbs@imm.ox.ac.uk) - University of Oxford