Heterarchy of Transcription Factors Driving Basal and Luminal Cell Phenotypes in Human Urothelium

摘要: Cell differentiation is affected by complex networks of transcription factors that co-ordinate re-organisation the chromatin landscape. The hierarchies these relationships can be difficult to dissect. During in vitro normal human uro-epithelial cells, formaldehyde-assisted isolation regulatory elements (FAIRE-seq) and RNA-seq was used identify alterations accessibility gene expression changes following activation nuclear receptor peroxisome proliferator-activated gamma (PPARγ) as a differentiation-initiating event. Regions identified FAIRE-seq, having altered during differentiation, were found enriched with sequence-specific binding motifs for predicted involved driving basal differentiated urothelial cell phenotypes, including forkhead box A1 (FOXA1), P63, GRHL2, CTCF GATA-binding protein 3 (GATA3). In addition, co-occurrence GATA3 observed within subsets differentiation-specific peaks containing P63 or FOXA1. Changes abundance immunoblots chromatin-enriched extracts. Transient siRNA knockdown revealed favoured basal-like phenotype inhibiting promoting marker genes. prevented differentiation-associated downregulation transcript, demonstrated positive feedback on PPARG but showed no effect FOXA1 transcript expression. This approach indicates transcriptionally regulated programme, operates heterarchy, wherein able co-operate drive luminal genes, has potential transrepress same