COUP-TFII is a modulator of cell-type-specific genetic programs based on genomic localization maps

Area of Science:

• Molecular Biology
• Genomics
• Cancer Research

Background:

• Chicken ovalbumin upstream promoter transcription factor II (COUP-TFII) is a nuclear receptor with an unidentified ligand.
• The role of COUP-TFII in cancer cells remains largely unknown.
• Understanding COUP-TFII's function is crucial for cancer biology.

Purpose of the Study:

• To map the cistrome (genomic binding sites) of COUP-TFII in breast, leukemia, and liver cancer cells.
• To identify master transcription factors (TFs) that co-localize with COUP-TFII.
• To characterize the chromatin environment of COUP-TFII binding sites.

Main Methods:

• Utilized publicly available ChIP-seq data to map COUP-TFII binding sites.
• Analyzed co-localization of COUP-TFII with master TFs (ERα, HNF4α, GATA) and CTCF.
• Investigated histone modifications (H3K27ac, H3K4me1, H3K4me3) at identified binding sites.

Main Results:

• COUP-TFII co-localizes with cell-specific master TFs (ERα, HNF4α, GATA) and CTCF.
• COUP-TFII and master TF sites are enriched for active enhancer marks (H3K27ac, H3K4me1).
• COUP-TFII and CTCF sites show active promoter marks (H3K27ac, H3K4me3).
• The VEGFA gene, regulated by shared COUP-TFII/CTCF sites, exhibits cell-type-independent long-range looping.

Conclusions:

• COUP-TFII plays a cell-type-specific role in transcriptional programs.
• COUP-TFII contributes to angiogenesis through VEGFA regulation.
• This study provides genomic insights into COUP-TFII's function in cancer.