CTCF Polyclonal Antibody

Highly conserved transcription factors CTCF (CCCTC-binding factor) and its paralog (BORIS) regulate transcriptional activation and repression, insulator function, and imprinting control regions (ICRs). Both CTCF and BORIS contain 11 conserved zinc finger domains that work together to bind the same DNA elements, even though they have different amino and carboxy termini. CTCF is ubiquitously expressed and influences transcriptional regulation of cell-growth regulated genes. It is also necessary for the enhancer-blocking activity of all known insulator elements and ICRs. CTCF DNA-binding is sensitive to DNA methylation, a mark that determines parent-of-origin selection of the imprinted allele. CTCF functions depend on interactions with various proteins and posttranslational modifications, such as phosphorylation, SUMOylation and poly(ADP-ribosyl)ation. In particular, poly(ADP-ribosyl)ation has been found to regulate CTCF insulator and chromatin barrier functions and may also affects the transcription of rRNA. Mutations in this gene have been associated with aggressive breast cancers, prostate cancers, and Wilms' tumors.