CST, 2899S, CTCF Antibody

Polyclonal Antibody for studying CTCF. Validated for WB,IP,IF,ChIP. Highly specific and rigorously validated in-house, CTCF Antibody (CST #2899) is ready to ship. Product Usage Information For optimal ChIP results, use 20 μl of antibody and 10 μg of chromatin (approximately 4 x 10 6 cells) per IP. This antibody has been validated using SimpleChIP ® Enzymatic Chromatin IP Kits. Western Blotting: 1:1000 Immunoprecipitation: 1:50 Immunofluorescence (Immunocytochemistry): 1:100 - 1:400 Chromatin IP: 1:25 Storage Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at -20°C. Do not aliquot the antibody. Protocol Available protocols: Western Blotting, Immunoprecipitation, Immunofluorescence (Immunocytochemistry), Chromatin IP Specificity / Sensitivity CTCF Antibody detects endogenous levels of total CTCF protein. This antibody does not cross-react with BORIS. Species Reactivity: Human, Mouse, Rat, Monkey Source / Purification Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the carboxy terminus of the human CTCF protein. Antibodies are purified by protein A and peptide affinity chromatography. Background CCCTC-binding factor (CTCF) and its paralog, the Brother of the Regulator of Imprinted Sites (BORIS), are highly conserved transcription factors that regulate transcriptional activation and repression, insulator function, and imprinting control regions (ICRs) (1-4). Although they have divergent amino and carboxy termini, both proteins contain 11 conserved zinc finger domains that work in combination to bind the same DNA elements (1). CTCF is ubiquitously expressed and contributes to transcriptional regulation of cell-growth regulated genes, including , , , , , , , and (1). CTCF also binds to and is required for the enhancer-blocking activity of all known insulator elements and ICRs, including the H19/IgF2, Prader-Willi/Angelman syndrome, and Inactive X-Specific Transcript (XIST) anti-sense loci (5-7). CTCF DNA-binding is sensitive to DNA methylation, a mark that determines selection of the imprinted allele (maternal vs. paternal) (1). The various functions of CTCF are regulated by at least two different post-translational modifications. Poly(ADP-ribosyl)ation of CTCF is required for insulator function (8). Phosphorylation of Ser612 by protein kinase CK2 facilitates a switch of CTCF from a transcriptional repressor to an activator at the c-Myc promoter (9). mutations or deletions have been found in many breast, prostate, and Wilms' tumors (10,11). Expression of BORIS is restricted to spermatocytes and is mutually exclusive of CTCF (3). In cells expressing BORIS, promoters of X-linked cancer-testis antigens like MAGE-A1 are demethylated and activated, but methylated and inactive in CTCF-expressing somatic cells (12). Like other testis specific proteins, BORIS is abnormally expressed in different cancers, such as breast cancer, and has a greater affinity than CTCF for DNA-binding sites, detracting from CTCF's potential tumor suppressing activity (1,3,13,14). Alternate Names 11 zinc finger transcriptional repressor; 11-zinc finger protein; CCCTC-binding factor; CCCTC-binding factor (zinc finger protein); CFAP108; CTCF; CTCFL paralog; FAP108; MRD21; Transcriptional repressor CTCF Specification REACTIVITY: H M R Mk SENSITIVITY: Endogenous MW (kDa): 140 SOURCE: Rabbit