CTCF

Source: NCBI Gene, accessed 2026-10-07.

Protein

Transcriptional repressor CTCF

Function (excerpt)

Chromatin binding factor that binds to DNA sequence specific sites and regulates the 3D structure of chromatin. Binds together strands of DNA, thus forming chromatin loops, and anchors DNA to cellular structures, such as the nuclear lamina. Defines the boundaries between active and heterochromatic DNA via binding to chromatin insulators, thereby preventing interaction between promoter and nearby enhancers and silencers. Participates in the allele-specific gene expression at the imprinted IGF2/H19 gene locus. On the maternal allele, binding within the H19 imprinting control region (ICR) mediates maternally inherited higher-order chromatin conformation to restrict enhancer access to IGF2 (By similarity). Mediates interchromosomal association between IGF2/H19 and WSB1/NF1 and may direct distant DNA segments to a common transcription factory (By similarity). Regulates asynchronous replication of IGF2/H19 (By similarity).

Subcellular location

Nucleus, nucleoplasm; Chromosome; Chromosome, centromere.

Tissue specificity

Ubiquitous. Absent in primary spermatocytes.

Associated conditions

Intellectual developmental disorder, autosomal dominant 21 (MRD21).

Source: UniProtKB/Swiss-Prot P49711, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.

Written for the whole epigenetic regulation family, not for CTCF specifically.