Acts both as a regulator of telomere function and as a transcription regulator. Involved in the regulation of telomere length and protection as a component of the shelterin complex (telosome). In contrast to other components of the shelterin complex, it is dispensible for telomere capping and does not participate in the protection of telomeres against non-homologous end-joining (NHEJ)-mediated repair. Instead, it is required to negatively regulate telomere recombination and is essential for repressing homology-directed repair (HDR), which can affect telomere length. Does not bind DNA directly: recruited to telomeric double-stranded 5'-TTAGGG-3' repeats via its interaction with TERF2. Independently of its function in telomeres, also acts as a transcription regulator: recruited to extratelomeric 5'- TTAGGG-3' sites via its association with TERF2 or other factors, and regulates gene expression. When cytoplasmic, associates with the I-kappa-B-kinase (IKK) complex and acts as a regulator of the NF-kappa-B signaling by promoting IKK-mediated phosphorylation of RELA/p65, leading to activate expression of NF-kappa-B target genes. Associates with the I-kappa-B-kinase (IKK) core complex, composed of CHUK, IKBKB and IKBKG. Homodimer. Component of the shelterin complex (telosome) composed of TERF1, TERF2, TINF2, TERF2IP ACD and POT1. Interacts with TERF2; the interaction is direct. Does not interact with TERF1. Interacts with SLX4/BTBD12. Ubiquitous. Highly expressed. Belongs to the RAP1 family. Note: This description may include information from UniProtKB.
Molecular Function: protein binding; telomeric DNA binding
Biological Process: activation of NF-kappaB transcription factor; negative regulation of DNA recombination at telomere; negative regulation of telomere maintenance; positive regulation of I-kappaB kinase/NF-kappaB cascade; positive regulation of peptidyl-serine phosphorylation; protection from non-homologous end joining at telomere; regulation of transcription, DNA-dependent; telomere capping; telomere maintenance; telomere maintenance via telomerase