Telomeric repeat-binding factor 1 (TERF1)

Binds the telomeric double-stranded 5'-TTAGGG-3' repeat and negatively regulates telomere length. Involved in the regulation of the mitotic spindle.

Part of the shelterin complicated (telosome) that is involved in the regulation of telomere length and protection. Shelterin associates with arrays of double- stranded 5'-TTAGGG-3' repeats added by telomerase and protects chromosome ends; with no protective activity, telomeres are no longer concealed from the DNA damage surveillance and chromosome ends are inappropriately processed by DNA repair pathways.