Telomere-Binding Proteins

The telomeric repeat is double stranded for most of its length, but at the very end it is single stranded. Various proteins bind to telomeres, including POT1 (protection of telomeres 1), which binds to the single-stranded portion to protect telomere ends from degradation, and TRF1 (TTAGGG repeat binding factor 1), which binds to the double-stranded portion. Both help regulate telomerase activity.

A double helix with green ovals behind it labeled T-R-F-1 which becomes a single strand with blue ovals behind it labeled P-O-T-1.