Telomerase RNA component (TERC), also abbreviated TER or TR, is a non-coding RNA found in eukaryotes that is a component of the telomerase enzyme, which extends telomeres at the ends of linear chromosomes. TERC folds into a complex secondary structure which binds to and interacts with TERT, the protein component of telomerase, and serves as the RNA template for the reverse transcription reaction catalyzed by TERT. Telomerase RNAs differ greatly in length, sequence and structure between vertebrates, ciliates and yeasts, but they share a 5' pseudoknot structure close to the template sequence; vertebrate telomerase RNAs also share a 3' H/ACA snoRNA-like domain.
