title: Human telomere POT1-TPP1 complex and its role in telomerase activity regulation.
abstract: Telomeres, the specialized DNA-protein complexes found at the termini of all linear eukaryotic -chromosomes, protect chromosomes from degradation and end-to-end fusion. The protection of telomeres 1 (POT1) protein binds the single-stranded overhang at the ends of chromosomes in diverse eukaryotes. It is essential for chromosome end-protection and involved in telomere length regulation. TPP1 is a previously identified binding partner of POT1 that has been proposed to form part of a -six-protein shelterin complex at telomeres. Through structural and biochemical studies, we have -demonstrated that human TPP1 is the missing human homolog of the β subunit of protozoan telomere end-binding-protein-complex (TEBPα-TEBPβ). Therefore, capping of telomeres by a TEBPα-TEBPβ/POT1-TPP1 dimer is more evolutionarily conserved than that had been expected. In addition, we also discovered that the human POT1-TPP1 complex is a processivity factor for telomerase.
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, University of Michigan Medical School, Ann Arbor, MI, USA.
authors: Feng
authors: F
authors: Wang
authors: Ming
authors: M
authors: Lei
mesh_terms: D006801:Humans; D000089804:Shelterin Complex; D019098:Telomerase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D034501:Telomere-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: C495876:ACD protein, human; C440849:POT1 protein, human; D000089804:Shelterin Complex; D034501:Telomere-Binding Proteins; D019098:Telomerase