POT1-TPP1 Binding and Unfolding of Telomere DNA Discriminates against Structural Polymorphism.

ABSTRACT: Telomeres are nucleoprotein complexes that reside at the ends of linear chromosomes and help maintain genomic integrity. Protection of telomeres 1 (POT1) and TPP1 are telomere-specific proteins that bind as a heterodimer to single-stranded telomere DNA to prevent illicit DNA damage responses and to enhance telomerase-mediated telomere extension. Telomere DNA is guanosine rich and, as such, can form highly stable secondary structures including G-quadruplexes. G-quadruplex DNA folds into different topologies that are determined by several factors including monovalent ion composition and the precise sequence and length of the DNA. Here, we explore the influence of DNA secondary structure on POT1-TPP1 binding. Equilibrium binding assays reveal that the POT1-TPP1 complex binds G-quadruplex stru

SUBMITTER: Mullins MR 

PROVIDER: S-EPMC4905795 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature