Structures of the human CST-Polα-primase complex bound to telomere templates.

ABSTRACT: The mammalian DNA polymerase-α-primase (Polα-primase) complex is essential for DNA metabolism, providing the de novo RNA-DNA primer for several DNA replication pathways^1-4 such as lagging-strand synthesis and telomere C-strand fill-in. The physical mechanism underlying how Polα-primase, alone or in partnership with accessory proteins, performs its complicated multistep primer synthesis function is unknown. Here we show that CST, a single-stranded DNA-binding accessory protein complex for Polα-primase, physically organizes the enzyme for efficient primer synthesis. Cryogenic electron microscopy structures of the CST-Polα-primase preinitiation complex (PIC) bound to various types of telomere overhang reveal that template-bound CST partitions the DNA and RNA catalytic centres of Po

SUBMITTER: He Q 

PROVIDER: S-EPMC10268231 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature