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Single particle cryo-EM of the human CST•Polα/Primase (POLA1ΔN) complex in a recruitment state

ABSTRACT:

SUBMITTER: Titia de Lange

PROVIDER: EMPIAR-11131 | biostudies-other |

REPOSITORIES: biostudies-other

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Cryo-EM structure of the human CST-Polα/primase complex in a recruitment state.

Cai Sarah W SW Zinder John C JC Svetlov Vladimir V Bush Martin W MW Nudler Evgeny E Walz Thomas T de Lange Titia T

Nature structural & molecular biology 20220516 8

The CST-Polα/primase complex is essential for telomere maintenance and functions to counteract resection at double-strand breaks. We report a 4.6-Å resolution cryo-EM structure of human CST-Polα/primase, captured prior to catalysis in a recruitment state stabilized by chemical cross-linking. Our structure reveals an evolutionarily conserved interaction between the C-terminal domain of the catalytic POLA1 subunit and an N-terminal expansion in metazoan CTC1. Cross-linking mass spectrometry and ne ...[more]

PMID: 35578024

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Cryo-EM structure of the human CST-Polα/primase complex in a recruitment state.

Project description:The CST-Polα/primase complex is essential for telomere maintenance and functions to counteract resection at double-strand breaks. We report a 4.6-Å resolution cryo-EM structure of human CST-Polα/primase, captured prior to catalysis in a recruitment state stabilized by chemical cross-linking. Our structure reveals an evolutionarily conserved interaction between the C-terminal domain of the catalytic POLA1 subunit and an N-terminal expansion in metazoan CTC1. Cross-linking mass spectrometry and negative-stain EM analysis provide insight into CST binding by the flexible POLA1 N-terminus. Finally, Coats plus syndrome disease mutations previously characterized to disrupt formation of the CST-Polα/primase complex map to protein-protein interfaces observed in the recruitment state. Together, our results shed light on the architecture and stoichiometry of the metazoan fill-in machinery.

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