SNAP annotations: PDB entry 6gvq

PDB-id

6gvq; DSSR-derived features in text and JSON formats; DNAproDB

Class

DNA binding protein

Method

NMR

Summary

DNA-bound prn1 helix bundle domain with atp and magnesium in the interaction buffer

Reference

Boudet J, Devillier JC, Wiegand T, Salmon L, Meier BH, Lipps G, Allain FH (2019): "A Small Helical Bundle Prepares Primer Synthesis by Binding Two Nucleotides that Enhance Sequence-Specific Recognition of the DNA Template." Cell, 176, 154-166.e13. doi: 10.1016/j.cell.2018.11.031.

Abstract

Primases have a fundamental role in DNA replication. They synthesize a primer that is then extended by DNA polymerases. Archaeoeukaryotic primases require for synthesis a catalytic and an accessory domain, the exact contribution of the latter being unresolved. For the pRN1 archaeal primase, this domain is a 115-amino acid helix bundle domain (HBD). Our structural investigations of this small HBD by liquid- and solid-state nuclear magnetic resonance (NMR) revealed that only the HBD binds the DNA template. DNA binding becomes sequence-specific after a major allosteric change in the HBD, triggered by the binding of two nucleotide triphosphates. The spatial proximity of the two nucleotides and the DNA template in the quaternary structure of the HBD strongly suggests that this small domain brings together the substrates to prepare the first catalytic step of primer synthesis. This efficient mechanism is likely general for all archaeoeukaryotic primases.