3vw4

Publication Abstract from PubMed

Duplex DNA is generally unwound by protein oligomers prior to replication. The Rep protein of plasmid ColE2-P9 (34 kDa) is an essential initiator for plasmid DNA replication. This protein binds the replication origin (Ori) in a sequence specific manner as a monomer and unwinds DNA. Here we present the crystal structure of the DNA-binding domain of Rep (E2Rep-DBD) in complex with Ori DNA. The structure unveils the basis for Ori specific recognition by the E2Rep-DBD and also reveals that it unwinds DNA by the concerted actions of its three contiguous structural modules. The structure also shows that the functionally unknown PriCT domain, which forms a compact module, plays a central role in DNA unwinding. The conservation of the PriCT domain in the C-termini of some archaeo-eukaryotic primases, indicates that it likely plays a similar role in these proteins. Thus, this is the first report providing the structural basis for the functional importance of the conserved PriCT domain and also reveals a novel mechanism for DNA unwinding by a single protein.

Structural Basis for Replication Origin Unwinding by An Initiator-Primase of Plasmid ColE2-P9: Duplex DNA Unwinding by A Single Protein.,Itou H, Yagura M, Shirakihara Y, Itoh T J Biol Chem. 2014 Dec 23. pii: jbc.M114.595645. PMID:25538245^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.