4m8o
From Proteopedia
TERNARY COMPLEX OF DNA POLYMERASE EPSILON WITH AN INCOMING dATP
Structural highlights
FunctionDPOE_YEAST DNA polymerase epsilon (DNA polymerase II) participates in chromosomal DNA replication. It is required during synthesis of the leading and lagging DNA strands at the replication fork and binds at/or near replication origins and moves along DNA with the replication fork. It has 3'-5' proofreading exonuclease activity that correct errors arising during DNA replication. It is also involved in DNA synthesis during DNA repair.[1] Publication Abstract from PubMedDNA polymerase varepsilon (Pol varepsilon) is a high-fidelity polymerase that has been shown to participate in leading-strand synthesis during DNA replication in eukaryotic cells. We present here a ternary structure of the catalytic core of Pol varepsilon (142 kDa) from Saccharomyces cerevisiae in complex with DNA and an incoming nucleotide. This structure provides information about the selection of the correct nucleotide and the positions of amino acids that might be critical for proofreading activity. Pol varepsilon has the highest fidelity among B-family polymerases despite the absence of an extended beta-hairpin loop that is required for high-fidelity replication by other B-family polymerases. Moreover, the catalytic core has a new domain that allows Pol varepsilon to encircle the nascent double-stranded DNA. Altogether, the structure provides an explanation for the high processivity and high fidelity of leading-strand DNA synthesis in eukaryotes. Structural basis for processive DNA synthesis by yeast DNA polymerase varepsilon.,Hogg M, Osterman P, Bylund GO, Ganai RA, Lundstrom EB, Sauer-Eriksson AE, Johansson E Nat Struct Mol Biol. 2014 Jan;21(1):49-55. doi: 10.1038/nsmb.2712. Epub 2013 Dec , 1. PMID:24292646[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|