The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy

Proofreading function by the 3′→ 5′ exonuclease of DNA polymerase δ (pol δ) is consistent with the observation that deficiency of the associated exonuclease can lead to a strong mutation phenotype, high error rates during DNA replication, and ultimately cancer. We have isolated pol δd from isotonic...

Full description

Saved in:
Bibliographic Details
Main Authors: Igor V. Shevelev, Kristijan Ramadan, Ulrich Hubscher
Format: Article
Language:English
Published: Wiley 2002-01-01
Series:The Scientific World Journal
Online Access:http://dx.doi.org/10.1100/tsw.2002.99
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850162974697717760
author Igor V. Shevelev
Kristijan Ramadan
Ulrich Hubscher
author_facet Igor V. Shevelev
Kristijan Ramadan
Ulrich Hubscher
author_sort Igor V. Shevelev
collection DOAJ
description Proofreading function by the 3′→ 5′ exonuclease of DNA polymerase δ (pol δ) is consistent with the observation that deficiency of the associated exonuclease can lead to a strong mutation phenotype, high error rates during DNA replication, and ultimately cancer. We have isolated pol δd from isotonic (pol δi) and detergent (pol δd) calf thymus extracts. Pol δd had a 20-fold higher ratio of exonuclease to DNA polymerase than pol δi. This was due to the physical association of the TREX2 exonuclease to pol δd, which was missing from pol δi. Pol δd was fivefold more accurate than pol δi under error-prone conditions (1 μM dGTP and 20 dATP, dCTP, and dTTP) in a M13mp2 DNA forward mutation assay, and fourfold more accurate in an M13mp2T90 reversion assay. Under error-free conditions (20 μM each of the four dNTPs), however, both polymerases showed equal fidelity. Our data suggested that autonomous 3′→ 5′ exonucleases, such as TREX2, through its association with pol I can guarantee high fidelity under difficult conditions in the cell (e.g., imbalance of dNTPs) and can add to the accuracy of the DNA replication machinery, thus preventing mutagenesis.
format Article
id doaj-art-eef236012efb4fb4980ec867e2e9e5c6
institution OA Journals
issn 1537-744X
language English
publishDate 2002-01-01
publisher Wiley
record_format Article
series The Scientific World Journal
spelling doaj-art-eef236012efb4fb4980ec867e2e9e5c62025-08-20T02:22:25ZengWileyThe Scientific World Journal1537-744X2002-01-01227528110.1100/tsw.2002.99The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its AccuracyIgor V. Shevelev0Kristijan Ramadan1Ulrich Hubscher2Institute of Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057, Zürich, SwitzerlandInstitute of Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057, Zürich, SwitzerlandInstitute of Veterinary Biochemistry and Molecular Biology, University of Zürich-Irchel, Winterthurerstrasse 190, CH-8057, Zürich, SwitzerlandProofreading function by the 3′→ 5′ exonuclease of DNA polymerase δ (pol δ) is consistent with the observation that deficiency of the associated exonuclease can lead to a strong mutation phenotype, high error rates during DNA replication, and ultimately cancer. We have isolated pol δd from isotonic (pol δi) and detergent (pol δd) calf thymus extracts. Pol δd had a 20-fold higher ratio of exonuclease to DNA polymerase than pol δi. This was due to the physical association of the TREX2 exonuclease to pol δd, which was missing from pol δi. Pol δd was fivefold more accurate than pol δi under error-prone conditions (1 μM dGTP and 20 dATP, dCTP, and dTTP) in a M13mp2 DNA forward mutation assay, and fourfold more accurate in an M13mp2T90 reversion assay. Under error-free conditions (20 μM each of the four dNTPs), however, both polymerases showed equal fidelity. Our data suggested that autonomous 3′→ 5′ exonucleases, such as TREX2, through its association with pol I can guarantee high fidelity under difficult conditions in the cell (e.g., imbalance of dNTPs) and can add to the accuracy of the DNA replication machinery, thus preventing mutagenesis.http://dx.doi.org/10.1100/tsw.2002.99
spellingShingle Igor V. Shevelev
Kristijan Ramadan
Ulrich Hubscher
The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
The Scientific World Journal
title The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
title_full The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
title_fullStr The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
title_full_unstemmed The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
title_short The TREX2 3′→ 5′ Exonuclease Physically Interacts with DNA Polymerase δ and Increases Its Accuracy
title_sort trex2 3 5 exonuclease physically interacts with dna polymerase δ and increases its accuracy
url http://dx.doi.org/10.1100/tsw.2002.99
work_keys_str_mv AT igorvshevelev thetrex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy
AT kristijanramadan thetrex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy
AT ulrichhubscher thetrex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy
AT igorvshevelev trex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy
AT kristijanramadan trex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy
AT ulrichhubscher trex235exonucleasephysicallyinteractswithdnapolymerasedandincreasesitsaccuracy