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Updated: Jul 10, 2026
09:30
Genome-wide Surveillance of Transcription Errors in Eukaryotic Organisms
Published on: September 13, 2018
Why do cells have multiple error-prone DNA polymerases?
1Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9072, USA.
Environmental and Molecular Mutagenesis
|December 18, 2001
Summary
Researchers discovered numerous novel DNA polymerases in cells. Many exhibit low accuracy and processivity, lacking proofreading ability, and their biological roles are being investigated.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Recent years have seen the discovery of many new DNA polymerases in eukaryotic and prokaryotic organisms.
- These novel enzymes often display suboptimal enzymatic properties.
Purpose of the Study:
- To describe the discovery of novel DNA polymerases.
- To elucidate the biological functions of these newly identified enzymes.
Main Methods:
- Literature review of recent discoveries.
- Analysis of reported biochemical and genetic data.
Main Results:
- Identification of numerous novel DNA polymerases across different cell types.
- Characterization of these polymerases reveals poor replicational fidelity and low processivity.
- Absence of 3' to 5' exonuclease activity is a common feature.
Conclusions:
- The emergence of error-prone DNA polymerases is a significant recent finding in molecular biology.
- Further research is needed to fully understand the biological roles and implications of these enzymes in cellular processes.
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