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Title: Close encounters: Moving along bumps, breaks, and bubbles on expanded trinucleotide tracts

Abstract

Expansion of simple triplet repeats (TNR) underlies greater than 30 severe degenerative diseases. There is a good understanding of the major pathways generating an expansion, and the associated polymerases that operate during gap filling synthesis at these “difficult to copy” sequences. However, the mechanism by which a TNR is repaired depends on the type of lesion, the structural features imposed by the lesion, the assembled replication/repair complex, and the polymerase that encounters it. The relationships among these parameters are exceptionally complex and how they direct pathway choice is poorly understood. In this review, we consider the properties of polymerases, and how encounters with GC-rich or abnormal structures might influence polymerase choice and the success of replication and repair. Insights over the last three years have highlighted new mechanisms that provide interesting choices to consider in protecting genome stability.

Authors:
 [1];  [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
National Institutes of Health (NIH); USDOE
OSTI Identifier:
1393247
DOE Contract Number:
AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: DNA Repair; Journal Volume: 56; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES

Citation Formats

Polyzos, Aris A., and McMurray, Cynthia T. Close encounters: Moving along bumps, breaks, and bubbles on expanded trinucleotide tracts. United States: N. p., 2017. Web. doi:10.1016/j.dnarep.2017.06.017.
Polyzos, Aris A., & McMurray, Cynthia T. Close encounters: Moving along bumps, breaks, and bubbles on expanded trinucleotide tracts. United States. doi:10.1016/j.dnarep.2017.06.017.
Polyzos, Aris A., and McMurray, Cynthia T. Fri . "Close encounters: Moving along bumps, breaks, and bubbles on expanded trinucleotide tracts". United States. doi:10.1016/j.dnarep.2017.06.017.
@article{osti_1393247,
title = {Close encounters: Moving along bumps, breaks, and bubbles on expanded trinucleotide tracts},
author = {Polyzos, Aris A. and McMurray, Cynthia T.},
abstractNote = {Expansion of simple triplet repeats (TNR) underlies greater than 30 severe degenerative diseases. There is a good understanding of the major pathways generating an expansion, and the associated polymerases that operate during gap filling synthesis at these “difficult to copy” sequences. However, the mechanism by which a TNR is repaired depends on the type of lesion, the structural features imposed by the lesion, the assembled replication/repair complex, and the polymerase that encounters it. The relationships among these parameters are exceptionally complex and how they direct pathway choice is poorly understood. In this review, we consider the properties of polymerases, and how encounters with GC-rich or abnormal structures might influence polymerase choice and the success of replication and repair. Insights over the last three years have highlighted new mechanisms that provide interesting choices to consider in protecting genome stability.},
doi = {10.1016/j.dnarep.2017.06.017},
journal = {DNA Repair},
number = C,
volume = 56,
place = {United States},
year = {Fri Jun 09 00:00:00 EDT 2017},
month = {Fri Jun 09 00:00:00 EDT 2017}
}
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