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PMID: 19911388 Published · ppublish English Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Review

Unwinding protein complexes in ALTernative telomere maintenance.

Journal of cellular biochemistry ·Vol. 109 ·No. 1 ·2010-01-01 ·Pages 7-15

Bhattacharyya S, Sandy A, Groden J

Abstract

Telomeres are composed of specialized chromatin that includes DNA repair/recombination proteins, telomere DNA-binding proteins and a number of three dimensional nucleic acid structures including G-quartets and D-loops. A number of studies suggest that the BLM and WRN recQ-like helicases play important roles in recombination-mediated mechanisms of telomere elongation or Alternative Lengthening of Telomeres (ALT), processes that maintain/elongate telomeres in the absence of telomerase. BLM and WRN localize within ALT-associated nuclear bodies in telomerase-negative immortalized cell lines and interact with the telomere-specific proteins POT1, TRF1 and TRF2. Helicase activity is modulated by these interactions. BLM functions in DNA double-strand break repair processes such as non-homologous end joining, homologous recombination-mediated repair, resolution of stalled replication forks and synthesis-dependent strand annealing, although its precise functions at the telomeres are speculative. WRN also functions in DNA replication, recombination and repair, and in addition to its helicase domain, includes an exonuclease domain not found in other recQ-like helicases. The biochemical properties of BLM and WRN are, therefore, important in biological processes other than DNA replication, recombination and repair. In this review, we discuss some previous and recent findings of human rec-Q-like helicases and their role in telomere elongation during ALT processes.

MeSH Terms
Animals Humans RecQ Helicases/physiology Telomere/chemistry,physiology Telomere-Binding Proteins/physiology
Chemicals
Telomere-Binding Proteins RecQ Helicases
Authors & Affiliations
3 authors, click to expand affiliations / ORCID
Bhattacharyya Saumitri
Department of Molecular Virology, Immunology & Medical Genetics, The Ohio State University College of Medicine, 460 W 12th Avenue, 986 Biomedical Research Tower, Columbus, Ohio 43210-2207, USA.
Sandy April
Groden Joanna
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Article Info
Journal
Journal of cellular biochemistry
Abbr.
J Cell Biochem
ISSN
1097-4644
DOI
10.1002/jcb.22388
Published
2010-01-01
Pages
7-15
Language
English
Region
United States
NLM ID
8205768
PMCID
PMC2892175
Subset
IM
Grants
NCI NIH HHS · R01 CA117898 · United States
NCI NIH HHS · R01 CA117898-02 · United States
NCI NIH HHS · CA-117898 · United States
External Links
PubMed source DOI: 10.1002/jcb.22388 PMC Full Text View journal details
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