Format

Send to:

Choose Destination
See comment in PubMed Commons below
Cell Cycle. 2012 Mar 1;11(5):998-1007. doi: 10.4161/cc.11.5.19483. Epub 2012 Mar 1.

Telomere proteins POT1, TRF1 and TRF2 augment long-patch base excision repair in vitro.

Author information

  • 1Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.

Abstract

Human telomeres consist of multiple tandem hexameric repeats, each containing a guanine triplet. Guanosine-rich clusters are highly susceptible to oxidative base damage, necessitating base excision repair (BER). Previous demonstration of enhanced strand displacement synthesis by the BER component DNA polymerase β in the presence of telomere protein TRF2 suggests that telomeres employ long-patch (LP) BER. Earlier analyses in vitro showed that efficiency of BER reactions is reduced in the DNA-histone environment of chromatin. Evidence presented here indicates that BER is promoted at telomeres. We found that the three proteins that contact telomere DNA, POT1, TRF1 and TRF2, enhance the rate of individual steps of LP-BER and stimulate the complete reconstituted LP-BER pathway. Thought to protect telomere DNA from degradation, these proteins still apparently evolved to allow selective access of repair proteins.

PMID:
22336916
[PubMed - indexed for MEDLINE]
PMCID:
PMC3323798
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Landes Bioscience Icon for PubMed Central
    Loading ...
    Write to the Help Desk