How the human telomeric proteins TRF1 and TRF2 recognize telomeric DNA: a view from high-resolution crystal structures

被引：182

作者：

Court, R ^{[1
]}

Chapman, L ^{[1
]}

Fairall, L ^{[1
]}

Rhodes, D ^{[1
]}

机构：

[1] MRC, Mol Biol Lab, Cambridge CB2 2QH, England

来源：

EMBO REPORTS | 2005年 / 6卷 / 01期

关键词：

telomeric DNA recognition; TRF1; TRF2; water-mediated contacts; x-ray crystallography;

D O I：

10.1038/sj.embor.7400314

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Human telomeres consist of tandem arrays of TTAGGG sequence repeats that are specifically bound by two proteins, TRF1 and TRF2. They bind to DNA as preformed homodimers and have the same architecture in which the DNA-binding domains (Dbds) form independent structural units. Despite these similarities, TRF1 and TRF2 have different functions at telomeres. The X-ray crystal structures of both TRF1- and TRF2-Dbds in complex with telomeric DNA (2.0 and 1.8 Angstrom resolution, respectively) show that they recognize the same TAGGGTT binding site by means of homeodomains, as does the yeast telomeric protein Rap1p. Two of the three G-C base pairs that characterize telomeric repeats are recognized specifically and an unusually large number of water molecules mediate protein-DNA interactions. The binding of the TRF2-Dbd to the DNA double helix shows no distortions that would account for the promotion of t-loops in which TRF2 has been implicated.

引用

页码：39 / 45

页数：7

共 43 条

[1] Methods used in the structure determination of bovine mitochondrial F-1 ATPase [J].