5USB

Crystal Structure of Schizosaccharomyces pombe Pot1pC bound to ssRNA/ssDNA chimera (rGGTTACGGT)

5USB の概要

• エントリーDOI: 10.2210/pdb5usb/pdb
• 関連するPDBエントリー: 4HIK 5USN 5USO
• 分子名称: Protection of telomeres protein 1, G1R_9mer DNA/RNA (5'-R(*G)-D(P*GP*TP*TP*AP*CP*GP*GP*T)-3') (3 entities in total)
• 機能のキーワード: telomeres, ob-fold, dna binding, dna binding protein-dna-rna complex, dna binding protein/dna/rna
• 由来する生物種: Schizosaccharomyces pombe (Fission yeast); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 19524.74

構造登録者

Lloyd, N.R.,Wuttke, D.S. (登録日: 2017-02-13, 公開日: 2018-04-18, 最終更新日: 2023-10-04)

主引用文献

Lloyd, N.R.,Wuttke, D.S.
Discrimination against RNA Backbones by a ssDNA Binding Protein.
Structure, 26:722-733.e2, 2018

PubMed Abstract: Pot1 is the shelterin component responsible for the protection of the single-stranded DNA (ssDNA) overhang at telomeres in nearly all eukaryotic organisms. The C-terminal domain of the DNA-binding domain, Pot1pC, exhibits non-specific ssDNA recognition, achieved through thermodynamically equivalent alternative binding conformations. Given this flexibility, it is unclear how specificity for ssDNA over RNA, an activity required for biological function, is achieved. Examination of the ribose-position specificity of Pot1pC shows that ssDNA specificity is additive but not uniformly distributed across the ligand. High-resolution structures of several Pot1pC complexes with RNA-DNA chimeric ligands reveal Pot1pC discriminates against RNA by utilizing non-compensatory binding modes that feature significant rearrangement of the binding interface. These alternative conformations, accessed through both ligand and protein flexibility, recover much, but not all, of the binding energy, leading to the observed reduction in affinities. These findings suggest that intermolecular interfaces are remarkably sophisticated in their tuning of specificity toward flexible ligands.

PubMed: 29681468
DOI: 10.1016/j.str.2018.03.016

実験手法

X-RAY DIFFRACTION (1.615 Å)