Synergy between adjacent zinc fingers in sequence-specific DNA recognition
Synergy between adjacent zinc fingers in sequence-specific DNA recognition
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DOI：
10.1073/pnas.94.11.5617
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发表时间：
1997-05-27
影响因子：
11.1
通讯作者：
Klug, A
中科院分区：
文献类型：
--
作者：
Isalan, M;Choo, Y;Klug, A
类Zif268锌指通常被视为独立的DNA结合模块，每个模块在相邻但离散的亚位点指定三个碱基对。然而，晶体学证据表明，一个锌指的第二个螺旋位置也可与前一个锌指的亚位点发生接触。在此，我们针对蛋白质Zif268的三指DNA结合结构域以及一组变体表明，从指3删除假定的接触可影响对相邻三联体中5'碱基的结合特异性，该碱基是指2结合位点的一部分。这一发现表明类Zif268锌指可指定重叠的4 - bp亚位点，并且亚位点之间边界处的序列特异性源自相邻锌指之间的协同作用。这对具有新型DNA结合特异性的锌指的设计和筛选具有重要意义。
Zif268-like zinc fingers are generally regarded as independent DNA-binding modules that each specify three base pairs in adjacent, but discrete, subsites, However, crystallographic evidence suggests that a contact also can occur from the second helical position of one finger to the subsite of the preceding finger, Here we show for the three-finger DNA-binding domain of the protein Zif268, and a panel of variants, that deleting the putative contact from finger 3 can affect the binding specificity for the 5' base in the adjoining triplet, which forms part of the binding site of finger 2, This finding demonstrates that Zif268-like zinc fingers can specify overlapping 4-bp suhsites, and that sequence specificity at the boundary between subsites arises from synergy between adjacent fingers. This has important implications for the design and selection of zinc fingers with novel DNA binding specificities.