The maize ID1 flowering time regulator is a zinc finger protein with novel DNA binding properties
The maize ID1 flowering time regulator is a zinc finger protein with novel DNA binding properties
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DOI：
10.1093/nar/gkh337
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发表时间：
2004-03-01
影响因子：
14.9
通讯作者：
Colasanti, J
中科院分区：
文献类型：
--
作者：
Kozaki, A;Hake, S;Colasanti, J
不确定蛋白ID1在调节玉米到开花的过渡过程中起关键作用。ID1是植物特有的锌指蛋白家族的创始成员，该家族由高度保守的氨基酸序列定义，称为ID结构域。ID结构域包括由三个不同类型的锌指组成的簇，这些锌指与第四个C2H2指通过一个长的间隔物隔开；ID1与其他ID结构域蛋白的不同之处在于它有一个更长的间隔物。体外DNA选择、扩增结合实验和DNA结合实验表明，ID1通过ID结构域选择性地与11个碱基的一致基序结合。出人意料的是，ID1蛋白的定点突变表明，位于ID结构域两端的锌指不是与共识基序结合所必需的，尽管其中一个锌指是典型的C2H2 DNA结合域。此外，缺乏锌指间额外间隔区的ID1体外缺失突变体与正常ID1结合了相同的11bp基序，这表明所有含有ID结构域的蛋白质都识别相同的DNA靶序列。我们的结果表明，玉米ID1和ID结构域蛋白具有新颖的锌指结构，具有独特的DNA结合特性。
The INDETERMINATE protein, ID1, plays a key role in regulating the transition to flowering in maize. ID1 is the founding member of a plant-specific zinc finger protein family that is defined by a highly conserved amino sequence called the ID domain. The ID domain includes a cluster of three different types of zinc fingers separated from a fourth C2H2 finger by a long spacer; ID1 is distinct from other ID domain proteins by having a much longer spacer. In vitro DNA selection and amplification binding assays and DNA binding experiments showed that ID1 binds selectively to an 11 bp consensus motif via the ID domain. Unexpectedly, site-directed mutagenesis of the ID1 protein showed that zinc fingers located at each end of the ID domain are not required for binding to the consensus motif despite the fact that one of these zinc fingers is a canonical C2H2 DNA binding domain. In addition, an ID1 in vitro deletion mutant that lacks the extra spacer between zinc fingers binds the same 11 bp motif as normal ID1, suggesting that all ID domain-containing proteins recognize the same DNA target sequence. Our results demonstrate that maize ID1 and ID domain proteins have novel zinc finger configurations with unique DNA binding properties.