Takatsuji H
National Institute of Agrobiological Resources, Ibaraki, Japan.
Biochem Biophys Res Commun. 1996 Jul 5;224(1):219-23. doi: 10.1006/bbrc.1996.1010.
The EPF family is a group of DNA-binding proteins with two canonical Cys2/His2 zinc-finger motifs in Petunia. These proteins are unique in terms of structure in that (i) the two zinc fingers are separated by spacers of various lengths and (ii) the sequence QALGGH is strongly conserved in the zinc-finger motifs of members of the family. In this study, domain-swapping and site-directed mutagenesis experiments with two members of the protein family, EPF2-5 and EPF2-7, which have different target sequences, revealed that only a single amino acid in the second zinc finger is responsible for the difference in target specificity. The position of this amino acid is different from those of determinants of target-sequence specificity in other zinc-finger proteins. Thus, the EPF family recognizes target sequences in a unique manner, together with the recognition of spacings in the target sequence that we demonstrated recently.
EPF家族是矮牵牛中一组具有两个典型Cys2/His2锌指基序的DNA结合蛋白。这些蛋白质在结构上具有独特性，表现为：（i）两个锌指被不同长度的间隔区隔开；（ii）序列QALGGH在该家族成员的锌指基序中高度保守。在本研究中，对该蛋白家族中具有不同靶序列的两个成员EPF2-5和EPF2-7进行结构域交换和定点诱变实验，结果表明，第二个锌指中仅有一个氨基酸决定了靶标特异性的差异。该氨基酸的位置与其他锌指蛋白中靶序列特异性决定因素的位置不同。因此，EPF家族以独特的方式识别靶序列，同时还能识别我们最近证实的靶序列中的间隔区。
