de Lange Orlando, Wolf Christina, Dietze Jörn, Elsaesser Janett, Morbitzer Robert, Lahaye Thomas
Genetics, Department of Biology I, Ludwig-Maximilians-University Munich, Martinsried, Bavaria, 82152, Germany.
Genetics, Department of Biology I, Ludwig-Maximilians-University Munich, Martinsried, Bavaria, 82152, Germany
Nucleic Acids Res. 2014 Jun;42(11):7436-49. doi: 10.1093/nar/gku329. Epub 2014 May 3.
The tandem repeats of transcription activator like effectors (TALEs) mediate sequence-specific DNA binding using a simple code. Naturally, TALEs are injected by Xanthomonas bacteria into plant cells to manipulate the host transcriptome. In the laboratory TALE DNA binding domains are reprogrammed and used to target a fused functional domain to a genomic locus of choice. Research into the natural diversity of TALE-like proteins may provide resources for the further improvement of current TALE technology. Here we describe TALE-like proteins from the endosymbiotic bacterium Burkholderia rhizoxinica, termed Bat proteins. Bat repeat domains mediate sequence-specific DNA binding with the same code as TALEs, despite less than 40% sequence identity. We show that Bat proteins can be adapted for use as transcription factors and nucleases and that sequence preferences can be reprogrammed. Unlike TALEs, the core repeats of each Bat protein are highly polymorphic. This feature allowed us to explore alternative strategies for the design of custom Bat repeat arrays, providing novel insights into the functional relevance of non-RVD residues. The Bat proteins offer fertile grounds for research into the creation of improved programmable DNA-binding proteins and comparative insights into TALE-like evolution.
转录激活样效应因子（TALEs）的串联重复序列利用一种简单的编码方式介导序列特异性DNA结合。天然情况下，TALEs由黄单胞菌属细菌注入植物细胞以操控宿主转录组。在实验室中，TALE DNA结合结构域被重新编程，并用于将融合的功能结构域靶向到选定的基因组位点。对类TALE蛋白自然多样性的研究可能为进一步改进当前的TALE技术提供资源。在此，我们描述了来自内共生细菌伯克霍尔德氏菌根毒素的类TALE蛋白，称为Bat蛋白。Bat重复结构域以与TALEs相同的编码方式介导序列特异性DNA结合，尽管序列同一性低于40%。我们表明，Bat蛋白可被改造用作转录因子和核酸酶，并且序列偏好可以重新编程。与TALEs不同，每个Bat蛋白的核心重复序列具有高度多态性。这一特性使我们能够探索设计定制Bat重复阵列的替代策略，为非RVD残基的功能相关性提供了新的见解。Bat蛋白为研究创建改进的可编程DNA结合蛋白以及对类TALE进化的比较性见解提供了丰富的研究基础。
