A simple cipher governs DNA recognition by TAL Effectors

Department of Plant Pathology and Bioinformatics and Computational Biology Program, Iowa State University, Ames, IA 50011, USA.
Science (Impact Factor: 33.61). 10/2009; 326(5959):1501. DOI: 10.1126/science.1178817
Source: PubMed


TAL effectors of plant pathogenic bacteria in the genus Xanthomonas bind host DNA and activate genes that contribute to disease or turn on defense. Target specificity depends on an effector-variable number of typically 34 amino acid repeats, but the mechanism of recognition is not understood. We show that a repeat-variable pair of residues specifies the nucleotides in the target site, one pair to one nucleotide, with no apparent context dependence. Our finding represents a previously unknown mechanism for protein-DNA recognition that explains TAL effector specificity, enables target site prediction, and opens prospects for use of TAL effectors in research and biotechnology.

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Available from: Matthew J Moscou, Mar 11, 2015
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    • "Transgenesis is a powerful technique for both gain-of-function analysis and for loss-of-function experiments. New tools for targeted mutations and genetic engineering include zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), clustered regularly interspaced short palindromic repeat/CRISPR-associated system (CRISPR/Cas9) [7] [8] [9] [10] [11] [12] [13], and DNA transposon-based approaches [14] [15] [16]. "
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    Biotechnology Journal 10/2015; DOI:10.1002/biot.201500218 · 3.49 Impact Factor
    • "Sequences of TALE repeats are highly conserved and differ mainly in two amino acid residues at positions 12 and 13, known as the repeat variable di-residues (RVDs). TALEs observe a simple cipher for DNA recognition where each repeat independently binds one nucleotide in the target DNA sequence as specified by the RVDs (where NI = A, HD = C, NG = T, NN = G or A) [23] [24]. "
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    • "Based on the knowledge of the TAL-effector DNA binding code (Boch et al., 2009; Moscou & Bogdanove, 2009 ), we identified xa41(t) in accessions of the African wild and cultivated rice species O. barthii and O. glaberrima. xa41(t) confers broad-spectrum resistance due to a 18-bp deletion in the promoter of the major bacterial blight susceptibility gene OsSWEET14. "
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