Difference between revisions of "Part:BBa K1189023"

Revision as of 03:37, 27 September 2013

TALE-B

Transcriptor Activator-Like Effectors (TALEs) are proteins produced by bacteria of the genus Xanthomonas and secreted into plant cells. These naturally occurring TALEs play a key role in bacterial infection, as they are responsible for up regulation of the host genes required for pathogenic growth and expansion (Mussolino & Cathomen, 2012). These special bacterial plant pathogen proteins bind to DNA by specifically recognizing one base pair with a single tandem repeat in their DNA-binding domain. TALEs are an advantageous tool in synthetic biology because they can be modified to bind to a chosen DNA sequence. The central region of the protein, also termed repeat region, mediates DNA recognition through tandem repeats of 33 to 35 amino acids residues each (Bogdanove et al., 2010). The binding domain usually comprises 15.5 to 19.5 single repeats. The last repeat, close to the C-terminus, is called “half-repeat” because it is only approximately 20 amino acids in length. Although the modules have conserved sequences, polymorphisms are found in residues 12 and 13, the “repeat-variable di-residue” (RVD). RVDs are specific for a single nucleotide; therefore, 19.5 repeat units target a specific 20-nucleotide sequence in the DNA (Mussolino & Cathomen, 2012).

Sequence and Features