TAL effector: Difference between revisions
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N-terminal to the canonical repeats, the PthXo1 structure reveals two degenerate repeat folds that appear to cooperate to specify the conserved thymine that precedes the RVD-specified sequence (Figure 4). We have designated these as the 0th and -1st repeats. Residues 221 to 239 and residues 256 to 273 each form a helix and an adjoining loop that resembles helix 1 and the RVD loop in the canonical repeats; the remaining residues in each region are poorly ordered. Those two N-terminal regions converge near the 5′ thymine base, with the indole ring of tryptophan 232 (in the -1st repeat) making a van der Waals contact with the methyl group of that base. Mutation of the thymine reduces TAL effector activity at the target (3, 15). Tryptophan 232, as well as the surrounding residues, is highly conserved across available, intact TAL effector sequences. | N-terminal to the canonical repeats, the PthXo1 structure reveals two degenerate repeat folds that appear to cooperate to specify the conserved thymine that precedes the RVD-specified sequence (Figure 4). We have designated these as the 0th and -1st repeats. Residues 221 to 239 and residues 256 to 273 each form a helix and an adjoining loop that resembles helix 1 and the RVD loop in the canonical repeats; the remaining residues in each region are poorly ordered. Those two N-terminal regions converge near the 5′ thymine base, with the indole ring of tryptophan 232 (in the -1st repeat) making a van der Waals contact with the methyl group of that base. Mutation of the thymine reduces TAL effector activity at the target (3, 15). Tryptophan 232, as well as the surrounding residues, is highly conserved across available, intact TAL effector sequences. | ||
==Engineering== | <!-- ==Engineering== | ||
<br>[[Image:iGEM.png|left|500px|thumb|Fig.4]]<br> | <br>[[Image:iGEM.png|left|500px|thumb|Fig.4]]<br> | ||
'''Figure 4''': Based on the RVD the construction of a so called GATE Assembly kit was performed by the [[iGem 2012 Team]] from Freiburg University. | '''Figure 4''': Based on the RVD the construction of a so called GATE Assembly kit was performed by the [[iGem 2012 Team]] from Freiburg University. | ||
<ref> http://2012.igem.org/Team:Freiburg/Project/Tal </ref> | <ref> http://2012.igem.org/Team:Freiburg/Project/Tal </ref> --> | ||