Читать книгу DNA Origami - Группа авторов - Страница 18

1.5.2 Selective Placement of Functional Molecules and Proteins via Ligands

Оглавление

Proteins have been selectively attached to the DNA origami structures by conjugating ligands and aptamers to staple strands [39–42]. The combination of specific proteins and ligands, such as SNAP‐tag and Halo‐tag, was also used for the selective placement of fusion proteins on DNA origami (Figure 1.6b) [36]. Zn‐finger proteins are sequence‐selective DNA‐binding molecules, and the specific binding sequence can be determined by designing the amino acid sequences [43, 44]. Using DNA origami with five cavities, we introduced substrate DNA strands with recognition sequences into each cavity [45]. The Zn‐finger proteins directly bound to the cavity containing the target sequence with 50–80% yield. In addition, GFP‐fused Zn‐finger proteins retained sequence‐specific recognition ability, albeit with a lower binding affinity. These results show that proteins can be directly targeted to specific sites using sequence‐selective Zn‐finger proteins. In addition, a sequence‐specific DNA recognition molecule, pyrrole‐imidazole polyamide was able to recognize and bind to the target sequences on DNA origami [46, 47]. We used a DNA origami structure with five cavities, into which five different sequences were incorporated. We visualized the selective alkylation of a biotinylated polyamide to the target sequence with streptavidin labeling. Using this method, the polyamide was found to alkylate the target sequence in 88% yield by discriminating one‐base mismatches. Selective alkylation and subsequent streptavidin labeling revealed the sequence selectivity of the polyamide at the single‐molecule level.

DNA Origami

Подняться наверх