Using two TALEN pairs to delete the entire human miR-155 hairpin sequence.

(A) TALEN pairs targeting miR-155 were designed and constructed (called TALEN C). The upper panel shows a schematic of the TALEN A pair binding sites. The lower panel shows the sequence alignments comparing Wt and TALEN C mutated miR-155. The left and right TALEN binding sites are highlighted in yellow and the miR-155 seed region is boxed in red. (B) Schematic of the binding sites of two TALEN pairs (TALEN A and TALEN C) targeting miR-155. (C–D) Both TALEN A and TALEN C pairs were transfected into 293T cells. The miR-155 locus was amplified by PCR and subjected to TOPO cloning and sequencing. (C) Electrophoresis gel analysis showing deletions in the miR-155 locus. The arrows on the right indicate the two expected PCR products with or without large deletions. (D) Sequence alignments between a Wt clone and two TOPO clones with large deletions. The left and right TALEN binding sites for both TALEN A and TALEN C are highlighted in yellow and the miR-155 hairpin sequence is boxed in red.