vivo genome editing using a high-efficiency TALEN system

The zebrafish (Danio rerio) is increasingly being used to study basic vertebrate biology and human disease using a rich array of in vivo genetic and molecular tools. However, the inability to readily modify the genome in a targeted fashion has been a bottleneck in the field. Here we show that improvements in artificial transcription activator-like effector nucleases (TALENs) provide a powerful new approach for targeted zebrafish genome editing and functional genomic applications1–5. Using the GoldyTALEN modified scaffold and zebrafish delivery system, we show this enhanced TALEN toolkit demonstrates a high efficiency in inducing locus-specific DNA breaks in somatic and germline tissues. At some loci, this efficacy approaches 100%, including biallelic conversion in somatic tissues that mimics phenotypes seen using morpholino *These authors contributed equally to this work. Author contribution statements WT designed and constructed full-length pT3TS-Tal vectors targeting Danio rerio crhr1 and crhr2 against exon sequences provided by KJC. DFC and SCF designed and produced the pT3TS-Tal and GoldyTALEN cloning vectors. DFC synthesized crhr1 and crhr2 TALEN mRNA from the pT3TS-Tal vectors. CGS designed and assembled ponzr1 TALENs and transferred TAL repeats fro