Injection of TALEN mRNAs into GV oocytes allows efficient tyrosinase gene disruption.

(A) Schematic diagram of the experiment to express TALENs in Xenopus laevis eggs before fertilization. (B) Development of tyrosinase (tyr) TALENs-expressed oocytes. TALEN mRNA-injected GV oocytes, followed by in vitro maturation and ICSI, were able to develop to the swimming tadpole stage although mRNA injection itself seems to decrease the developmental capacity of in vitro matured eggs. Actual numbers of embryos that were injected with sperm and that developed to each developmental stages are indicated next to the corresponding bars. (C-E) Expression of tyr TALENs in GV oocytes allowed almost complete albino phenotypes in F0 embryos and frogs. Enlarged pictures of two TALEN-RL-expressed tadpoles are shown in Fig 1D. Control R represents control embryos and frogs in which only right side TALEN was expressed.