Microinjection of Xenopus oocytes

Xenopus oocytes can be injected with messenger RNA (mRNA) or DNA constructs into the cytoplasm or nucleus, respectively. The cytoplasm can withstand the introduction of up to 50 nL of injected material, and the nucleus can tolerate up to 20 nL. This protocol describes microinjection of both defolliculated and folliculated Xenopus oocytes. Oocytes remain in good condition for a relatively long time, and injections can be continued, if necessary, over a period of days.