A novel method for microinjection into Xenopus eggs and embryos supported in methylcellulose solution.

We have developed a novel method for microinjection into Xenopus eggs and embryos. Microinjection was performed into eggs or embryos that were placed in wells (ca. 2.5 mm x 2.5 mm x 0.8 mm for each well) at the bottom of a commercially available hybridoma dish, which was filled with 1.5% methylcellulose solution. Eggs or embryos, rotated to a desired orientation in the viscous methylcellulose solution with a hair loop, could remain in the orientation for more than twenty minutes. Accordingly, samples such as mRNAs, DNAs, proteins and antisense morpholino oligonucleotides could be easily and efficiently microinjected into any part (animal, vegetal, dorsal, lateral or ventral) of more than five hundred eggs and embryos in one day. In addition, methylcellulose did not interfere with the development of the injected eggs and embryos.