Abstract
This protocol details the oocyte host-transfer method in Xenopus, using transplantation by intraperitoneal injection. This approach is suitable for the overexpression of mRNAs and for the use of antisense oligonucleotides to deplete maternal mRNAs, which are not replaced until zygotic genome activation in the mid-blastula transition. Xenopus oocyte host-transfer can also be used for highly efficient mutagenesis in the F0 generation by prefertilization injection of genome editing reagents.