Maternal mRNA knock-down studies: antisense experiments using the host-transfer technique in Xenopus laevis and Xenopus tropicalis.

The ability to inhibit the activity of maternally stored gene products in Xenopus has led to numerous insights into early developmental mechanisms. Oocytes can be cultured and manipulated in vitro and then implanted into the body cavity of a host female to make them competent for fertilization. Here, we summarize the methods for obtaining, culturing, and fertilizing Xenopus oocytes, with the goal of inhibiting maternal gene function through antisense oligonucleotide-mediated mRNA knock-down. We describe a simplified technique for implanting donor oocytes into host females using intraperitoneal injection. Also, we present optimized methods for performing the host-transfer procedure with Xenopus tropicalis oocytes.