Targeted microinjection of synthetic mRNAs to alter retina gene expression in Xenopus embryos.

The individual cells of the Xenopus cleavage-stage embryo have been fate mapped, revealing which of these cells contribute to the retina. Using this retina fate map, one can specifically modulate levels of gene expression in retina lineages to determine the function of proteins in various aspects of early retinal development, such as formation of the eye fields and determination of specific cell fates. This chapter presents the techniques for identifying specific retina blastomere precursor cells, and injecting them with lineage tracers, mRNAs encoding wild-type and mutant constructs or morpholino antisense oligonucleotides to alter gene expression.