Whole-Mount Immunofluorescence for Visualizing Endogenous Protein and Injected RNA in Oocytes.

Asymmetric distribution of mRNA and protein is a hallmark of cell polarity in many systems. The oocyte provides many technical advantages to studying such polarity. Thousands of oocytes at different stages of maturity can be harvested from a single ovary and, owing to their relatively large size, even the youngest oocytes can be manually microinjected. Microinjection of fluorescently labeled RNA combined with immunofluorescence of endogenous proteins can provide insight into the cytoplasmic interactions contributing to polarity. Here, we present an updated method to image endogenous protein and microinjected RNA in oocytes.