Preparation and use of reporter constructs for imaging morphogenesis in Xenopus embryos

To understand dynamic cell and tissue mechanics during Xenopus laevis morphogenesis requires the use of live reporters of cell architecture as well as reporters for the location and activity of proteins in cells within a multicellular tissue. Fluorescently tagged proteins are some of the most useful reporters for live cell work. These fluorescent reporters are either proteins conjugated to small fluorochromes or molecularly engineered chimeric fluorescent proteins, and they can be distributed evenly across a tissue or localized within a subset of cells. An evenly distributed reporter is useful when visualizing patterns of protein localization within a field of cells. Alternatively, restricting the expression of a reporter to single cells or patches of cells in a mosaic can reveal patterns of subcellular localization. Here we discuss methods for synthesizing mRNA encoding fluorescent proteins and for expressing these proteins evenly as well as in scattered populations within a multicellular tissue.