Fluorescent tagged analysis of neural gene function using mosaics in zebrafish and Xenopus laevis.

An important question in the neurosciences is the role of specific gene expression in the control of neural morphology and connectivity. To address this question, methods are needed for expression of exogenous genes in a subset of neurons. This limited and mosaic expression allows the assessment of gene expression in a cell autonomous fashion without environmental contributions from neighboring expressing cells. These methods must also label neurons so that detailed morphology and neural connections can be evaluated. The labeling method should label only a subset of neurons so that neuronal morphology can be viewed upon a non-stained background, in a Golgi staining fashion. Here, we report methods using plasmids called pTAGUM (tagged analysis of genes using mosaics) that accomplish these goals. These methods should prove useful for the analysis of neural gene function in two important model organisms, the zebrafish and Xenopus laevis.