Histochemical techniques for locating Escherichia coli β-galactosidase activity in transgenic organisms

Abstract

Escherichia coli β-galactosidase is a commonly used reporter molecule for analyzing gene expression. Recently, β-galactosidase fusions have been applied to a variety of eukaryotic systems. The techniques for constructing and introducing β-galactosidase fusion constructs as well as soluble assays for total enzyme function have been described in detail elsewhere. This article describes histochemical techniques for analyzing organisms that contain a functional β-galactosidase fusion construct. The object is to determine semiquantitatively which cells are expressing the βαlactosidase fusion protein, as well as the subcellular localization of the protein. Due to its prevalence in the author's laboratory, Caenorhabditis elegans is used as a canonical organism for the detailed methods described. © 1992.