Reporter Gene Systems for Assaying Gene Expression in Yeast

Reporter gene constructs are used to monitor the expression of genes whose natural product is not readily assayed. The most convenient reporters to use encode enzymes that catalyze a reaction that is easily monitored. Three useful reporter systems for intracellular expression will be described here: β-galactosidase (1 ), chloramphenicol acetyl transferase (CAT) (2 ,3 ), and aminoglycoside phosphotransferase (APT) (4 ). Each reporter has advantages and disadvantages according to the simplicity or the accuracy of the assay.