Reporter Genes and Transient Assays for Plants

The introduction of DNA into plant cells, protoplasts, or intact tissues has been accomplished by a variety of mechanisms, including electroporation, electrofusion, particle bombardment, liposome transfer, the use of bacterial vectors, polyethylene glycol treatment, and other procedures. As new techniques are developed or modified, it is necessary to use a reliable gene-expression system to monitor DNA uptake, transcription, and translation. A series of DNA plasmids containing reporter genes encoding readily assayed enzymes are available for this purpose. Several reporter gene systems have been used in experiments to transform plants and to perform transient assays with plant material. In general, these reporter genes encode enzymes whose activities can be detected through assays and stains, thus facilitating the identification of transformed cells and quantification of the transformation process. Reporter genes also provide a method for analyzing regulatory characteristics of promoters, such as promoter strength and tissue specificity, when the promoter from a gene of interest is coupled to the reporter gene.