TRANSIENT ANALYSIS OF GENE EXPRESSION IN PLANT CELLS
Transient expression of genes in plant cells is a powerful tool in plant molecular biology. Though many investigators use this technique to study plant promoter and upstream regulatory elements, it can also be used to study RNA translation 1 and polyadenylation.1 excision of transposable elements;1 and many other areas of plant biology. The major advantage of transient assays is time. Studying stably transformed plants may take several weeks to several months, while studying transient assays takes only a matter of days. Expedient assay time is balanced by the limitations of using protoplasts. Protoplasts do not represent nonnal plant cells, and it is strongly suggested that, if possible, constructs assayed in a transient system should also be assayed in stably transformed plants. This chapter focuses on using transient assays to study promoter and upstream regulatory elements fused to a P-glucuronidase reporter gene. but the principles described here are equally applicable to other problems.