An important facet of the study of polyadenylation in plants entails the use of transient expression to characterize poly(A) sites and the subunits of the polyadenylation complex. In this report, a simple and adaptable approach to transient expression in Nicotiana benthamiana leaves is described. This approach has been used to evaluate protein-protein interactions amongst different plant polyadenylation factor subunits and to study the usage and behavior of individual poly(A) sites from plant genes.