Transient secretory enzyme expression in leaf protoplasts to characterize snare functional classes in conventional and unconventional secretion

Despite a long case history, the use of protoplasts in cell biology research still divides scientists but their weaknesses can be exploited as strengths. Transient expression in protoplasts can saturate protein–protein interactions very efficiently, inhibiting the process of interest more efficiently than other approaches at gene expression level. The method described here consists of an assay providing a functional characterization of SNARE proteins in a heterogeneous population of cells, by the comparison of native and dominant negative mutant forms. In particular, it allows for discriminating between t-SNARE and i-SNARE functional classes.