Tagging and Capture of Prenylated CaaX-Proteins from Plant Cell Cultures.

The tagging-via-substrate strategy allows the probing of in vivo post-translationally modified proteins thanks to a labeled substrate. This method has been used for the detection and proteomic analysis of prenylated proteins in mammals and more recently in plants. It consists of the labeling of prenylated proteins by supplying azido-prenyl to cells. The azido-prenylated proteins are then selectively linked to biotin alkyne, which allows their capture using streptavidin beads, and their subsequent identification by mass spectrometry. In this chapter, we describe this procedure on Arabidopsis cell suspension and how it can be applied for Catharanthus roseus cells.