SIGNALS AND MECHANISMS INVOLVED IN INTRACELLULAR-TRANSPORT OF SECRETED PROTEINS IN PLANTS

In plant cells, the secretory system delivers many different proteins to four principal locations: the cell wall, the vacuole, the plasma me mbrane and the tonoplast. All secretory proteins are co-translationnal ly inserted into the endoplasmic reticulum; they are next selectively targeted and/or retained in various intracellular compartments. Variou s molecular signals necessary for retention or targeting to the differ ent compartments have been identified recently. This review summarizes the advances in this field and the putative mechanisms involved in so rting of secreted proteins.