Location, location, location: Trafficking and localisation of Golgi-resident N-glycan processing enzymes in plants

Jennifer Schoberer^*Kai Dünser

• University of Natural Resources and Life Sciences Vienna, Vienna, Austria

Asparagine (N)-linked glycosylation is a fundamental co-and post-translational modification of proteins, playing a crucial role in protein folding, stability and function, protein-protein interactions, biotic and abiotic stress response as well as glycan-dependent quality control processes in the endoplasmic reticulum (ER). Most proteins entering the secretory pathway are N-glycosylated, although the exact number in the plant N-glycoproteome is unknown. Protein N-glycosylation is initiated in the ER and continued in the Golgi apparatus by N-glycan-processing glycosyltransferases and glycosidases, which are compartmentalised in a highly organised manner reflecting their function in the sequential modification of glycans. Therefore, the precise localisation of these enzymes is crucial for the optimal functioning of the glycosylation process and the secretory pathway and hence must be tightly regulated to maintain protein function, cellular health, and overall organismal development. Here, we highlight recent developments that contribute to a better understanding of the localisation mechanisms of this important class of Golgi residents and discuss future directions to move the field forward.