While most of the machinery and pathways involved in
biosynthesis and processing of N-glycan structures have
been identified, the study of the biological role associated
with distinct plant N-glycan structures on individual proteins
has proved challenging so far (Strasser, 2014). More detailed
and comprehensive (glyco)proteomic approaches of different
organelles are needed for understanding the structure and
function of glycoproteins in a specific cellular environment.
Now Pedrazzini et al. (2016) reveal that the Arabidopsis tonoplast
is almost completely lacking glycoproteins with complex
N-glycans and even proteins with ER-derived N-glycans
are highly underrepresented.