Maize and Arabidopsis Golgi proteome

Comparative proteomics of ER-Golgi membranes from etiolated coleoptiles of maize (Zea mays) and young leaves of Arabidopsis (Arabidopsis thaliana) isolated by flotation centrifugation demonstrate differences in the complement of synthases and glycosyl transferases unique to the type of wall made. Additionally, maize Golgi membranes enriched by flotation were separated further by free-flow electrophoresis (FFE), yielding 3009 proteins, of which 229 were known to function in cell wall synthesis or metabolism. A subset of proteins identified after flotation centrifugation were identified in Golgi membranes but failed to enrich in them. Individual classes of proteins associated with cell wall synthesis were asymmetrically distributed across the fractions of Golgi membranes separated by FFE.