Vesicular and non-vesicular transport feed distinct glycosylation pathways in the Golgi

Publication year: 2013
Authors: D'Angelo G. 1, Uemura T., Chuang C.C., Polishchuk E., Santoro M., Ohvo-Rekilä H., Sato T., Di Tullio G., Varriale A., D'Auria S., Daniele T., Capuani F., Johannes L., Mattjus P., Monti M., Pucci P., Williams R.L., Burke J.E., Platt F.M., Harada A., De Matteis M.A.
Affiliations:

1 - Telethon Institute of Genetics and Medicine, Via Pietro Castellino 111, 80131 Naples, Italy

Published in: Nature Research Letter, 2013, Vol. 501, p. 7465
doi: 10.1038/nature12423

Newly synthesized proteins and lipids are transported across the Golgi complex via different mechanisms whose respective roles are not completely clear. We previously identified a non-vesicular intra-Golgi transport pathway for glucosylceramide (GlcCer)—the common precursor of the different series of glycosphingolipids—that isoperated by the cytosolic GlcCer-transfer protein FAPP2 (also known as PLEKHA8). However, the molecular determinants of the FAPP2-mediated transfer of GlcCer from the cis-Golgi to the trans-Golgi network, as well as the physiological relevance of maintaining two parallel transport pathways of GlcCer—vesicular and non-vesicular—through the Golgi, remain poorly defined. Here, using mouse and cell models, we clarify the molecular mechanisms underlying the intra-Golgi vectorial transfer of GlcCer by FAPP2 and show that GlcCer is channelled by vesicular and non-vesicular transport to two topologically distinct glycosylation tracks in the Golgi cis ternae and the trans-Golgi network, respectively. Our results indicate that the transport modality across the Golgi complex is a key determinant for the glycosylation pattern of a cargo and establish a new paradigm for the branching of the glycosphingolipid synthetic pathway.


MP-SPR keywords: binding, Golgi, liposomes, transport