Enrichment of hydroxylated C24- and C26-acyl-chain sphingolipids mediates PIN2 apical sorting at trans-Golgi network subdomains

作者：Valérie Wattelet‐Boyer, Lysiane Brocard, Kristoffer Jonsson, Nicolas Esnay, Jérôme Joubès, Frédéric Domergue, Sébastien Mongrand, Natasha V. Raikhel, Rishikesh P. Bhalerao, Patrick Moreau, Yohann Boutté · 发表于：Nature Communications · 年份：2016 · DOI：10.1038/ncomms12788 · 被引用次数：93 · 研究领域：Plant Molecular Biology Research、Photosynthetic Processes and Mechanisms、Cellular transport and secretion

The post-Golgi compartment trans-Golgi Network (TGN) is a central hub divided into multiple subdomains hosting distinct trafficking pathways, including polar delivery to apical membrane. Lipids such as sphingolipids and sterols have been implicated in polar trafficking from the TGN but the underlying mechanisms linking lipid composition to functional polar sorting at TGN subdomains remain unknown. Here we demonstrate that sphingolipids with α-hydroxylated acyl-chains of at least 24 carbon atoms are enriched in secretory vesicle subdomains of the TGN and are critical for de novo polar secretory sorting of the auxin carrier PIN2 to apical membrane of Arabidopsis root epithelial cells. We show that sphingolipid acyl-chain length influences the morphology and interconnections of TGN-associated secretory vesicles. Our results uncover that the sphingolipids acyl-chain length links lipid composition of TGN subdomains with polar secretory trafficking of PIN2 to apical membrane of polarized epithelial cells.