The Arabidopsis Golgi-localized GDP-L-fucose transporter is required for plant development.

Carsten Rautengarten,Lifeng Liu,Berit Ebert,Markus Pauly,Solomon Stonebloom,Henrik Vibe Scheller,Andreia M Smith-Moritz,Ariel Orellana,Joshua L Heazlewood

doi:10.1038/ncomms12119

Abstract

Nucleotide sugar transport across Golgi membranes is essential for the luminal biosynthesis of glycan structures. Here we identify GDP-fucose transporter 1 (GFT1), an Arabidopsis nucleotide sugar transporter that translocates GDP-L-fucose into the Golgi lumen. Using proteo-liposome-based transport assays, we show that GFT preferentially transports GDP-L-fucose over other nucleotide sugars in vitro, while GFT1-silenced plants are almost devoid of L-fucose in cell wall-derived xyloglucan and rhamnogalacturonan II. Furthermore, these lines display reduced L-fucose content in N-glycan structures accompanied by severe developmental growth defects. We conclude that GFT1 is the major nucleotide sugar transporter for import of GDP-L-fucose into the Golgi and is required for proper plant growth and development.

Highlights

Nucleotide sugar transport across Golgi membranes is essential for the luminal biosynthesis of glycan structures
This study identifies and biochemically characterizes an Arabidopsis Golgi-localized GDP-Fuc transporter (AT5G19980), previously named GONST4 according to its homology to other GDP sugar transporters
We show that GONST4 transports GDP-Fuc and not GDP-Man, and our in vivo analysis supports its role as the primary Golgi GDP-Fuc transporter

Summary

Introduction

Nucleotide sugar transport across Golgi membranes is essential for the luminal biosynthesis of glycan structures. Using proteo-liposome-based transport assays, we show that GFT preferentially transports GDP-L-fucose over other nucleotide sugars in vitro, while GFT1-silenced plants are almost devoid of L-fucose in cell wall-derived xyloglucan and rhamnogalacturonan II. These lines display reduced L-fucose content in N-glycan structures accompanied by severe developmental growth defects. The initial stages of the plant secretory system include the endoplasmic reticulum (ER) and the Golgi apparatus These compartments are essential for the biosynthesis of non-cellulosic cell wall polysaccharides, and the glycosylation of proteins and lipids. This study identifies and biochemically characterizes an Arabidopsis Golgi-localized GDP-Fuc transporter (AT5G19980), previously named GONST4 according to its homology to other GDP sugar transporters. Due to this newly attributed function, we have revised its name to GDP-fucose transporter 1 (GFT1)

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