GLUCOSAMINE INOSITOLPHOSPHORYLCERAMIDE TRANSFERASE1 (GINT1) Is a GlcNAc-Containing Glycosylinositol Phosphorylceramide Glycosyltransferase

Journal Article · Mon May 14 00:00:00 EDT 2018 · Plant Physiology (Bethesda)

DOI:https://doi.org/10.1104/pp.18.00396· OSTI ID:1437090

Ishikawa, Toshiki  ^[1]; Fang, Lin  ^[2]; Rennie, Emilie A.  ^[3]; Sechet, Julien  ^[2]; Yan, Jingwei  ^[2]; Jing, Beibei  ^[2]; Moore, William  ^[4]; Cahoon, Edgar B.  ^[5]; Scheller, Henrik V.  ^[4]; Kawai-Yamada, Maki  ^[1]; Mortimer, Jenny C.  ^[2]

---

1. Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
2. Joint BioEnergy Institute, Emeryville, California 94608, Biosciences Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720
3. Biosciences Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Plant and Molecular Biology, University of California, Berkeley, California 94720, Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588
4. Joint BioEnergy Institute, Emeryville, California 94608, Biosciences Area, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Plant and Molecular Biology, University of California, Berkeley, California 94720
5. Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588

Glycosylinositol phosphorylceramides (GIPCs), which have a ceramide core linked to a glycan headgroup of varying structure, are the major sphingolipids in the plant plasma membrane. Recently, we identified the major biosynthetic genes for GIPC glycosylation in Arabidopsis thaliana, and demonstrated that the glycan headgroup is essential for plant viability. However, the function of GIPCs and the significance of their structural variation are poorly understood. Here, we characterized the Arabidopsis glycosyltransferase GLUCOSAMINE INOSITOLPHOSPHORYLCERAMIDE TRANSFERASE1 (GINT1) and showed that it is responsible for the glycosylation of a subgroup of GIPCs found in seeds and pollen that contain N-acetylglucosamine (GlcNAc) and glucosamine (GlcN; collectively GlcN(Ac)). In Arabidopsis gint1 plants, loss of the GlcN(Ac) GIPCs did not affect vegetative growth, although seed germination was less sensitive to abiotic stress than in wild-type plants. However, in rice, where GlcN(Ac) containing GIPCs are the major GIPC subgroup in vegetative tissue, loss of GINT1 was seedling lethal. Furthermore, we could produce, de novo, "rice-like" GlcN(Ac) GIPCs in Arabidopsis leaves, which allowed us to test the function of different sugars in the GIPC headgroup. Lastly, this study describes a monocot GIPC biosynthetic enzyme and shows that its Arabidopsis homolog has the same biochemical function. We also identify a possible role for GIPCs in maintaining cell-cell adhesion.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER); National Science Foundation (NSF)
• Grant/Contract Number: AC02-05CH11231; 17K15411; 26292190; 1158500
• OSTI ID: 1437090
• Alternate ID(s): OSTI ID: 1457008
• Journal Information: Plant Physiology (Bethesda), Journal Name: Plant Physiology (Bethesda) Vol. 177 Journal Issue: 3; ISSN 0032-0889
• Publisher: Oxford University Press
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES