N-acetylglucosamine modification in the lumen of the endoplasmic reticulum

作者：Ogawa Mitsutaka; Sawaguchi Shogo; Furukawa Koichi; Okajima Tetsuya^*

来源：Biochimica et Biophysica Acta-General Subjects, 2015, 1850(6): 1319-1324.

DOI：10.1016/j.bbagen.2015.03.003

• Notch
• EOGT
• O-GlcNAc
• UDP-GlcNAc transporter
• alpha-Dystroglycan
• GTDC2

Background: O-linked beta-N-acetylglucosamine (O-GlcNAc) modification of epidermal growth factor (EGF) domains catalyzed by EGF domain O-GlcNAc transferase (EOGT) is the first example of GlcNAc modification in the lumen of the endoplasmic reticulum (ER).
Scope of review: This review summarizes current knowledge on the EOGT-catalyzed O-GlcNAc modification of EGF domains obtained through biochemical characterization, genetic analysis in Drosophila, and identification of human EOGT mutation. Additionally, this review discusses GTDC2 another ER protein homologous to EOGT that catalyzes the GlcNAc modification of O-mannosylated alpha-dystroglycan and other components of the bio-synthetic pathway involved in GlcNAc modification in the ER lumen.
Major conclusions: GlcNAc modification in the ER lumen has been identified as a novel type of protein modification that regulates specific protein function. Moreover, abnormal GlcNAc modification in the ER lumen is responsible for Adams-Oliver syndrome and Walker-Warburg syndrome.
General significance: Elucidation of the biological function of GlcNAc modification in the ER lumen will provide new insights into the unique roles of O-glycans, whose importance has been demonstrated in multifunctional glycoproteins such as Notch receptors and alpha-dystroglyan.

• 出版日期2015-6