Molecular Glycobiology, Research Team for Mechanism of Aging, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Itabashi-ku, Tokyo, Japan.
Structural Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki, Japan.
Methods Mol Biol. 2020;2132:609-619. doi: 10.1007/978-1-0716-0430-4_52.
Protein O-mannose β1,2-N-acetylglucosaminyltransferase 1 (POMGNT1) is one of the gene products responsible for α-dystroglycanopathy, which is a type of congenital muscular dystrophy caused by O-mannosyl glycan defects. The originally identified function of POMGNT1 was as a glycosyltransferase that catalyzes the formation of the GlcNAcβ1-2Man linkage of O-mannosyl glycan, but the enzyme function is not essential for α-dystroglycanopathy pathogenesis. Our recent study revealed that the stem domain of POMGNT1 has a carbohydrate-binding ability, which recognizes the GalNAcβ1-3GlcNAc structure. This carbohydrate-binding activity is required for the formation of the ribitol phosphate (RboP)-3GalNAcβ1-3GlcNAc structure by fukutin. This protocol describes methods to assess the carbohydrate-binding activity of the POMGNT1 stem domain.
蛋白 O-甘露糖β1,2-N-乙酰氨基葡萄糖基转移酶 1（POMGNT1）是导致α- 聚糖缺陷型先天性肌营养不良症的基因产物之一。POMGNT1 的最初鉴定功能是作为糖基转移酶，催化 O-甘露糖聚糖中 GlcNAcβ1-2Man 键的形成，但该酶功能对于 α-聚糖缺陷型先天性肌营养不良症的发病机制并非必需。我们最近的研究表明，POMGNT1 的茎域具有碳水化合物结合能力，可识别 GalNAcβ1-3GlcNAc 结构。这种碳水化合物结合活性是 fukutin 形成 RboP-3GalNAcβ1-3GlcNAc 结构所必需的。本方案描述了评估 POMGNT1 茎域碳水化合物结合活性的方法。
