The United Graduate School of Agricultural Science, Gifu University, Japan.
Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan.
FEBS Lett. 2023 Dec;597(24):3102-3113. doi: 10.1002/1873-3468.14775. Epub 2023 Nov 27.
N-acetylglucosaminyltransferase-V (GnT-V or MGAT5) is a glycosyltransferase involved in cancer metastasis that creates the β1,6-branch on N-glycans of target proteins such as cell adhesion molecules and cell surface receptors. The 3D structure of GnT-V and its catalytic site, which are critical for the interaction with the N-glycan terminal, have already been revealed. However, it remains unclear how GnT-V recognizes the core part of N-glycan or the polypeptide part of the acceptor. Using molecular dynamics simulations and biochemical experiments, we found that several residues outside the catalytic pocket are likely involved in the recognition of the core part of N-glycan. Furthermore, our simulation suggested that UDP binding affects the orientation of the acceptor due to the conformational change at the Manα1,6-Man linkage. These findings provide new insights into how GnT-V recognizes its glycoprotein substrates.
N-乙酰氨基葡萄糖基转移酶-V（GnT-V 或 MGAT5）是一种参与癌症转移的糖基转移酶，它在靶蛋白（如细胞黏附分子和细胞表面受体）的 N-聚糖上创建β1,6-分支。GnT-V 的 3D 结构及其催化位点对于与 N-聚糖末端的相互作用至关重要，已经被揭示。然而，GnT-V 如何识别 N-聚糖的核心部分或受体的多肽部分仍不清楚。使用分子动力学模拟和生化实验，我们发现催化口袋外的几个残基可能参与了 N-聚糖核心部分的识别。此外，我们的模拟表明，由于 Manα1,6-Man 键的构象变化，UDP 结合会影响受体的取向。这些发现为 GnT-V 如何识别其糖蛋白底物提供了新的见解。
