Division of Cancer Chemotherapy, Miyagi Cancer Center Research Institute, Natori, Japan.
Faculty of Health and Medical Care, Saitama Medical University, Moroyama, Saitama, Japan.
Glycoconj J. 2022 Oct;39(5):677-683. doi: 10.1007/s10719-022-10067-7. Epub 2022 Jun 8.
Sialidases (EC 3.2.1.18, also called neuraminidases) catalyze the removal of α-glycosidically linked sialic acid residues from glycoproteins and glycolipids; this is the initial step in the degradation of these glycoconjugates. Sialidases of mammalian origin have been implicated in not only lysosomal catabolism but also the modulation of functional molecules involved in many biological processes. To date, four types of mammalian sialidases have been cloned and designated as Neu1, Neu2, Neu3 and Neu4. These sialidases differ in their subcellular localization and enzymatic properties, as well as their chromosomal localization, and they are expressed in a tissue-specific manner. Among the sialidases, the plasma membrane-associated sialidase Neu3 appears to play particular roles in controlling transmembrane signaling through the modulation of gangliosides, and its aberrant expression is closely related to various pathogeneses, including that of cancer. Interestingly, the human orthologue NEU3 acts in two ways, catalytic hydrolysis of gangliosides and protein interactions with other signaling molecules. Aberrant NEU3 expression can induce various pathological conditions. This review briefly summarizes recent studies, focusing on the involvement of NEU3 in various pathological phenomena.
唾液酸酶（EC 3.2.1.18，也称为神经氨酸酶）催化糖蛋白和糖脂中α-糖苷键连接的唾液酸残基的去除；这是这些糖缀合物降解的初始步骤。哺乳动物来源的唾液酸酶不仅与溶酶体代谢有关，而且与参与许多生物过程的功能分子的调节有关。迄今为止，已经克隆并命名了四种类型的哺乳动物唾液酸酶，分别为 Neu1、Neu2、Neu3 和 Neu4。这些唾液酸酶在亚细胞定位、酶学特性以及染色体定位方面存在差异，并且以组织特异性方式表达。在这些唾液酸酶中，与质膜相关的唾液酸酶 Neu3 似乎通过调节神经节苷脂在控制跨膜信号转导中发挥特殊作用，其异常表达与各种发病机制密切相关，包括癌症。有趣的是，人同源物 NEU3 以两种方式起作用，即神经节苷脂的催化水解和与其他信号分子的蛋白相互作用。异常的 NEU3 表达可诱导各种病理状况。本文简要总结了最近的研究，重点介绍了 NEU3 在各种病理现象中的作用。
