Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe, 658-8558, Japan.
Glycoconj J. 2017 Dec;34(6):725-735. doi: 10.1007/s10719-016-9732-9. Epub 2016 Oct 6.
Sulfated glycosaminoglycan (GAG) chains are a class of long linear polysaccharides that are covalently attached to multiple core proteins to form proteoglycans (PGs). PGs are major pericellular and extracellular matrix components that surround virtually all mammalian cell surfaces, and create conducive microenvironments for a number of essential cellular events, such as cell adhesion, cell proliferation, differentiation, and cell fate decisions. The multifunctional properties of PGs are mostly mediated by their respective GAG moieties, including chondroitin sulfate (CS), heparan sulfate (HS), and keratan sulfate (KS) chains. Structural divergence of GAG chains is enzymatically generated and strictly regulated by the corresponding biosynthetic machineries, and is the major driving force for PG functions. Recent studies have revealed indispensable roles of GAG chains in stem cell biology and technology. In this review, we summarize the current understanding of GAG chain-mediated stem cell niches, focusing primarily on structural characteristics of GAG chains and their distinct regulatory functions in stem cell maintenance and fate decisions.
硫酸化糖胺聚糖（GAG）链是一类长线性多糖，通过共价键与多种核心蛋白结合形成蛋白聚糖（PGs）。PGs 是细胞外基质的主要成分，几乎围绕着所有哺乳动物细胞表面，并为许多重要的细胞事件创造有利的微环境，如细胞黏附、细胞增殖、分化和细胞命运决定。PGs 的多功能特性主要由其各自的 GAG 部分介导，包括软骨素硫酸盐（CS）、硫酸乙酰肝素（HS）和硫酸角质素（KS）链。GAG 链的结构差异是通过相应的生物合成机制酶促产生的，并受到严格调控，是 PG 功能的主要驱动力。最近的研究揭示了 GAG 链在干细胞生物学和技术中的不可或缺的作用。在这篇综述中，我们总结了目前对 GAG 链介导的干细胞生态位的理解，主要集中在 GAG 链的结构特征及其在干细胞维持和命运决定中的独特调节功能上。
