Tatara Yota, Kakizaki Ikuko, Suto Shinichiro, Ishioka Haruna, Negishi Mika, Endo Masahiko
Department of Glycotechnology, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan Department of Glycobiomedicine, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
Department of Glycotechnology, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan Department of Glycobiomedicine, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan.
Glycobiology. 2015 May;25(5):557-69. doi: 10.1093/glycob/cwu186. Epub 2014 Dec 22.
Epiphycan (EPY) from salmon nasal cartilage has a glycosaminoglycan (GAG) domain that is heavily modified by chondroitin 4-sulfate and chondroitin 6-sulfate. The functional role of the GAG domain has not been investigated. The interaction of EPY with collagen was examined in vitro using surface plasmon resonance analysis. EPY was found to bind to type I collagen via clustered chondroitin sulfate (CS), while a single chain of CS was unable to bind. Types I, III, VII, VIII and X collagen showed high binding affinity with EPY, whereas types II, IV, V, VI and IX showed low binding affinities. Chemical modification of lysine residues in collagen decreased the affinity with the clustered CS. These results suggest that lysine residues of collagen are involved in the interaction with the clustered CS, and the difference in lysine modification defines the binding affinity to EPY. The clustered CS was also involved in an inter-saccharide interaction, and formed self-associated EPY. CS of EPY promoted fibril formation of type I collagen.
来自鲑鱼鼻软骨的表皮黏蛋白（EPY）具有一个糖胺聚糖（GAG）结构域，该结构域被硫酸软骨素4和硫酸软骨素6高度修饰。GAG结构域的功能作用尚未得到研究。使用表面等离子体共振分析在体外检测了EPY与胶原蛋白的相互作用。发现EPY通过聚集的硫酸软骨素（CS）与I型胶原蛋白结合，而单链CS无法结合。I型、III型、VII型、VIII型和X型胶原蛋白与EPY表现出高结合亲和力，而II型、IV型、V型、VI型和IX型则表现出低结合亲和力。胶原蛋白中赖氨酸残基的化学修饰降低了与聚集CS的亲和力。这些结果表明，胶原蛋白的赖氨酸残基参与了与聚集CS的相互作用，赖氨酸修饰的差异决定了对EPY的结合亲和力。聚集的CS还参与了糖间相互作用，并形成了自我缔合的EPY。EPY的CS促进了I型胶原蛋白的原纤维形成。
