THE RELATIONSHIP OF N-LINKED GLYCOSYLATION AND HEAVY-CHAIN BINDING-PROTEIN ASSOCIATION WITH THE SECRETION OF GLYCOPROTEINS
THE RELATIONSHIP OF N-LINKED GLYCOSYLATION AND HEAVY-CHAIN BINDING-PROTEIN ASSOCIATION WITH THE SECRETION OF GLYCOPROTEINS
复制标题
DOI：
10.1083/jcb.105.6.2665
复制
发表时间：
1987-12-01
影响因子：
7.8
通讯作者：
KAUFMAN, RJ
中科院分区：
文献类型：
--
作者：
DORNER, AJ;BOLE, DG;KAUFMAN, RJ
在中国仓鼠卵巢（CHO）细胞中研究了N-连接糖基化和与重链结合蛋白（BiP）结合与因子VIII（FVIII）、血管性血友病因子（vWF）和组织纤溶酶原激活剂（tPA）分泌的关系。FVIII具有含有20个成簇的潜在N-连接糖基化位点的高度糖基化区域。在与BiP的稳定复合物中检测到显著比例的FVIII，并且FVIII不分泌。严重糖基化区域的缺失导致与BiP的结合减少和更有效的分泌。衣霉素处理产生这种缺失形式的FVIII的细胞导致非糖基化的FVIII与BP的稳定缔合和有效分泌的抑制。vWF含有17个潜在的N-连接的糖基化位点，分散在整个分子中。vWF与BiP瞬时结合并有效分泌，表明CHO细胞能够分泌高度糖基化的蛋白质。tPA具有三个利用的N-连接糖基化位点，与BiP表现出低水平的结合，并被有效分泌。通过定点诱变或衣霉素处理破坏tPA的N-连接糖基化导致分泌水平降低和与BiP的关联增加。这种作用通过高水平的tPA表达而增强。糖基化状态和与BiP的结合程度可能与分泌效率相关。
The relationship of N-linked glycosylation and association with heavy chain binding protein (BiP) to the secretion of Factor VIII (FVIII), von Willebrand Factor (vWF), and tissue plasminogen activator (tPA) was studied in Chinese hamster ovary (CHO) cells. FVIII has a heavily glycosylated region containing 20 clustered potential N-linked gycosylation sites. A significant proportion of FVIII was detected in a stable complex with BiP and not secreted. Deletion of the heavily glycosylated region resulted in reduced association with BiP and more efficient secretion. Tunicamycin treatment of cells producing this deleted form of FVIII resulted in stable association of unglycosylatsed FVIII with BP and inhibition of efficient secretion. vWF contains 17 potential N-linked glycosylation sites scattered throughout the molecule. vWF was transiently associated with BiP and efficiently secreted demonstrating that CHO cells are competent to secrete a highly glycosylated protein. tPA, which has three utilized N-linked glycosylation sites,exhibited low level association with BiP and was efficiently secreted. Disruption of N-linked glycosylation of tPA by either site-directed mutagenesis or tunicamycin treatment resulted in reduced levels of secretion and increased association with BiP. This effect was enhanced by high levels of tPA expression. The glycosylation state and extent of association with BiP could be correlated with secretion efficiency.