Cellular heparan sulfate participates in the metabolism of prions
Cellular heparan sulfate participates in the metabolism of prions
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DOI：
10.1074/jbc.m301152200
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发表时间：
2003-10-10
影响因子：
4.8
通讯作者：
Taraboulos, A
中科院分区：
文献类型：
--
作者：
Ben-Zaken, O;Tzaban, S;Taraboulos, A
在朊病毒疾病期间，宿主蛋白PrPC被重新折叠成异常的“朊病毒”PrPSc。组织学和药理学资料表明，糖胺聚糖可能参与朊病毒疾病的发展。在这里，我们提出了第一个直接证据，证明细胞糖胺聚糖在朊病毒感染的ScN2a细胞中PrPSc的生物发生中发挥作用。当ScN2a细胞与雌二醇β - d -木糖苷孵育以抑制蛋白聚糖的糖基化时，PrPSc大幅降低。用肝素酶III处理ScN2a-M细胞，而不是用肝素酶I或软骨素酶ABC，导致PrPSc的显著减少。相比之下，通过免疫荧光显微镜和浮选程序检测，PrPC的数量及其亚细胞分布均未受到影响。在中性或酸性pH下用肝素酶III体外处理ScN2a膜均未降低蛋白酶抗性PrPSc的水平。硫酸酸化抑制剂氯酸钠可大大降低ScN2a细胞中的PrPSc (Gabizon， R., Meiner， Z., Halimi， M., and Ben-Sasson， S. A.（1993）。物理学报。157,319-325)。可溶性硫酸肝素和硫酸软骨素都能部分恢复氯酸处理细胞中PrPSc的水平。我们得出结论，肝素酶iii敏感的（可能是低硫化的）细胞硫酸肝素在ScN2a细胞中PrPSc的生物发生中起重要作用。
During prion diseases, the host protein PrPC is refolded into an abnormal conformer "prion" PrPSc. Histological and pharmacological data have suggested that glycosaminoglycans may be involved in the development of prion diseases. Here we present the first direct evidence that cellular glycosaminoglycans play a role in the biogenesis of PrPSc in prion-infected ScN2a cells. When ScN2a cells were incubated with estradiol beta-D-xyloside to inhibit the glycosylation of proteoglycans, PrPSc was vastly reduced. Treating ScN2a-M cells with heparinase III, but not with heparinase I or chondroitinase ABC, caused a profound reduction of PrPSc. In contrast, neither the amount of PrPC nor its subcellular distribution were affected as assayed by immunofluorescence microscopy and flotation procedures. In vitro treatment of ScN2a membranes with heparinase III at either neutral or acidic pH did not reduce the level of protease-resistant PrPSc. The inhibitor of sulfation, sodium chlorate, vastly reduces PrPSc in ScN2a cells (Gabizon, R., Meiner, Z., Halimi, M., and Ben-Sasson, S. A. ( 1993) J. Cell. Physiol. 157, 319-325). Both soluble heparan sulfate and chondroitin sulfate partially restored the level of PrPSc in chlorate-treated cells. We conclude that heparinase III-sensitive, presumably undersulfated, cellular heparan sulfate plays a significant role in the biogenesis of PrPSc in ScN2a cells.