剖析了高尔基体和脂质筏在胆固醇向细胞表面的生物合成转运中的作用。,Proceedings
剖析了高尔基体和脂质筏在胆固醇向细胞表面的生物合成转运中的作用。
Proceedings of the National Academy of Sciences of the United States of America
(
IF
9.4
)
Pub Date : 2000-07-18
, DOI:
10.1073/pnas.140218797
S Heino
1
,
S Lusa
,
P Somerharju
,
C Ehnholm
,
V M Olkkonen
,
E Ikonen
Affiliation
Department of Biochemistry, National Public Health Institute, Mannerheimintie 166, 00300 Helsinki, Finland.
在这项研究中，地毯清洗13825404095我们比较了新合成的胆固醇与流感病毒血凝素（HA）从内质网到质膜的转运。通过去除环糊精来监测胆固醇在细胞表面上的到达，并且通过表面胰蛋白酶消化和内切糖苷酶H消化来监测HA的转运。我们发现布雷菲德菌素A处理高尔基复合体的拆卸导致胆固醇运输的部分抑制，同时完全阻止HA的运输。此外，诺考达唑使微管解聚在相似程度上抑制了胆固醇和HA的转运。分析胆固醇在脂筏中的分配后，我们发现新合成的胆固醇在合成后开始迅速与低密度耐洗涤剂膜结合，在细胞表面被检测到之前，它的筏联在追逐时进一步增加。当在15°C的温育条件下阻止胆固醇的运输时，新合成的胆固醇与低密度去污剂不溶性膜的结合减少，胆固醇堆积在中等密度的馏分中。我们的结果为高尔基复合体对新合成的胆固醇向细胞表面转运的部分贡献提供了证据，并表明耐洗涤剂的膜参与了该过程。降低了新合成的胆固醇与低密度去污剂不溶性膜的结合，胆固醇以中等密度的一部分积累。我们的结果为高尔基复合体对新合成的胆固醇向细胞表面转运的部分贡献提供了证据，并表明耐洗涤剂的膜参与了该过程。降低了新合成的胆固醇与低密度去污剂不溶性膜的结合，胆固醇以中等密度的一部分积累。我们的结果为高尔基复合体对新合成的胆固醇向细胞表面转运的部分贡献提供了证据，并表明耐洗涤剂的膜参与了该过程。
"点击查看英文标题和摘要"
Dissecting the role of the golgi complex and lipid rafts in biosynthetic transport of cholesterol to the cell surface.
In this study, we compared the transport of newly synthesized cholesterol with that of influenza virus hemagglutinin (HA) from the endoplasmic reticulum to the plasma membrane. The arrival of cholesterol on the cell surface was monitored by cyclodextrin removal, and HA transport was monitored by surface trypsinization and endoglycosidase H digestion. We found that disassembly of the Golgi complex by brefeldin A treatment resulted in partial inhibition of cholesterol transport while completely blocking HA transport. Further, microtubule depolymerization by nocodazole inhibited cholesterol and HA transport to a similar extent. When the partitioning of cholesterol into lipid rafts was analyzed, we found that newly synthesized cholesterol began to associate with low-density detergent-resistant membranes rapidly after synthesis, before it was detectable on the cell surface, and its raft association increased further upon chasing. When cholesterol transport was blocked by using 15 degrees C incubation, the association of newly synthesized cholesterol with low-density detergent-insoluble membranes was decreased and cholesterol accumulated in a fraction with intermediate density. Our results provide evidence for the partial contribution of the Golgi complex to the transport of newly synthesized cholesterol to the cell surface and suggest that detergent-resistant membranes are involved in the process.