A POSTTARGETING SIGNAL SEQUENCE RECOGNITION EVENT IN THE ENDOPLASMIC-RETICULUM MEMBRANE
A POSTTARGETING SIGNAL SEQUENCE RECOGNITION EVENT IN THE ENDOPLASMIC-RETICULUM MEMBRANE
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DOI：
10.1016/0092-8674(95)90313-5
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发表时间：
1995-07-28
期刊：
影响因子：
64.5
通讯作者：
RAPOPORT, TA
中科院分区：
文献类型：
--
作者：
JUNGNICKEL, B;RAPOPORT, TA
我们已经分析了早期阶段的共翻译运输的分泌蛋白催乳素通过哺乳动物内质网（ER）膜。在胞质溶胶中新生多肽链的信号序列被SRP识别后，该链被转移到膜中，在膜中发生第二信号序列识别步骤，对于该步骤，Sec 61 p复合物在脂质双层中的存在是必需的和足够的。这一步骤导致核糖体-新生链复合物和Sec 61 p复合物之间的紧密连接，并导致新生链有效插入易位位点。这些结果表明，易位底物在被允许穿过ER膜之前经历两次识别事件。
We have analyzed early phases of the cotranslational transport of the secretory protein preprolactin through the mammalian endoplasmic reticulum (ER) membrane. Following recognition of the signal sequence of the nascent polypeptide chain in the cytosol by the SRP, the chain is transferred into the membrane, where a second signal sequence recognition step takes place for which the presence in the lipid bilayer of the Sec61p complex is essential and sufficient. This step leads to a tight junction between the ribosome-nascent chain complex and the Sec61p complex, and to the productive insertion of the nascent chain into the translocation site, These results show that a translocation substrate is subjected to two recognition events before being allowed to cross the ER membrane.