POSTTRANSLATIONAL PROTEIN TRANSPORT INTO YEAST ER

该应用程序试图了解 翻译后跨内质膜转位 酿酒酵母网状结构。具体目标1涉及该机制 以底物为靶标。胞质伴侣蛋白的存在及其重要性 或者靶向分子将被评估。第二个具体目标将决定 信号序列对移位通道选通的作用。它 将检验这样的假设：信号序列取代了 易位素，结果，打开了易位通道。具体目标3 是确定转位基因各成分的化学计量学。 组成易位通道的3或4个Sec61P复合体的估计 都是基于电子显微照相技术制作的，这将是 经过生化检测。将测试Sec62p在催化组装中的作用。 最后，特定目标4试图了解鲁米纳热休克蛋白70在 易位过程。它将检验这种蛋白质作为一种 分子棘轮，而不是一个机器，“拉”蛋白质通过 薄膜。

The application seeks to understand the mechanism of posttranslational translocation across the membrane of the endoplasmic reticulum of Saccharomyces cerevisiae. Specific Aim 1 addresses the mechanism of targeting of substrates. The presence and importance of cytosolic chaperones or targeting molecules will be assessed. The second Specific Aim will determine the role of the signal sequence on the gating of the translocating channel. It will test the hypothesis that the signal sequence displaces a component of the translocon, and as a result, opens the translocation channel.. Specific Aim 3 is to determine the stoicheometry of the components of the translocon. Estimations of 3 or 4 Sec61p complexes comprising the translocation channel have been made based on electron micrographic techniques, and this will be tested biochemically. A role of Sec62p in catalyzing assembly will be tested. Finally, Specific Aim 4 seeks to understand the role of luminal Hsp70 in the translocation process. It will test the hypothesis that this protein works as a molecular ratchet rather than a machine that "pulls" the protein through the membrane.