MEMBRANE BIOGENESIS AND MEMBRANE FUSION

这个建议的目的是继续研究我们的两个方面 膜生物学领域的最新发现。第一，是 整合膜蛋白自发插入预制双层 第二种是由同样的酶催化的膜融合 方法论。我们观察到，杂质的存在 预先形成的囊泡的双层触发了纯化的 完整膜蛋白与单层膜的融合 当磷脂处于凝胶状态时，蛋白质脂质体。The Rapid 通过这种操作脂质体和蛋白脂质体的融合 磷脂双层膜是一种理想的模型体系。 磷脂双层水平的细胞膜融合。我们 建议利用该系统研究膜中的几个概念 生物学的同时，我们扩展了这种方法用于重建的适用性 学习。我们计划用几种不同的方法构建蛋白质脂质体 膜蛋白通过这个过程；一些完整的膜蛋白 在这项研究中，将被选为演示功能交互作用 在新形成的膜内，而其他膜将被用来修饰 蛋白质脂质体的表面可利用性和特性。作为一名 由于这方面的工作，我们预计能够构建一个 由几种不同的整体膜组成的模型细胞膜 蛋白质中的许多当前的概念在细胞和膜 生物学是可以检验的。此外，明显的构建能力 通过这个过程，细胞尺寸的蛋白质脂质体(7微米)将被 进一步研究，以努力设计和构建一个模型细胞 预先确定的蛋白质组成和脂肪/蛋白质比例。稳定性 在这些极大的高脂/蛋白比的蛋白质脂质体中 超出了我们的预期，我们相信所提出的蛋白质脂质体 低脂蛋白比将提供非常稳定的囊泡，这可能 表示理想的模型单元格。长期目标是双重的，包括 尊重我们所发现的现象。我们建议确定 无论我们结合整体膜的机制 蛋白进入预制的双层代表体内的参与 细胞膜中的磷脂。我们还将确定是否 调节生物膜间膜融合的特异性 部分是由于所提出的蛋白质脂质体融合的机制。 程序。

The object of this proposal is to continue the study of two aspects of our recent discovery in the field of membrane biology. The first, is the spontaneous insertion of integral membrane proteins into preformed bilayers and the second is the membrane fusion that is catalyzed by the same methodology. We have observed that the presence of impurities in the bilayer of preformed vesicles triggers both the incorporation of purified integral membrane proteins as well as the fusion of unilamellar proteoliposomes when the phospholipids are in the gel state. The rapid fusion of liposomes and proteoliposomes by this manipulation of the phospholipid bilayer presents an ideal model system for the study of the cellular membrane fusion at the level of the phospholipid bilayer. We propose to utilize this system to investigate several concepts in membrane biology while we extend the applicability of this method for reconstruction studies. We plan to construct proteoliposomes with several different membrane proteins by this procedure; some of the integral membrane proteins for this study will be selected to demonstrate a functional interaction within the newly formed membrane while others will be employed to modify the surface availability and characteristics of the proteoliposome. As a result of this aspect of the work, we expect to be able to construct a model cell membrane composed of several different integral membrane proteins in which many of the current concepts in cellular and membrane biology can be tested. Furthermore, the apparent ability to construct proteoliposomes of cellular dimension (7 microns) by this procedure will be further examined in an effort to design and construct a model cell of predetermined protein composition and lipid/protein ratio. The stability of these very large proteoliposomes of high lipid/protein ratio has exceeded our expectations and we believe that the proposed proteoliposomes of low lipid-to-protein ratio will provide a very stable vesicle which may represent the ideal model cell. The long range goals are two-fold with respect to the phenomenon we have discovered. We propose to determine whether the mechanism by which we have incorporated integral membrane proteins into preformed bilayers represents the in vivo participation of the phospholipid in cellular membranes. We will determine too whether the specificity of membrane fusion among biological membrane is regulated in part by the proposed mechanism for the fusion of proteoliposomes in this procedure.