PHYSIOLOGY OF RECONSTITUTED CONNEXIN CHANNELS

间隙结通道形成动态调节的水通道，该水通道 调节细胞间离子和小分子的直接转移。这个 通道由两个完整的膜结构(每个在一个等离子体中)组成 膜)由连接蛋白形成。细胞间通信 由连接通道介导的信号被认为对正常 许多组织的发育和成熟的功能。这些频道是 对所有已知的细胞质第二信使都是可渗透的。因此， 有关渠道如何运作、如何选通以及执行哪些操作的信息 通过它，以及如何调节这些特性是医学上的， 生物学和生物物理学的重要性。 缝隙结沟道很难现场研究，因为它是 实验技术和操作通常不能接触到 应用于其他通道-通道的两端都在单元格内部。 进入毛孔的途径是通过细胞质，所以很难区分 直接作用于渠道的因素，而不是通过 中间细胞成分。 这项建议的长期目标是理解生理学 和生物；缝隙结沟道的物理。方法是 将通道形成结构结合到单一磷脂中 可以研究其性能的膜。这项建议是为了研究 连接蛋白32形成的离子通道，形成缝隙连接通道 活体细胞之间的相互作用。 具体地说，建议(1)描述和探索渗透， 单磷脂中连接蛋白32通道的门控和调制 双分子层，(2)探讨蛋白激酶的磷酸化对细胞周期的影响 连接蛋白32通道的特性，以及(3)功能角色的探讨 连接蛋白分子的特定区域。 通过实验研究缝隙连接蛋白通道的生理学 可及性系统，人们希望了解蛋白质的调节 负责协调交界处的交流。通过缝隙连接方式的耦合是 如此广泛，对这一过程的阐明无疑将 对细胞和发育生物学的许多领域产生深远影响。

The gap junction channel forms a dynamically regulated aqueous pathway that mediates direct transfer of ions and small molecules between cells. The channel is composed of two integral membrane structures (each in one plasma membrane) formed of connexin protein. The intercellular communication mediated by junctional channels is considered crucial for normal development and mature function of many tissues. The channels are permeable to all known cytoplasmic second messengers. Therefore, information about how the channel functions, how it is gated, what goes through it, and how these properties can be modulated is of medical, biological and biophysical importance. The gap junction channel is difficult to study in situ because it is inaccessible for the experimental techniques and manipulations commonly applied to other channels - both ends of the channel are inside of cells. Access to the pore is via cytoplasm, so it is difficult to distinguish factors that act directly on the channel from those that act on it via intermediate cellular components. The long-term objective of this proposal is to understand the physiology and bio;physics of the gap junction channel. the approach is to incorporate the channel-forming structure into single phospholipid membranes where its properties can be studied. This proposal is to study the ion channels formed by connexin32, which forms gap junction channels between cells in vivo. Specifically, it is proposed to (1) describe and explore the permeation, gating and modulation of connexin32 channels in single phospholipid bilayers, (2) explore the effects of phosphorylation by protein kinases on the properties of connexin32 channels, and (3) explore the functional roles of specific domains of the connexin molecules. By studying the physiology of connexin channels in an experimentally accessible system, one hopes to understand the regulation of the protein that mediates junctional communication. Coupling by way of gap junction is so widespread that elucidation of this process will undoubtedly have profound effects in many areas of cellular and developmental biology.