FUNCTION AND REGULATION OF INTERCELLULAR COMMUNICATION

细胞间通道允许直接交换离子和小分子 相邻细胞之间的分子。这些通道是由 连接蛋白是一个至少有13个基因的家族。连接蛋白基因的突变 与神经退行性疾病、耳聋、白内障和 心血管异常本提案的目标是确定 需要细胞间通讯的细胞或组织行为， 理解为什么需要连接蛋白之间的这种多样性。朝着这个 最后，我们建立了缺失3种不同连接蛋白基因的小鼠品系， Cx 37、Cx40和Cx 50。 建立缺乏Cx 37和Cx40的细胞系，以研究Cx 37和Cx40的作用。 在血管内皮中的通讯。出乎意料的是，Cx 37敲除 不孕是因为卵泡发育失败。CX 37淘汰赛也 显示血管异常，其中血管收缩的传播 在血管壁之间不会发生。为了理解这一现象，我们 将决定不同血管的亚细胞位置 连接蛋白，并测试我们的模型，只有Cx 37提供 内皮/平滑肌通讯，Cx40分析 击倒对手。 Cx 50和Cx46主要在眼透镜的纤维中表达 它们彼此高度偶联并与透镜上皮细胞高度偶联。 令人惊讶的是，敲除任何一个基因都会产生不透明，尽管失去了 Cx46导致老年性白内障，而Cx 50的缺失导致老年性白内障。 粉末型和透镜生长缺陷。为了了解如何失去 无论是连接蛋白导致白内障的形成，我们将绘制模式， 野生型和基因敲除动物中的透镜细胞通讯。以确定是否 问题来自沟通水平的变化或内在的 通道特性，我们将Cx46替换Cx 50编码区 产生靶向基因“敲入”。 之前，我们展示了非洲爪蟾在发育过程中失去交流 胚胎严重影响原肠胚形成。然而，各种相关的 有证据表明，沟通可以在更早的时候 模式化事件我们将通过扰动 在早期胚胎中使用反义消融和宿主通讯， 移植以产生缺乏母系遗传的Cx 38的胚胎。

Intercellular channels permit the direct exchange of ions and small molecules between adjacent cells. These channels are formed from connexins, a family of at least 13 genes. Mutations in connexin genes have been associated with neurodegenerative diseases, deafness, cataracts and cardiovascular abnormalities. The goals of this proposal are to identify the cell or tissue behaviors requiring intercellular communication and to understand why such diversity among connexins is required. Toward this end, we have created lines of mice missing 3 different connexin genes, Cx37, Cx40 and Cx50. Lines lacking Cx37 and Cx40 were created to study the role of communication in vascular endothelia. Unexpectedly, Cx37 knockouts are sterile because ovarian folliculogenesis fails. Cx37 knockouts also display a vascular abnormality in which propagation of vasoconstriction among the vessel wall does not occur. To understand this phenomenon, we will determine the subcellular location of the different vascular connexins in arterioles and test our model, that only Cx37 provides endothelial/smooth muscle communication, with an analysis of the Cx40 knockouts. Cx50 and Cx46 are expressed predominantly in the fibers of the ocular lens which are highly coupled to one another and to lens epithelial cells. Surprisingly, knockouts in either gene develop opacities although loss of Cx46 causes a senile-type cataract while loss of Cx50 leads to a pulverulent type and a lens growth defect. To understand how loss of either connexin leads to cataract formation, we will map the patterns of lens cell communication in wild-type and knockout animals. To determine if problems arise from changes in levels of communication or intrinsic channel properties we will replace the Cx50 coding region with Cx46 creating a targeted gene 'knock-in'. Previously, we showed that loss of communication in the developing Xenopus embryos critically affects gastrulation. However, a variety of correlative evidence suggests that communication could influence much earlier patterning events. We will test this hypothesis by perturbing communication in the early embryos using anti-sense ablation and host- transfer to generate embryos lacking maternally inherited Cx38.