US-Federal Republic of Germany Cooperative Research: The Effect of Monensin on Golgi Apparatus (Cell Biology)

该奖项支持D教授。普渡大学的詹姆斯·莫尔 与赫伯特斯普林博士和迈克尔博士合作研究 海德堡德国癌症研究所的Trendenlenburg博士说。 他们 计划测试目前的概念，如何钠选择性 离子载体莫能菌素通过特异性阻断高尔基体发挥作用 植物和动物细胞中的器官功能。 这是公认的 莫能菌素处理的细胞的电子显微照片显示放大， 高尔基池紊乱。 然而，有证据表明， 影响可能取决于细胞如何固定电子 显微镜 通过合作，他们将结合使用 最先进的光学和电子显微镜方法来观察 莫能菌素诱导活细胞中高尔基体的肿胀。 高 将采用压力冻结替代来比较图像 通过这种技术产生的透射电子显微镜， 用常规冷冻置换电子显微镜观察到的图像 显微镜 莫尔博士是最早使用莫能菌素进行研究的人之一 高尔基体的结构和功能。 德国 共同研究人员率先开发了 视频增强的观察方法和样品室设计， 计划中的实验。 此外，他们希望探索使用 激光扫描共聚焦显微镜，与E。 海德堡的Schnepf，它的开发者之一。 莫能菌素是一种钠离子载体，能够分解钠， 氢梯度 作为一种生物化学物质， 也是研究高尔基体功能的生物学研究工具 并确定亚细胞囊泡的分子途径， 交通 关于莫能菌素如何在活人体内起作用的一个完整假设 细胞是基于这样的假设，即transGolgi装置 莫能菌素治疗后脑池肿胀。 肿胀已经 在广泛的植物和动物细胞中观察到 莫能菌素并使用醛制备用于电子显微镜检查 固定剂 然而，肿胀的形态学证据较少或 与其他固定剂不存在。 拟议的研究将 批判性地评价莫能菌素肿胀的整体有效性 通过明确地确定高尔基体是否在 活细胞对莫能菌素的反应是肿胀。 合作 该计划还提供了一个测试德国激光器使用的机会 扫描共聚焦显微镜，一个非常新的，概念上令人兴奋的， 这是细胞生物学领域中极其昂贵的工具。 的 共焦扫描仪可能能够很好地实现分辨率 回答当前项目中提出的问题。 如果 所以这将是细胞生物学的一个重要的开创性的成就， 对涉及到各种各样的问题都有重要意义， 细胞内膜

This award supports Professor D. James Morre of Purdue University to collaborate in research with Drs. Herbert Spring and Michael Trendenlenburg of the German Cancer Institute in Heidelberg. They plan to test the current concepts of how the sodium-selective ionophore monensin exerts its action in specifically blocking Golgi apparatus function in plant and animal cells. It is well accepted that electron micrographs of monensin-treated cells display enlarged, disarrayed Golgi cisternae. However, there is evidence that these effects may be dependent on how the cells were fixed for electron microscopy. Through collaboration, they will use a combination of state-of-the-art light and electron microscopic approaches to observe monensin-induced swelling of Golgi apparatus in living cells. High pressure freeze substitution will be employed to compare images generated by this technique for transmission electron microscopy with images observed with conventional freeze substitution electron microscopy. Dr. Morre was among the first to use monensin in studies of Golgi apparatus structure and function. The German co-investigators have pioneered in the development of the video-enhanced viewing methods and sample chamber design needed for the planned experiments. In addition, they expect to explore the use of a laser-scanning confocal microscope, in collaboration with Dr. E. Schnepf of Heidelberg, one of its developers. Monensin is a sodium ionophore capable of collapsing sodium and hydrogen gradients. It has gained wide acceptance as a biochemical and biological investigative tool to study Golgi apparatus function and to identify the molecular pathways of subcellular vesicular traffic. An entire hypothesis of how monensin works in the living cell is based upon the assumption that trans Golgi apparatus cisternae swell following monensin treatment. Swelling has been observed in a wide range of plant and animal cells treated with monensin and prepared for electron microscopy using aldehyde fixatives. However, morphological evidence of swelling is less or nonexistent with other fixatives. The proposed research will critically evaluate the overall validity of the monensin-swelling hypothesis by determining unequivocally whether Golgi apparatus in the living cell respond to monensin by swelling. The collaborative plan also offers an opportunity to test the uses of a German laser scan confocal microscope, a very new, conceptually exciting and prohibitively expensive tool in the field of cell biology. The confocal scanner may well be able to achieve the resolving power necessary to answer the questions posed in the current project. If so, it will be an important pioneering achievement in cell biology, with significance for a broad variety of questions involving intracellular membranes.