IVEM TOMOGRAPHY OF CUBIC MEMBRANES IN CHAOS CAROLINSIS MITOCHONDRIA

(由美国国家科学基金会DMB 8916315至C.A.曼内拉支持)立方膜 是对称的周期性结构，出现在各种各样的 生命系统。晶体结构有几种变化 建议用于不同生物中观察到的膜阵列 系统。在以前的工作中(邓等人原生动物学，在印中)，一个 开发了模板匹配法来间接识别 结晶型，用电子显微镜观察阿米巴线粒体。在……里面 在这项工作中，我们从IVEM断层扫描中确定了晶体类型 重建，与计算机生成的模型体积 一种合适类型的完美水晶。这验证了 模板匹配法。我们对线粒体进行了重建 表示两种不同晶体类型的示例， 双钻石和陀螺仪。计算机的广泛使用 可视化和建模方法使我们不仅能够确定 晶体类型，也要了解立方膜是如何 整合到线粒体的架构中，提供洞察力 进入他们的功能。在这两个例子中，立方体中的空间 显示的区域是晶状体内间隙，它连接到 线粒体膜内外之间的间隙由小管构成 连接的区域，就像我们在其他类型的线粒体中看到的那样 研究(见CS子项目“线粒体的电子断层摄影术： 膜相互作用“)。基质材料被狭隘地限制 在立方相中的膜之间，从而扭转了通常的 线粒体内的大部分体积是 母体材料。邓博士在布法罗完成了博士学位，然后来了 去奥尔巴尼，作为曼内拉博士实验室的博士后，她在那里继续她的 结构研究。她的下一个优先事项将是对 立方膜。这项工作在两次会议上被正式介绍 还显示了与关于线粒体的一般性讨论有关的信息 曼内拉博士的建筑，在几个地点。手稿已经准备好了 以供提交。首页--期刊主要分类--期刊细介绍--期刊题录与文摘--期刊细介绍 Rath，B.K.，Mannella，C.A.(1998)周期的三维结构 杂乱阿米巴线粒体内的立方相内膜 卡罗琳。《显微镜与显微分析》第4卷，增刊。2(过程 显微镜和显微分析‘98)Ed.G.Bailey等人，Springer， 纽约，pp.432-33。首页--期刊主要分类--期刊细介绍--期刊题录与文摘--文摘内容 Mannella，C.A.(1998)线粒体混乱。奥尔巴尼会议 线粒体研究的前沿。首页--期刊主要分类--期刊细介绍--期刊题录与文摘--期刊细介绍 Mannella，C.A.(1998)阿米巴的立方线粒体膜 用电子层析重建技术研究混沌卡罗琳现象。J. 结构生物。(正在准备中)。

(Supported by NSF DMB 8916315 to C.A. Mannella) Cubic membranes are symmetric, periodic structures that occur in a wide variety of living systems. There are several varieties of crystal structure proposed for the observed membrane arrays in different biological systems. In previous work (Deng, et al. Protozoology, in press), a template matching method was developed to indirectly identify the crystal type, using electron microscopy of amoeba mitochondria. In this work, we determined the crystal type from IVEM tomographic reconstructions, in comparison to a computer-generated model volume of a perfect crystal of the appropriate type. This validated the template-matching method. We made reconstructions of mitochondria representing examples of two different crystal types, the double-diamond and the gyroid. Extensive use of computer visualization and modeling methods enabled us to not only determine the crystal type but also to understand how the cubic membranes are integrated into the architecture of the mitochondrion, giving insights into their function. In the two examples, the spaces in the cubic area were shown to be intracristal space, which was connected to the space between the inner and outer mitochondrial membranes by tubular connecting regions, as seen in the other types of mitochondria we have studied (see CS subproject "Electron tomography of mitochondria: membrane interactions"). The matrix material was narrowly confined between the membranes in the cubic phase, thus reversing the usual situation in which most of the volume inside the mitochondria is matrix material. Dr. Deng completed her Ph.D. in Buffalo, then came to Albany as a postdoc in Dr. Mannella's lab, where she continued her structural studies. Her next priority will be functional studies on the cubic membranes. The work was formally presented at two meetings and also shown in connection with general talks on mitochondrial structure by Dr. Mannella, at several venues. A manuscript is ready for submission. Deng, Y., Mieczkowski, M., Marko, M., Buttle, K., Rath, B.K., Mannella, C.A. (1998) 3-D structure of periodic cubic-phase inner membranes in mitochondria of the amoebae Chaos carolinensis. Microscopy and Microanalysis vol 4, suppl. 2 (Proc. Microscopy and Microanalysis '98) Ed. G. Bailey, et al., Springer , New York, pp. 432-33. Deng, Y., Marko, M., Buttle, K., Leith, A., Mannella, C.A. (1998) Mitochondria in Chaos. Albany Conference on Frontiers of Mitochondrial Research. Deng, Y., Marko, M., Buttle, K., Mannella, C.A. (1998) Cubic mitochondrial membranes of the amoebae Chaos carolinsis studied by electron tomographic reconstruction. J. Structural Biol. (in preparation).