Three-dimensional periodic cubic membrane structure in the mitochondria of amoebae Chaos carolinensis
Three-dimensional periodic cubic membrane structure in the mitochondria of amoebae Chaos carolinensis
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DOI：
10.1007/bf01280583
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发表时间：
1998-01-01
期刊：
影响因子：
2.9
通讯作者：
Mieczkowski, M
中科院分区：
文献类型：
--
作者：
Deng, YR;Mieczkowski, M
通过计算机模拟透射电子显微镜（TEM）产生的图像，我们确定了巨型阿米巴（Chaos carolinensis）线粒体的三维周期性立方膜结构。立方膜是基于高度弯曲的三维周期立方表面，共享相同的几何形状的数学定义的周期最小曲面。这里确定的双膜结构将空间划分为三个独立和卷曲的子空间。样品制备，特别是这种膜晶体斜切的倾向，增加了TEM投影的复杂性，直到现在，研究人员还无法识别它们。然而，斜剖面的复杂性增加了，这使得我们能够将透射电镜投影与计算机模拟相匹配。在这项研究中，发现变形虫线粒体中立方膜结构的形成依赖于饮食。立方体结构只在没有食物的情况下出现，在有食物的情况下消失，这表明变形虫在自然界中生存的结构适应和可能的优势。在未喂食的变形虫线粒体中，数学上定义明确的结构的验证对于理解线粒体生物能量学与内膜拓扑结构的关系也很重要，内膜是主要的细胞能量产生和自由基产生的地方。就衰老和与年龄相关的退行性疾病而言，这一认识可能对人类健康产生重大影响，特别是因为线粒体疾病与这些过程有关。
Through computer simulation of images produced by the transmission electron microscope (TEM), we have identified three-dimensional periodic cubic membrane structures in giant amoebae (Chaos carolinensis) mitochondria. The cubic membranes are based on the highly curved three-dimensional periodic cubic surfaces, sharing the same geometry of mathematically defined periodic minimal surfaces. The double-membrane structures identified here divide space into three separate and convoluted subspaces. Specimen preparation, specifically the tendency to cut oblique sections, of this membrane crystal has added to the complexity of the resulting TEM projections and until now prevented researchers from recognizing them. It is the added complexity of the oblique sections, though, that allows us to match the TEM projection to a computer simulation of the same with confidence. In this study, formation of cubic membrane structures in amoeba mitochondria was found to be dependent on diet. The cubic structures only occurred in the absence of food, and disappeared in the presence of food, suggesting a structural adaptation and possible advantages for amoeba's survival in nature. The verification of mathematically well-defined structures in unfed amoeba mitochondria is also important to the understanding of the mitochondrial bioenergetics in relation to the topology of the inner membrane, where major cellular energy production as well as free-radical generation are taking place. This understanding may carry great impact upon human health as far as aging and age-related degenerative diseases are concerned, especially as mitochondrial disorders have been implicated in these processes.