Molecular model of the mitochondrial genome segregation machinery in Trypanosoma brucei.
Molecular model of the mitochondrial genome segregation machinery in Trypanosoma brucei.
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DOI：
10.1073/pnas.1716582115
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发表时间：
2018-02-20
影响因子：
11.1
通讯作者：
Ochsenreiter T
中科院分区：
文献类型：
--
作者：
Hoffmann A;Käser S;Jakob M;Amodeo S;Peitsch C;Týč J;Vaughan S;Zuber B;Schneider A;Ochsenreiter T
线粒体基因组的复制和分离是大多数真核细胞中必不可少的过程。虽然复制已经被研究得相当详细，但对复制基因组所需的分子机制知之甚少。使用超分辨率显微镜与分子生物学和生物化学相结合，我们表明，在该顺序的隔离机械组装，它可能是从头组装，而不是在单细胞寄生虫布氏锥虫在一个保守的方式。此外，我们证明了线粒体基因组本身并不是组装所必需的。似乎线粒体基因组与细胞骨架元件的物理连接在大多数真核生物中是保守的特征;然而，分子组分是高度多样的。在几乎所有的真核生物中，线粒体都有自己的基因组。尽管50多年前就有了这一发现，但人们对基因组在细胞分裂过程中如何正确分离仍然知之甚少。原生动物寄生虫布氏锥虫含有一个具有单一基因组的单克隆体，即动基体DNA（kDNA）。电子显微镜研究显示，在细胞周期期间，三重附着复合物（TAC）将kDNA物理连接到鞭毛的基体，并通过基体运动确保线粒体基因组的正确分离。使用超分辨率显微镜，我们精确地定位每个目前已知的TAC组件。我们证明，TAC组装在一个层次的顺序从鞭毛的基础上对线粒体基因组，并组装是不依赖于kDNA本身。基于生物化学分析，TAC由几个不重叠的亚复合物组成，表明TAC的总大小超过2.8 mDa。我们还表明，TAC是正确的线粒体细胞器定位所需的，但不是细胞器的生物发生或分离。
Mitochondrial genome replication and segregation are essential processes in most eukaryotic cells. While replication has been studied in some detail, much less is known about the molecular machinery required to distribute the replicated genomes. Using superresolution microscopy in combination with molecular biology and biochemistry, we show in which order the segregation machinery is assembled and that it is likely assembled de novo rather than in a semiconservative fashion in the single-celled parasite Trypanosoma brucei. Furthermore, we demonstrate that the mitochondrial genome itself is not required for assembly to occur. It seems that the physical connection of the mitochondrial genome to cytoskeletal elements is a conserved feature in most eukaryotes; however, the molecular components are highly diverse. In almost all eukaryotes, mitochondria maintain their own genome. Despite the discovery more than 50 y ago, still very little is known about how the genome is correctly segregated during cell division. The protozoan parasite Trypanosoma brucei contains a single mitochondrion with a singular genome, the kinetoplast DNA (kDNA). Electron microscopy studies revealed the tripartite attachment complex (TAC) to physically connect the kDNA to the basal body of the flagellum and to ensure correct segregation of the mitochondrial genome via the basal bodies movement, during the cell cycle. Using superresolution microscopy, we precisely localize each of the currently known TAC components. We demonstrate that the TAC is assembled in a hierarchical order from the base of the flagellum toward the mitochondrial genome and that the assembly is not dependent on the kDNA itself. Based on the biochemical analysis, the TAC consists of several nonoverlapping subcomplexes, suggesting an overall size of the TAC exceeding 2.8 mDa. We furthermore demonstrate that the TAC is required for correct mitochondrial organelle positioning but not for organelle biogenesis or segregation.
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DOI：
10.1073/pnas.140063197
发表时间：
2000-07-05
影响因子：
11.1
作者：
Kaufman, BA;Newman, SM;Butow, RA
通讯作者：
Butow, RA
DOI：
10.1073/pnas.1305404110
发表时间：
2013-09-03
影响因子：
11.1
作者：
Dean, Samuel;Gould, Matthew K.;Schnaufer, Achim C.
通讯作者：
Schnaufer, Achim C.
影响因子：
1.5
作者：
Burkard, Gabriela;Fragoso, Cristina M.;Roditi, Isabel
通讯作者：
Roditi, Isabel
布鲁氏血流形式的细胞周期中的线粒体生长。
影响因子：
4.6
作者：
Jakob M;Hoffmann A;Amodeo S;Peitsch C;Zuber B;Ochsenreiter T
通讯作者：
Ochsenreiter T
影响因子：
--
作者：
Clayton, April M.;Guler, Jennifer L.;Englund, Paul T.
通讯作者：
Englund, Paul T.