Ranftler Carmen, Meisslitzer-Ruppitsch Claudia, Neumüller Josef, Ellinger Adolf, Pavelka Margit
Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstraße 17, 1090, Vienna, Austria.
Histochem Cell Biol. 2017 Apr;147(4):415-438. doi: 10.1007/s00418-016-1515-7. Epub 2016 Dec 14.
We studied Golgi apparatus disorganizations and reorganizations in human HepG2 hepatoblastoma cells by using the nonmetabolizable glucose analogue 2-deoxy-D-glucose (2DG) and analyzing the changes in Golgi stack architectures by 3D-electron tomography. Golgi stacks remodel in response to 2DG-treatment and are replaced by tubulo-glomerular Golgi bodies, from which mini-Golgi stacks emerge again after removal of 2DG. The Golgi stack changes correlate with the measured ATP-values. Our findings indicate that the classic Golgi stack architecture is impeded, while cells are under the influence of 2DG at constantly low ATP-levels, but the Golgi apparatus is maintained in forms of the Golgi bodies and Golgi stacks can be rebuilt as soon as 2DG is removed. The 3D-electron microscopic results highlight connecting regions that interlink membrane compartments in all phases of Golgi stack reorganizations and show that the compact Golgi bodies mainly consist of continuous intertwined tubules. Connections and continuities point to possible new transport pathways that could substitute for other modes of traffic. The changing architectures visualized in this work reflect Golgi stack dynamics that may be essential for basic cell physiologic and pathologic processes and help to learn, how cells respond to conditions of stress.
我们通过使用不可代谢的葡萄糖类似物2-脱氧-D-葡萄糖(2DG)并通过三维电子断层扫描分析高尔基体堆叠结构的变化,研究了人肝癌细胞系HepG2中高尔基体的紊乱和重组。高尔基体堆叠会响应2DG处理而重塑,并被肾小管状高尔基体取代,在去除2DG后,又会从小管状高尔基体中再次出现微型高尔基体堆叠。高尔基体堆叠的变化与测得的ATP值相关。我们的研究结果表明,在细胞处于持续低ATP水平且受2DG影响时,经典的高尔基体堆叠结构受到阻碍,但高尔基体以高尔基体的形式得以维持,并且一旦去除2DG,高尔基体堆叠就能重建。三维电子显微镜结果突出显示了在高尔基体堆叠重组的所有阶段中连接膜隔室的连接区域,并表明紧密的高尔基体主要由连续交织的小管组成。连接和连续性指向可能替代其他运输方式的新运输途径。这项工作中可视化的不断变化的结构反映了高尔基体堆叠动力学,这可能对基本细胞生理和病理过程至关重要,并有助于了解细胞如何应对应激条件。