Dayal Alexander A, Parfenteva Olga I, Huiying Wang, Shakhov Anton S, Alieva Irina B, Minin Alexander A
Institute of Protein Research, Russian Academy of Sciences, Moscow, 119334, Russia.
Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
Biochemistry (Mosc). 2024 Nov;89(11):2028-2036. doi: 10.1134/S0006297924110154.
Intermediate filaments (IFs) represented by a diverse range of proteins, are one of the three main cytoskeleton components in different types of animal cells. IFs provide mechanical strength to cells and help position the nucleus and organelles in the cell. Desmin is an IF protein typical of muscle cells, while vimentin, which has a similar structure, is expressed in many mesenchymal cells. Both proteins are synthesized during myogenesis and regeneration of damaged muscle tissue and form a mixed IF network. Both desmin and vimentin regulate mitochondrial activity, including mitochondrial localization and maintenance of mitochondrial membrane potential, in the corresponding cells, but the role of mixed IFs in the control of mitochondrial functions remains unclear. To investigate how a simultaneous presence of these proteins affects mitochondrial membrane potential, we used BHK21 cells expressing both vimentin and desmin IFs. Expression of vimentin or desmin individually or both proteins simultaneously was suppressed using gene knockout and/or RNA interference. It was found that disruption of biosynthesis of either vimentin or desmin did not affect the mitochondrial membrane potential, which remained unchanged compared to cells expressing both proteins. Simultaneous abolishment of both proteins resulted in a 20% reduction in the mitochondrial membrane potential, indicating that both vimentin and desmin play an equally important role in its maintenance.
中间丝（IFs）由多种蛋白质组成，是不同类型动物细胞中三种主要细胞骨架成分之一。中间丝为细胞提供机械强度，并有助于在细胞内定位细胞核和细胞器。结蛋白是肌肉细胞特有的一种中间丝蛋白，而结构相似的波形蛋白则在许多间充质细胞中表达。这两种蛋白质在肌肉发生和受损肌肉组织的再生过程中合成，并形成混合中间丝网络。结蛋白和波形蛋白都能调节相应细胞中的线粒体活性，包括线粒体定位和线粒体膜电位的维持，但混合中间丝在控制线粒体功能中的作用仍不清楚。为了研究这些蛋白质同时存在如何影响线粒体膜电位，我们使用了同时表达波形蛋白和结蛋白中间丝的BHK21细胞。通过基因敲除和/或RNA干扰抑制波形蛋白或结蛋白单独或两种蛋白同时的表达。结果发现，波形蛋白或结蛋白生物合成的破坏并不影响线粒体膜电位，与同时表达两种蛋白的细胞相比，其保持不变。两种蛋白同时缺失导致线粒体膜电位降低20%，表明波形蛋白和结蛋白在维持线粒体膜电位方面发挥着同等重要的作用。
