Internal Medicine, University of New Mexico Health Science Center, Albuquerque, NM, USA.
Results Probl Cell Differ. 2024;73:155-171. doi: 10.1007/978-3-031-62036-2_8.
Tunneling nanotubes (TNTs) are open-ended, membrane-encased extensions that connect neighboring cells. They have diameters up to 1 μm but are able to expand to convey large cargos. Lengths vary depending on the distance of the cells but have been reported to be capable of extending beyond 300 μm. They have actin cytoskeletons that are essential for their formation, and may or may not have microtubule networks. It is thought that thin TNTs lack microtubules, while thicker TNTs have microtubular highways that use motor proteins to convey materials, including proteins, mitochondria, and nanoparticles between cells. Specifically, the presence of dynein and myosin support trafficking of cargo in both directions. The purpose of these connections is to enable cells to work as a unit or to extend cell life by diluting cytotoxic agents or acquiring biological material needed to survive.
隧道纳米管（TNTs）是一种开口的、膜包裹的延伸结构，连接着相邻的细胞。它们的直径可达 1 微米，但能够扩展以传递大的货物。长度取决于细胞的距离，但据报道，它们能够延伸超过 300 微米。它们具有肌动蛋白细胞骨架，这对它们的形成是必不可少的，并且可能有或可能没有微管网络。人们认为，细的 TNTs 缺乏微管，而较厚的 TNTs 则具有微管高速公路，利用马达蛋白在细胞之间传递物质，包括蛋白质、线粒体和纳米颗粒。具体来说，动力蛋白和肌球蛋白的存在支持货物在两个方向上的运输。这些连接的目的是使细胞能够作为一个单元工作，或者通过稀释细胞毒性剂或获取生存所需的生物材料来延长细胞寿命。
