Insight into the regulation of complex physiological systems emerges from understanding how biological units communicate with each other. Recent findings show that mitochondria communicate at a distance with each other via nanotunnels, thin double-membrane protrusions that connect the matrices of non-adjacent mitochondria. Emerging evidence suggest that mitochondrial nanotunnels are generated by immobilized mitochondria and transport proteins. This review integrates data from the evolutionarily conserved structure and function of intercellular projections in bacteria with recent developments in mitochondrial imaging that permit nanotunnel visualization in eukaryotes. Cell type-specificity, timescales, and the selective size-based diffusion of biomolecules along nanotunnels are also discussed. The joining of individual mitochondria into dynamic networks of communicating organelles via nanotunnels and other mechanisms has major implications for organelle and cellular behaviors.

对复杂生理系统调节的洞察源于对生物单元如何相互交流的理解。最近的研究结果表明，线粒体通过纳米隧道（连接非相邻线粒体基质的薄双膜突起）在一定距离内相互通信。新出现的证据表明，线粒体纳米隧道是由固定的线粒体和转运蛋白产生的。这篇综述将细菌细胞间投射的进化保守结构和功能的数据与线粒体成像的最新发展相结合，这些发展允许真核生物中的纳米隧道可视化。还讨论了细胞类型特异性、时间尺度和生物分子沿纳米隧道的基于尺寸的选择性扩散。