5月26日，纤毛组进行题为“Asymmetric distribution and spatial switching of dynein activity generates ciliary motility”的journal club。
Motile cilia and flagella are highly conserved, hairlike appendages of eukaryotic cells that propel the movement of cells or fluids. They play important roles in the normal development and health of many species, including humans. Flagellar beating is driven by the coordinated activities of multiple dynein isoforms that must be spatially and temporally regulated. Although the prevailing “switch-point” hypothesis posits that flagellar motility results from periodic switching of spatially restricted, asymmetrical activation of dyneins, no direct evidence has been reported, and how the thousands of dyneins inside a flagellum work together to generate flagellar motility remains elusive.
Our comprehensive structural analysis combined with biochemical investigations provides an enhanced understanding of the distinct roles played by various dyneins and regulatory complexes in the motility of cilia and flagella and suggests critical modifications to previous hypotheses regarding robust molecular mechanisms underlying flagellar motility. Our study demonstrates that comparative cellular cryo-ET studies provide the conceptual framework and experimentaltoolstobetterunderstand molecular mechanisms and cellular functions.
Asymmetric dynein activity underlies beating of cilia and flagella.