TY - JOUR
T1 - Asymmetric distribution and spatial switching of dynein activity generates ciliary motility
AU - Lin, Jianfeng
AU - Nicastro, Daniela
N1 - Publisher Copyright:
© The Authors.
PY - 2018/4/27
Y1 - 2018/4/27
N2 - Motile cilia and flagella are essential, highly conserved organelles, and their motility is driven by the coordinated activities of multiple dynein isoforms. The prevailing “switch-point” hypothesis posits that dyneins are asymmetrically activated to drive flagellar bending. To test this model, we applied cryo–electron tomography to visualize activity states of individual dyneins relative to their locations along beating flagella of sea urchin sperm cells. As predicted, bending was generated by the asymmetric distribution of dynein activity on opposite sides of the flagellum. However, contrary to predictions, most dyneins were in their active state, and the smaller population of conformationally inactive dyneins switched flagellar sides relative to the bending direction. Thus, our data suggest a “switch-inhibition” mechanism in which force imbalance is generated by inhibiting, rather than activating, dyneins on alternating sides of the flagellum.
AB - Motile cilia and flagella are essential, highly conserved organelles, and their motility is driven by the coordinated activities of multiple dynein isoforms. The prevailing “switch-point” hypothesis posits that dyneins are asymmetrically activated to drive flagellar bending. To test this model, we applied cryo–electron tomography to visualize activity states of individual dyneins relative to their locations along beating flagella of sea urchin sperm cells. As predicted, bending was generated by the asymmetric distribution of dynein activity on opposite sides of the flagellum. However, contrary to predictions, most dyneins were in their active state, and the smaller population of conformationally inactive dyneins switched flagellar sides relative to the bending direction. Thus, our data suggest a “switch-inhibition” mechanism in which force imbalance is generated by inhibiting, rather than activating, dyneins on alternating sides of the flagellum.
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U2 - 10.1126/science.aar1968
DO - 10.1126/science.aar1968
M3 - Article
C2 - 29700238
AN - SCOPUS:85046041426
SN - 0036-8075
VL - 360
JO - Science
JF - Science
IS - 6387
M1 - eaar1968
ER -