Oscillatory movement of a dynein-microtubule complex crosslinked with DNA origami

Hirose, K.; Higuchi, H.; Abdellatef, S. A.; Tadakuma, H.; Yan, K.; Fujiwara, T.; Fukumoto, K.; Kondo, Y.; Takazaki, H.; Boudria, R.; Yasunaga, T.

doi:10.1101/2021.12.06.471346

bioRxiv · 10.1101/2021.12.06.471346

Oscillatory movement of a dynein-microtubule complex crosslinked with DNA origami

Hirose, K.·Higuchi, H.·Abdellatef, S. A.·Tadakuma, H.·Yan, K.·Fujiwara, T.·Fukumoto, K.·Kondo, Y.·Takazaki, H.·Boudria, R.·Yasunaga, T.

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Abstract

During repetitive bending of cilia and flagella, axonemal dynein molecules move in an oscillatory manner along a microtubule (MT), but how the minus-end-directed motor dynein can oscillate back and forth is unknown. There are various factors that may regulate the dynein activities, e.g., the nexin-dynein regulatory complex, radial spokes, and central apparatus. In order to understand the basic mechanism of the oscillatory movement, we constructed a simple model system composed of MTs, outer-arm dyneins, and DNA origami that crosslinks the MTs. Electron microscopy (EM) showed patches of dynein molecules crossbridging two MTs in two opposite orientations; the oppositely oriented dyneins are expected to produce opposing forces. The optical trapping experiments showed that the dynein-MT-DNA-origami complex actually oscillate back and forth after photolysis of caged ATP. Intriguingly, the complex, when held at one end, showed repetitive bending motions. The results show that a simple system composed of ensembles of oppositely oriented dyneins, MTs, and inter-MT crosslinkers, without the additional regulatory structures, has an intrinsic ability to cause oscillation and repetitive bending motions.

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Hirose, K., Higuchi, H., Abdellatef, S. A., Tadakuma, H., Yan, K., Fujiwara, T., Fukumoto, K., Kondo, Y., Takazaki, H., Boudria, R., Yasunaga, T.. 2021-12-07. Oscillatory movement of a dynein-microtubule complex crosslinked with DNA origami. https://doi.org/10.1101/2021.12.06.471346

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