Functional exploration of heterotrimeric kinesin-II in IFT and ciliary length control in Chlamydomonas

  1. Shufen Li
  2. Kirsty Y Wan
  3. Wei Chen
  4. Hui Tao
  5. Xin Liang  Is a corresponding author
  6. Junmin Pan  Is a corresponding author
  1. Tsinghua University, China
  2. University of Exeter, United Kingdom

Abstract

Heterodimeric motor organization of kinesin-II is essential for its function in anterograde IFT in ciliogenesis. However, the underlying mechanism is not well understood. In addition, the anterograde IFT velocity varies significantly in different organisms, but how this velocity affects ciliary length is not clear. We show that in Chlamydomonas motors are only stable as heterodimers in vivo, which is likely the key factor for the requirement of a heterodimer for IFT. Second, chimeric CrKinesin-II with human kinesin-II motor domains functioned in vitro and in vivo, leading to a ~2.8-fold reduced anterograde IFT velocity and a similar fold reduction in IFT injection rate that supposedly correlates with ciliary assembly activity. However, the ciliary length was only mildly reduced (~15%). Modelling analysis suggests a nonlinear scaling relationship between IFT velocity and ciliary length that can be accounted for by limitation of the motors and/or its ciliary cargoes, e.g. tubulin.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Part of the source data have been provided for Figure 1-4.

Article and author information

Author details

  1. Shufen Li

    School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    No competing interests declared.
  2. Kirsty Y Wan

    Living Systems Institute, University of Exeter, Exeter, United Kingdom
    Competing interests
    No competing interests declared.
  3. Wei Chen

    School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7454-3882
  4. Hui Tao

    School of Life Sciences, Tsinghua University, Beijing, China
    Competing interests
    No competing interests declared.
  5. Xin Liang

    School of Life Sciences, Tsinghua University, Tsinghua, China
    For correspondence
    xinliang@tsinghua.edu.cn
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7915-8094
  6. Junmin Pan

    School of Life Sciences, Tsinghua University, Beijing, China
    For correspondence
    panjunmin@tsinghua.edu.cn
    Competing interests
    Junmin Pan, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1242-3791

Funding

Ministry of Science and Technology of the People's Republic of China (2017YFA0503500)

  • Junmin Pan

Ministry of Science and Technology of the People's Republic of China (2018YFA0902500)

  • Junmin Pan

National Natural Science Foundation of China (31991191)

  • Junmin Pan

National Natural Science Foundation of China (31671387)

  • Junmin Pan

National Natural Science Foundation of China (31972888)

  • Junmin Pan

National Natural Science Foundation of China (31922018)

  • Xin Liang

Springboard Award from the Academy of Medical Sciences and Global Challenges Research Fund Research Fund (SBF003\1160)

  • Kirsty Y Wan

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ahmet Yildiz, University of California, Berkeley, United States

Version history

  1. Received: May 13, 2020
  2. Accepted: October 28, 2020
  3. Accepted Manuscript published: October 28, 2020 (version 1)
  4. Version of Record published: November 9, 2020 (version 2)

Copyright

© 2020, Li et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Shufen Li
  2. Kirsty Y Wan
  3. Wei Chen
  4. Hui Tao
  5. Xin Liang
  6. Junmin Pan
(2020)
Functional exploration of heterotrimeric kinesin-II in IFT and ciliary length control in Chlamydomonas
eLife 9:e58868.
https://doi.org/10.7554/eLife.58868

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https://doi.org/10.7554/eLife.58868

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