Cell cycle-specific loading of condensin I is regulated by the N-terminal tail of its kleisin subunit
- RIKEN, Japan
- Nagoya University, Japan
Abstract
Condensin I is a pentameric protein complex that plays an essential role in mitotic chromosome assembly in eukaryotic cells. Although it has been shown that condensin I loading is mitosis-specific, it remains poorly understood how the robust cell cycle regulation of condensin I is achieved. Here we set up a panel of in vitro assays to demonstrate that cell cycle-specific loading of condensin I is regulated by the N-terminal tail (N-tail) of its kleisin subunit CAP-H. Deletion of the N-tail accelerates condensin I loading and chromosome assembly in Xenopus egg mitotic extracts. Phosphorylation-deficient and phosphorylation-mimetic mutations in the CAP-H N-tail decelerate and accelerate condensin I loading, respectively. Remarkably, deletion of the N-tail enables condensin I to assemble mitotic chromosome-like structures even in interphase extracts. Together with other extract-free functional assays in vitro, our results uncover one of the multilayered mechanisms that ensure cell cycle-specific loading of condensin I onto chromosomes.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file;
Article and author information
Author details
Kazuhisa Kinoshita
Funding
Japan Society for the Promotion of Science (#17K15070)
- Shoji Tane
Japan Society for the Promotion of Science (#19H05755)
- Keishi Shintomi
Japan Society for the Promotion of Science (#22H02551)
- Keishi Shintomi
Japan Society for the Promotion of Science (#19K06499)
- Kazuhisa Kinoshita
Japan Society for the Promotion of Science (#20H05937)
- Tomoko Nishiyama
Japan Society for the Promotion of Science (#18H05276)
- Tatsuya Hirano
Japan Society for the Promotion of Science (#20H0593)
- Tatsuya Hirano
Precursory Research for Embryonic Science and Technology (JPMJPRK4)
- Tomoko Nishiyama
Japan Society for the Promotion of Science (#20K15723)
- Tomoko Nishiyama
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Female Xenopus laevis frogs (RRID: NXR 0.031, Hamamatsu Seibutsu-Kyozai) were used to lay eggs to harvest Xenopus egg extract (Hirano et al., 1997). Frogs were used in compliance with the institutional regulations of the RIKEN Wako Campus. Mice (BALB/c × C57BL/6J)F1) for sperm nuclei (Shintomi et al., 2017) were used in compliance with protocols approved by the Animal Care and Use Committee of the University of Tokyo (for M. Ohsugi who provided mouse sperm).
Copyright
© 2022, Tane 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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Cell cycle-specific loading of condensin I is regulated by the N-terminal tail of its kleisin subunit
eLife 11:e84694.
https://doi.org/10.7554/eLife.84694
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