Microtubule stabilizer reveals requirement of Ca2+-dependent conformational changes of microtubules for rapid coiling of haptonema in haptophyte algae
Abstract
<jats:p>A haptonema is an elongated microtubule-based motile organelle uniquely present in haptophytes. The most notable and rapid movement of a haptonema is “coiling”, which occurs within a few milliseconds following mechanical stimulation in an unknown motor-independent mechanism. Here, we analyzed the coiling process in detail by high-speed filming and showed that haptonema coiling was initiated by left-handed twisting of the haptonema, followed by writhing to form a helix from the distal tip. On recovery from a mechanical stimulus, the helix slowly uncoiled from the proximal region. Electron microscopy showed that the seven microtubules in a haptonema were arranged mostly in parallel but that one of the microtubules often wound around the others in the extended state. A microtubule stabilizer, paclitaxel, inhibited coiling and induced right-handed twisting of the haptonema in the absence of Ca2+, suggesting changes in the microtubule surface lattice. Addition of Ca2+ caused bend propagation toward the proximal region. These results indicate that switching microtubule conformation, possibly with the aid of Ca2+-binding microtubule-associated proteins is responsible for rapid haptonematal coiling.</jats:p>
Journal
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- Biology open
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Biology open 8 (2), bio036590-, 2019-02
Company of Biologists
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Keywords
Details 詳細情報について
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- CRID
- 1050001202561842432
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- NII Article ID
- 120007128081
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- ISSN
- 20466390
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- HANDLE
- 2241/00155465
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- Web Site
- https://tsukuba.repo.nii.ac.jp/records/50012
- https://syndication.highwire.org/content/doi/10.1242/bio.036590
- http://journals.logists.com/bio/bio/article-pdf/doi/10.1242/bio.036590/1828936/bio036590.pdf
- http://journals.logists.com/bio/bio/article-pdf/doi/10.1242/bio.036590/2051200/bio_036590v1.pdf
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- Text Lang
- en
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- Article Type
- journal article
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- Data Source
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- IRDB
- Crossref
- CiNii Articles
- KAKEN