Cargando…

Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility

Tubulins undergo various posttranslational modifications. Among them, polyglutamylation is involved in the motility of eukaryotic flagella and the stability of the axonemal microtubules. However, it remains unclear where polyglutamylated tubulin localizes precisely within the axoneme and how tubulin...

Descripción completa

Detalles Bibliográficos
Autores principales: Kubo, Tomohiro, Oda, Toshiyuki
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The American Society for Cell Biology 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5555654/
https://www.ncbi.nlm.nih.gov/pubmed/28637765
http://dx.doi.org/10.1091/mbc.E17-05-0285
_version_ 1783256951601233920
author Kubo, Tomohiro
Oda, Toshiyuki
author_facet Kubo, Tomohiro
Oda, Toshiyuki
author_sort Kubo, Tomohiro
collection PubMed
description Tubulins undergo various posttranslational modifications. Among them, polyglutamylation is involved in the motility of eukaryotic flagella and the stability of the axonemal microtubules. However, it remains unclear where polyglutamylated tubulin localizes precisely within the axoneme and how tubulin polyglutamylation affects flagellar motility. In this study, we identified the three-dimensional localization of the polyglutamylated tubulin in Chlamydomonas flagella using antibody labeling and cryo–electron tomography. Polyglutamylated tubulins specifically located in close proximity to a microtubule-cross-bridging structure called the nexin–dynein regulatory complex (N-DRC). Because N-DRC is positively charged, we hypothesized that there is an electrostatic interaction between the polyglutamylated tubulin and the N-DRC, and therefore we mutated the amino acid sequences of DRC4 to modify the charge of the N-DRC. We found that both augmentation and reduction of the positive charge on DRC4 resulted in reduced flagellar motility. Moreover, reduced motility in a mutant with a structurally defective N-DRC was partially restored by increasing the positive charge on DRC4. These results clearly indicate that beating motion of flagella is maintained by the electrostatic cross-bridge formed between the negatively charged polyglutamylated tubulins and the positively charged N-DRC.
format Online
Article
Text
id pubmed-5555654
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher The American Society for Cell Biology
record_format MEDLINE/PubMed
spelling pubmed-55556542017-10-30 Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility Kubo, Tomohiro Oda, Toshiyuki Mol Biol Cell Brief Reports Tubulins undergo various posttranslational modifications. Among them, polyglutamylation is involved in the motility of eukaryotic flagella and the stability of the axonemal microtubules. However, it remains unclear where polyglutamylated tubulin localizes precisely within the axoneme and how tubulin polyglutamylation affects flagellar motility. In this study, we identified the three-dimensional localization of the polyglutamylated tubulin in Chlamydomonas flagella using antibody labeling and cryo–electron tomography. Polyglutamylated tubulins specifically located in close proximity to a microtubule-cross-bridging structure called the nexin–dynein regulatory complex (N-DRC). Because N-DRC is positively charged, we hypothesized that there is an electrostatic interaction between the polyglutamylated tubulin and the N-DRC, and therefore we mutated the amino acid sequences of DRC4 to modify the charge of the N-DRC. We found that both augmentation and reduction of the positive charge on DRC4 resulted in reduced flagellar motility. Moreover, reduced motility in a mutant with a structurally defective N-DRC was partially restored by increasing the positive charge on DRC4. These results clearly indicate that beating motion of flagella is maintained by the electrostatic cross-bridge formed between the negatively charged polyglutamylated tubulins and the positively charged N-DRC. The American Society for Cell Biology 2017-08-15 /pmc/articles/PMC5555654/ /pubmed/28637765 http://dx.doi.org/10.1091/mbc.E17-05-0285 Text en © 2017 Kubo and Oda. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,” “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society for Cell Biology.
spellingShingle Brief Reports
Kubo, Tomohiro
Oda, Toshiyuki
Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title_full Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title_fullStr Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title_full_unstemmed Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title_short Electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
title_sort electrostatic interaction between polyglutamylated tubulin and the nexin–dynein regulatory complex regulates flagellar motility
topic Brief Reports
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5555654/
https://www.ncbi.nlm.nih.gov/pubmed/28637765
http://dx.doi.org/10.1091/mbc.E17-05-0285
work_keys_str_mv AT kubotomohiro electrostaticinteractionbetweenpolyglutamylatedtubulinandthenexindyneinregulatorycomplexregulatesflagellarmotility
AT odatoshiyuki electrostaticinteractionbetweenpolyglutamylatedtubulinandthenexindyneinregulatorycomplexregulatesflagellarmotility