Systematic studies of all PIH proteins in zebrafish reveal their distinct roles in axonemal dynein assembly
Construction of motile cilia/flagella requires cytoplasmic preassembly of axonemal dyneins before transport into cilia. Axonemal dyneins have various subtypes, but the roles of each dynein subtype and their assembly processes remain elusive in vertebrates. The PIH protein family, consisting of four members, has been implicated in the assembly of different dynein subtypes, although evidence for this idea is sparse. Here, we established zebrafish mutants of all four PIH-protein genes: pih1d1, pih1d2, ktu, and twister, and analyzed the structures of axonemal dyneins in mutant spermatozoa by cryo-electron tomography. Mutations caused the loss of specific dynein subtypes, which was correlated with abnormal sperm motility. We also found organ-specific compositions of dynein subtypes, which could explain the severe motility defects of mutant Kupffer's vesicle cilia. Our data demonstrate that all vertebrate PIH proteins are differently required for cilia/flagella motions and the assembly of axonemal dyneins, assigning specific dynein subtypes to each PIH protein.
All data generated or analysed during this study are included in the manuscript and supporting files. All the electron density maps derived from cryo-electron tomography are deposited in EMD under the following accession numbers: WT, EMD-6954; pih1d1-/-, EMD-6955; pih1d2-/-, EMD-6956; ktu-/-, EMD-6957; twister-/-, EMD-6958; pih1d2-/-;ktu-/- (+OAD class), EMD-6959; and pih1d2-/-;ktu-/- (-OAD class), EMD-6960.
Article and author information
Core Research for Evolutional Science and Technology (JPMJCR14M1)
- Masahide Kikkawa
Japan Society for the Promotion of Science (16H02502)
- Masahide Kikkawa
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Andrew P Carter, MRC Laboratory of Molecular Biology, United Kingdom
- Received: March 26, 2018
- Accepted: May 5, 2018
- Accepted Manuscript published: May 9, 2018 (version 1)
- Version of Record published: June 19, 2018 (version 2)
© 2018, Yamaguchi 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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