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Liu S, Zhang J, Kherraf ZE, Sun S, Zhang X, Cazin C, Coutton C, Zouari R, Zhao S, Hu F, Fourati Ben Mustapha S, Arnoult C, Ray PF, Liu M. CFAP61 is required for sperm flagellum formation and male fertility in human and mouse. Development 2021; 148:273455. [PMID: 34792097 DOI: 10.1242/dev.199805] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022]
Abstract
Defects in the structure or motility of cilia and flagella may lead to severe diseases such as primary ciliary dyskinesia (PCD), a multisystemic disorder with heterogeneous manifestations affecting primarily respiratory and reproductive functions. We report that CFAP61 is a conserved component of the calmodulin- and radial spoke-associated complex (CSC) of cilia. We find that a CFAP61 splice variant, c.143+5G>A, causes exon skipping/intron retention in human, inducing a multiple morphological abnormalities of the flagella (MMAF) phenotype. We generated Cfap61 knockout mice that recapitulate the infertility phenotype of the human CFAP61 mutation, but without other symptoms usually observed in PCD. We find that CFAP61 interacts with the CSC, radial spoke stalk and head. During early stages of Cfap61-/- spermatid development, the assembly of radial spoke components is impaired. As spermiogenesis progresses, the axoneme in Cfap61-/- cells becomes unstable and scatters, and the distribution of intraflagellar transport proteins is disrupted. This study reveals an organ-specific mechanism of axoneme stabilization that is related to male infertility.
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Affiliation(s)
- Siyu Liu
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, 211166, China
| | - Jintao Zhang
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, 211166, China
| | - Zine Eddine Kherraf
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, F-38000, France.,CHU de Grenoble, UM GI-DPI, Grenoble, F-38000, France
| | - Shuya Sun
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, 211166, China
| | - Xin Zhang
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, 211166, China
| | - Caroline Cazin
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, F-38000, France.,CHU de Grenoble, UM GI-DPI, Grenoble, F-38000, France
| | - Charles Coutton
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, F-38000, France.,CHU de Grenoble, UM de Génétique Chromosomique, Grenoble, F-38000, France
| | - Raoudha Zouari
- Polyclinique les Jasmins, Centre d'Aide Médicale à la Procréation, Centre Urbain Nord, 1003 Tunis, Tunisia
| | - Shuqin Zhao
- State Key Laboratory of Reproductive Medicine, Animal Core Facility of Nanjing Medical University, Nanjing 211166, China
| | - Fan Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | | | - Christophe Arnoult
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, F-38000, France
| | - Pierre F Ray
- Univ. Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Grenoble, F-38000, France.,CHU de Grenoble, UM GI-DPI, Grenoble, F-38000, France
| | - Mingxi Liu
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, 211166, China
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2
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Composition and function of the C1b/C1f region in the ciliary central apparatus. Sci Rep 2021; 11:11760. [PMID: 34083607 PMCID: PMC8175508 DOI: 10.1038/s41598-021-90996-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/19/2021] [Indexed: 02/04/2023] Open
Abstract
Motile cilia are ultrastructurally complex cell organelles with the ability to actively move. The highly conserved central apparatus of motile 9 × 2 + 2 cilia is composed of two microtubules and several large microtubule-bound projections, including the C1b/C1f supercomplex. The composition and function of C1b/C1f subunits has only recently started to emerge. We show that in the model ciliate Tetrahymena thermophila, C1b/C1f contains several evolutionarily conserved proteins: Spef2A, Cfap69, Cfap246/LRGUK, Adgb/androglobin, and a ciliate-specific protein Tt170/TTHERM_00205170. Deletion of genes encoding either Spef2A or Cfap69 led to a loss of the entire C1b projection and resulted in an abnormal vortex motion of cilia. Loss of either Cfap246 or Adgb caused only minor alterations in ciliary motility. Comparative analyses of wild-type and C1b-deficient mutant ciliomes revealed that the levels of subunits forming the adjacent C2b projection but not C1d projection are greatly reduced, indicating that C1b stabilizes C2b. Moreover, the levels of several IFT and BBS proteins, HSP70, and enzymes that catalyze the final steps of the glycolytic pathway: enolase ENO1 and pyruvate kinase PYK1, are also reduced in the C1b-less mutants.
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3
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Distinct architecture and composition of mouse axonemal radial spoke head revealed by cryo-EM. Proc Natl Acad Sci U S A 2021; 118:2021180118. [PMID: 34871179 DOI: 10.1073/pnas.2021180118] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The radial spoke (RS) heads of motile cilia and flagella contact projections of the central pair (CP) apparatus to coordinate motility, but the morphology is distinct for protozoa and metazoa. Here we show the murine RS head is compositionally distinct from that of Chlamydomonas Our reconstituted murine RS head core complex consists of Rsph1, Rsph3b, Rsph4a, and Rsph9, lacking Rsph6a and Rsph10b, whose orthologs exist in the protozoan RS head. We resolve its cryo-electron microscopy (cryo-EM) structure at 3.2-Å resolution. Our atomic model further reveals a twofold symmetric brake pad-shaped structure, in which Rsph4a and Rsph9 form a compact body extended laterally with two long arms of twisted Rsph1 β-sheets and potentially connected dorsally via Rsph3b to the RS stalk. Furthermore, our modeling suggests that the core complex contacts the periodic CP projections either rigidly through its tooth-shaped Rsph4a regions or elastically through both arms for optimized RS-CP interactions and mechanosignal transduction.
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4
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Miyata H, Abbasi F, Visconti PE, Ikawa M. CRISPR/CAS9-mediated amino acid substitution reveals phosphorylation residues of RSPH6A are not essential for male fertility in mice†. Biol Reprod 2020; 103:912-914. [PMID: 32901808 PMCID: PMC7609874 DOI: 10.1093/biolre/ioaa161] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Haruhiko Miyata
- Department of Experimental Genome Research, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Ferheen Abbasi
- Department of Experimental Genome Research, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Pablo E Visconti
- Department of Veterinary and Animal Sciences, Integrated Sciences Building, University of Massachusetts Amherst, Amherst, MA, USA
| | - Masahito Ikawa
- Department of Experimental Genome Research, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.,The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan
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5
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Oura S, Kazi S, Savolainen A, Nozawa K, Castañeda J, Yu Z, Miyata H, Matzuk RM, Hansen JN, Wachten D, Matzuk MM, Prunskaite-Hyyryläinen R. Cfap97d1 is important for flagellar axoneme maintenance and male mouse fertility. PLoS Genet 2020; 16:e1008954. [PMID: 32785227 PMCID: PMC7444823 DOI: 10.1371/journal.pgen.1008954] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 08/24/2020] [Accepted: 06/24/2020] [Indexed: 11/18/2022] Open
Abstract
The flagellum is essential for sperm motility and fertilization in vivo. The axoneme is the main component of the flagella, extending through its entire length. An axoneme is comprised of two central microtubules surrounded by nine doublets, the nexin-dynein regulatory complex, radial spokes, and dynein arms. Failure to properly assemble components of the axoneme in a sperm flagellum, leads to fertility alterations. To understand this process in detail, we have defined the function of an uncharacterized gene, Cfap97 domain containing 1 (Cfap97d1). This gene is evolutionarily conserved in mammals and multiple other species, including Chlamydomonas. We have used two independently generated Cfap97d1 knockout mouse models to study the gene function in vivo. Cfap97d1 is exclusively expressed in testes starting from post-natal day 20 and continuing throughout adulthood. Deletion of the Cfap97d1 gene in both mouse models leads to sperm motility defects (asthenozoospermia) and male subfertility. In vitro fertilization (IVF) of cumulus-intact oocytes with Cfap97d1 deficient sperm yielded few embryos whereas IVF with zona pellucida-free oocytes resulted in embryo numbers comparable to that of the control. Knockout spermatozoa showed abnormal motility characterized by frequent stalling in the anti-hook position. Uniquely, Cfap97d1 loss caused a phenotype associated with axonemal doublet heterogeneity linked with frequent loss of the fourth doublet in the sperm stored in the epididymis. This study demonstrates that Cfap97d1 is required for sperm flagellum ultra-structure maintenance, thereby playing a critical role in sperm function and male fertility in mice.
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Affiliation(s)
- Seiya Oura
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Samina Kazi
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Audrey Savolainen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Kaori Nozawa
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Center for Drug Discovery, Baylor College of Medicine, Houston, Texas, United States of America
| | - Julio Castañeda
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Zhifeng Yu
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Center for Drug Discovery, Baylor College of Medicine, Houston, Texas, United States of America
| | - Haruhiko Miyata
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Ryan M. Matzuk
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Center for Drug Discovery, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jan N. Hansen
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Bonn, Germany
| | - Dagmar Wachten
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Bonn, Germany
| | - Martin M. Matzuk
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Center for Drug Discovery, Baylor College of Medicine, Houston, Texas, United States of America
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6
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Beneke T, Banecki K, Fochler S, Gluenz E. LAX28 is required for the stable assembly of the inner dynein arm f complex, and the tether and tether head complex in Leishmania flagella. J Cell Sci 2020; 133:jcs239855. [PMID: 31932510 PMCID: PMC7747692 DOI: 10.1242/jcs.239855] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 12/12/2019] [Indexed: 12/26/2022] Open
Abstract
Motile eukaryotic flagella beat through coordinated activity of dynein motor proteins; however, the mechanisms of dynein coordination and regulation are incompletely understood. The inner dynein arm (IDA) f complex (also known as the I1 complex), and the tether and tether head (T/TH) complex are thought to be key regulators of dynein action but, unlike the IDA f complex, T/TH proteins remain poorly characterised. Here, we characterised T/TH-associated proteins in the protist Leishmania mexicana Proteome analysis of axonemes from null mutants for the CFAP44 T/TH protein showed that they lacked the IDA f protein IC140 and a novel 28-kDa axonemal protein, LAX28. Sequence analysis identified similarities between LAX28 and the uncharacterised human sperm tail protein TEX47, both sharing features with sensory BLUF-domain-containing proteins. Leishmania lacking LAX28, CFAP44 or IC140 retained some motility, albeit with reduced swimming speed and directionality and a propensity for flagellar curling. Expression of tagged proteins in different null mutant backgrounds showed that the axonemal localisation of LAX28 requires CFAP44 and IC140, and the axonemal localisations of CFAP44 and IC140 both depend on LAX28. These data demonstrate a role for LAX28 in motility and show mutual dependencies of IDA f and T/TH-associated proteins for axonemal assembly in Leishmania.
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Affiliation(s)
- Tom Beneke
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Katherine Banecki
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Sophia Fochler
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Eva Gluenz
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
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7
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Zhu X, Poghosyan E, Rezabkova L, Mehall B, Sakakibara H, Hirono M, Kamiya R, Ishikawa T, Yang P. The roles of a flagellar HSP40 ensuring rhythmic beating. Mol Biol Cell 2018; 30:228-241. [PMID: 30427757 PMCID: PMC6589562 DOI: 10.1091/mbc.e18-01-0047] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
HSP40s are regarded as cochaperones, perpetually shuttling client polypeptides to HSP70s for refolding. However, many HSP40s that are central for disparate processes diverge from this paradigm. To elucidate the noncanonical mechanisms, we investigated HSP40 in the radial spoke (RS) complex in flagella. Disruption of the gene by the MRC1 transposon in Chlamydomonas resulted in jerky flagella. Traditional electron microscopy, cryo-electron tomography, and sub-tomogram analysis revealed RSs of various altered morphologies that, unexpectedly, differed between the two RS species. This indicates that HSP40 locks the RS into a functionally rigid conformation, facilitating its interactions with the adjacent central pair apparatus for transducing locally varied mechanical feedback, which permits rhythmic beating. Missing HSP40, like missing RSs, could be restored in a tip-to-base direction when HSP40 mutants fused with a HSP40 donor cell. However, without concomitant de novo RS assembly, the repair was exceedingly slow, suggesting HSP40/RS-coupled intraflagellar trafficking and assembly. Biochemical analysis and modeling uncovered spoke HSP40’s cochaperone traits. On the basis of our data, we propose that HSP40 accompanies its client RS precursor when traveling to the flagellar tip. Upon arrival, both refold in concert to assemble into the mature configuration. HSP40’s roles in chaperoning and structural maintenance shed new light on its versatility and flagellar biology.
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Affiliation(s)
- Xiaoyan Zhu
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Emiliya Poghosyan
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Lenka Rezabkova
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Bridget Mehall
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Hitoshi Sakakibara
- National Institute of Information and Communications Technology (NICT), Advanced ICT Research Institute, Hyogo 651-2492, Japan
| | - Masafumi Hirono
- Department of Frontier Bioscience, Hosei University, Tokyo 184-8584, Japan
| | - Ritsu Kamiya
- Department of Life Science, Faculty of Science, Gakushuin University, Tokyo 171-8588, Japan
| | - Takashi Ishikawa
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
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8
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Abbasi F, Miyata H, Shimada K, Morohoshi A, Nozawa K, Matsumura T, Xu Z, Pratiwi P, Ikawa M. RSPH6A is required for sperm flagellum formation and male fertility in mice. J Cell Sci 2018; 131:jcs.221648. [PMID: 30185526 DOI: 10.1242/jcs.221648] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/23/2018] [Indexed: 01/09/2023] Open
Abstract
The flagellum is an evolutionarily conserved appendage used for sensing and locomotion. Its backbone is the axoneme and a component of the axoneme is the radial spoke (RS), a protein complex implicated in flagellar motility regulation. Numerous diseases occur if the axoneme is improperly formed, such as primary ciliary dyskinesia (PCD) and infertility. Radial spoke head 6 homolog A (RSPH6A) is an ortholog of Chlamydomonas RSP6 in the RS head and is evolutionarily conserved. While some RS head proteins have been linked to PCD, little is known about RSPH6A. Here, we show that mouse RSPH6A is testis-enriched and localized in the flagellum. Rsph6a knockout (KO) male mice are infertile as a result of their short immotile spermatozoa. Observation of the KO testis indicates that the axoneme can elongate but is disrupted before accessory structures are formed. Manchette removal is also impaired in the KO testis. Further, RSPH9, another radial spoke protein, disappeared in the Rsph6a KO flagella. These data indicate that RSPH6A is essential for sperm flagellar assembly and male fertility in mice.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Ferheen Abbasi
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Haruhiko Miyata
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
| | - Keisuke Shimada
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
| | - Akane Morohoshi
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kaori Nozawa
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Takafumi Matsumura
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Zoulan Xu
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Putri Pratiwi
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
| | - Masahito Ikawa
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan .,Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan.,Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.,The Institute of Medical Science, University of Tokyo, Tokyo 108-8639, Japan
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9
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Lechtreck KF, Mengoni I, Okivie B, Hilderhoff KB. In vivo analyses of radial spoke transport, assembly, repair and maintenance. Cytoskeleton (Hoboken) 2018; 75:352-362. [PMID: 30070024 DOI: 10.1002/cm.21457] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/04/2018] [Accepted: 06/05/2018] [Indexed: 01/15/2023]
Abstract
Radial spokes (RSs) are multiprotein complexes that regulate dynein activity. In the cell body, RS proteins (RSPs) are present in a 12S precursor, which enters the flagella and converts into the axoneme-bound 20S spokes consisting of a head and stalk. To study RS dynamics in vivo, we expressed fluorescent protein (FP)-tagged versions of the head protein RSP4 and the stalk protein RSP3 to rescue the corresponding Chlamydomonas mutants pf1, lacking spoke heads, and pf14, lacking RSs entirely. RSP3 and RSP4 mostly co-migrated by intraflagellar transport (IFT). The transport was elevated during flagellar assembly and IFT of RSP4-FP depended on RSP3. To study RS assembly independently of ciliogenesis, strains expressing FP-tagged RSPs were mated to untagged cells with, without, or with partial RSs. Tagged RSPs were incorporated in a spotted fashion along wild-type-derived flagella indicating an exchange of RSs. During the repair of pf1-derived axonemes, RSP4-FP is added onto the preexisting spoke stalks with little exchange of RSP3. Thus, RSP3 and RSP4 are transported together but appear to separate inside flagella during the repair of RSs. The 12S RS precursor encompassing both proteins could represent a transport form to ensure stoichiometric delivery of RSPs into flagella by IFT.
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Affiliation(s)
- Karl F Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, Georgia
| | - Ilaria Mengoni
- Department of Cellular Biology, University of Georgia, Athens, Georgia
| | - Batare Okivie
- Department of Cellular Biology, University of Georgia, Athens, Georgia
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10
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Viswanadha R, Sale WS, Porter ME. Ciliary Motility: Regulation of Axonemal Dynein Motors. Cold Spring Harb Perspect Biol 2017; 9:9/8/a018325. [PMID: 28765157 DOI: 10.1101/cshperspect.a018325] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Ciliary motility is crucial for the development and health of many organisms. Motility depends on the coordinated activity of multiple dynein motors arranged in a precise pattern on the outer doublet microtubules. Although significant progress has been made in elucidating the composition and organization of the dyneins, a comprehensive understanding of dynein regulation is lacking. Here, we focus on two conserved signaling complexes located at the base of the radial spokes. These include the I1/f inner dynein arm associated with radial spoke 1 and the calmodulin- and spoke-associated complex and the nexin-dynein regulatory complex associated with radial spoke 2. Current research is focused on understanding how these two axonemal hubs coordinate and regulate the dynein motors and ciliary motility.
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Affiliation(s)
- Rasagnya Viswanadha
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Winfield S Sale
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Mary E Porter
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota 55455
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11
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Zhu X, Liu Y, Yang P. Radial Spokes-A Snapshot of the Motility Regulation, Assembly, and Evolution of Cilia and Flagella. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a028126. [PMID: 27940518 DOI: 10.1101/cshperspect.a028126] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Propulsive forces generated by cilia and flagella are used in events that are critical for the thriving of diverse eukaryotic organisms in their environments. Despite distinctive strokes and regulations, the majority of them adopt the 9+2 axoneme that is believed to exist in the last eukaryotic common ancestor. Only a few outliers have opted for a simpler format that forsakes the signature radial spokes and the central pair apparatus, although both are unnecessary for force generation or rhythmicity. Extensive evidence has shown that they operate as an integral system for motility control. Recent studies have made remarkable progress on the radial spoke. This review will trace how the new structural, compositional, and evolutional insights pose significant implications on flagella biology and, conversely, ciliopathy.
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Affiliation(s)
- Xiaoyan Zhu
- The Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53201
| | - Yi Liu
- The Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53201
| | - Pinfen Yang
- The Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53201
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12
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Pigino G, Ishikawa T. Axonemal radial spokes: 3D structure, function and assembly. BIOARCHITECTURE 2014; 2:50-58. [PMID: 22754630 PMCID: PMC3383722 DOI: 10.4161/bioa.20394] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The radial spoke (RS) is a complex of at least 23 proteins that works as a mechanochemical transducer between the central‐pair apparatus and the peripheral microtubule doublets in eukaryotic flagella and motile cilia. The RS contributes to the regulation of the activity of dynein motors, and thus to flagellar motility. Despite numerous biochemical, physiological and structural studies, the mechanism of the function of the radial spoke remains unclear. Detailed knowledge of the 3D structure of the RS protein complex is needed in order to understand how RS regulates dynein activity. Here we review the most important findings on the structure of the RS, including results of our recent cryo‐electron tomographic analysis of the RS protein complex.
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13
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Oda T, Yanagisawa H, Yagi T, Kikkawa M. Mechanosignaling between central apparatus and radial spokes controls axonemal dynein activity. ACTA ACUST UNITED AC 2014; 204:807-19. [PMID: 24590175 PMCID: PMC3941055 DOI: 10.1083/jcb.201312014] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Nonspecific intermolecular collision between the central pair apparatus and radial spokes underlies a mechanosensing mechanism that regulates dynein activity in Chlamydomonas flagella. Cilia/flagella are conserved organelles that generate fluid flow in eukaryotes. The bending motion of flagella requires concerted activity of dynein motors. Although it has been reported that the central pair apparatus (CP) and radial spokes (RSs) are important for flagellar motility, the molecular mechanism underlying CP- and RS-mediated dynein regulation has not been identified. In this paper, we identified nonspecific intermolecular collision between CP and RS as one of the regulatory mechanisms for flagellar motility. By combining cryoelectron tomography and motility analyses of Chlamydomonasreinhardtii flagella, we show that binding of streptavidin to RS heads paralyzed flagella. Moreover, the motility defect in a CP projection mutant could be rescued by the addition of exogenous protein tags on RS heads. Genetic experiments demonstrated that outer dynein arms are the major downstream effectors of CP- and RS-mediated regulation of flagellar motility. These results suggest that mechanosignaling between CP and RS regulates dynein activity in eukaryotic flagella.
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Affiliation(s)
- Toshiyuki Oda
- Department of Cell Biology and Anatomy, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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14
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Dutcher SK. The awesome power of dikaryons for studying flagella and basal bodies in Chlamydomonas reinhardtii. Cytoskeleton (Hoboken) 2013; 71:79-94. [PMID: 24272949 DOI: 10.1002/cm.21157] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 11/19/2013] [Indexed: 11/08/2022]
Abstract
Cilia/flagella and basal bodies/centrioles play key roles in human health and homeostasis. Among the organisms used to study these microtubule-based organelles, the green alga Chlamydomonas reinhardtii has several advantages. One is the existence of a temporary phase of the life cycle, termed the dikaryon. These cells are formed during mating when the cells fuse and the behavior of flagella from two genetically distinguishable parents can be observed. During this stage, the cytoplasms mix allowing for a defect in the flagella of one parent to be rescued by proteins from the other parent. This offers the unique advantage of adding back wild-type gene product or labeled protein at endogenous levels that can used to monitor various flagellar and basal body phenotypes. Mutants that show rescue and ones that fail to show rescue are both informative about the nature of the flagella and basal body defects. When rescue occurs, it can be used to determine the mutant gene product and to follow the temporal and spatial patterns of flagellar assembly. This review describes many examples of insights into basal body and flagellar proteins' function and assembly that have been discovered using dikaryons and discusses the potential for further analyses.
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Affiliation(s)
- Susan K Dutcher
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri
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15
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Diniz MC, Pacheco ACL, Farias KM, de Oliveira DM. The eukaryotic flagellum makes the day: novel and unforeseen roles uncovered after post-genomics and proteomics data. Curr Protein Pept Sci 2013; 13:524-46. [PMID: 22708495 PMCID: PMC3499766 DOI: 10.2174/138920312803582951] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 05/22/2012] [Accepted: 05/23/2012] [Indexed: 12/21/2022]
Abstract
This review will summarize and discuss the current biological understanding of the motile eukaryotic flagellum,
as posed out by recent advances enabled by post-genomics and proteomics approaches. The organelle, which is crucial
for motility, survival, differentiation, reproduction, division and feeding, among other activities, of many eukaryotes,
is a great example of a natural nanomachine assembled mostly by proteins (around 350-650 of them) that have been conserved
throughout eukaryotic evolution. Flagellar proteins are discussed in terms of their arrangement on to the axoneme,
the canonical “9+2” microtubule pattern, and also motor and sensorial elements that have been detected by recent proteomic
analyses in organisms such as Chlamydomonas reinhardtii, sea urchin, and trypanosomatids. Such findings can be
remarkably matched up to important discoveries in vertebrate and mammalian types as diverse as sperm cells, ciliated
kidney epithelia, respiratory and oviductal cilia, and neuro-epithelia, among others. Here we will focus on some exciting
work regarding eukaryotic flagellar proteins, particularly using the flagellar proteome of C. reinhardtii as a reference map
for exploring motility in function, dysfunction and pathogenic flagellates. The reference map for the eukaryotic flagellar
proteome consists of 652 proteins that include known structural and intraflagellar transport (IFT) proteins, less well-characterized
signal transduction proteins and flagellar associated proteins (FAPs), besides almost two hundred unannotated
conserved proteins, which lately have been the subject of intense investigation and of our present examination.
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Affiliation(s)
- Michely C Diniz
- Programa de Pós-Graduação em Biotecnologia-RENORBIO-Rede Nordeste de Biotecnologia, Universidade Estadual do Ceará-UECE, Av. Paranjana, 1700, Campus do Itaperi, Fortaleza, CE 60740-000 Brasil
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16
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The DPY-30 domain and its flanking sequence mediate the assembly and modulation of flagellar radial spoke complexes. Mol Cell Biol 2012; 32:4012-24. [PMID: 22851692 DOI: 10.1128/mcb.06602-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
RIIa is known as the dimerization and docking (D/D) domain of the cyclic AMP (cAMP)-dependent protein kinase. However, numerous molecules, including radial spoke protein 2 (RSP2) in Chlamydomonas flagella, also contain an RIIa or a similar DPY-30 domain. To elucidate new roles of D/D domain-containing proteins, we investigated a panel of RSP2 mutants. An RSP2 mutant had paralyzed flagella defective in RSP2 and multiple subunits near the spokehead. New transgenic strains lacking only the DPY-30 domain in RSP2 were also paralyzed. In contrast, motility was restored in strains that lacked only RSP2's calmodulin-binding C-terminal region. These cells swam normally in dim light but could not maintain typical swimming trajectories under bright illumination. In both deletion transgenic strains, the subunits near the spokehead were restored, but their firm attachment to the spokestalk required the DPY-30 domain. We postulate that the DPY-30-helix dimer is a conserved two-prong linker, required for normal motility, organizing duplicated subunits in the radial spoke stalk and formation of a symmetrical spokehead. Further, the dispensable calmodulin-binding region appears to fine-tune the spokehead for regulation of "steering" motility in the green algae. Thus, in general, D/D domains may function to localize molecular modules for both the assembly and modulation of macromolecular complexes.
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17
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O'Toole ET, Giddings TH, Porter ME, Ostrowski LE. Computer-assisted image analysis of human cilia and Chlamydomonas flagella reveals both similarities and differences in axoneme structure. Cytoskeleton (Hoboken) 2012; 69:577-90. [PMID: 22573610 DOI: 10.1002/cm.21035] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 04/20/2012] [Accepted: 04/23/2012] [Indexed: 01/11/2023]
Abstract
In the past decade, investigations from several different fields have revealed the critical role of cilia in human health and disease. Because of the highly conserved nature of the basic axonemal structure, many different model systems have proven useful for the study of ciliopathies, especially the unicellular, biflagellate green alga Chlamydomonas reinhardtii. Although the basic axonemal structure of cilia and flagella is highly conserved, these organelles often perform specialized functions unique to the cell or tissue in which they are found. These differences in function are likely reflected in differences in structural organization. In this work, we directly compare the structure of isolated axonemes from human cilia and Chlamydomonas flagella to identify similarities and differences that potentially play key roles in determining their functionality. Using transmission electron microscopy and 2D image averaging techniques, our analysis has confirmed the overall structural similarity between these two species, but also revealed clear differences in the structure of the outer dynein arms, the central pair projections, and the radial spokes. We also show how the application of 2D image averaging can clarify the underlying structural defects associated with primary ciliary dyskinesia (PCD). Overall, our results document the remarkable similarity between these two structures separated evolutionarily by over a billion years, while highlighting several significant differences, and demonstrate the potential of 2D image averaging to improve the diagnosis and understanding of PCD.
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Affiliation(s)
- Eileen T O'Toole
- Boulder Laboratory for 3D Electron Microscopy of Cells, Department of MCD Biology, University of Colorado, Boulder, Colorado, USA
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18
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Kohno T, Wakabayashi KI, Diener DR, Rosenbaum JL, Kamiya R. Subunit interactions within the Chlamydomonas flagellar spokehead. Cytoskeleton (Hoboken) 2011; 68:237-46. [PMID: 21391306 DOI: 10.1002/cm.20507] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 02/08/2011] [Indexed: 11/10/2022]
Abstract
The radial spoke (RS)/central pair (CP) system in cilia and flagella plays an essential role in the regulation of force generation by dynein, the motor protein that drives cilia/flagella movements. Mechanical and mechanochemicl interactions between the CP and the distal part of the RS, the spokehead, should be crucial for this control; however, the details of interaction are totally unknown. As an initial step toward an understanding of the RS-CP interaction, we examined the protein-protein interactions between the five spokehead proteins (radial spoke protein (RSP)1, RSP4, RSP6, RSP9, and RSP10) and three spoke stalk proteins (RSP2, RSP5, and RSP23), all expressed as recombinant proteins. Three of them were shown to have physiological activities by electroporation-mediated protein delivery into mutants deficient in the respective proteins. Glutathione S-transferase pulldown assays in vitro detected interactions in 10 out of 64 pairs of recombinants. In addition, chemical crosslinking of axonemes using five reagents detected seven kinds of interactions between the RS subunits in situ. Finally, in the mixture of the recombinant spokehead subunits, RSP1, RSP4, RSP6, and RSP9 formed a 7-10S complex as detected by sucrose density gradient centrifugation. It may represent a partial assembly of the spokehead. From these results, we propose a model of interactions taking place between the spokehead subunits.
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Affiliation(s)
- Takahiro Kohno
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
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19
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Wei M, Sivadas P, Owen HA, Mitchell DR, Yang P. Chlamydomonas mutants display reversible deficiencies in flagellar beating and axonemal assembly. Cytoskeleton (Hoboken) 2010; 67:71-80. [PMID: 20169531 PMCID: PMC2835312 DOI: 10.1002/cm.20422] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Accepted: 10/14/2009] [Indexed: 11/12/2022]
Abstract
Axonemal complexes in flagella are largely prepackaged in the cell body. As such, one mutation often results in the absence of the co-assembled components and permanent motility deficiencies. For example, a Chlamydomonas mutant defective in RSP4 in the radial spoke (RS), which is critical for bend propagation, has paralyzed flagella that also lack the paralogue RSP6 and three additional RS proteins. Intriguingly, recent studies showed that several mutant strains contain a mixed population of swimmers and paralyzed cells despite their identical genetic background. Here we report a cause underlying these variations. Two new mutants lacking RSP6 swim processively and other components appear normally assembled in early log phase indicating that, unlike RSP4, this paralogue is dispensable. However, swimmers cannot maintain the typical helical trajectory and reactivated cell models tend to spin. Interestingly the motile fraction and the spokehead content dwindle during stationary phase. These results suggest that (1) intact RS is critical for maintaining the rhythm of oscillatory beating and thus the helical trajectory; (2) assembly of the axonemal complex with subtle defects is less efficient and the inefficiency is accentuated in compromised conditions, leading to reversible dyskinesia. Consistently, several organisms only possess one RSP4/6 gene. Gene duplication in Chlamydomonas enhances RS assembly to maintain optimal motility in various environments.
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Affiliation(s)
- Mei Wei
- Department of Biological Sciences, Marquette University, 530 N. 15 St. Milwaukee, WI 53233
| | - Priyanka Sivadas
- Department of Biological Sciences, Marquette University, 530 N. 15 St. Milwaukee, WI 53233
| | - Heather A. Owen
- Department of Biological Sciences, University of Wisconsin-Milwaukee, 3209 N. Maryland Ave, Milwaukee, WI 53211
| | - David R. Mitchell
- Department of Cell and Developmental Biology, Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, 530 N. 15 St. Milwaukee, WI 53233
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20
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Leigh MW, Pittman JE, Carson JL, Ferkol TW, Dell SD, Davis SD, Knowles MR, Zariwala MA. Clinical and genetic aspects of primary ciliary dyskinesia/Kartagener syndrome. Genet Med 2009; 11:473-87. [PMID: 19606528 PMCID: PMC3739704 DOI: 10.1097/gim.0b013e3181a53562] [Citation(s) in RCA: 282] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Primary ciliary dyskinesia is a genetically heterogeneous disorder of motile cilia. Most of the disease-causing mutations identified to date involve the heavy (dynein axonemal heavy chain 5) or intermediate(dynein axonemal intermediate chain 1) chain dynein genes in ciliary outer dynein arms, although a few mutations have been noted in other genes. Clinical molecular genetic testing for primary ciliary dyskinesia is available for the most common mutations. The respiratory manifestations of primary ciliary dyskinesia (chronic bronchitis leading to bronchiectasis, chronic rhino-sinusitis, and chronic otitis media)reflect impaired mucociliary clearance owing to defective axonemal structure. Ciliary ultrastructural analysis in most patients (>80%) reveals defective dynein arms, although defects in other axonemal components have also been observed. Approximately 50% of patients with primary ciliary dyskinesia have laterality defects (including situs inversus totalis and, less commonly, heterotaxy, and congenital heart disease),reflecting dysfunction of embryological nodal cilia. Male infertility is common and reflects defects in sperm tail axonemes. Most patients with primary ciliary dyskinesia have a history of neonatal respiratory distress, suggesting that motile cilia play a role in fluid clearance during the transition from a fetal to neonatal lung. Ciliopathies involving sensory cilia, including autosomal dominant or recessive polycystic kidney disease, Bardet-Biedl syndrome, and Alstrom syndrome, may have chronic respiratory symptoms and even bronchiectasis suggesting clinical overlap with primary ciliary dyskinesia.
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Affiliation(s)
- Margaret W. Leigh
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Jessica E. Pittman
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Johnny L. Carson
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Thomas W. Ferkol
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA
| | - Sharon D. Dell
- Child Health Evaluative Sciences, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Stephanie D. Davis
- Department of Pediatrics, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Michael R. Knowles
- Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Maimoona A. Zariwala
- Department of Pathology/Lab Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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21
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Castleman VH, Romio L, Chodhari R, Hirst RA, de Castro SC, Parker KA, Ybot-Gonzalez P, Emes RD, Wilson SW, Wallis C, Johnson CA, Herrera RJ, Rutman A, Dixon M, Shoemark A, Bush A, Hogg C, Gardiner RM, Reish O, Greene ND, O'Callaghan C, Purton S, Chung EM, Mitchison HM. Mutations in radial spoke head protein genes RSPH9 and RSPH4A cause primary ciliary dyskinesia with central-microtubular-pair abnormalities. Am J Hum Genet 2009; 84:197-209. [PMID: 19200523 DOI: 10.1016/j.ajhg.2009.01.011] [Citation(s) in RCA: 248] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 12/22/2008] [Accepted: 01/08/2009] [Indexed: 10/21/2022] Open
Abstract
Primary ciliary dyskinesia (PCD) is a genetically heterogeneous inherited disorder arising from dysmotility of motile cilia and sperm. This is associated with a variety of ultrastructural defects of the cilia and sperm axoneme that affect movement, leading to clinical consequences on respiratory-tract mucociliary clearance and lung function, fertility, and left-right body-axis determination. We performed whole-genome SNP-based linkage analysis in seven consanguineous families with PCD and central-microtubular-pair abnormalities. This identified two loci, in two families with intermittent absence of the central-pair structure (chromosome 6p21.1, Zmax 6.7) and in five families with complete absence of the central pair (chromosome 6q22.1, Zmax 7.0). Mutations were subsequently identified in two positional candidate genes, RSPH9 on chromosome 6p21.1 and RSPH4A on chromosome 6q22.1. Haplotype analysis identified a common ancestral founder effect RSPH4A mutation present in UK-Pakistani pedigrees. Both RSPH9 and RSPH4A encode protein components of the axonemal radial spoke head. In situ hybridization of murine Rsph9 shows gene expression restricted to regions containing motile cilia. Investigation of the effect of knockdown or mutations of RSPH9 orthologs in zebrafish and Chlamydomonas indicate that radial spoke head proteins are important in maintaining normal movement in motile, "9+2"-structure cilia and flagella. This effect is rescued by reintroduction of gene expression for restoration of a normal beat pattern in zebrafish. Disturbance in function of these genes was not associated with defects in left-right axis determination in humans or zebrafish.
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22
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Abstract
Flagella are sensory organelles that interact with the environment through signal transduction and gene expression networks. We used microarray profiling to examine gene regulation associated with flagellar length change in the green alga Chlamydomonas reinhardtii. Microarrays were probed with fluorescently labeled cDNAs synthesized from RNA extracted from cells before and during flagellar assembly or disassembly. Evaluation of the gene expression profiles identified >100 clones showing at least a twofold change in expression during flagellar length changes. Products of these genes are associated not only with flagellar structure and motility but also with other cellular responses, including signal transduction and metabolism. Expression of specific genes from each category was further characterized at higher resolution by using quantitative real-time PCR (qRT-PCR). Analysis and comparison of the gene expression profiles coupled to flagellar assembly and disassembly revealed that each process involves a new and uncharacterized whole-cell response to flagellar length changes. This analysis lays the groundwork for a more comprehensive understanding of the cellular and molecular networks regulating flagellar length changes.
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23
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Yang P, Diener DR, Yang C, Kohno T, Pazour GJ, Dienes JM, Agrin NS, King SM, Sale WS, Kamiya R, Rosenbaum JL, Witman GB. Radial spoke proteins of Chlamydomonas flagella. J Cell Sci 2006; 119:1165-74. [PMID: 16507594 PMCID: PMC1973137 DOI: 10.1242/jcs.02811] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The radial spoke is a ubiquitous component of '9+2' cilia and flagella, and plays an essential role in the control of dynein arm activity by relaying signals from the central pair of microtubules to the arms. The Chlamydomonas reinhardtii radial spoke contains at least 23 proteins, only 8 of which have been characterized at the molecular level. Here, we use mass spectrometry to identify 10 additional radial spoke proteins. Many of the newly identified proteins in the spoke stalk are predicted to contain domains associated with signal transduction, including Ca2+-, AKAP- and nucleotide-binding domains. This suggests that the spoke stalk is both a scaffold for signaling molecules and itself a transducer of signals. Moreover, in addition to the recently described HSP40 family member, a second spoke stalk protein is predicted to be a molecular chaperone, implying that there is a sophisticated mechanism for the assembly of this large complex. Among the 18 spoke proteins identified to date, at least 12 have apparent homologs in humans, indicating that the radial spoke has been conserved throughout evolution. The human genes encoding these proteins are candidates for causing primary ciliary dyskinesia, a severe inherited disease involving missing or defective axonemal structures, including the radial spokes.
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Affiliation(s)
- Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA.
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24
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Smith EF, Yang P. The radial spokes and central apparatus: mechano-chemical transducers that regulate flagellar motility. ACTA ACUST UNITED AC 2004; 57:8-17. [PMID: 14648553 PMCID: PMC1950942 DOI: 10.1002/cm.10155] [Citation(s) in RCA: 198] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Elizabeth F Smith
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA.
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25
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Qin H, Diener DR, Geimer S, Cole DG, Rosenbaum JL. Intraflagellar transport (IFT) cargo: IFT transports flagellar precursors to the tip and turnover products to the cell body. ACTA ACUST UNITED AC 2004; 164:255-66. [PMID: 14718520 PMCID: PMC2172340 DOI: 10.1083/jcb.200308132] [Citation(s) in RCA: 270] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Intraflagellar transport (IFT) is the bidirectional movement of multisubunit protein particles along axonemal microtubules and is required for assembly and maintenance of eukaryotic flagella and cilia. One posited role of IFT is to transport flagellar precursors to the flagellar tip for assembly. Here, we examine radial spokes, axonemal subunits consisting of 22 polypeptides, as potential cargo for IFT. Radial spokes were found to be partially assembled in the cell body, before being transported to the flagellar tip by anterograde IFT. Fully assembled radial spokes, detached from axonemal microtubules during flagellar breakdown or turnover, are removed from flagella by retrograde IFT. Interactions between IFT particles, motors, radial spokes, and other axonemal proteins were verified by coimmunoprecipitation of these proteins from the soluble fraction of Chlamydomonas flagella. These studies indicate that one of the main roles of IFT in flagellar assembly and maintenance is to transport axonemal proteins in and out of the flagellum.
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Affiliation(s)
- Hongmin Qin
- MCDB Dept., Yale University, New Haven, CT 06520, USA
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26
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Kathir P, LaVoie M, Brazelton WJ, Haas NA, Lefebvre PA, Silflow CD. Molecular map of the Chlamydomonas reinhardtii nuclear genome. EUKARYOTIC CELL 2003; 2:362-79. [PMID: 12684385 PMCID: PMC154841 DOI: 10.1128/ec.2.2.362-379.2003] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2002] [Accepted: 12/10/2002] [Indexed: 11/20/2022]
Abstract
We have prepared a molecular map of the Chlamydomonas reinhardtii genome anchored to the genetic map. The map consists of 264 markers, including sequence-tagged sites (STS), scored by use of PCR and agarose gel electrophoresis, and restriction fragment length polymorphism markers, scored by use of Southern blot hybridization. All molecular markers tested map to one of the 17 known linkage groups of C. reinhardtii. The map covers approximately 1,000 centimorgans (cM). Any position on the C. reinhardtii genetic map is, on average, within 2 cM of a mapped molecular marker. This molecular map, in combination with the ongoing mapping of bacterial artificial chromosome (BAC) clones and the forthcoming sequence of the C. reinhardtii nuclear genome, should greatly facilitate isolation of genes of interest by using positional cloning methods. In addition, the presence of easily assayed STS markers on each arm of each linkage group should be very useful in mapping new mutations in preparation for positional cloning.
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Affiliation(s)
- Pushpa Kathir
- Department of Genetics, University of Minnesota, St. Paul, Minnesota, USA
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27
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Kang Y, Mitchell DR. An intronic enhancer is required for deflagellation-induced transcriptional regulation of a Chlamydomonas reinhardtii dynein gene. Mol Biol Cell 1998; 9:3085-94. [PMID: 9802898 PMCID: PMC25592 DOI: 10.1091/mbc.9.11.3085] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Chlamydomonas reinhardtii flagellar regeneration is accompanied by rapid induction of genes encoding a large set of flagellar structural components and provides a model system to study coordinate gene regulation and organelle assembly. After deflagellation, the abundance of a 70-kDa flagellar dynein intermediate chain (IC70, encoded by ODA6) mRNA increases approximately fourfold within 40 min and returns to predeflagellation levels by approximately 90 min. We show by nuclear run-on that this increase results, in part, from increased rates of transcription. To localize cis induction elements, we created an IC70 minigene and measured accumulation, in C. reinhardtii, of transcripts from the endogenous gene and from introduced promoter deletion constructs. Clones containing 416 base pairs (bp) of 5'- and 2 kilobases (kb) of 3'-flanking region retained all sequences necessary for a normal pattern of mRNA abundance change after deflagellation. Extensive 5'- and 3'- flanking region deletions, which removed multiple copies of a proposed deflagellation-response element (the tub box), did not eliminate induction, and the IC70 5'-flanking region alone did not confer deflagellation responsiveness to a promoterless arylsulfatase (ARS) gene. Instead, an intron in the IC70 gene 5'-untranslated region was found to contain the deflagellation response element. These results suggest that the tub box does not play an essential role in deflagellation-induced transcriptional regulation of this dynein gene.
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Affiliation(s)
- Y Kang
- Department of Anatomy and Cell Biology, State University of New York Health Science Center, Syracuse, New York 13210, USA
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28
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Gera JF, Baker EJ. Deadenylation-dependent and -independent decay pathways for alpha1-tubulin mRNA in Chlamydomonas reinhardtii. Mol Cell Biol 1998; 18:1498-505. [PMID: 9488466 PMCID: PMC108864 DOI: 10.1128/mcb.18.3.1498] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/1997] [Accepted: 12/15/1997] [Indexed: 02/06/2023] Open
Abstract
The alpha- and beta-tubulin mRNAs of Chlamydomonas reinhardtii exhibit different half-lives under different conditions: when expressed constitutively, they degrade with half-lives of about 1 h, whereas when induced by deflagellation, they degrade with half-lives of only 10 to 15 min. To investigate the decay pathway(s) used under these two conditions, an alpha1-tubulin gene construct which included an insert of 30 guanidylate residues within the 3' untranslated region was introduced into cells. This transgene was efficiently expressed in stably transformed cells, and the mRNA exhibited constitutive and postinduction half-lives like those of the alpha1-tubulin mRNA. Northern blot analysis revealed the occurrence of a 3' RNA fragment derived from the poly(G)-containing alpha1-tubulin transcripts. The 3' fragment was shown to accumulate as full-length mRNA disappeared in actinomycin D-treated cells, indicating a precursor-product relationship. Insertion of a second poly(G) tract upstream of the first resulted in accumulation of only a longer 3' fragment, suggesting that the decay intermediate is generated by 5'-to-3' exonucleolytic digestion. A translational requirement for generation of the 3' fragment was demonstrated by experiments in which cells were deflagellated in the presence of cycloheximide. Analysis of fragment poly(A) length revealed that the fragments were, at most, oligoadenylated in nondeflagellated cells but had a long poly(A) tail in deflagellated cells. These findings suggest that the oligoadenylated fragment is a decay intermediate in a deadenylation-dependent, constitutive degradation pathway and that the requirement for deadenylation is bypassed in deflagellated cells. This represents the first example in which a single transcript has been shown to be targeted to different decay pathways under different cellular conditions.
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Affiliation(s)
- J F Gera
- Cell and Molecular Biology Graduate Program, University of Nevada, Reno 89557, USA
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29
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Gingras D, White D, Garin J, Cosson J, Huitorel P, Zingg H, Cibert C, Gagnon C. Molecular cloning and characterization of a radial spoke head protein of sea urchin sperm axonemes: involvement of the protein in the regulation of sperm motility. Mol Biol Cell 1998; 9:513-22. [PMID: 9450971 PMCID: PMC25281 DOI: 10.1091/mbc.9.2.513] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Monoclonal antibodies raised against axonemal proteins of sea urchin spermatozoa have been used to study regulatory mechanisms involved in flagellar motility. Here, we report that one of these antibodies, monoclonal antibody D-316, has an unusual perturbating effect on the motility of sea urchin sperm models; it does not affect the beat frequency, the amplitude of beating or the percentage of motile sperm models, but instead promotes a marked transformation of the flagellar beating pattern which changes from a two-dimensional to a three-dimensional type of movement. On immunoblots of axonemal proteins separated by SDS-PAGE, D-316 recognized a single polypeptide of 90 kDa. This protein was purified following its extraction by exposure of axonemes to a brief heat treatment at 40 degrees C. The protein copurified and coimmunoprecipitated with proteins of 43 and 34 kDa, suggesting that it exists as a complex in its native form. Using D-316 as a probe, a full-length cDNA clone encoding the 90-kDa protein was obtained from a sea urchin cDNA library. The sequence predicts a highly acidic (pI = 4.0) protein of 552 amino acids with a mass of 62,720 Da (p63). Comparison with protein sequences in databases indicated that the protein is related to radial spoke proteins 4 and 6 (RSP4 and RSP6) of Chlamydomonas reinhardtii, which share 37% and 25% similarity, respectively, with p63. However, the sea urchin protein possesses structural features distinct from RSP4 and RSP6, such as the presence of three major acidic stretches which contains 25, 17, and 12 aspartate and glutamate residues of 34-, 22-, and 14-amino acid long stretches, respectively, that are predicted to form alpha-helical coiled-coil secondary structures. These results suggest a major role for p63 in the maintenance of a planar form of sperm flagellar beating and provide new tools to study the function of radial spoke heads in more evolved species.
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Affiliation(s)
- D Gingras
- Urology Research Laboratory, Royal Victoria Hospital, McGill University, Montreal H3A 1A1, Quebec, Canada.
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Kozminski KG, Beech PL, Rosenbaum JL. The Chlamydomonas kinesin-like protein FLA10 is involved in motility associated with the flagellar membrane. J Biophys Biochem Cytol 1995; 131:1517-27. [PMID: 8522608 PMCID: PMC2120669 DOI: 10.1083/jcb.131.6.1517] [Citation(s) in RCA: 446] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The Chlamydomonas FLA10 gene was shown to encode a flagellar kinesin-like protein (Walther, Z., M. Vashishtha, and J.L. Hall. 1994. J. Cell Biol. 126:175-188). By using a temperature-sensitive allele of FLA10, we have determined that the FLA10 protein is necessary for both the bidirectional movement of polystyrene beads on the flagellar membrane and intraflagellar transport (IFT), the bidirectional movement of granule-like particles beneath the flagellar membrane (Kozminski, K.G., K.A. Johnson, P. Forscher, and J.L. Rosenbaum. 1993. Proc. Natl. Acad. Sci. (USA). 90:5519-5523). In addition, we have correlated the presence and position of the IFT particles visualized by light microscopy with that of the electron dense complexes (rafts) observed beneath the flagellar membrane by electron microscopy. A role for FLA10 in submembranous or flagellar surface motility is also strongly supported by the immunolocalization of FLA10 to the region between the axonemal outer doublet microtubules and the flagellar membrane.
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Affiliation(s)
- K G Kozminski
- Department of Biology, Yale University, New Haven, Connecticut 06511, USA
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Sequences controlling transcription of the Chlamydomonas reinhardtii beta 2-tubulin gene after deflagellation and during the cell cycle. Mol Cell Biol 1994. [PMID: 8035797 DOI: 10.1128/mcb.14.8.5165] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Chlamydomonas reinhardtii, transcripts from the beta 2-tubulin gene (tubB2), as well as those from other tubulin-encoding genes, accumulate immediately after flagellar excision as well as at a specific time in the cell cycle. Control of tubB2 transcript accumulation following deflagellation is regulated, at least partially, at the transcriptional level. We have fused the tubB2 promoter to the arylsulfatase (ars) reporter gene, introduced this construct into C. reinhardtii, and compared expression of the chimeric gene with that of the endogenous tubB2 gene. After flagellar excision, transcripts from the tubB2/ars chimeric gene accumulate with kinetics similar to those of transcripts from the endogenous tubB2 gene. The tubB2/ars transcripts also accumulate in a cell cycle-specific manner; however, chimeric transcripts are more abundant earlier in the cell cycle than the endogenous tubB2 transcripts. To elucidate transcriptional control of tubB2, we have mutated or removed sequences in the tubB2 promoter and examined the effect on transcription. The tubB2 promoter shares features with the promoters of other tubulin-encoding genes; these include a GC-rich region between the TATA box and the transcription initiation site and multiple copies of a 10-bp sequence motif that we call the tub box. The tubB2 gene contains seven tub box motifs. Changing the GC-rich region to an AT-rich region or removing three of the seven tub box motifs did not significantly affect transcription of the chimeric gene. However, removing four or five tub box motifs prevented increased transcription following deflagellation and diminished cell cycle-regulated transcription from the tubB2 promoter.
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Davies JP, Grossman AR. Sequences controlling transcription of the Chlamydomonas reinhardtii beta 2-tubulin gene after deflagellation and during the cell cycle. Mol Cell Biol 1994; 14:5165-74. [PMID: 8035797 PMCID: PMC359035 DOI: 10.1128/mcb.14.8.5165-5174.1994] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In Chlamydomonas reinhardtii, transcripts from the beta 2-tubulin gene (tubB2), as well as those from other tubulin-encoding genes, accumulate immediately after flagellar excision as well as at a specific time in the cell cycle. Control of tubB2 transcript accumulation following deflagellation is regulated, at least partially, at the transcriptional level. We have fused the tubB2 promoter to the arylsulfatase (ars) reporter gene, introduced this construct into C. reinhardtii, and compared expression of the chimeric gene with that of the endogenous tubB2 gene. After flagellar excision, transcripts from the tubB2/ars chimeric gene accumulate with kinetics similar to those of transcripts from the endogenous tubB2 gene. The tubB2/ars transcripts also accumulate in a cell cycle-specific manner; however, chimeric transcripts are more abundant earlier in the cell cycle than the endogenous tubB2 transcripts. To elucidate transcriptional control of tubB2, we have mutated or removed sequences in the tubB2 promoter and examined the effect on transcription. The tubB2 promoter shares features with the promoters of other tubulin-encoding genes; these include a GC-rich region between the TATA box and the transcription initiation site and multiple copies of a 10-bp sequence motif that we call the tub box. The tubB2 gene contains seven tub box motifs. Changing the GC-rich region to an AT-rich region or removing three of the seven tub box motifs did not significantly affect transcription of the chimeric gene. However, removing four or five tub box motifs prevented increased transcription following deflagellation and diminished cell cycle-regulated transcription from the tubB2 promoter.
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Affiliation(s)
- J P Davies
- Department of Plant Biology, Carnegie Institution of Washington, Stanford, California 94305
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Bernstein M, Beech PL, Katz SG, Rosenbaum JL. A new kinesin-like protein (Klp1) localized to a single microtubule of the Chlamydomonas flagellum. J Biophys Biochem Cytol 1994; 125:1313-26. [PMID: 8207060 PMCID: PMC2290928 DOI: 10.1083/jcb.125.6.1313] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The kinesin superfamily of mechanochemical proteins has been implicated in a wide variety of cellular processes. We have begun studies of kinesins in the unicellular biflagellate alga, Chlamydomonas reinhardtii. A full-length cDNA, KLP1, has been cloned and sequenced, and found to encode a new member of the kinesin superfamily. An antibody was raised against the nonconserved tail region of the Klp1 protein, and it was used to probe for Klp1 in extracts of isolated flagella and in situ. Immunofluorescence of whole cells indicated that Klp1 was present in both the flagella and cell bodies. In wild-type flagella, Klp1 was found tightly to the axoneme; immunogold labeling of wild-type axonemal whole mounts showed that Klp1 was restricted to one of the two central pair microtubules at the core of the axoneme. Klp1 was absent from the flagella of mutants lacking the central pair microtubules, but was present in mutant flagella from pf16 cells, which contain an unstable C1 microtubule, indicating that Klp1 was bound to the C2 central pair microtubule. Localization of Klp1 to the C2 microtubule was confirmed by immunogold labeling of negatively stained and thin-sectioned axonemes. These findings suggest that Klp1 may play a role in rotation or twisting of the central pair microtubules.
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Affiliation(s)
- M Bernstein
- Department of Biology, Yale University, New Haven, Connecticut 06520-8103
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Diener DR, Ang LH, Rosenbaum JL. Assembly of flagellar radial spoke proteins in Chlamydomonas: identification of the axoneme binding domain of radial spoke protein 3. J Biophys Biochem Cytol 1993; 123:183-90. [PMID: 8408197 PMCID: PMC2119812 DOI: 10.1083/jcb.123.1.183] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Radial spokes of the eukaryotic flagellum extend from the A tubule of each outer doublet microtubule toward the central pair microtubules. In the paralyzed flagella mutant of Chlamydomonas pf14, a mutation in the gene for one of 17 polypeptides that comprise the radial spokes results in flagella that lack all 17 spoke components. The defective gene product, radial spoke protein 3 (RSP3), is, therefore, pivotal to the assembly of the entire spoke and may attach the spoke to the axoneme. We have synthesized RSP3 in vitro and assayed its binding to axonemes from pf14 cells to determine if RSP3 can attach to spokeless axonemes. In vitro, RSP3 binds to pf14 axonemes, but not to wild-type axonemes or microtubules polymerized from purified chick brain tubulin. The sole axoneme binding domain of RSP3 is located within amino acids 1-85 of the 516 amino acid protein; deletion of these amino acids abolishes binding by RSP3. Fusion of amino acids 1-85 or 42-85 to an unrelated protein confers complete or partial binding activity, respectively, to the fusion protein. Transformation of pf14 cells with mutagenized RSP3 genes indicates that amino acids 18-87 of RSP3 are important to its function, but that the carboxy-terminal 140 amino acids can be deleted with little effect on radial spoke assembly or flagellar motility.
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Affiliation(s)
- D R Diener
- Department of Biology, Yale University, New Haven, Connecticut 06511
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New nucleotide sequence data on the EMBL File Server. Nucleic Acids Res 1992; 20:6429-38. [PMID: 1475213 PMCID: PMC334548 DOI: 10.1093/nar/20.23.6429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Abstract
During mating of the alga Chlamydomonas, two biflagellate cells fuse to form a single quadriflagellate cell that contains two nuclei and a common cytoplasm. We have used this cell fusion during mating to transfer unassembled flagellar components from the cytoplasm of one Chlamydomonas cell into that of another in order to study in vivo the polarity of flagellar assembly. In the first series of experiments, sites of tubulin addition onto elongating flagellar axonemes were determined. Donor cells that had two full-length flagella and were expressing an epitope-tagged alpha-tubulin construct were mated (fused) with recipient cells that had two half-length flagella. Outgrowth of the shorter pair of flagella followed, using a common pool of precursors that now included epitope-tagged tubulin, resulting in quadriflagellates with four full-length flagella. Immunofluorescence and immunoelectron microscopy using an antiepitope antibody showed that both the outer doublet and central pair microtubules of the recipient cells' flagellar axonemes elongate solely by addition of new subunits at their distal ends. In a separate series of experiments, the polarity of assembly of a class of axonemal microtubule-associated structures, the radial spokes, was determined. Wild-type donor cells that had two full-length, motile flagella were mated with paralyzed recipient cells that had two full-length, radial spokeless flagella. Within 90 min after cell fusion, the previously paralyzed flagella became motile. Immunofluorescence microscopy using specific antiradial spoke protein antisera showed that radial spoke proteins appeared first at the tips of spokeless axonemes and gradually assembled toward the bases. Together, these results suggest that both tubulin and radial spoke proteins are transported to the tip of the flagellum before their assembly into flagellar structure.
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Affiliation(s)
- K A Johnson
- Department of Biology, Yale University, New Haven, Connecticut 06511
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