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Walker DR, Jara KA, Rolland AD, Brooks C, Hare W, Swansiger AK, Reardon PN, Prell JS, Barbar EJ. Linker Length Drives Heterogeneity of Multivalent Complexes of Hub Protein LC8 and Transcription Factor ASCIZ. Biomolecules 2023; 13:404. [PMID: 36979339 PMCID: PMC10046861 DOI: 10.3390/biom13030404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/08/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
LC8, a ubiquitous and highly conserved hub protein, binds over 100 proteins involved in numerous cellular functions, including cell death, signaling, tumor suppression, and viral infection. LC8 binds intrinsically disordered proteins (IDPs), and although several of these contain multiple LC8 binding motifs, the effects of multivalency on complex formation are unclear. Drosophila ASCIZ has seven motifs that vary in sequence and inter-motif linker lengths, especially within subdomain QT2-4 containing the second, third, and fourth LC8 motifs. Using isothermal-titration calorimetry, analytical-ultracentrifugation, and native mass-spectrometry of QT2-4 variants, with methodically deactivated motifs, we show that inter-motif spacing and specific motif sequences combine to control binding affinity and compositional heterogeneity of multivalent duplexes. A short linker separating strong and weak motifs results in stable duplexes but forms off-register structures at high LC8 concentrations. Contrastingly, long linkers engender lower cooperativity and heterogeneous complexation at low LC8 concentrations. Accordingly, two-mers, rather than the expected three-mers, dominate negative-stain electron-microscopy images of QT2-4. Comparing variants containing weak-strong and strong-strong motif combinations demonstrates sequence also regulates IDP/LC8 assembly. The observed trends persist for trivalent ASCIZ subdomains: QT2-4, with long and short linkers, forms heterogeneous complexes, whereas QT4-6, with similar mid-length linkers, forms homogeneous complexes. Implications of linker length variations for function are discussed.
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Affiliation(s)
- Douglas R. Walker
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Kayla A. Jara
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Amber D. Rolland
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Coban Brooks
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Wendy Hare
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Andrew K. Swansiger
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Patrick N. Reardon
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
- NMR Facility, Oregon State University, Corvallis, OR 97331, USA
| | - James S. Prell
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
- Materials Science Institute, University of Oregon, Eugene, OR 97403, USA
| | - Elisar J. Barbar
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
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2
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Pereira R, Sousa M. Morphological and Molecular Bases of Male Infertility: A Closer Look at Sperm Flagellum. Genes (Basel) 2023; 14:genes14020383. [PMID: 36833310 PMCID: PMC9956255 DOI: 10.3390/genes14020383] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/19/2023] [Accepted: 01/25/2023] [Indexed: 02/04/2023] Open
Abstract
Infertility is a major health problem worldwide without an effective therapy or cure. It is estimated to affect 8-12% of couples in the reproductive age group, equally affecting both genders. There is no single cause of infertility, and its knowledge is still far from complete, with about 30% of infertile couples having no cause identified (named idiopathic infertility). Among male causes of infertility, asthenozoospermia (i.e., reduced sperm motility) is one of the most observed, being estimated that more than 20% of infertile men have this condition. In recent years, many researchers have focused on possible factors leading to asthenozoospermia, revealing the existence of many cellular and molecular players. So far, more than 4000 genes are thought to be involved in sperm production and as regulators of different aspects of sperm development, maturation, and function, and all can potentially cause male infertility if mutated. In this review, we aim to give a brief overview of the typical sperm flagellum morphology and compile some of the most relevant information regarding the genetic factors involved in male infertility, with a focus on sperm immotility and on genes related to sperm flagellum development, structure, or function.
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Affiliation(s)
- Rute Pereira
- Laboratory of Cell Biology, Department of Microscopy, ICBAS-School of Medicine and Biomedical Sciences, University of Porto, 4050-313 Porto, Portugal
- UMIB-Unit for Multidisciplinary Research in Biomedicine, ITR-Laboratory for Integrative and Translational Research in Population Health, University of Porto, 4050-313 Porto, Portugal
- Correspondence: ; Tel.: +35-1918-127-817
| | - Mário Sousa
- Laboratory of Cell Biology, Department of Microscopy, ICBAS-School of Medicine and Biomedical Sciences, University of Porto, 4050-313 Porto, Portugal
- UMIB-Unit for Multidisciplinary Research in Biomedicine, ITR-Laboratory for Integrative and Translational Research in Population Health, University of Porto, 4050-313 Porto, Portugal
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3
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Abstract
The assembly and maintenance of most cilia and eukaryotic flagella depends on intraflagellar transport (IFT), the bidirectional movement of multi-megadalton IFT trains along the axonemal microtubules. These IFT trains function as carriers, moving ciliary proteins between the cell body and the organelle. Whereas tubulin, the principal protein of cilia, binds directly to IFT particle proteins, the transport of other ciliary proteins and complexes requires adapters that link them to the trains. Large axonemal substructures, such as radial spokes, outer dynein arms and inner dynein arms, assemble in the cell body before attaching to IFT trains, using the adapters ARMC2, ODA16 and IDA3, respectively. Ciliary import of several membrane proteins involves the putative adapter tubby-like protein 3 (TULP3), whereas membrane protein export involves the BBSome, an octameric complex that co-migrates with IFT particles. Thus, cells employ a variety of adapters, each of which is substoichiometric to the core IFT machinery, to expand the cargo range of the IFT trains. This Review summarizes the individual and shared features of the known cargo adapters and discusses their possible role in regulating the transport capacity of the IFT pathway.
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Affiliation(s)
- Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
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4
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Hibbard JVK, Vázquez N, Wallingford JB. Cilia proteins getting to work - how do they commute from the cytoplasm to the base of cilia? J Cell Sci 2022; 135:jcs259444. [PMID: 36073764 PMCID: PMC9482345 DOI: 10.1242/jcs.259444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cilia are multifunctional organelles that originated with the last eukaryotic common ancestor and play central roles in the life cycles of diverse organisms. The motile flagella that move single cells like sperm or unicellular organisms, the motile cilia on animal multiciliated cells that generate fluid flow in organs, and the immotile primary cilia that decorate nearly all cells in animals share many protein components in common, yet each also requires specialized proteins to perform their specialized functions. Despite a now-advanced understanding of how such proteins are transported within cilia, we still know very little about how they are transported from their sites of synthesis through the cytoplasm to the ciliary base. Here, we review the literature concerning this underappreciated topic in ciliary cell biology. We discuss both general mechanisms, as well as specific examples of motor-driven active transport and passive transport via diffusion-and-capture. We then provide deeper discussion of specific, illustrative examples, such as the diverse array of protein subunits that together comprise the intraflagellar transport (IFT) system and the multi-protein axonemal dynein motors that drive beating of motile cilia. We hope this Review will spur further work, shedding light not only on ciliogenesis and ciliary signaling, but also on intracellular transport in general.
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Affiliation(s)
| | | | - John B. Wallingford
- Department of Molecular Biosciences, University of Texas, Austin, TX 78751, USA
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5
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Lechtreck KF, Liu Y, Dai J, Alkhofash RA, Butler J, Alford L, Yang P. Chlamydomonas ARMC2/PF27 is an obligate cargo adapter for intraflagellar transport of radial spokes. eLife 2022; 11:74993. [PMID: 34982025 PMCID: PMC8789290 DOI: 10.7554/elife.74993] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/03/2022] [Indexed: 12/19/2022] Open
Abstract
Intraflagellar transport (IFT) carries proteins into flagella but how IFT trains interact with the large number of diverse proteins required to assemble flagella remains largely unknown. Here, we show that IFT of radial spokes in Chlamydomonas requires ARMC2/PF27, a conserved armadillo repeat protein associated with male infertility and reduced lung function. Chlamydomonas ARMC2 was highly enriched in growing flagella and tagged ARMC2 and the spoke protein RSP3 co-migrated on anterograde trains. In contrast, a cargo and an adapter of inner and outer dynein arms moved independently of ARMC2, indicating that unrelated cargoes distribute stochastically onto the IFT trains. After concomitant unloading at the flagellar tip, RSP3 attached to the axoneme whereas ARMC2 diffused back to the cell body. In armc2/pf27 mutants, IFT of radial spokes was abolished and the presence of radial spokes was limited to the proximal region of flagella. We conclude that ARMC2 is a cargo adapter required for IFT of radial spokes to ensure their assembly along flagella. ARMC2 belongs to a growing class of cargo-specific adapters that enable flagellar transport of preassembled axonemal substructures by IFT.
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Affiliation(s)
- Karl F Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, United States
| | - Yi Liu
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Jin Dai
- Department of Cellular Biology, University of Georgia, Athens, United States
| | - Rama A Alkhofash
- Department of Cellular Biology, University of Georgia, Athens, United States
| | - Jack Butler
- Department of Cellular Biology, University of Georgia, Athens, United States
| | - Lea Alford
- Division of Natural Sciences,, Oglethorpe University, Atlanta, United States
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, United States
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6
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White KA, McEntire KD, Buan NR, Robinson L, Barbar E. Charting a New Frontier Integrating Mathematical Modeling in Complex Biological Systems from Molecules to Ecosystems. Integr Comp Biol 2021; 61:2255-2266. [PMID: 34283225 DOI: 10.1093/icb/icab165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/09/2021] [Accepted: 07/16/2021] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | - Nicole R Buan
- University of Nebraska-Lincoln, Department of Biochemistry
| | | | - Elisar Barbar
- Oregon State University, Department of Biochemistry and Biophysics
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7
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Yamamoto R, Hwang J, Ishikawa T, Kon T, Sale WS. Composition and function of ciliary inner-dynein-arm subunits studied in Chlamydomonas reinhardtii. Cytoskeleton (Hoboken) 2021; 78:77-96. [PMID: 33876572 DOI: 10.1002/cm.21662] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/30/2021] [Accepted: 04/15/2021] [Indexed: 11/09/2022]
Abstract
Motile cilia (also interchangeably called "flagella") are conserved organelles extending from the surface of many animal cells and play essential functions in eukaryotes, including cell motility and environmental sensing. Large motor complexes, the ciliary dyneins, are present on ciliary outer-doublet microtubules and drive movement of cilia. Ciliary dyneins are classified into two general types: the outer dynein arms (ODAs) and the inner dynein arms (IDAs). While ODAs are important for generation of force and regulation of ciliary beat frequency, IDAs are essential for control of the size and shape of the bend, features collectively referred to as waveform. Also, recent studies have revealed unexpected links between IDA components and human diseases. In spite of their importance, studies on IDAs have been difficult since they are very complex and composed for several types of IDA motors, each unique in composition and location in the axoneme. Thanks in part to genetic, biochemical, and structural analysis of Chlamydomonas reinhardtii, we are beginning to understand the organization and function of the ciliary IDAs. In this review, we summarize the composition of Chlamydomonas IDAs particularly focusing on each subunit, and discuss the assembly, conservation, and functional role(s) of these IDA subunits. Furthermore, we raise several additional questions/challenges regarding IDAs, and discuss future perspectives of IDA studies.
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Affiliation(s)
- Ryosuke Yamamoto
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Juyeon Hwang
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Takashi Ishikawa
- Department of Biology and Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland.,Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Takahide Kon
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Winfield S Sale
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
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8
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Grossman-Haham I, Coudray N, Yu Z, Wang F, Zhang N, Bhabha G, Vale RD. Structure of the radial spoke head and insights into its role in mechanoregulation of ciliary beating. Nat Struct Mol Biol 2021; 28:20-28. [PMID: 33318704 PMCID: PMC7855469 DOI: 10.1038/s41594-020-00519-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/16/2020] [Indexed: 11/14/2022]
Abstract
Motile cilia power cell locomotion and drive extracellular fluid flow by propagating bending waves from their base to tip. The coordinated bending of cilia requires mechanoregulation by the radial spoke (RS) protein complexes and the microtubule central pair (CP). Despite their importance for ciliary motility across eukaryotes, the molecular function of the RSs is unknown. Here, we reconstituted the Chlamydomonas reinhardtii RS head that abuts the CP and determined its structure using single-particle cryo-EM to 3.1-Å resolution, revealing a flat, negatively charged surface supported by a rigid core of tightly intertwined proteins. Mutations in this core, corresponding to those involved in human ciliopathies, compromised the stability of the recombinant complex, providing a molecular basis for disease. Partially reversing the negative charge on the RS surface impaired motility in C. reinhardtii. We propose that the RS-head architecture is well-suited for mechanoregulation of ciliary beating through physical collisions with the CP.
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Affiliation(s)
- Iris Grossman-Haham
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Nicolas Coudray
- Department of Cell Biology, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Applied Bioinformatics Laboratories, New York University School of Medicine, New York, NY, USA
| | - Zanlin Yu
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Feng Wang
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Nan Zhang
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Gira Bhabha
- Department of Cell Biology, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
| | - Ronald D Vale
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
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9
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Gui M, Ma M, Sze-Tu E, Wang X, Koh F, Zhong ED, Berger B, Davis JH, Dutcher SK, Zhang R, Brown A. Structures of radial spokes and associated complexes important for ciliary motility. Nat Struct Mol Biol 2021; 28:29-37. [PMID: 33318703 PMCID: PMC7855293 DOI: 10.1038/s41594-020-00530-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/28/2020] [Indexed: 12/20/2022]
Abstract
In motile cilia, a mechanoregulatory network is responsible for converting the action of thousands of dynein motors bound to doublet microtubules into a single propulsive waveform. Here, we use two complementary cryo-EM strategies to determine structures of the major mechanoregulators that bind ciliary doublet microtubules in Chlamydomonas reinhardtii. We determine structures of isolated radial spoke RS1 and the microtubule-bound RS1, RS2 and the nexin-dynein regulatory complex (N-DRC). From these structures, we identify and build atomic models for 30 proteins, including 23 radial-spoke subunits. We reveal how mechanoregulatory complexes dock to doublet microtubules with regular 96-nm periodicity and communicate with one another. Additionally, we observe a direct and dynamically coupled association between RS2 and the dynein motor inner dynein arm subform c (IDAc), providing a molecular basis for the control of motor activity by mechanical signals. These structures advance our understanding of the role of mechanoregulation in defining the ciliary waveform.
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Affiliation(s)
- Miao Gui
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Meisheng Ma
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Erica Sze-Tu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Xiangli Wang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Fujiet Koh
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Thermo Fisher Scientific, Eindhoven, Netherlands
| | - Ellen D Zhong
- Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Bonnie Berger
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph H Davis
- Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Susan K Dutcher
- Department of Genetics, Washington University in St. Louis, St. Louis, MO, USA
| | - Rui Zhang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA.
| | - Alan Brown
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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10
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Beckers A, Adis C, Schuster-Gossler K, Tveriakhina L, Ott T, Fuhl F, Hegermann J, Boldt K, Serth K, Rachev E, Alten L, Kremmer E, Ueffing M, Blum M, Gossler A. The FOXJ1 target Cfap206 is required for sperm motility, mucociliary clearance of the airways and brain development. Development 2020; 147:dev.188052. [PMID: 32376681 DOI: 10.1242/dev.188052] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 04/15/2020] [Indexed: 12/11/2022]
Abstract
Cilia are complex cellular protrusions consisting of hundreds of proteins. Defects in ciliary structure and function, many of which have not been characterised molecularly, cause ciliopathies: a heterogeneous group of human syndromes. Here, we report on the FOXJ1 target gene Cfap206, orthologues of which so far have only been studied in Chlamydomonas and Tetrahymena In mouse and Xenopus, Cfap206 was co-expressed with and dependent on Foxj1 CFAP206 protein localised to the basal body and to the axoneme of motile cilia. In Xenopus crispant larvae, the ciliary beat frequency of skin multiciliated cells was enhanced and bead transport across the epidermal mucociliary epithelium was reduced. Likewise, Cfap206 knockout mice revealed ciliary phenotypes. Electron tomography of immotile knockout mouse sperm flagella indicated a role in radial spoke formation reminiscent of FAP206 function in Tetrahymena Male infertility, hydrocephalus and impaired mucociliary clearance of the airways in the absence of laterality defects in Cfap206 mutant mice suggests that Cfap206 may represent a candidate for the subgroup of human primary ciliary dyskinesias caused by radial spoke defects.
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Affiliation(s)
- Anja Beckers
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Christian Adis
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Karin Schuster-Gossler
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Lena Tveriakhina
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Tim Ott
- Institute of Zoology, University of Hohenheim, Garbenstraße 30, 70593 Stuttgart, Germany
| | - Franziska Fuhl
- Institute of Zoology, University of Hohenheim, Garbenstraße 30, 70593 Stuttgart, Germany
| | - Jan Hegermann
- Institute of Functional and Applied Anatomy, OE8840, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Karsten Boldt
- Institute of Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Röntgenweg 11, 72076 Tübingen, Germany
| | - Katrin Serth
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Ev Rachev
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Leonie Alten
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Elisabeth Kremmer
- Institute of Molecular Immunology, Helmholtz Zentrum München, German Research Center for Environmental Health, Core Facility Monoclonal Antibodies, Marchioninistr. 25, 81377 München, Germany
| | - Marius Ueffing
- Institute of Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Röntgenweg 11, 72076 Tübingen, Germany
| | - Martin Blum
- Institute of Zoology, University of Hohenheim, Garbenstraße 30, 70593 Stuttgart, Germany
| | - Achim Gossler
- Institute for Molecular Biology, OE5250, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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11
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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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12
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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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13
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Clark S, Myers JB, King A, Fiala R, Novacek J, Pearce G, Heierhorst J, Reichow SL, Barbar EJ. Multivalency regulates activity in an intrinsically disordered transcription factor. eLife 2018; 7:36258. [PMID: 29714690 PMCID: PMC5963919 DOI: 10.7554/elife.36258] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/23/2018] [Indexed: 12/19/2022] Open
Abstract
The transcription factor ASCIZ (ATMIN, ZNF822) has an unusually high number of recognition motifs for the product of its main target gene, the hub protein LC8 (DYNLL1). Using a combination of biophysical methods, structural analysis by NMR and electron microscopy, and cellular transcription assays, we developed a model that proposes a concerted role of intrinsic disorder and multiple LC8 binding events in regulating LC8 transcription. We demonstrate that the long intrinsically disordered C-terminal domain of ASCIZ binds LC8 to form a dynamic ensemble of complexes with a gradient of transcriptional activity that is inversely proportional to LC8 occupancy. The preference for low occupancy complexes at saturating LC8 concentrations with both human and Drosophila ASCIZ indicates that negative cooperativity is an important feature of ASCIZ-LC8 interactions. The prevalence of intrinsic disorder and multivalency among transcription factors suggests that formation of heterogeneous, dynamic complexes is a widespread mechanism for tuning transcriptional regulation.
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Affiliation(s)
- Sarah Clark
- Department of Biochemistry and Biophysics, Oregon State University, Oregon, United States
| | - Janette B Myers
- Department of Chemistry, Portland State University, Oregon, United States
| | - Ashleigh King
- St. Vincent's Institute of Medical Research, The University of Melbourne, Victoria, Australia.,Department of Medicine, St. Vincent's Health, The University of Melbourne, Victoria, Australia
| | - Radovan Fiala
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Jiri Novacek
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Grant Pearce
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Jörg Heierhorst
- St. Vincent's Institute of Medical Research, The University of Melbourne, Victoria, Australia.,Department of Medicine, St. Vincent's Health, The University of Melbourne, Victoria, Australia
| | - Steve L Reichow
- Department of Chemistry, Portland State University, Oregon, United States
| | - Elisar J Barbar
- Department of Biochemistry and Biophysics, Oregon State University, Oregon, United States
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14
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Han X, Xie H, Wang Y, Zhao C. Radial spoke proteins regulate otolith formation during early zebrafish development. FASEB J 2018; 32:3984-3992. [PMID: 29475374 DOI: 10.1096/fj.201701359r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Radial spokes are structurally conserved, macromolecular complexes that are essential for the motility of 9 + 2 motile cilia. In Chlamydomonas species, mutations in radial spoke proteins result in ciliary motility defects. However, little is known about the function of radial spoke proteins during embryonic development. Here, we investigated the role of a novel radial spoke protein, leucine-rich repeat containing protein 23 (Lrrc23), during zebrafish embryonic development. Mutations in lrrc23 resulted in a selective otolith formation defect during early ear development. Similar otolith defects were also present in the radial spoke head 3 homolog ( rsph3) and radial spoke head 4 homolog A ( rsph4a) radial spoke mutants. Notably, the radial spoke protein mutations specifically affected ciliary motility in the otic vesicle (OV), whereas motile cilia in other organs functioned normally. Via high-speed video microscopy, we found that motile cilia formation was stochastic and transient in the OV. Importantly, all the motile cilia in the OV beat circularly, in contrast to the planar beating pattern of typical 9 + 2 motile cilia. We identified the key time frame for motile cilia formation during OV development. Finally, we showed that the functions of radial spoke proteins were conserved between zebrafish and Tetrahymena. Together, our results suggest that radial spoke proteins are essential for ciliary motility in the OV and that radial spoke-regulated OV motile cilia represent a unique type of cilia during early zebrafish embryonic development.-Han, X., Xie, H., Wang, Y., Zhao, C. Radial spoke proteins regulate otolith formation during early zebrafish development.
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Affiliation(s)
- Xiao Han
- Institute of Evolution and Marine Biodiversity, College of Marine Life Science, Ocean University of China, Qingdao, China
| | - Haibo Xie
- Institute of Evolution and Marine Biodiversity, College of Marine Life Science, Ocean University of China, Qingdao, China
| | - Yadong Wang
- Institute of Evolution and Marine Biodiversity, College of Marine Life Science, Ocean University of China, Qingdao, China
| | - Chengtian Zhao
- Institute of Evolution and Marine Biodiversity, College of Marine Life Science, Ocean University of China, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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15
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Bower R, Tritschler D, Mills KV, Heuser T, Nicastro D, Porter ME. DRC2/CCDC65 is a central hub for assembly of the nexin-dynein regulatory complex and other regulators of ciliary and flagellar motility. Mol Biol Cell 2017; 29:137-153. [PMID: 29167384 PMCID: PMC5909927 DOI: 10.1091/mbc.e17-08-0510] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 11/13/2017] [Accepted: 11/15/2017] [Indexed: 02/01/2023] Open
Abstract
DRC2 is a subunit of the nexin–dynein regulatory complex linked to primary ciliary dyskinesia. Little is known about the impact of drc2 mutations on axoneme composition and structure. We used proteomic and structural approaches to reveal that DRC2 coassembles with DRC1 to attach the N-DRC to the A-tubule and mediate interactions with other regulatory structures. The nexin–dynein regulatory complex (N-DRC) plays a central role in the regulation of ciliary and flagellar motility. In most species, the N-DRC contains at least 11 subunits, but the specific function of each subunit is unknown. Mutations in three subunits (DRC1, DRC2/CCDC65, DRC4/GAS8) have been linked to defects in ciliary motility in humans and lead to a ciliopathy known as primary ciliary dyskinesia (PCD). Here we characterize the biochemical, structural, and motility phenotypes of two mutations in the DRC2 gene of Chlamydomonas. Using high-resolution proteomic and structural approaches, we find that the C-terminal region of DRC2 is critical for the coassembly of DRC2 and DRC1 to form the base plate of N-DRC and its attachment to the outer doublet microtubule. Loss of DRC2 in drc2 mutants disrupts the assembly of several other N-DRC subunits and also destabilizes the assembly of several closely associated structures such as the inner dynein arms, the radial spokes, and the calmodulin- and spoke-associated complex. Our study provides new insights into the range of ciliary defects that can lead to PCD.
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Affiliation(s)
- Raqual Bower
- Department of Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Douglas Tritschler
- Department of Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Kristyn VanderWaal Mills
- Department of Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Thomas Heuser
- Biology Department and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454.,Vienna Biocenter Core Facilities, 1030 Vienna, Austria
| | - Daniela Nicastro
- Biology Department and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454.,Departments of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Mary E Porter
- Department of Genetics, Cell Biology, and Development, University of Minnesota Medical School, Minneapolis, MN 55455
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16
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Zhu X, Poghosyan E, Gopal R, Liu Y, Ciruelas KS, Maizy Y, Diener DR, King SM, Ishikawa T, Yang P. General and specific promotion of flagellar assembly by a flagellar nucleoside diphosphate kinase. Mol Biol Cell 2017; 28:3029-3042. [PMID: 28877983 PMCID: PMC5662260 DOI: 10.1091/mbc.e17-03-0156] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/25/2017] [Accepted: 08/30/2017] [Indexed: 12/20/2022] Open
Abstract
NDK5 promotes assembly of motile cilia and flagella with its structure and protein phosphorylation–related reactions instead of the canonical NDK activity. The novel mechanisms and dominant-negative effect of mutated functional NDK5 reveal the remarkable versatility of a molecular platform that is used in diverse cellular processes. Nucleoside diphosphate kinases (NDKs) play a central role in diverse cellular processes using the canonical NDK activity or alternative mechanisms that remain poorly defined. Our study of dimeric NDK5 in a flagellar motility control complex, the radial spoke (RS), has revealed new modalities. The flagella in Chlamydomonas ndk5 mutant were paralyzed, albeit only deficient in three RS subunits. RS morphology appeared severely changed in averaged cryo-electron tomograms, suggesting that NDK5 is crucial for the intact spokehead formation as well as RS structural stability. Intriguingly, ndk5’s flagella were also short, resembling those of an allelic spoke-less mutant. All ndk5’s phenotypes were rescued by expressions of NDK5 or a mutated NDK5 lacking the canonical kinase activity. Importantly, the mutated NDK5 that appeared fully functional in ndk5 cells elicited a dominant-negative effect in wild-type cells, causing paralyzed short flagella with hypophosphorylated, less abundant, but intact RSs, and accumulated hypophosphorylated NDK5 in the cell body. We propose that NDK5 dimer is an RS structural subunit with an additional mechanism that uses cross-talk between the two NDK monomers to accelerate phosphorylation-related assembly of RSs and entire flagella.
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Affiliation(s)
- Xiaoyan Zhu
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Emiliya Poghosyan
- Biomolecular Research Laboratory, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Radhika Gopal
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Yi Liu
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Kristine S Ciruelas
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Yousif Maizy
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
| | - Dennis R Diener
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520
| | - Stephen M King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
| | - Takashi Ishikawa
- Biomolecular Research Laboratory, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233
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17
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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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18
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Clark S, Nyarko A, Löhr F, Karplus PA, Barbar E. The Anchored Flexibility Model in LC8 Motif Recognition: Insights from the Chica Complex. Biochemistry 2015; 55:199-209. [PMID: 26652654 DOI: 10.1021/acs.biochem.5b01099] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
LC8 is a dimeric hub protein involved in a large number of interactions central to cell function. It binds short linear motifs--usually containing a Thr-Gln-Thr (TQT) triplet--in intrinsically disordered regions of its binding partners, some of which have several LC8 recognition motifs in tandem. Hallmarks of the 7-10 amino acid motif are a high variability of LC8 binding affinity and extensive sequence permutation outside the TQT triplet. To elucidate the molecular basis of motif recognition, we use a 69-residue segment of the human Chica spindle adaptor protein that contains four putative TQT recognition motifs in tandem. NMR-derived secondary chemical shifts and relaxation properties show that the Chica LC8 binding domain is essentially disordered with a dynamically restricted segment in one linker between motifs. Calorimetry of LC8 binding to synthetic motif-mimicking peptides shows that the first motif dominates LC8 recruitment. Crystal structures of the complexes of LC8 bound to each of two motif peptides show highly ordered and invariant TQT-LC8 interactions and more flexible and conformationally variable non-TQT-LC8 interactions. These data highlight rigidity in both LC8 residues that bind TQT and in the TQT portion of the motif as an important new characteristic of LC8 recognition. On the basis of these data and others in the literature, we propose that LC8 recognition is based on rigidly fixed interactions between LC8 and TQT residues that act as an anchor, coupled with inherently flexible interactions between LC8 and non-TQT residues. The "anchored flexibility" model explains the requirement for the TQT triplet and the ability of LC8 to accommodate a large variety of motif sequences and affinities.
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Affiliation(s)
- Sarah Clark
- Department of Biochemistry and Biophysics, Oregon State University , Corvallis, Oregon 97331, United States
| | - Afua Nyarko
- Department of Biochemistry and Biophysics, Oregon State University , Corvallis, Oregon 97331, United States
| | - Frank Löhr
- Institute of Biophysical Chemistry, Goethe-University , D-60438 Frankfurt, Germany
| | - P Andrew Karplus
- Department of Biochemistry and Biophysics, Oregon State University , Corvallis, Oregon 97331, United States
| | - Elisar Barbar
- Department of Biochemistry and Biophysics, Oregon State University , Corvallis, Oregon 97331, United States
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19
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Clark SA, Jespersen N, Woodward C, Barbar E. Multivalent IDP assemblies: Unique properties of LC8-associated, IDP duplex scaffolds. FEBS Lett 2015; 589:2543-51. [PMID: 26226419 DOI: 10.1016/j.febslet.2015.07.032] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 07/17/2015] [Accepted: 07/17/2015] [Indexed: 01/17/2023]
Abstract
A wide variety of subcellular complexes are composed of one or more intrinsically disordered proteins (IDPs) that are multivalent, flexible, and characterized by dynamic binding of diverse partner proteins. These multivalent IDP assemblies, of broad functional diversity, are classified here into five categories distinguished by the number of IDP chains and the arrangement of partner proteins in the functional complex. Examples of each category are summarized in the context of the exceptional molecular and biological properties of IDPs. One type - IDP duplex scaffolds - is considered in detail. Its unique features include parallel alignment of two IDP chains, formation of new self-associated domains, enhanced affinity for additional bivalent ligands, and ubiquitous binding of the hub protein LC8. For two IDP duplex scaffolds, dynein intermediate chain IC and nucleoporin Nup159, these duplex features, together with the inherent flexibility of IDPs, are central to their assembly and function. A new type of IDP-LC8 interaction, distributed binding of LC8 among multiple IDP recognition sites, is described for Nup159 assembly.
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Affiliation(s)
- Sarah A Clark
- Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR 97331, United States
| | - Nathan Jespersen
- Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR 97331, United States
| | - Clare Woodward
- Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, St. Paul, MN 55108, United States
| | - Elisar Barbar
- Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR 97331, United States.
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20
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Jeanson L, Copin B, Papon JF, Dastot-Le Moal F, Duquesnoy P, Montantin G, Cadranel J, Corvol H, Coste A, Désir J, Souayah A, Kott E, Collot N, Tissier S, Louis B, Tamalet A, de Blic J, Clement A, Escudier E, Amselem S, Legendre M. RSPH3 Mutations Cause Primary Ciliary Dyskinesia with Central-Complex Defects and a Near Absence of Radial Spokes. Am J Hum Genet 2015; 97:153-62. [PMID: 26073779 PMCID: PMC4571005 DOI: 10.1016/j.ajhg.2015.05.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/05/2015] [Indexed: 01/16/2023] Open
Abstract
Primary ciliary dyskinesia (PCD) is a rare autosomal-recessive condition resulting from structural and/or functional defects of the axoneme in motile cilia and sperm flagella. The great majority of mutations identified so far involve genes whose defects result in dynein-arm anomalies. By contrast, PCD due to CC/RS defects (those in the central complex [CC] and radial spokes [RSs]), which might be difficult to diagnose, remains mostly unexplained. We identified non-ambiguous RSPH3 mutations in 5 of 48 independent families affected by CC/RS defects. RSPH3, whose ortholog in the flagellated alga Chlamydomonas reinhardtii encodes a RS-stalk protein, is mainly expressed in respiratory and testicular cells. Its protein product, which localizes within the cilia of respiratory epithelial cells, was undetectable in airway cells from an individual with RSPH3 mutations and in whom RSPH23 (a RS-neck protein) and RSPH1 and RSPH4A (RS-head proteins) were found to be still present within cilia. In the case of RSPH3 mutations, high-speed-videomicroscopy analyses revealed the coexistence of immotile cilia and motile cilia with movements of reduced amplitude. A striking feature of the ultrastructural phenotype associated with RSPH3 mutations is the near absence of detectable RSs in all cilia in combination with a variable proportion of cilia with CC defects. Overall, this study shows that RSPH3 mutations contribute to disease in more than 10% of PCD-affected individuals with CC/RS defects, thereby allowing an accurate diagnosis to be made in such cases. It also unveils the key role of RSPH3 in the proper building of RSs and the CC in humans.
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Affiliation(s)
- Ludovic Jeanson
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France
| | - Bruno Copin
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Jean-François Papon
- INSERM UMR S955, Equipe 13, Université Paris-Est Créteil, Créteil 94000, France; Service d'Oto-Rhino-Laryngologie et de Chirurgie Cervico-Maxillo-Faciale, Hôpital Bicêtre, Assistance Publique - Hôpitaux de Paris, Le Kremlin-Bicêtre 94275, France
| | - Florence Dastot-Le Moal
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Philippe Duquesnoy
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France
| | - Guy Montantin
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Jacques Cadranel
- Service de Pneumologie-Centre Expert Maladies Pulmonaires Rares, Hôpital Tenon, Assistance Publique - Hôpitaux de Paris, Paris 75020, France; Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75020, France
| | - Harriet Corvol
- Service de Pneumologie Pédiatrique, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris and Centre National de Référence des Maladies Respiratoires Rares, Paris 75012, France; INSERM UMR S938, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France
| | - André Coste
- INSERM UMR S955, Equipe 13, Université Paris-Est Créteil, Créteil 94000, France; Service d'Oto-Rhino-Laryngologie et de Chirurgie Cervico-Faciale, Hôpital Intercommunal et Groupe Hospitalier Henri Mondor-Albert Chenevier, Assistance Publique - Hôpitaux de Paris, Créteil 94000, France
| | - Julie Désir
- Département de Génétique Médicale, Université Libre de Bruxelles and Hôpital Erasme, Brussels 1020, Belgium
| | - Anissa Souayah
- Service d'Oto-Rhino-Laryngologie, Hôpital Universitaire des Enfants Reine Fabiola, Brussels 1020, Belgium
| | - Esther Kott
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France
| | - Nathalie Collot
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Sylvie Tissier
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Bruno Louis
- INSERM UMR S955, Equipe 13, Université Paris-Est Créteil, Créteil 94000, France
| | - Aline Tamalet
- Service de Pneumologie Pédiatrique, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris and Centre National de Référence des Maladies Respiratoires Rares, Paris 75012, France
| | - Jacques de Blic
- Service de Pneumologie et Allergologie Pédiatriques, Groupe Hospitalier Necker-Enfants Malades, Assistance Publique - Hôpitaux de Paris and Université Paris Descartes, Paris 75015, France
| | - Annick Clement
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France; Service de Pneumologie Pédiatrique, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris and Centre National de Référence des Maladies Respiratoires Rares, Paris 75012, France
| | - Estelle Escudier
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France; Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
| | - Serge Amselem
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France; Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France.
| | - Marie Legendre
- INSERM UMR S933, Université Pierre et Marie Curie (Paris 6), Sorbonne Universités, Paris 75012, France; Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Assistance Publique - Hôpitaux de Paris, Paris 75012, France
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21
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Desai PB, Freshour JR, Mitchell DR. Chlamydomonas axonemal dynein assembly locus ODA8 encodes a conserved flagellar protein needed for cytoplasmic maturation of outer dynein arm complexes. Cytoskeleton (Hoboken) 2015; 72:16-28. [PMID: 25558044 PMCID: PMC4361367 DOI: 10.1002/cm.21206] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/12/2014] [Accepted: 12/19/2014] [Indexed: 12/13/2022]
Abstract
The Chlamydomonas reinhardtii oda8 mutation blocks assembly of flagellar outer dynein arms (ODAs), and interacts genetically with ODA5 and ODA10, which encode axonemal proteins thought to aid dynein binding onto axonemal docking sites. We positionally cloned ODA8 and identified the gene product as the algal homolog of vertebrate LRRC56. Its flagellar localization depends on ODA5 and ODA10, consistent with genetic interaction studies, but phylogenomics suggests that LRRC56 homologs play a role in intraflagellar transport (IFT)-dependent assembly of outer row dynein arms, not axonemal docking. ODA8 distribution between cytoplasm and flagella is similar to that of IFT proteins and about half of flagellar ODA8 is in the soluble matrix fraction. Dynein extracted in vitro from wild type axonemes will rebind efficiently to oda8 mutant axonemes, without re-binding of ODA8, further supporting a role in dynein assembly or transport, not axonemal binding. Assays comparing preassembled ODA complexes from the cytoplasm of wild type and mutant strains show that dynein in oda8 mutant cytoplasm has not properly preassembled and cannot bind normally onto oda axonemes. We conclude that ODA8 plays an important role in formation and transport of mature dynein complexes during flagellar assembly. © 2014 The Authors. Cytoskeleton Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Paurav B Desai
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, Syracuse, New York
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22
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Vasudevan KK, Song K, Alford LM, Sale WS, Dymek EE, Smith EF, Hennessey T, Joachimiak E, Urbanska P, Wloga D, Dentler W, Nicastro D, Gaertig J. FAP206 is a microtubule-docking adapter for ciliary radial spoke 2 and dynein c. Mol Biol Cell 2014; 26:696-710. [PMID: 25540426 PMCID: PMC4325840 DOI: 10.1091/mbc.e14-11-1506] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Radial spokes are conserved macromolecular complexes that are essential for ciliary motility. Little is known about the assembly and functions of the three individual radial spokes, RS1, RS2, and RS3. In Tetrahymena, a conserved ciliary protein, FAP206, docks RS2 and dynein c to the doublet microtubule. Radial spokes are conserved macromolecular complexes that are essential for ciliary motility. A triplet of three radial spokes, RS1, RS2, and RS3, repeats every 96 nm along the doublet microtubules. Each spoke has a distinct base that docks to the doublet and is linked to different inner dynein arms. Little is known about the assembly and functions of individual radial spokes. A knockout of the conserved ciliary protein FAP206 in the ciliate Tetrahymena resulted in slow cell motility. Cryo–electron tomography showed that in the absence of FAP206, the 96-nm repeats lacked RS2 and dynein c. Occasionally, RS2 assembled but lacked both the front prong of its microtubule base and dynein c, whose tail is attached to the front prong. Overexpressed GFP-FAP206 decorated nonciliary microtubules in vivo. Thus FAP206 is likely part of the front prong and docks RS2 and dynein c to the microtubule.
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Affiliation(s)
| | - Kangkang Song
- Department of Biology, Rosenstiel Center, Brandeis University, Waltham, MA 02454
| | - Lea M Alford
- Department of Cell Biology, Emory University, Atlanta, GA 30303
| | - Winfield S Sale
- Department of Cell Biology, Emory University, Atlanta, GA 30303
| | - Erin E Dymek
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755
| | - Elizabeth F Smith
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755
| | - Todd Hennessey
- Department of Biological Sciences, State University of New York, Buffalo, NY 14260
| | - Ewa Joachimiak
- Department of Cell Biology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland Department of Animal Physiology, Faculty of Biology, University of Warsaw, 02-096 Warsaw, Poland
| | - Paulina Urbanska
- Department of Cell Biology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
| | - Dorota Wloga
- Department of Cell Biology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
| | - William Dentler
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045
| | - Daniela Nicastro
- Department of Biology, Rosenstiel Center, Brandeis University, Waltham, MA 02454
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
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23
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Viswanadha R, Hunter EL, Yamamoto R, Wirschell M, Alford LM, Dutcher SK, Sale WS. The ciliary inner dynein arm, I1 dynein, is assembled in the cytoplasm and transported by IFT before axonemal docking. Cytoskeleton (Hoboken) 2014; 71:573-86. [PMID: 25252184 DOI: 10.1002/cm.21192] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/11/2014] [Accepted: 09/15/2014] [Indexed: 01/11/2023]
Abstract
To determine mechanisms of assembly of ciliary dyneins, we focused on the Chlamydomonas inner dynein arm, I1 dynein, also known as dynein f. I1 dynein assembles in the cytoplasm as a 20S complex similar to the 20S I1 dynein complex isolated from the axoneme. The intermediate chain subunit, IC140 (IDA7), and heavy chains (IDA1, IDA2) are required for 20S I1 dynein preassembly in the cytoplasm. Unlike I1 dynein derived from the axoneme, the cytoplasmic 20S I1 complex will not rebind I1-deficient axonemes in vitro. To test the hypothesis that I1 dynein is transported to the distal tip of the cilia for assembly in the axoneme, we performed cytoplasmic complementation in dikaryons formed between wild-type and I1 dynein mutant cells. Rescue of I1 dynein assembly in mutant cilia occurred first at the distal tip and then proceeded toward the proximal axoneme. Notably, in contrast to other combinations, I1 dynein assembly was significantly delayed in dikaryons formed between ida7 and ida3. Furthermore, rescue of I1 dynein assembly required new protein synthesis in the ida7 × ida3 dikaryons. On the basis of the additional observations, we postulate that IDA3 is required for 20S I1 dynein transport. Cytoplasmic complementation in dikaryons using the conditional kinesin-2 mutant, fla10-1 revealed that transport of I1 dynein is dependent on kinesin-2 activity. Thus, I1 dynein complex assembly depends upon IFT for transport to the ciliary distal tip prior to docking in the axoneme.
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Affiliation(s)
- Rasagnya Viswanadha
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
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24
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Barbar E, Nyarko A. Polybivalency and disordered proteins in ordering macromolecular assemblies. Semin Cell Dev Biol 2014; 37:20-5. [PMID: 25263009 DOI: 10.1016/j.semcdb.2014.09.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/10/2014] [Accepted: 09/13/2014] [Indexed: 12/20/2022]
Abstract
Intrinsically disordered proteins (IDPs) are prevalent in macromolecular assemblies and are thought to mediate protein recognition in complex regulatory processes and signaling pathways. The formation of a polybivalent scaffold is a key process by which IDPs drive early steps in macromolecular assemblies. Three intrinsically disordered proteins, IC, Swallow and Nup159, are core components, respectively, of cytoplasmic dynein, bicoid mRNA localization apparatus, and nuclear pore complexes. In all three systems, the hub protein LC8 recognizes on the IDP, short linear motifs that are fully disordered in the apo form, but adopt a β-strand when bound to LC8. The IDP/LC8 complex forms a bivalent scaffold primed to bind additional bivalent ligands. Scaffold formation also promotes self-association and/or higher order organization of the IDP components at a site distant from LC8 binding. Rigorous thermodynamic analyses imply that association of additional bivalent ligands is driven by entropic effects where the first binding event is weak but subsequent binding of additional ligands occurs with higher affinity. Here, we review specific examples of macromolecular assemblies in which polybivalency of aligned IDP duplexes not only enhances binding affinity and results in formation of a stable complex but also compensates unfavorable steric and enthalpic interactions. We propose that polybivalent scaffold assembly involving IDPs and LC8-like proteins is a general process in the cell biology of a class of multi-protein structures that are stable yet fine-tuned for diverse cellular requirements.
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Affiliation(s)
- Elisar Barbar
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, United States.
| | - Afua Nyarko
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, United States
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25
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Alford LM, Mattheyses AL, Hunter EL, Lin H, Dutcher SK, Sale WS. The Chlamydomonas mutant pf27 reveals novel features of ciliary radial spoke assembly. Cytoskeleton (Hoboken) 2014; 70:804-18. [PMID: 24124175 DOI: 10.1002/cm.21144] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 01/05/2023]
Abstract
To address the mechanisms of ciliary radial spoke assembly, we took advantage of the Chlamydomonas pf27 mutant. The radial spokes that assemble in pf27 are localized to the proximal quarter of the axoneme, but otherwise are fully assembled into 20S radial spoke complexes competent to bind spokeless axonemes in vitro. Thus, pf27 is not defective in radial spoke assembly or docking to the axoneme. Rather, our results suggest that pf27 is defective in the transport of spoke complexes. During ciliary regeneration in pf27, radial spoke assembly occurs asynchronously from other axonemal components. In contrast, during ciliary regeneration in wild-type Chlamydomonas, radial spokes and other axonemal components assemble concurrently as the axoneme grows. Complementation in temporary dikaryons between wild-type and pf27 reveals rescue of radial spoke assembly that begins at the distal tip, allowing further assembly to proceed from tip to base of the axoneme. Notably, rescued assembly of radial spokes occurred independently of the established proximal radial spokes in pf27 axonemes in dikaryons. These results reveal that 20S radial spokes can assemble proximally in the pf27 cilium but as the cilium lengthens, spoke assembly requires transport. We postulate that PF27 encodes an adaptor or modifier protein required for radial spoke–IFT interaction.
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26
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Bower R, Tritschler D, Vanderwaal K, Perrone CA, Mueller J, Fox L, Sale WS, Porter ME. The N-DRC forms a conserved biochemical complex that maintains outer doublet alignment and limits microtubule sliding in motile axonemes. Mol Biol Cell 2013; 24:1134-52. [PMID: 23427265 PMCID: PMC3623635 DOI: 10.1091/mbc.e12-11-0801] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The nexin–dynein regulatory complex (N-DRC) is implicated in the control of dynein activity as a structural component of the nexin link. This study identifies several new subunits of the N-DRC and demonstrates for the first time that it forms a discrete biochemical complex that maintains outer doublet integrity and regulates microtubule sliding. The nexin–dynein regulatory complex (N-DRC) is proposed to coordinate dynein arm activity and interconnect doublet microtubules. Here we identify a conserved region in DRC4 critical for assembly of the N-DRC into the axoneme. At least 10 subunits associate with DRC4 to form a discrete complex distinct from other axonemal substructures. Transformation of drc4 mutants with epitope-tagged DRC4 rescues the motility defects and restores assembly of missing DRC subunits and associated inner-arm dyneins. Four new DRC subunits contain calcium-signaling motifs and/or AAA domains and are nearly ubiquitous in species with motile cilia. However, drc mutants are motile and maintain the 9 + 2 organization of the axoneme. To evaluate the function of the N-DRC, we analyzed ATP-induced reactivation of isolated axonemes. Rather than the reactivated bending observed with wild-type axonemes, ATP addition to drc-mutant axonemes resulted in splaying of doublets in the distal region, followed by oscillatory bending between pairs of doublets. Thus the N-DRC provides some but not all of the resistance to microtubule sliding and helps to maintain optimal alignment of doublets for productive flagellar motility. These findings provide new insights into the mechanisms that regulate motility and further highlight the importance of the proximal region of the axoneme in generating flagellar bending.
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Affiliation(s)
- Raqual Bower
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
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27
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Sivadas P, Dienes JM, St Maurice M, Meek WD, Yang P. A flagellar A-kinase anchoring protein with two amphipathic helices forms a structural scaffold in the radial spoke complex. ACTA ACUST UNITED AC 2013; 199:639-51. [PMID: 23148234 PMCID: PMC3494852 DOI: 10.1083/jcb.201111042] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Amphipathic helices in the A-kinase anchoring protein RSP3 bind to spoke proteins involved in the assembly and modulation of the flagellar radial spoke complex, expanding the repertoire of these versatile helical protein motifs. A-kinase anchoring proteins (AKAPs) contain an amphipathic helix (AH) that binds the dimerization and docking (D/D) domain, RIIa, in cAMP-dependent protein kinase A (PKA). Many AKAPs were discovered solely based on the AH–RIIa interaction in vitro. An RIIa or a similar Dpy-30 domain is also present in numerous diverged molecules that are implicated in critical processes as diverse as flagellar beating, membrane trafficking, histone methylation, and stem cell differentiation, yet these molecules remain poorly characterized. Here we demonstrate that an AKAP, RSP3, forms a dimeric structural scaffold in the flagellar radial spoke complex, anchoring through two distinct AHs, the RIIa and Dpy-30 domains, in four non-PKA spoke proteins involved in the assembly and modulation of the complex. Interestingly, one AH can bind both RIIa and Dpy-30 domains in vitro. Thus, AHs and D/D domains constitute a versatile yet potentially promiscuous system for localizing various effector mechanisms. These results greatly expand the current concept about anchoring mechanisms and AKAPs.
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Affiliation(s)
- Priyanka Sivadas
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53201, USA
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28
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Nyarko A, Song Y, Nováček J, Žídek L, Barbar E. Multiple recognition motifs in nucleoporin Nup159 provide a stable and rigid Nup159-Dyn2 assembly. J Biol Chem 2012; 288:2614-22. [PMID: 23223634 DOI: 10.1074/jbc.m112.432831] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dyn2 is the yeast ortholog of the molecular hub LC8, which binds disordered proteins and promotes their self-association and higher order assembly. Dyn2 is proposed to dimerize and stabilize the Nup82-Nsp1-Nup159 complex of the nuclear pore assembly through its interaction with nucleoporin Nup159. Nup159 has six LC8 recognition motifs separated by short linkers. NMR experiments reported here show that the Dyn2 binding domain of Nup159 is intrinsically disordered and that binding of one equivalent of Dyn2 dimer aligns two Nup159 chains along the full Dyn2 binding domain to form a bivalent scaffold that promotes binding of other Dyn2 dimers. Isothermal titration calorimetry of Dyn2 binding to Nup constructs of increasing lengths determine that the third LC8 recognition motifs does not bind Dyn2. A new approach to identifying active LC8 recognition motifs based on NMR-detected β-sheet propensities is presented. Isothermal titration calorimetry experiments also show that, due to unfavorable entropy changes, a Nup-Dyn2 complex with three Dyn2 dimers is more stable than the wild-type complex with five Dyn2 dimers. The calorimetric results argue that, from a thermodynamics perspective, only three Dyn2 dimers are needed for optimal stability and suggest that the evolutionary adaptation of multiple tandem LC8 recognition motifs imparts to the complex other properties such as rigidity and a kink in the rod-like structure. These findings extend the repertoire of functions of intrinsically disordered protein to fine-tuning and versatile assembly of higher order macromolecular complexes.
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Affiliation(s)
- Afua Nyarko
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon 97331, USA
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