Magnetic Actuation Methods in Bio/Soft Robotics

Advanced Functional Materials, Год журнала: 2020, Номер 31(11)

Опубликована: Дек. 23, 2020

Abstract In recent years, magnetism has gained an enormous amount of interest among researchers for actuating different sizes and types bio/soft robots, which can be via electromagnetic‐coil system, or a system moving permanent magnets. Different actuation strategies are used in robots with magnetic having number advantages possible realization microscale such as bioinspired microrobots, tetherless cellular even normal size soft electromagnetic medical robots. This review provides summary research magnetically actuated discussing fabrication processes methods together relevant applications biomedical area discusses future prospects this way improvements performance

Язык: Английский

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In situ cryo-electron tomography reveals the asymmetric architecture of mammalian sperm axonemes

Nature Structural & Molecular Biology, Год журнала: 2023, Номер 30(3), С. 360 - 369

Опубликована: Янв. 2, 2023

The flagella of mammalian sperm display non-planar, asymmetric beating, in contrast to the planar, symmetric beating from sea urchin and unicellular organisms. molecular basis this difference is unclear. Here, we perform situ cryo-electron tomography mouse human sperm, providing highest-resolution structural information date. Our subtomogram averages reveal sperm-specific protein complexes within microtubules, radial spokes nexin-dynein regulatory complexes. locations structures these suggest potential roles enhancing mechanical strength axonemes regulating dynein-based axonemal bending. Intriguingly, find that each nine outer microtubule doublets decorated with a distinct combination We propose distribution proteins differentially regulates sliding doublet may underlie sperm.

Язык: Английский

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The multi‐scale architecture of mammalian sperm flagella and implications for ciliary motility

The EMBO Journal, Год журнала: 2021, Номер 40(7)

Опубликована: Март 10, 2021

Article10 March 2021Open Access Transparent process The multi-scale architecture of mammalian sperm flagella and implications for ciliary motility Miguel Ricardo Leung orcid.org/0000-0002-3348-1096 Cryo-Electron Microscopy, Bijvoet Center Biomolecular Research, Utrecht University, Utrecht, Netherlands Division Structural Biology, Wellcome Centre Human Genetics, University Oxford, UK Search more papers by this author Marc C Roelofs orcid.org/0000-0002-2342-3474 Ravi Teja orcid.org/0000-0002-0360-4307 Paula Maitan orcid.org/0000-0001-6677-9609 Department Equine Sciences, Faculty Veterinary Medicine, Department, Universidade Federal de Viçosa, Brazil Heiko Henning orcid.org/0000-0003-4064-7792 Min Zhang Farm & Animal Health Elizabeth G Bromfield orcid.org/0000-0001-7256-1403 Priority Research Reproductive Science, Newcastle, Callaghan, NSW, Australia Stuart Howes orcid.org/0000-0001-6129-1882 Bart M Gadella Hermes Bloomfield-Gadêlha orcid.org/0000-0001-8053-9249 Engineering Mathematics, Bristol, Tzviya Zeev-Ben-Mordehai Corresponding Author [email protected] orcid.org/0000-0002-2571-550X Information Leung1,2, Roelofs1, Ravi1, Maitan3,4, Henning3, Zhang5, Bromfield5,6, Howes1, Gadella5, Bloomfield-Gadêlha7 *,1,2 1Cryo-Electron 2The 3Department 4Veterinary 5Department 6Priority 7Department *Corresponding author. Tel: +31 30 253 3178; E-mail: EMBO Journal (2021)40:e107410https://doi.org/10.15252/embj.2020107410 PDFDownload PDF article text main figures. Peer ReviewDownload a summary the editorial decision including letters, reviewer comments responses to feedback. ToolsAdd favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures Info Abstract Motile cilia are molecular machines used myriad eukaryotic cells swim through fluid environments. However, available structures represent only handful cell types, limiting our understanding how modified support in diverse media. Here, we use cryo-focused ion beam milling-enabled cryo-electron tomography image from three species. We resolve in-cell centrioles, axonemal doublets, central pair apparatus, endpiece singlets, revealing novel protofilament-bridging microtubule inner proteins throughout flagellum. present native flagellar base, which is crucial shaping beat. show that outer dense fibers directly coupled doublets principal piece but not midpiece. Thus, ornamented across scales, protofilament-bracing reinforcing microtubules at nano-scale accessory impose micron-scale asymmetries on entire assembly. Our provide vital foundations linking structure evolution. SYNOPSIS Diverse organisms types rely evolutionarily ancient structurally conserved motile broad range situ uncovers structural specialisations several Mammalian reinforced proteins. connecting base flagellum forms an intricate, asymmetric chamber around centrioles. atypical distal centriole composed doublet splayed out two singlet microtubules. Outer piece, Introduction Cilia, also called flagella, organelles propel themselves environments or move their surfaces (Mitchell, 2017; Wan, 2018). These intricate paragons self-organization built extensive array active passive elements that, together, able spontaneously generate oscillatory wave-like motion (Gaffney et al, 2011). basic swaths tree, providing information minimal needed spontaneous undulation (Brokaw, 2009). because they operate wide environments, different waveforms (Khan Scholey, 2018) modulated viscosity (Smith cilium continuous assembly compound (Ishikawa, 2017). basal body, typically cylinder triplet transitions into axoneme, consists nine arrayed Axonemal anchor hundreds dynein motors power regulate movement. Axoneme has been studied extensively (cryo-ET) Chlamydomonas, Tetrahymena, sea urchin (Nicastro 2006, 2011; Pigino 2012; Owa 2019). Recent studies have begun shed light species- type-specific specializations (Lin 2014a; Yamaguchi 2018; Imhof 2019; Greenan 2020), motivating efforts expand pantheon axoneme research. Perhaps most striking example diversity species sperm, highly specialized defined function—to find fuse with egg. Sperm consist head, contains genetic payload, tail, cilium. Despite streamlined structure, simultaneously type (Gage, Lüpold Pitnick, 2018), reflecting sheer reproductive modes fertilization arenas, watery media marine invertebrates freshwater viscous fluids female tract mammals. Because function, natural variation form presents unique opportunity understand diversification cilia. characterized surround dwarf (Fawcett, 1975), unlike whose tails essentially 1970). In associated filamentous cytoskeletal (ODFs) lengths. ODFs further surrounded sheath mitochondria midpiece reticular fibrous piece. proposed stabilize beating long (Lindemann, 1996; Lindemann Lesich, 2016). facilitate movement suppressing buckling instabilities would otherwise cause circles (Gadêlha Gaffney, Indeed, many cases male infertility linked defects these (Serres 1986; Haidl 1991; Zhao still do fully modulate beat since there very little interact proper. Another distinguishing feature anchored body (Avidor-Reiss, Instead, large scaffold isolated bovine was cryo-ET, complex (Ounjai 2012). purification resulted loss paucity intact it varies often head shapes. centrioles located neck, where nucleus attaches closer referred as proximal (PC) one (DC). During spermiogenesis mammals, DC remodeled point no longer resembles canonical centriole. This thought degeneration (Manandhar 2000), recent work showed fact functional participates orchestrating first zygotic division (Fishman Such drastic deviations investigated detail. combine (cryo-FIB) cryo-ET (Marko 2007; Rigort 2012) subtomogram averaging mature species—the pig (Sus scrofa), horse (Equus caballus), mouse (Mus musculus)—that differ terms gross morphology, motility, metabolism (Fig 1A–C). leverage uniquely capabilities define microtubule-based assemblies critical interactions structures. take advantage shape order relationships change Figure 1. A–C. Low-magnification cryo-EM projection images (A), (B), (C) sperm. Different regions discussed paper annotated follows: green—neck, yellow—midpiece, coral—principal pink—endpiece. D–F. Tomographic slices cryo-FIB-milled lamellae (D), (E), (F) Transverse (D'–F') complete triplets (D') (E'), (F'). Complete indicated green arrowheads black outlines, while degenerated white outlines. Note electron-dense material lumen (asterisks D D'). G. region PC tubulin backbone gray protein densities colored individually. A-tubule MIPs colored: MIP1—green, MIP2—yellow, MIP3—orange, MIP4—red, MIP5—purple, MIP6—blue. B-tubule MIP7—magenta. C-tubule MIP8—light pink, MIP9—pink. A-C linker gold putative A-link olive green. H. Reconstruction generated plotting average back original particle positions orientations tomogram. plotback four part captured lamella. A–C Data information: Labels: nuc—nucleus, bp—baseplate. Scale bars: (A–C) 20 µm; (D–F) 250 nm; 100 nm. Download figure PowerPoint large, additionally decorated densities. scales—from increase effective size rigidity likely reinforce themselves. discuss motility. Results neck containing too thick (~600–700 nm) direct imaging so subcellular milieu, cryo-FIB milling thin suitable high-resolution 1). Cryo-ET confirmed indeed 1D–F). Unexpectedly, found all same length (Figs 1, EV1). Shorter grouped side centriole, giving dorsoventral asymmetry EV1A). Consistent previous reports degenerates rodents (Woolley Fawcett, 1973; Manandhar 1998), prominent unequivocally some centriolar remain 1F), demonstrating incomplete. observed well various stages degeneration, had degraded 1F'). Click here figure. EV1. features unequal lengths (top panel), shorter side, (bottom panel). Many (MIPs) other Details MIP PC. determined 1G). parts were lamellae, includes particles ~400 nm While overall similar (Li Guichard 2013; 2018, 2020; Le Guennec differs (MIPs; Fig EV1B). MIPs, six A-tubule, B-tubule, 1G EV1C). unique, MIP2 (yellow) binds protofilament A12, MIP3 (orange) bridging protofilaments A13 A1, MIP4 (red) A2, MIP5 (purple) A5, MIP6 (blue) A6 A7. MIP1 (green), A9, reported CHO (Greenan Trichonympha (Guichard 2013), Paramecium (Le bodies respiratory epithelia 2020). seam between A9 A10 (Ichikawa Ma 2019), suggests seam-stabilizing seam-recognizing structure. helical MIP7 (magenta) B3-9. groups C-tubule, MIP8 (light pink) C2-C4 MIP9 (pink) C5–C7. junctions A- B-tubules (cyan) B- C-tubules (turquoise) non-tubulin repeat every 8 staggered relative each when viewed luminal resolved density (gold), C9 C10, possibly (olive green), A8/A9 H). transition zone Unlike structures, observe bridge B1-B2 C1-C2 It difficult tell whether differences patterns due As any may be Nonetheless, clear great core accessorized, raises questions about functions MIPs. next organization tracing Volta phase plate (VPP; Danev 2014) cryo-tomograms whole 2). microtubules, singlets extending 2A–F). 2A–D), extend almost far proximally pair. departure open arranged asymmetrically singlets. spaced inconsistently, suggesting lack projections characteristic apparatus (CPA). Mouse beyond 2E F). 2. (DC) A–F. Microtubules (A, B), (C, D), (E, F) traced Doublets blue (A-tubule blue, dark blue), pink. G–I. DC-to-axoneme geometry (G, arrows dashed lines) coincides appearance (H, arrows) (I, compare insets boxes). (I), indicate cross-sections boxes taken from. J. turquoise consistent scaffold. represents closest (the area shown (G–I)). RSs—radial spokes, cpa—central At—A-tubule, Bt—B-tubule. To precisely transition, imaged 2G–J). such radial spokes CPA 2H). onset 2G), splayed-open DC. 2I), binding related regulated then averaging, presence distinct those 2J). (gold turquoise), correspond waveform depends greatly properties (Riedel-Kruse Hilfinger, 2007), organized dimensions type. capture full three-dimensional complexity took enhanced contrast provided VPP, allowed us trace retaining context surrounding 3A–C, Movies EV1–EV3). Semi-automated neural network-based segmentation (Chen 2017) revealed enclosing Although precise shapes 3D–F), its general appears 3. Slices Proximal green, blue) bars yellow. flanking C, Three-dimensional gray, segmented semi-automatically network, manually. bp—baseplate, sc—striated columns, odf—outer fibers, mito—mitochondria. striated columns (SCs), banded appearance. Following numbering scheme laid 2012), SCs follow pattern grouping splitting. can grossly divided left right regions. vault 8, 9, 2, 3 merge, whereas comprises 4, 5, 6, 7 3D–F, panels iv). gradually separate, eventually splitting separate distally v). displays both marked left–right embedded within always side. formed Y-shaped SC gives 3D, panel ii). extends interstices 1D–F) 1D Intriguingly, facing column 9 3D). 3A D, yellow goldenrod), resemble conspicuously absent 3C F), arrangement reminiscent distribution centrosomal speriolin (Goto 2010; Ito anchors species-specific gain insight 4) 96-nm 5). system, thus filling gaps gallery network examined EV2)

Язык: Английский

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The sperm centrioles

Molecular and Cellular Endocrinology, Год журнала: 2020, Номер 518, С. 110987 - 110987

Опубликована: Авг. 15, 2020

Язык: Английский

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A dynamic basal complex modulates mammalian sperm movement

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июнь 21, 2021

Abstract Reproductive success depends on efficient sperm movement driven by axonemal dynein-mediated microtubule sliding. Models predict sliding at the base of tail – centriole but such has never been observed. Centrioles are ancient organelles with a conserved architecture; their rigidity is thought to restrict Here, we show that, in mammalian sperm, atypical distal (DC) and its surrounding pericentriolar matrix form dynamic basal complex (DBC) that facilitates cascade internal deformations, coupling beating asymmetric head kinking. During beating, DC’s right side surroundings slide ~300 nm rostrally relative left side. The deformation throughout DBC transmitted head-tail junction; thus, tilts left, generating kinking motion. These findings suggest evolved as linker into single self-coordinated system.

Язык: Английский

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De novo protein identification in mammalian sperm using in situ cryoelectron tomography and AlphaFold2 docking

Cell, Год журнала: 2023, Номер 186(23), С. 5041 - 5053.e19

Опубликована: Окт. 20, 2023

To understand the molecular mechanisms of cellular pathways, contemporary workflows typically require multiple techniques to identify proteins, track their localization, and determine structures in vitro. Here, we combined cryoelectron tomography (cryo-ET) AlphaFold2 modeling address these questions how mammalian sperm are built situ. Our cryo-ET subtomogram averaging provided 6.0-Å reconstructions axonemal microtubule structures. The well-resolved tertiary allowed us unbiasedly match sperm-specific densities with 21,615 AlphaFold2-predicted protein models mouse proteome. We identified Tektin 5, CCDC105, SPACA9 as novel microtubule-associated proteins. These proteins form an extensive interaction network crosslinking lumen doublet microtubules, suggesting roles modulating mechanical properties filaments. Indeed, Tekt5 −/− possess more deformed flagella 180° bends. Together, our studies presented a visual proteomics workflow shed light on vivo functions 5.

Язык: Английский

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CiliaQ: a simple, open-source software for automated quantification of ciliary morphology and fluorescence in 2D, 3D, and 4D images

The European Physical Journal E, Год журнала: 2021, Номер 44(2)

Опубликована: Фев. 1, 2021

Abstract Cilia are hair-like membrane protrusions that emanate from the surface of most vertebrate cells and classified into motile primary cilia. Motile cilia move fluid flow or propel cells, while also fulfill sensory functions. Primary immotile act as a cellular antenna, translating environmental cues responses. Ciliary dysfunction leads to severe diseases, commonly termed ciliopathies. The molecular details underlying ciliopathies ciliary function are, however, not well understood. Since small subcellular compartments, imaging-based approaches have been used study them. However, tools comprehensively analyze images lacking. Automatic analysis require commercial software limited 2D only few parameters. widely manual time consuming, user-biased, difficult compare. Here, we present CiliaQ, package open-source, freely available, easy-to-use ImageJ plugins. CiliaQ allows high-throughput 3D, static time-lapse fluorescence microscopy in cell culture tissues, outputs comprehensive list parameters for morphology, length, bending, orientation, intensity, making it broadly applicable. We envision resource platform reproducible health disease. Graphic abstract

Язык: Английский

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Control of Helical Navigation by Three-Dimensional Flagellar Beating

Physical Review Letters, Год журнала: 2021, Номер 126(8)

Опубликована: Фев. 24, 2021

Helical swimming is a ubiquitous strategy for motile cells to generate self-gradients environmental sensing. The model biflagellate Chlamydomonas reinhardtii rotates at constant 1–2 Hz as it swims, but the mechanism unclear. Here, we show unequivocally that rolling motion derives from persistent, nonplanar flagellar beat pattern. This revealed by high-speed imaging and micromanipulation of live cells. We construct fully 3D relate beating directly free-swimming trajectories. For realistic geometries, reproduces both sense magnitude axial rotation helical requires further symmetry breaking between two flagella. These functional differences underlie all tactic responses, particularly phototaxis. propose control which steer toward or away light modulating sign biflagellar dominance.Received 27 September 2020Revised 10 December 2020Accepted 13 January 2021DOI:https://doi.org/10.1103/PhysRevLett.126.088003Published American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution this work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasBiological fluid dynamicsCell locomotionSwimmingPhysical SystemsCiliaMicroswimmersBiological PhysicsFluid Dynamics

Язык: Английский

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Advances in sperm analysis: techniques, discoveries and applications

Nature Reviews Urology, Год журнала: 2021, Номер 18(8), С. 447 - 467

Опубликована: Июнь 1, 2021

Язык: Английский

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Morphological and Molecular Bases of Male Infertility: A Closer Look at Sperm Flagellum

Genes, Год журнала: 2023, Номер 14(2), С. 383 - 383

Опубликована: Фев. 1, 2023

Infertility is a major health problem worldwide without an effective therapy or cure. It estimated to affect 8–12% of couples in the reproductive age group, equally affecting both genders. There no single cause infertility, and its knowledge still far from complete, with about 30% infertile having identified (named idiopathic infertility). Among male causes asthenozoospermia (i.e., reduced sperm motility) one most observed, being that more than 20% men have this condition. In recent years, many researchers focused on possible factors leading asthenozoospermia, revealing existence cellular molecular players. So far, 4000 genes are thought be involved production as regulators different aspects development, maturation, function, all can potentially infertility if mutated. review, we aim give brief overview typical flagellum morphology compile some relevant information regarding genetic focus immotility related structure, function.

Язык: Английский

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