1
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Niazi A, Kim JA, Kim DK, Lu D, Sterin I, Park J, Park S. Microvilli control the morphogenesis of the tectorial membrane extracellular matrix. Dev Cell 2024:S1534-5807(24)00693-2. [PMID: 39657673 DOI: 10.1016/j.devcel.2024.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 09/17/2024] [Accepted: 11/13/2024] [Indexed: 12/12/2024]
Abstract
The apical extracellular matrix (aECM), organized by polarized epithelial cells, exhibits complex structures. The tectorial membrane (TM), an aECM in the cochlea mediating auditory transduction, exhibits highly ordered domain-specific architecture. α-Tectorin (TECTA), a glycosylphosphatidylinositol (GPI)-anchored ECM protein, is essential for TM organization. Here, we identified that α-tectorin is released by distinct modes: proteolytic shedding by TMPRSS2 and GPI-anchor-dependent release from the microvillus tip in mice. In the medial/limbal domain, proteolytically shed α-tectorin forms dense fibers. In contrast, in the lateral/body domain, where supporting cells exhibit dense microvilli, shedding restricts α-tectorin to the microvillus tip, compartmentalizing collagen-binding sites. Tip-localized α-tectorin is released in a GPI-anchor-dependent manner to form collagen-crosslinking fibers, maintaining the spacing and parallel organization of collagen fibrils. Overall, these distinct release modes of α-tectorin determine domain-specific organization, with the microvillus coordinating release modes along its membrane to assemble the higher-order ECM architecture.
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Affiliation(s)
- Ava Niazi
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA; Neuroscience Program, University of Utah, Salt Lake City, UT, USA
| | - Ju Ang Kim
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA
| | - Dong-Kyu Kim
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA
| | - Di Lu
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA
| | - Igal Sterin
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA
| | - Joosang Park
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA
| | - Sungjin Park
- Department of Neurobiology, University of Utah, Salt Lake City, UT, USA.
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2
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Ansel M, Ramachandran K, Dey G, Brunet T. Origin and evolution of microvilli. Biol Cell 2024; 116:e2400054. [PMID: 39233537 DOI: 10.1111/boc.202400054] [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: 05/17/2024] [Revised: 07/31/2024] [Accepted: 08/13/2024] [Indexed: 09/06/2024]
Abstract
BACKGROUND INFORMATION Microvilli are finger-like, straight, and stable cellular protrusions that are filled with F-actin and present a stereotypical length. They are present in a broad range of cell types across the animal tree of life and mediate several fundamental functions, including nutrient absorption, photosensation, and mechanosensation. Therefore, understanding the origin and evolution of microvilli is key to reconstructing the evolution of animal cellular form and function. Here, we review the current state of knowledge on microvilli evolution and perform a bioinformatic survey of the conservation of genes encoding microvillar proteins in animals and their unicellular relatives. RESULTS We first present a detailed description of mammalian microvilli based on two well-studied examples, the brush border microvilli of enterocytes and the stereocilia of hair cells. We also survey the broader diversity of microvilli and discuss similarities and differences between microvilli and filopodia. Based on our bioinformatic survey coupled with carefully reconstructed molecular phylogenies, we reconstitute the order of evolutionary appearance of microvillar proteins. We document the stepwise evolutionary assembly of the "molecular microvillar toolkit" with notable bursts of innovation at two key nodes: the last common filozoan ancestor (correlated with the evolution of microvilli distinct from filopodia) and the last common choanozoan ancestor (correlated with the emergence of inter-microvillar adhesions). CONCLUSION AND SIGNIFICANCE We conclude with a scenario for the evolution of microvilli from filopodia-like ancestral structures in unicellular precursors of animals.
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Affiliation(s)
- Mylan Ansel
- Institut Pasteur, Université Paris-Cité, CNRS UMR3691, Evolutionary Cell Biology and Evolution of Morphogenesis Unit, Paris, France
- Cell Biology and Biophysics, European Molecular Biology Laboratory, Heidelberg, Germany
- Master BioSciences, Département de Biologie, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Kaustubh Ramachandran
- Cell Biology and Biophysics, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Gautam Dey
- Cell Biology and Biophysics, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Thibaut Brunet
- Institut Pasteur, Université Paris-Cité, CNRS UMR3691, Evolutionary Cell Biology and Evolution of Morphogenesis Unit, Paris, France
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3
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Fitz GN, Tyska MJ. Molecular counting of myosin force generators in growing filopodia. J Biol Chem 2024:107934. [PMID: 39476958 DOI: 10.1016/j.jbc.2024.107934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2024] [Revised: 10/07/2024] [Accepted: 10/19/2024] [Indexed: 11/06/2024] Open
Abstract
Animal cells build actin-based surface protrusions to enable diverse biological activities, ranging from cell motility to mechanosensation to solute uptake. Long-standing models of protrusion growth suggest that actin filament polymerization provides the primary mechanical force for "pushing" the plasma membrane outward at the distal tip. Expanding on these actin-centric models, our recent studies used a chemically inducible system to establish that plasma membrane-bound myosin motors, which are abundant in protrusions and accumulate at the distal tips, can also power robust filopodial growth. How protrusion resident myosins coordinate with actin polymerization to drive elongation remains unclear, in part because the number of force generators and thus, the scale of their mechanical contributions remain undefined. To address this gap, we leveraged the SunTag system to count membrane-bound myosin motors in actively growing filopodia. Using this approach, we found that the number of myosins is log-normally distributed with a mean of 12.0 ± 2.5 motors [GeoMean ± GeoSD] per filopodium. Together with unitary force values and duty ratio estimates derived from biophysical studies for the motor used in these experiments, we calculate that a distal tip population of myosins could generate a time averaged force of ∼tens of pN to elongate filopodia. This range is comparable to the expected force production of actin polymerization in this system, a point that necessitates revision of popular physical models for protrusion growth.
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Affiliation(s)
- Gillian N Fitz
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, 528 Engineering and Science Building, 2414 Highland Ave, Nashville, TN 37232
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4
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Xu M, Rutkowski DM, Rebowski G, Boczkowska M, Pollard LW, Dominguez R, Vavylonis D, Ostap EM. Myosin-I synergizes with Arp2/3 complex to enhance the pushing forces of branched actin networks. SCIENCE ADVANCES 2024; 10:eado5788. [PMID: 39270022 PMCID: PMC11397503 DOI: 10.1126/sciadv.ado5788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 08/09/2024] [Indexed: 09/15/2024]
Abstract
Class I myosins (myosin-Is) colocalize with Arp2/3 complex-nucleated actin networks at sites of membrane protrusion and invagination, but the mechanisms by which myosin-I motor activity coordinates with branched actin assembly to generate force are unknown. We mimicked the interplay of these proteins using the "comet tail" bead motility assay, where branched actin networks are nucleated by the Arp2/3 complex on the surface of beads coated with myosin-I and nucleation-promoting factor. We observed that myosin-I increased bead movement efficiency by thinning actin networks without affecting growth rates. Myosin-I triggered symmetry breaking and comet tail formation in dense networks resistant to spontaneous fracturing. Even with arrested actin assembly, myosin-I alone could break the network. Computational modeling recapitulated these observations, suggesting myosin-I acts as a repulsive force shaping the network's architecture and boosting its force-generating capacity. We propose that myosin-I leverages its power stroke to amplify the forces generated by Arp2/3 complex-nucleated actin networks.
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Affiliation(s)
- Mengqi Xu
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Grzegorz Rebowski
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Malgorzata Boczkowska
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Luther W. Pollard
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Roberto Dominguez
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - E. Michael Ostap
- Department of Physiology, Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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5
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Wright M, Redford S, Vehar J, Courtney KC, Billington N, Liu R. MultiBac System-based Purification and Biophysical Characterization of Human Myosin-7a. J Vis Exp 2024:10.3791/67135. [PMID: 39248532 PMCID: PMC11633084 DOI: 10.3791/67135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2024] Open
Abstract
Myosin-7a is an actin-based motor protein vital for auditory and visual processes. Mutations in myosin-7a lead to Usher syndrome type 1, the most common and severe form of deaf-blindness in humans. It is hypothesized that myosin-7a forms a transmembrane adhesion complex with other Usher proteins, essential for the structural-functional integrity of photoreceptor and cochlear hair cells. However, due to the challenges in obtaining pure, intact protein, the exact functional mechanisms of human myosin-7a remain elusive, with limited structural and biomechanical studies available. Recent studies have shown that mammalian myosin-7a is a multimeric motor complex consisting of a heavy chain and three types of light chains: regulatory light chain (RLC), calmodulin, and calmodulin-like protein 4 (CALML4). Unlike calmodulin, CALML4 does not bind to calcium ions. Both the calcium-sensitive, and insensitive calmodulins are critical for mammalian myosin-7a for proper fine-tuning of its mechanical properties. Here, we describe a detailed method to produce recombinant human myosin-7a holoenzyme using the MultiBac Baculovirus protein expression system. This yields milligram quantities of high-purity full-length protein, allowing for its biochemical and biophysical characterization. We further present a protocol for assessing its mechanical and motile properties using tailored in vitro motility assays and fluorescence microscopy. The availability of the intact human myosin-7a protein, along with the detailed functional characterization protocol described here, paves the way for further investigations into the molecular aspects of myosin-7a in vision and hearing.
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Affiliation(s)
- Marvin Wright
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University
| | - Shayna Redford
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University
| | - Jacob Vehar
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University
| | - Kevin C Courtney
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University
| | - Neil Billington
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University; Microscope Imaging Facility, West Virginia University
| | - Rong Liu
- Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University;
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6
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Tsai FC, Guérin G, Pernier J, Bassereau P. Actin-membrane linkers: Insights from synthetic reconstituted systems. Eur J Cell Biol 2024; 103:151402. [PMID: 38461706 DOI: 10.1016/j.ejcb.2024.151402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 02/10/2024] [Accepted: 02/28/2024] [Indexed: 03/12/2024] Open
Abstract
At the cell surface, the actin cytoskeleton and the plasma membrane interact reciprocally in a variety of processes related to the remodeling of the cell surface. The actin cytoskeleton has been known to modulate membrane organization and reshape the membrane. To this end, actin-membrane linking molecules play a major role in regulating actin assembly and spatially direct the interaction between the actin cytoskeleton and the membrane. While studies in cells have provided a wealth of knowledge on the molecular composition and interactions of the actin-membrane interface, the complex molecular interactions make it challenging to elucidate the precise actions of the actin-membrane linkers at the interface. Synthetic reconstituted systems, consisting of model membranes and purified proteins, have been a powerful approach to elucidate how actin-membrane linkers direct actin assembly to drive membrane shape changes. In this review, we will focus only on several actin-membrane linkers that have been studied by using reconstitution systems. We will discuss the design principles of these reconstitution systems and how they have contributed to the understanding of the cellular functions of actin-membrane linkers. Finally, we will provide a perspective on future research directions in understanding the intricate actin-membrane interaction.
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Affiliation(s)
- Feng-Ching Tsai
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Physics of Cells and Cancer, Paris 75005, France.
| | - Gwendal Guérin
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Physics of Cells and Cancer, Paris 75005, France
| | - Julien Pernier
- Tumor Cell Dynamics Unit, Inserm U1279, Gustave Roussy Institute, Université Paris-Saclay, Villejuif 94800, France
| | - Patricia Bassereau
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Physics of Cells and Cancer, Paris 75005, France.
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7
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Miyoshi T, Vishwasrao H, Belyantseva I, Sajeevadathan M, Ishibashi Y, Adadey S, Harada N, Shroff H, Friedman T. Live-cell single-molecule fluorescence microscopy for protruding organelles reveals regulatory mechanisms of MYO7A-driven cargo transport in stereocilia of inner ear hair cells. RESEARCH SQUARE 2024:rs.3.rs-4369958. [PMID: 38826223 PMCID: PMC11142366 DOI: 10.21203/rs.3.rs-4369958/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Stereocilia are unidirectional F-actin-based cylindrical protrusions on the apical surface of inner ear hair cells and function as biological mechanosensors of sound and acceleration. Development of functional stereocilia requires motor activities of unconventional myosins to transport proteins necessary for elongating the F-actin cores and to assemble the mechanoelectrical transduction (MET) channel complex. However, how each myosin localizes in stereocilia using the energy from ATP hydrolysis is only partially understood. In this study, we develop a methodology for live-cell single-molecule fluorescence microscopy of organelles protruding from the apical surface using a dual-view light-sheet microscope, diSPIM. We demonstrate that MYO7A, a component of the MET machinery, traffics as a dimer in stereocilia. Movements of MYO7A are restricted when scaffolded by the plasma membrane and F-actin as mediated by MYO7A's interacting partners. Here, we discuss the technical details of our methodology and its future applications including analyses of cargo transportation in various organelles.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Thomas Friedman
- National Institute on Deafness and Other Communication Disorders, NIH
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8
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Fitz GN, Tyska MJ. Molecular counting of myosin force generators in growing filopodia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.14.593924. [PMID: 38798618 PMCID: PMC11118519 DOI: 10.1101/2024.05.14.593924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Animal cells build actin-based surface protrusions to enable biological activities ranging from cell motility to mechanosensation to solute uptake. Long-standing models of protrusion growth suggest that actin filament polymerization provides the primary mechanical force for "pushing" the plasma membrane outward at the distal tip. Expanding on these actin-centric models, our recent studies used a chemically inducible system to establish that plasma membrane-bound myosin motors, which are abundant in protrusions and accumulate at the distal tips, can also power robust filopodial growth. How protrusion resident myosins coordinate with actin polymerization to drive elongation remains unclear, in part because the number of force generators and thus, the scale of their mechanical contributions remain undefined. To address this gap, we leveraged the SunTag system to count membrane-bound myosin motors in actively growing filopodia. Using this approach, we found that the number of myosins is log-normally distributed with a mean of 12.0 ± 2.5 motors [GeoMean ± GeoSD] per filopodium. Together with unitary force values and duty ratio estimates derived from biophysical studies for the motor used in these experiments, we calculate that a distal tip population of myosins could generate a time averaged force of ∼tens of pN to elongate filopodia. This range is comparable to the expected force production of actin polymerization in this system, a point that necessitates revision of popular physical models for protrusion growth. SIGNIFICANCE STATEMENT This study describes the results of in-cell molecular counting experiments to define the number of myosin motors that are mechanically active in growing filopodia. This data should be used to constrain future physical models of the formation of actin-based protrusions.
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9
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Miyoshi T, Vishwasrao HD, Belyantseva IA, Sajeevadathan M, Ishibashi Y, Adadey SM, Harada N, Shroff H, Friedman TB. Live-cell single-molecule fluorescence microscopy for protruding organelles reveals regulatory mechanisms of MYO7A-driven cargo transport in stereocilia of inner ear hair cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.04.590649. [PMID: 38766013 PMCID: PMC11100596 DOI: 10.1101/2024.05.04.590649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Stereocilia are unidirectional F-actin-based cylindrical protrusions on the apical surface of inner ear hair cells and function as biological mechanosensors of sound and acceleration. Development of functional stereocilia requires motor activities of unconventional myosins to transport proteins necessary for elongating the F-actin cores and to assemble the mechanoelectrical transduction (MET) channel complex. However, how each myosin localizes in stereocilia using the energy from ATP hydrolysis is only partially understood. In this study, we develop a methodology for live-cell single-molecule fluorescence microscopy of organelles protruding from the apical surface using a dual-view light-sheet microscope, diSPIM. We demonstrate that MYO7A, a component of the MET machinery, traffics as a dimer in stereocilia. Movements of MYO7A are restricted when scaffolded by the plasma membrane and F-actin as mediated by MYO7A's interacting partners. Here, we discuss the technical details of our methodology and its future applications including analyses of cargo transportation in various organelles.
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Affiliation(s)
- Takushi Miyoshi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
- Division of Molecular and Integrative Physiology, Department of Biomedical Sciences, Southern Illinois University School of Medicine, Carbondale, IL, 62901, USA
| | - Harshad D. Vishwasrao
- Advanced Imaging and Microscopy Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Inna A. Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mrudhula Sajeevadathan
- Division of Molecular and Integrative Physiology, Department of Biomedical Sciences, Southern Illinois University School of Medicine, Carbondale, IL, 62901, USA
| | - Yasuko Ishibashi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institute of Health, Bethesda, Maryland 20892, USA
| | - Samuel M. Adadey
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Narinobu Harada
- Hearing Research Laboratory, Harada ENT Clinic, Higashi-Osaka, Osaka, 577-0816, Japan
| | - Hari Shroff
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
| | - Thomas B. Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
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Shadab M, Abbasi AA, Ejaz A, Ben-Mahmoud A, Gupta V, Kim HG, Vona B. Autosomal recessive non-syndromic hearing loss genes in Pakistan during the previous three decades. J Cell Mol Med 2024; 28:e18119. [PMID: 38534090 DOI: 10.1111/jcmm.18119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 11/29/2023] [Accepted: 01/02/2024] [Indexed: 03/28/2024] Open
Abstract
Hearing loss is a clinically and genetically heterogeneous disorder, with over 148 genes and 170 loci associated with its pathogenesis. The spectrum and frequency of causal variants vary across different genetic ancestries and are more prevalent in populations that practice consanguineous marriages. Pakistan has a rich history of autosomal recessive gene discovery related to non-syndromic hearing loss. Since the first linkage analysis with a Pakistani family that led to the mapping of the DFNB1 locus on chromosome 13, 51 genes associated with this disorder have been identified in this population. Among these, 13 of the most prevalent genes, namely CDH23, CIB2, CLDN14, GJB2, HGF, MARVELD2, MYO7A, MYO15A, MSRB3, OTOF, SLC26A4, TMC1 and TMPRSS3, account for more than half of all cases of profound hearing loss, while the prevalence of other genes is less than 2% individually. In this review, we discuss the most common autosomal recessive non-syndromic hearing loss genes in Pakistani individuals as well as the genetic mapping and sequencing approaches used to discover them. Furthermore, we identified enriched gene ontology terms and common pathways involved in these 51 autosomal recessive non-syndromic hearing loss genes to gain a better understanding of the underlying mechanisms. Establishing a molecular understanding of the disorder may aid in reducing its future prevalence by enabling timely diagnostics and genetic counselling, leading to more effective clinical management and treatments of hearing loss.
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Affiliation(s)
- Madiha Shadab
- Department of Zoology, Mirpur University of Science and Technology, Mirpur, Pakistan
| | - Ansar Ahmed Abbasi
- Department of Zoology, Mirpur University of Science and Technology, Mirpur, Pakistan
| | - Ahsan Ejaz
- Department of Physics, University of Kotli Azad Jammu and Kashmir, Kotli, Pakistan
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, China
| | - Afif Ben-Mahmoud
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Doha, Qatar
| | - Vijay Gupta
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Doha, Qatar
| | - Hyung-Goo Kim
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Doha, Qatar
- College of Health & Life Sciences, Hamad Bin Khalifa University (HBKU), Doha, Qatar
| | - Barbara Vona
- Institute of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
- Institute for Auditory Neuroscience and Inner Ear Lab, University Medical Center Göttingen, Göttingen, Germany
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11
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Miyoshi T, Belyantseva IA, Sajeevadathan M, Friedman TB. Pathophysiology of human hearing loss associated with variants in myosins. Front Physiol 2024; 15:1374901. [PMID: 38562617 PMCID: PMC10982375 DOI: 10.3389/fphys.2024.1374901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 02/21/2024] [Indexed: 04/04/2024] Open
Abstract
Deleterious variants of more than one hundred genes are associated with hearing loss including MYO3A, MYO6, MYO7A and MYO15A and two conventional myosins MYH9 and MYH14. Variants of MYO7A also manifest as Usher syndrome associated with dysfunction of the retina and vestibule as well as hearing loss. While the functions of MYH9 and MYH14 in the inner ear are debated, MYO3A, MYO6, MYO7A and MYO15A are expressed in inner ear hair cells along with class-I myosin MYO1C and are essential for developing and maintaining functional stereocilia on the apical surface of hair cells. Stereocilia are large, cylindrical, actin-rich protrusions functioning as biological mechanosensors to detect sound, acceleration and posture. The rigidity of stereocilia is sustained by highly crosslinked unidirectionally-oriented F-actin, which also provides a scaffold for various proteins including unconventional myosins and their cargo. Typical myosin molecules consist of an ATPase head motor domain to transmit forces to F-actin, a neck containing IQ-motifs that bind regulatory light chains and a tail region with motifs recognizing partners. Instead of long coiled-coil domains characterizing conventional myosins, the tails of unconventional myosins have various motifs to anchor or transport proteins and phospholipids along the F-actin core of a stereocilium. For these myosins, decades of studies have elucidated their biochemical properties, interacting partners in hair cells and variants associated with hearing loss. However, less is known about how myosins traffic in a stereocilium using their motor function, and how each variant correlates with a clinical condition including the severity and onset of hearing loss, mode of inheritance and presence of symptoms other than hearing loss. Here, we cover the domain structures and functions of myosins associated with hearing loss together with advances, open questions about trafficking of myosins in stereocilia and correlations between hundreds of variants in myosins annotated in ClinVar and the corresponding deafness phenotypes.
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Affiliation(s)
- Takushi Miyoshi
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
- Division of Molecular and Integrative Physiology, Department of Biomedical Sciences, Southern Illinois University School of Medicine, Carbondale, IL, United States
| | - Inna A. Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
| | - Mrudhula Sajeevadathan
- Division of Molecular and Integrative Physiology, Department of Biomedical Sciences, Southern Illinois University School of Medicine, Carbondale, IL, United States
| | - Thomas B. Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, United States
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12
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Yim YI, Pedrosa A, Wu X, Chinthalapudi K, Cheney RE, Hammer JA. Mechanisms underlying Myosin 10's contribution to the maintenance of mitotic spindle bipolarity. Mol Biol Cell 2024; 35:ar14. [PMID: 38019611 PMCID: PMC10881153 DOI: 10.1091/mbc.e23-07-0282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/13/2023] [Accepted: 11/17/2023] [Indexed: 12/01/2023] Open
Abstract
Myosin 10 (Myo10) couples microtubules and integrin-based adhesions to movement along actin filaments via its microtubule-binding MyTH4 domain and integrin-binding FERM domain, respectively. Here we show that Myo10-depleted HeLa cells and mouse embryo fibroblasts (MEFs) both exhibit a pronounced increase in the frequency of multipolar spindles. Staining of unsynchronized metaphase cells showed that the primary driver of spindle multipolarity in Myo10-depleted MEFs and in Myo10-depleted HeLa cells lacking supernumerary centrosomes is pericentriolar material (PCM) fragmentation, which creates y-tubulin-positive acentriolar foci that serve as extra spindle poles. For HeLa cells possessing supernumerary centrosomes, Myo10 depletion further accentuates spindle multipolarity by impairing the clustering of the extra spindle poles. Complementation experiments show that Myo10 must interact with both microtubules and integrins to promote PCM/pole integrity. Conversely, Myo10 only needs interact with integrins to promote supernumerary centrosome clustering. Importantly, images of metaphase Halo-Myo10 knockin cells show that the myosin localizes exclusively to the spindle and the tips of adhesive retraction fibers. We conclude that Myo10 promotes PCM/pole integrity in part by interacting with spindle microtubules, and that it promotes supernumerary centrosome clustering by supporting retraction fiber-based cell adhesion, which likely serves to anchor the microtubule-based forces driving pole focusing.
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Affiliation(s)
- Yang-In Yim
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Antonio Pedrosa
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Xufeng Wu
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Krishna Chinthalapudi
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210
| | - Richard E. Cheney
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27599
| | - John A. Hammer
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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Niazi A, Kim JA, Kim DK, Lu D, Sterin I, Park J, Park S. Microvilli regulate the release modes of alpha-tectorin to organize the domain-specific matrix architecture of the tectorial membrane. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.04.574255. [PMID: 38260557 PMCID: PMC10802356 DOI: 10.1101/2024.01.04.574255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The tectorial membrane (TM) is an apical extracellular matrix (ECM) in the cochlea essential for auditory transduction. The TM exhibits highly ordered domain-specific architecture. Alpha-tectorin/TECTA is a glycosylphosphatidylinositol (GPI)-anchored ECM protein essential for TM organization. Here, we identified that TECTA is released by distinct modes: proteolytic shedding by TMPRSS2 and GPI-anchor-dependent release from the microvillus tip. In the medial/limbal domain, proteolytically shed TECTA forms dense fibers. In the lateral/body domain produced by the supporting cells displaying dense microvilli, the proteolytic shedding restricts TECTA to the microvillus tip and compartmentalizes the collagen-binding site. The tip-localized TECTA, in turn, is released in a GPI-anchor-dependent manner to form collagen-crosslinking fibers, required for maintaining the spacing and parallel organization of collagen fibrils. Overall, we showed that distinct release modes of TECTA determine the domain-specific organization pattern, and the microvillus coordinates the release modes along its membrane to organize the higher-order ECM architecture.
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Affiliation(s)
- Ava Niazi
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
- Neuroscience Program, University of Utah, Salt Lake City, Utah, USA
| | - Ju Ang Kim
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
- Current affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Dong-Kyu Kim
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
- Current affiliation: Genetics & Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Di Lu
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
| | - Igal Sterin
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
| | - Joosang Park
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
| | - Sungjin Park
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
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14
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Ru Y, Dong S, Liu J, Liu J, Eyden B. Structural characterization and origin of surface vesicles in monocytes: another membranous pathway from cytoplasm to cell surface. Ultrastruct Pathol 2024; 48:56-65. [PMID: 38037244 DOI: 10.1080/01913123.2023.2286972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 11/20/2023] [Indexed: 12/02/2023]
Abstract
The monocytes in acute monocytic leukemia (AML-M5b) were analyzed by scanning and transmission electron microscopy (SEM and TEM) to understand more fully their structure and origin. By SEM, monocytes exhibited localized expansions of the surface, some of which appeared to bud off as surface vesicles (SVs). Filopodial processes and pseudopodia were also present. TEM demonstrated that the SVs were composed of a double-membrane at the pole away from the cell body, and a single membrane nearer to the cell body. In the peripheral cytoplasm, intracellular vesicles (IVs) had the appearance of vacuoles and were enclosed by single membranes. Most SVs were characterized by a notch as a rER edge and an expanded head. Filopodial processes had the same thickness of 40 nm as the SV walls, which suggested a close developmental relationship between the two. Pseudopodia between SVs were irregular in size. Rod-like rER cisternae were prominent in the peripheral cytoplasm and some showed a close physical juxtaposition as to suggest a transition from rER to IVs to SVs. Ultrastructural cytochemistry demonstrated activity of 5'-nucleotidase over rER, SVs, filopodial processes and pseudopodia, and a patchy reaction over other areas of plasma membrane. Overall, the results indicated that rER transforms into SVs, filopodial processes and pseudopodia, as a way of integrating cytoplasmic membranes into the plasma membrane.
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Affiliation(s)
- Yongxin Ru
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of the Cell Ecosystem, Institute of Hematology&Blood Diseases Hospital, Chinese Academy of Medical Sciences &Peking Union Medical College, Tianjin, China
- Tianjin Institutes of Health Science, Tianjin, China
| | - Shuxu Dong
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of the Cell Ecosystem, Institute of Hematology&Blood Diseases Hospital, Chinese Academy of Medical Sciences &Peking Union Medical College, Tianjin, China
- Tianjin Institutes of Health Science, Tianjin, China
| | - Jing Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of the Cell Ecosystem, Institute of Hematology&Blood Diseases Hospital, Chinese Academy of Medical Sciences &Peking Union Medical College, Tianjin, China
- Tianjin Institutes of Health Science, Tianjin, China
| | - Jinhua Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of the Cell Ecosystem, Institute of Hematology&Blood Diseases Hospital, Chinese Academy of Medical Sciences &Peking Union Medical College, Tianjin, China
- Tianjin Institutes of Health Science, Tianjin, China
| | - Brian Eyden
- Department of Histopathology, Christie NHS Foundation Trust, Manchester, UK
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15
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Al-Zahaby SA, Hassan SS, Elsheikh EH. Ultramicroscopic organization of the exterior olfactory organ in Anguilla vulgaris in relation to its spawning migration. Open Vet J 2024; 14:512-524. [PMID: 38633152 PMCID: PMC11018411 DOI: 10.5455/ovj.2024.v14.i1.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 12/15/2023] [Indexed: 04/19/2024] Open
Abstract
Background Catadromous fishes have well-developed elongated olfactory organs with numerous lamellae and different types of receptor neurons related to their breeding migration. Aim The current study showed how the olfactory system adapted to the catadromous life. Our work declared the need of the migratory fishes for the sense of smell that is exhibited by a higher number of the olfactory lamellae and the receptor neuron verification in the olfactory epithelium. Methods Ten specimens of fully grown, but pre-matured, silver eels of Anguilla vulgaris were captured at the outlet of Edco Lake, overlooking the Mediterranean Sea, east of Alexandria. Olfactory rosettes were dissected and fixed for scanning electron microscope (SEM) and transmission electron microscope (TEM). Results Our study gave a morphological description of the olfactory system of A. vulgaris. At the ultrastructural level using SEM and TEM, one olfactory rosette was provided with 90-100 flat radial olfactory lamellae. The nasal configuration allowed water to enter and exit, transferring odorant molecules to olfactory receptor cells which comprise long cylindrical ciliated and microvillous receptors as well as rod-tipped cells. These cells are bipolar neurons with upward dendritic knobs. The olfactory epithelia also include crypt receptor cells. Interestingly, the olfactory neurons are delimited by nonsensory supporting cells, including long motile kinocilia and sustentacular supporting cells beside mucus secretory goblet cells and ionocytes or labyrinth cells that contribute to the olfaction process. Conclusion Olfaction is crucial in all vertebrates, including fishes as it involves reproduction, parental, feeding, defensive, schooling, and migration behaviors. Here, A. vulgaris is an excellent model for catadromous fishes. It has a well-developed olfactory organ to cope with the dramatic climate change, habitat loss, water pollution, and altered ocean currents effect during their catadromous life for reproduction.
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Affiliation(s)
| | - Sahar S. Hassan
- Zoology Department, Faculty of Science, Zagazig University, Zagazig, Egypt
| | - Eman H. Elsheikh
- Zoology Department, Faculty of Science, Zagazig University, Zagazig, Egypt
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16
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Liu H, Shen W, Liu W, Yang Z, Yin D, Xiao C. From oncolytic peptides to oncolytic polymers: A new paradigm for oncotherapy. Bioact Mater 2024; 31:206-230. [PMID: 37637082 PMCID: PMC10450358 DOI: 10.1016/j.bioactmat.2023.08.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 07/18/2023] [Accepted: 08/08/2023] [Indexed: 08/29/2023] Open
Abstract
Traditional cancer therapy methods, especially those directed against specific intracellular targets or signaling pathways, are not powerful enough to overcome tumor heterogeneity and therapeutic resistance. Oncolytic peptides that can induce membrane lysis-mediated cancer cell death and subsequent anticancer immune responses, has provided a new paradigm for cancer therapy. However, the clinical application of oncolytic peptides is always limited by some factors such as unsatisfactory bio-distribution, poor stability, and off-target toxicity. To overcome these limitations, oncolytic polymers stand out as prospective therapeutic materials owing to their high stability, chemical versatility, and scalable production capacity, which has the potential to drive a revolution in cancer treatment. This review provides an overview of the mechanism and structure-activity relationship of oncolytic peptides. Then the oncolytic peptides-mediated combination therapy and the nano-delivery strategies for oncolytic peptides are summarized. Emphatically, the current research progress of oncolytic polymers has been highlighted. Lastly, the challenges and prospects in the development of oncolytic polymers are discussed.
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Affiliation(s)
- Hanmeng Liu
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, 230012, China
| | - Wei Shen
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, 230012, China
- Anhui Province Key Laboratory of Pharmaceutical Preparation Technology and Application, Hefei, Anhui, 230012, China
- Engineering Technology Research Center of Modernized Pharmaceutics, Anhui Education Department (AUCM), Hefei, Anhui, 230012, China
| | - Wanguo Liu
- Department of Orthopaedic Surgery, China-Japan Union Hospital, Jilin University, Changchun, 130033, China
| | - Zexin Yang
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, 230012, China
| | - Dengke Yin
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, 230012, China
- Engineering Technology Research Center of Modernized Pharmaceutics, Anhui Education Department (AUCM), Hefei, Anhui, 230012, China
| | - Chunsheng Xiao
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
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17
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Cassau S, Krieger J. Evidence for a role of SNMP2 and antennal support cells in sensillum lymph clearance processes of moth pheromone-responsive sensilla. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 164:104046. [PMID: 38043913 DOI: 10.1016/j.ibmb.2023.104046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/10/2023] [Accepted: 11/28/2023] [Indexed: 12/05/2023]
Abstract
In insect antenna, following the activation of olfactory sensory neurons, odorant molecules are inactivated by enzymes in the sensillum lymph. How the inactivation products are cleared from the sensillum lymph is presently unknown. Here we studied the role of support cells (SCs) and the so-called sensory neuron membrane protein 2 (SNMP2), a member of the CD36 family of lipid transporters abundantly expressed in SCs, in sensillum lymph clearance processes in the moths Heliothis virescens and Bombyx mori. In these species, the sex pheromone components are inactivated to long-chain fatty acids. To approach a role of SNMP2 in the removal of such inactivation products, we analyzed the uptake of a fluorescent long-chain fatty acid analog into a newly generated HvirSNMP2-expressing cell line. We found an increased uptake of the analog into SNMP2-cells compared to control cells, which could be blocked by the CD36 protein inhibitor, SSO. Furthermore, analyses of sensilla from antenna treated with the fatty acid analog indicated that SNMP2-expressing SCs are able to take up fatty acids from the sensillum lymph. In addition, sensilla from SSO-pretreated antenna of B. mori showed reduced removal of the fluorescent analog from the sensillum lymph. Finally, we revealed that SSO pretreatment of male silkmoth antenna significantly prolonged the duration of the female pheromone-induced wing-fluttering behavior, possibly as a result of impaired lymph clearance processes. Together our findings in H. virescens and B. mori support a pivotal role of olfactory SCs in sensillum lymph maintenance processes and suggest an integral role of SNMP2 in the removal of lipophilic "waste products" such as fatty acids resulting from sex pheromone inactivation.
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Affiliation(s)
- Sina Cassau
- Martin Luther University Halle-Wittenberg, Institute of Biology/Zoology, Department of Animal Physiology, 06120 Halle (Saale), Germany.
| | - Jürgen Krieger
- Martin Luther University Halle-Wittenberg, Institute of Biology/Zoology, Department of Animal Physiology, 06120 Halle (Saale), Germany.
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18
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Chen X, Arciola JM, Lee YI, Wong PHP, Yin H, Tao Q, Jin Y, Qin X, Sweeney HL, Park H. Myo10 tail is crucial for promoting long filopodia. J Biol Chem 2024; 300:105523. [PMID: 38043799 PMCID: PMC10790087 DOI: 10.1016/j.jbc.2023.105523] [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: 07/03/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 12/05/2023] Open
Abstract
Filopodia are slender cellular protrusions containing parallel actin bundles involved in environmental sensing and signaling, cell adhesion and migration, and growth cone guidance and extension. Myosin 10 (Myo10), an unconventional actin-based motor protein, was reported to induce filopodial initiation with its motor domain. However, the roles of the multifunctional tail domain of Myo10 in filopodial formation and elongation remain elusive. Herein, we generated several constructs of Myo10-full-length Myo10, Myo10 with a truncated tail (Myo10 HMM), and Myo10 containing four mutations to disrupt its coiled-coil domain (Myo10 CC mutant). We found that the truncation of the tail domain decreased filopodial formation and filopodial length, while four mutations in the coiled-coil domain disrupted the motion of Myo10 toward filopodial tips and the elongation of filopodia. Furthermore, we found that filopodia elongated through multiple elongation cycles, which was supported by the Myo10 tail. These findings suggest that Myo10 tail is crucial for promoting long filopodia.
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Affiliation(s)
- Xingxiang Chen
- Division of Life Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | | | - Young Il Lee
- Department of Pharmacology & Therapeutics, University of Florida College of Medicine, Gainesville, USA
| | - Pak Hung Philip Wong
- Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Haoran Yin
- Division of Life Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Quanqing Tao
- Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Yuqi Jin
- Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Xianan Qin
- Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - H Lee Sweeney
- Department of Pharmacology & Therapeutics, University of Florida College of Medicine, Gainesville, USA; Myology Institute, University of Florida College of Medicine, Gainesville, Florida, USA.
| | - Hyokeun Park
- Division of Life Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China; Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China.
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19
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Suarez C, Winkelman JD, Harker AJ, Ye HJ, McCall PM, Morganthaler AN, Gardel ML, Kovar DR. Reconstitution of the transition from a lamellipodia- to filopodia-like actin network with purified proteins. Eur J Cell Biol 2023; 102:151367. [PMID: 37890285 DOI: 10.1016/j.ejcb.2023.151367] [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: 06/22/2023] [Revised: 09/29/2023] [Accepted: 10/19/2023] [Indexed: 10/29/2023] Open
Abstract
How cells utilize complex mixtures of actin binding proteins to assemble and maintain functionally diverse actin filament networks with distinct architectures and dynamics within a common cytoplasm is a longstanding question in cell biology. A compelling example of complex and specialized actin structures in cells are filopodia which sense extracellular chemical and mechanical signals to help steer motile cells. Filopodia have distinct actin architecture, composed of long, parallel actin filaments bundled by fascin, which form finger-like membrane protrusions. Elongation of the parallel actin filaments in filopodia can be mediated by two processive actin filament elongation factors, formin and Ena/VASP, which localize to the tips of filopodia. There remains debate as to how the architecture of filopodia are generated, with one hypothesis proposing that filopodia are generated from the lamellipodia, which consists of densely packed, branched actin filaments nucleated by Arp2/3 complex and kept short by capping protein. It remains unclear if different actin filament elongation factors are necessary and sufficient to facilitate the emergence of filopodia with diverse characteristics from a highly dense network of short-branched capped filaments. To address this question, we combined bead motility and micropatterning biomimetic assays with multi-color Total Internal Reflection Fluorescence microscopy imaging, to successfully reconstitute the formation of filopodia-like networks (FLN) from densely-branched lamellipodia-like networks (LLN) with eight purified proteins (actin, profilin, Arp2/3 complex, Wasp pWA, fascin, capping protein, VASP and formin mDia2). Saturating capping protein concentrations inhibit FLN assembly, but the addition of either formin or Ena/VASP differentially rescues the formation of FLN from LLN. Specifically, we found that formin/mDia2-generated FLNs are relatively long and lack capping protein, whereas VASP-generated FLNs are comparatively short and contain capping protein, indicating that the actin elongation factor can affect the architecture and composition of FLN emerging from LLN. Our biomimetic reconstitution systems reveal that formin or VASP are necessary and sufficient to induce the transition from a LLN to a FLN, and establish robust in vitro platforms to investigate FLN assembly mechanisms.
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Affiliation(s)
- Cristian Suarez
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA.
| | - Jonathan D Winkelman
- Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA
| | - Alyssa J Harker
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Hannah J Ye
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Patrick M McCall
- Department of Physics, The University of Chicago, Chicago, IL 60637, USA; James Franck Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Alisha N Morganthaler
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Margaret L Gardel
- Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA; Department of Physics, The University of Chicago, Chicago, IL 60637, USA; James Franck Institute, The University of Chicago, Chicago, IL 60637, USA; Pritzker School for Molecular Engineering, The University of Chicago, Chicago, IL 60637, USA
| | - David R Kovar
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA; Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
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20
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Holló A, Billington N, Takagi Y, Kengyel A, Sellers JR, Liu R. Molecular regulatory mechanism of human myosin-7a. J Biol Chem 2023; 299:105243. [PMID: 37690683 PMCID: PMC10579538 DOI: 10.1016/j.jbc.2023.105243] [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: 06/23/2023] [Revised: 09/01/2023] [Accepted: 09/04/2023] [Indexed: 09/12/2023] Open
Abstract
Myosin-7a is an actin-based motor protein essential for vision and hearing. Mutations of myosin-7a cause type 1 Usher syndrome, the most common and severe form of deafblindness in humans. The molecular mechanisms that govern its mechanochemistry remain poorly understood, primarily because of the difficulty of purifying stable intact protein. Here, we recombinantly produce the complete human myosin-7a holoenzyme in insect cells and characterize its biochemical and motile properties. Unlike the Drosophila ortholog that primarily associates with calmodulin (CaM), we found that human myosin-7a utilizes a unique combination of light chains including regulatory light chain, CaM, and CaM-like protein 4. Our results further reveal that CaM-like protein 4 does not function as a Ca2+ sensor but plays a crucial role in maintaining the lever arm's structural-functional integrity. Using our recombinant protein system, we purified two myosin-7a splicing isoforms that have been shown to be differentially expressed along the cochlear tonotopic axis. We show that they possess distinct mechanoenzymatic properties despite differing by only 11 amino acids at their N termini. Using single-molecule in vitro motility assays, we demonstrate that human myosin-7a exists as an autoinhibited monomer and can move processively along actin when artificially dimerized or bound to cargo adaptor proteins. These results suggest that myosin-7a can serve multiple roles in sensory systems such as acting as a transporter or an anchor/force sensor. Furthermore, our research highlights that human myosin-7a has evolved unique regulatory elements that enable precise tuning of its mechanical properties suitable for mammalian auditory functions.
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Affiliation(s)
- Alexandra Holló
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biophysics, University of Pécs Medical School, Pécs, Hungary
| | - Neil Billington
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia, USA; Microscope Imaging Facility, West Virginia University, Morgantown, West Virginia, USA
| | - Yasuharu Takagi
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - András Kengyel
- Department of Biophysics, University of Pécs Medical School, Pécs, Hungary; Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
| | - Rong Liu
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA; Department of Biochemistry & Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia, USA.
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21
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Li W, Chung WL, Kozlov MM, Medalia O, Geiger B, Bershadsky AD. Chiral growth of adherent filopodia. Biophys J 2023; 122:3704-3721. [PMID: 37301982 PMCID: PMC10541518 DOI: 10.1016/j.bpj.2023.06.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/03/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023] Open
Abstract
Adherent filopodia are elongated finger-like membrane protrusions, extending from the edges of diverse cell types and participating in cell adhesion, spreading, migration, and environmental sensing. The formation and elongation of filopodia are driven by the polymerization of parallel actin filaments, comprising the filopodia cytoskeletal core. Here, we report that adherent filopodia, formed during the spreading of cultured cells on galectin-8-coated substrates, tend to change the direction of their extension in a chiral fashion, acquiring a left-bent shape. Cryoelectron tomography examination indicated that turning of the filopodia tip to the left is accompanied by the displacement of the actin core bundle to the right of the filopodia midline. Reduction of the adhesion to galectin-8 by treatment with thiodigalactoside abolished this filopodia chirality. By modulating the expression of a variety of actin-associated filopodia proteins, we identified myosin-X and formin DAAM1 as major filopodia chirality promoting factors. Formin mDia1, actin filament elongation factor VASP, and actin filament cross-linker fascin were also shown to be involved. Thus, the simple actin cytoskeleton of filopodia, together with a small number of associated proteins are sufficient to drive a complex navigation process, manifested by the development of left-right asymmetry in these cellular protrusions.
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Affiliation(s)
- Wenhong Li
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Wen-Lu Chung
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Benjamin Geiger
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
| | - Alexander D Bershadsky
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel; Mechanobiology Institute, National University of Singapore, Singapore, Singapore.
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22
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Yim YI, Pedrosa A, Wu X, Chinthalapudi K, Cheney RE, Hammer JA. Myosin 10 uses its MyTH4 and FERM domains differentially to support two aspects of spindle pole biology required for mitotic spindle bipolarity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.15.545002. [PMID: 37398378 PMCID: PMC10312724 DOI: 10.1101/2023.06.15.545002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Myosin 10 (Myo10) has the ability to link actin filaments to integrin-based adhesions and to microtubules by virtue of its integrin-binding FERM domain and microtubule-binding MyTH4 domain, respectively. Here we used Myo10 knockout cells to define Myo10's contribution to the maintenance of spindle bipolarity, and complementation to quantitate the relative contributions of its MyTH4 and FERM domains. Myo10 knockout HeLa cells and mouse embryo fibroblasts (MEFs) both exhibit a pronounced increase in the frequency of multipolar spindles. Staining of unsynchronized metaphase cells showed that the primary driver of spindle multipolarity in knockout MEFs and knockout HeLa cells lacking supernumerary centrosomes is pericentriolar material (PCM) fragmentation, which creates γ-tubulin-positive acentriolar foci that serve as additional spindle poles. For HeLa cells possessing supernumerary centrosomes, Myo10 depletion further accentuates spindle multipolarity by impairing the clustering of the extra spindle poles. Complementation experiments show that Myo10 must interact with both integrins and microtubules to promote PCM/pole integrity. Conversely, Myo10's ability to promote the clustering of supernumerary centrosomes only requires that it interact with integrins. Importantly, images of Halo-Myo10 knock-in cells show that the myosin localizes exclusively within adhesive retraction fibers during mitosis. Based on these and other results, we conclude that Myo10 promotes PCM/pole integrity at a distance, and that it facilitates supernumerary centrosome clustering by promoting retraction fiber-based cell adhesion, which likely provides an anchor for the microtubule-based forces driving pole focusing.
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Affiliation(s)
- Yang-In Yim
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Antonio Pedrosa
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Xufeng Wu
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Krishna Chinthalapudi
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH
| | - Richard E. Cheney
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC
| | - John A. Hammer
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
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Innocenti M. Investigating Mammalian Formins with SMIFH2 Fifteen Years in: Novel Targets and Unexpected Biology. Int J Mol Sci 2023; 24:ijms24109058. [PMID: 37240404 DOI: 10.3390/ijms24109058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
The mammalian formin family comprises fifteen multi-domain proteins that regulate actin dynamics and microtubules in vitro and in cells. Evolutionarily conserved formin homology (FH) 1 and 2 domains allow formins to locally modulate the cell cytoskeleton. Formins are involved in several developmental and homeostatic processes, as well as human diseases. However, functional redundancy has long hampered studies of individual formins with genetic loss-of-function approaches and prevents the rapid inhibition of formin activities in cells. The discovery of small molecule inhibitor of formin homology 2 domains (SMIFH2) in 2009 was a disruptive change that provided a powerful chemical tool to explore formins' functions across biological scales. Here, I critically discuss the characterization of SMIFH2 as a pan-formin inhibitor, as well as growing evidence of unexpected off-target effects. By collating the literature and information hidden in public repositories, outstanding controversies and fundamental open questions about the substrates and mechanism of action of SMIFH2 emerge. Whenever possible, I propose explanations for these discrepancies and roadmaps to address the paramount open questions. Furthermore, I suggest that SMIFH2 be reclassified as a multi-target inhibitor for its appealing activities on proteins involved in pathological formin-dependent processes. Notwithstanding all drawbacks and limitations, SMIFH2 will continue to prove useful in studying formins in health and disease in the years to come.
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Affiliation(s)
- Metello Innocenti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
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24
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Lampiasi N. The Migration and the Fate of Dental Pulp Stem Cells. BIOLOGY 2023; 12:biology12050742. [PMID: 37237554 DOI: 10.3390/biology12050742] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023]
Abstract
Human dental pulp stem cells (hDPSCs) are adult mesenchymal stem cells (MSCs) obtained from dental pulp and derived from the neural crest. They can differentiate into odontoblasts, osteoblasts, chondrocytes, adipocytes and nerve cells, and they play a role in tissue repair and regeneration. In fact, DPSCs, depending on the microenvironmental signals, can differentiate into odontoblasts and regenerate dentin or, when transplanted, replace/repair damaged neurons. Cell homing depends on recruitment and migration, and it is more effective and safer than cell transplantation. However, the main limitations of cell homing are the poor cell migration of MSCs and the limited information we have on the regulatory mechanism of the direct differentiation of MSCs. Different isolation methods used to recover DPSCs can yield different cell types. To date, most studies on DPSCs use the enzymatic isolation method, which prevents direct observation of cell migration. Instead, the explant method allows for the observation of single cells that can migrate at two different times and, therefore, could have different fates, for example, differentiation and self-renewal. DPSCs use mesenchymal and amoeboid migration modes with the formation of lamellipodia, filopodia and blebs, depending on the biochemical and biophysical signals of the microenvironment. Here, we present current knowledge on the possible intriguing role of cell migration, with particular attention to microenvironmental cues and mechanosensing properties, in the fate of DPSCs.
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Affiliation(s)
- Nadia Lampiasi
- Istituto per la Ricerca e l'Innovazione Biomedica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy
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25
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Hein JI, Scholz J, Körber S, Kaufmann T, Faix J. Unleashed Actin Assembly in Capping Protein-Deficient B16-F1 Cells Enables Identification of Multiple Factors Contributing to Filopodium Formation. Cells 2023; 12:cells12060890. [PMID: 36980231 PMCID: PMC10047565 DOI: 10.3390/cells12060890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023] Open
Abstract
Background: Filopodia are dynamic, finger-like actin-filament bundles that overcome membrane tension by forces generated through actin polymerization at their tips to allow extension of these structures a few microns beyond the cell periphery. Actin assembly of these protrusions is regulated by accessory proteins including heterodimeric capping protein (CP) or Ena/VASP actin polymerases to either terminate or promote filament growth. Accordingly, the depletion of CP in B16-F1 melanoma cells was previously shown to cause an explosive formation of filopodia. In Ena/VASP-deficient cells, CP depletion appeared to result in ruffling instead of inducing filopodia, implying that Ena/VASP proteins are absolutely essential for filopodia formation. However, this hypothesis was not yet experimentally confirmed. Methods: Here, we used B16-F1 cells and CRISPR/Cas9 technology to eliminate CP either alone or in combination with Ena/VASP or other factors residing at filopodia tips, followed by quantifications of filopodia length and number. Results: Unexpectedly, we find massive formations of filopodia even in the absence of CP and Ena/VASP proteins. Notably, combined inactivation of Ena/VASP, unconventional myosin-X and the formin FMNL3 was required to markedly impair filopodia formation in CP-deficient cells. Conclusions: Taken together, our results reveal that, besides Ena/VASP proteins, numerous other factors contribute to filopodia formation.
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Affiliation(s)
| | | | | | | | - Jan Faix
- Correspondence: ; Tel.: +49-511-532-2928
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26
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Sharkova M, Chow E, Erickson T, Hocking JC. The morphological and functional diversity of apical microvilli. J Anat 2023; 242:327-353. [PMID: 36281951 PMCID: PMC9919547 DOI: 10.1111/joa.13781] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/03/2022] [Accepted: 10/05/2022] [Indexed: 11/30/2022] Open
Abstract
Sensory neurons use specialized apical processes to perceive external stimuli and monitor internal body conditions. The apical apparatus can include cilia, microvilli, or both, and is adapted for the functions of the particular cell type. Photoreceptors detect light through a large, modified cilium (outer segment), that is supported by a surrounding ring of microvilli-like calyceal processes (CPs). Although first reported 150 years ago, CPs remain poorly understood. As a basis for future study, we therefore conducted a review of existing literature about sensory cell microvilli, which can act either as the primary sensory detector or as support for a cilia-based detector. While all microvilli are finger-like cellular protrusions with an actin core, the processes vary across cell types in size, number, arrangement, dynamics, and function. We summarize the current state of knowledge about CPs and the characteristics of the microvilli found on inner ear hair cells (stereocilia) and cerebral spinal fluid-contacting neurons, with comparisons to the brush border of the intestinal and renal epithelia. The structure, stability, and dynamics of the actin core are regulated by a complement of actin-binding proteins, which includes both common components and unique features when compared across cell types. Further, microvilli are often supported by lateral links, a glycocalyx, and a defined extracellular matrix, each adapted to the function and environment of the cell. Our comparison of microvillar features will inform further research into how CPs support photoreceptor function, and also provide a general basis for investigations into the structure and functions of apical microvilli found on sensory neurons.
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Affiliation(s)
- Maria Sharkova
- Department of Cell Biology, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada
| | - Erica Chow
- Department of Cell Biology, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada
| | - Timothy Erickson
- Department of BiologyUniversity of New BrunswickFrederictonNew BrunswickCanada
| | - Jennifer C. Hocking
- Department of Cell Biology, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada
- Division of Anatomy, Department of Surgery, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada
- Department of Medical Genetics, Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada
- Women and Children's Health Research InstituteUniversity of AlbertaEdmontonAlbertaCanada
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27
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Rajan S, Kudryashov DS, Reisler E. Actin Bundles Dynamics and Architecture. Biomolecules 2023; 13:450. [PMID: 36979385 PMCID: PMC10046292 DOI: 10.3390/biom13030450] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 03/04/2023] Open
Abstract
Cells use the actin cytoskeleton for many of their functions, including their division, adhesion, mechanosensing, endo- and phagocytosis, migration, and invasion. Actin bundles are the main constituent of actin-rich structures involved in these processes. An ever-increasing number of proteins that crosslink actin into bundles or regulate their morphology is being identified in cells. With recent advances in high-resolution microscopy and imaging techniques, the complex process of bundles formation and the multiple forms of physiological bundles are beginning to be better understood. Here, we review the physiochemical and biological properties of four families of highly conserved and abundant actin-bundling proteins, namely, α-actinin, fimbrin/plastin, fascin, and espin. We describe the similarities and differences between these proteins, their role in the formation of physiological actin bundles, and their properties-both related and unrelated to their bundling abilities. We also review some aspects of the general mechanism of actin bundles formation, which are known from the available information on the activity of the key actin partners involved in this process.
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Affiliation(s)
- Sudeepa Rajan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Dmitri S. Kudryashov
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH 43210, USA
| | - Emil Reisler
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
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28
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Pokrant T, Hein JI, Körber S, Disanza A, Pich A, Scita G, Rottner K, Faix J. Ena/VASP clustering at microspike tips involves lamellipodin but not I-BAR proteins, and absolutely requires unconventional myosin-X. Proc Natl Acad Sci U S A 2023; 120:e2217437120. [PMID: 36598940 PMCID: PMC9926217 DOI: 10.1073/pnas.2217437120] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/14/2022] [Indexed: 01/05/2023] Open
Abstract
Sheet-like membrane protrusions at the leading edge, termed lamellipodia, drive 2D-cell migration using active actin polymerization. Microspikes comprise actin-filament bundles embedded within lamellipodia, but the molecular mechanisms driving their formation and their potential functional relevance have remained elusive. Microspike formation requires the specific activity of clustered Ena/VASP proteins at their tips to enable processive actin assembly in the presence of capping protein, but the factors and mechanisms mediating Ena/VASP clustering are poorly understood. Systematic analyses of B16-F1 melanoma mutants lacking potential candidate proteins revealed that neither inverse BAR-domain proteins, nor lamellipodin or Abi is essential for clustering, although they differentially contribute to lamellipodial VASP accumulation. In contrast, unconventional myosin-X (MyoX) identified here as proximal to VASP was obligatory for Ena/VASP clustering and microspike formation. Interestingly, and despite the invariable distribution of other relevant marker proteins, the width of lamellipodia in MyoX-KO mutants was significantly reduced as compared with B16-F1 control, suggesting that microspikes contribute to lamellipodium stability. Consistently, MyoX removal caused marked defects in protrusion and random 2D-cell migration. Strikingly, Ena/VASP-deficiency also uncoupled MyoX cluster dynamics from actin assembly in lamellipodia, establishing their tight functional association in microspike formation.
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Affiliation(s)
- Thomas Pokrant
- Institute for Biophysical Chemistry, Hannover Medical School, 30625Hannover, Germany
| | - Jens Ingo Hein
- Institute for Biophysical Chemistry, Hannover Medical School, 30625Hannover, Germany
| | - Sarah Körber
- Institute for Biophysical Chemistry, Hannover Medical School, 30625Hannover, Germany
| | - Andrea Disanza
- IFOM ETS (Istituto Fondazione di Oncologia Molecolare ETS), - The AIRC (Italian Association for Cancer Research) Institute of Molecular Oncology, 20139Milan, Italy
| | - Andreas Pich
- Research Core Unit Proteomics, Hannover Medical School, 30625Hannover, Germany
| | - Giorgio Scita
- IFOM ETS (Istituto Fondazione di Oncologia Molecolare ETS), - The AIRC (Italian Association for Cancer Research) Institute of Molecular Oncology, 20139Milan, Italy
- Department of Oncology and Haemato-Oncology, University of Milan, 20139 Milan, Italy
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, 38106Braunschweig, Germany
- Molecular Cell Biology Group, Helmholtz Centre for Infection Research, 38124Braunschweig, Germany
| | - Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, 30625Hannover, Germany
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29
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Pokrant T, Hein JI, Körber S, Disanza A, Pich A, Scita G, Rottner K, Faix J. Ena/VASP clustering at microspike tips involves lamellipodin but not I-BAR proteins, and absolutely requires unconventional myosin-X. Proc Natl Acad Sci U S A 2023. [PMID: 36598940 DOI: 10.1101/2022.05.12.491613] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
Sheet-like membrane protrusions at the leading edge, termed lamellipodia, drive 2D-cell migration using active actin polymerization. Microspikes comprise actin-filament bundles embedded within lamellipodia, but the molecular mechanisms driving their formation and their potential functional relevance have remained elusive. Microspike formation requires the specific activity of clustered Ena/VASP proteins at their tips to enable processive actin assembly in the presence of capping protein, but the factors and mechanisms mediating Ena/VASP clustering are poorly understood. Systematic analyses of B16-F1 melanoma mutants lacking potential candidate proteins revealed that neither inverse BAR-domain proteins, nor lamellipodin or Abi is essential for clustering, although they differentially contribute to lamellipodial VASP accumulation. In contrast, unconventional myosin-X (MyoX) identified here as proximal to VASP was obligatory for Ena/VASP clustering and microspike formation. Interestingly, and despite the invariable distribution of other relevant marker proteins, the width of lamellipodia in MyoX-KO mutants was significantly reduced as compared with B16-F1 control, suggesting that microspikes contribute to lamellipodium stability. Consistently, MyoX removal caused marked defects in protrusion and random 2D-cell migration. Strikingly, Ena/VASP-deficiency also uncoupled MyoX cluster dynamics from actin assembly in lamellipodia, establishing their tight functional association in microspike formation.
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Affiliation(s)
- Thomas Pokrant
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Jens Ingo Hein
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Sarah Körber
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Andrea Disanza
- IFOM ETS (Istituto Fondazione di Oncologia Molecolare ETS), - The AIRC (Italian Association for Cancer Research) Institute of Molecular Oncology, 20139 Milan, Italy
| | - Andreas Pich
- Research Core Unit Proteomics, Hannover Medical School, 30625 Hannover, Germany
| | - Giorgio Scita
- IFOM ETS (Istituto Fondazione di Oncologia Molecolare ETS), - The AIRC (Italian Association for Cancer Research) Institute of Molecular Oncology, 20139 Milan, Italy
- Department of Oncology and Haemato-Oncology, University of Milan, 20139 Milan, Italy
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
- Molecular Cell Biology Group, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
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30
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Fitz GN, Weck ML, Bodnya C, Perkins OL, Tyska MJ. Protrusion growth driven by myosin-generated force. Dev Cell 2023; 58:18-33.e6. [PMID: 36626869 PMCID: PMC9940483 DOI: 10.1016/j.devcel.2022.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/10/2022] [Accepted: 11/29/2022] [Indexed: 01/11/2023]
Abstract
Actin-based protrusions extend from the surface of all eukaryotic cells, where they support diverse activities essential for life. Models of protrusion growth hypothesize that actin filament assembly exerts force for pushing the plasma membrane outward. However, membrane-associated myosin motors are also abundant in protrusions, although their potential for contributing, growth-promoting force remains unexplored. Using an inducible system that docks myosin motor domains to membrane-binding modules with temporal control, we found that application of myosin-generated force to the membrane is sufficient for driving robust protrusion elongation in human, mouse, and pig cell culture models. Protrusion growth scaled with motor accumulation, required barbed-end-directed force, and was independent of cargo delivery or recruitment of canonical elongation factors. Application of growth-promoting force was also supported by structurally distinct myosin motors and membrane-binding modules. Thus, myosin-generated force can drive protrusion growth, and this mechanism is likely active in diverse biological contexts.
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Affiliation(s)
- Gillian N Fitz
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Meredith L Weck
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Caroline Bodnya
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Olivia L Perkins
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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31
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Brunet T, Booth DS. Cell polarity in the protist-to-animal transition. Curr Top Dev Biol 2023; 154:1-36. [PMID: 37100515 DOI: 10.1016/bs.ctdb.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
A signature feature of the animal kingdom is the presence of epithelia: sheets of polarized cells that both insulate the organism from its environment and mediate interactions with it. Epithelial cells display a marked apico-basal polarity, which is highly conserved across the animal kingdom, both in terms of morphology and of molecular regulators. How did this architecture first evolve? Although the last eukaryotic common ancestor almost certainly possessed a simple form of apico-basal polarity (marked by the presence of one or several flagella at a single cellular pole), comparative genomics and evolutionary cell biology reveal that the polarity regulators of animal epithelial cells have a surprisingly complex and stepwise evolutionary history. Here, we retrace their evolutionary assembly. We suggest that the "polarity network" that polarized animal epithelial cells evolved by integration of initially independent cellular modules that evolved at distinct steps of our evolutionary ancestry. The first module dates back to the last common ancestor of animals and amoebozoans and involved Par1, extracellular matrix proteins, and the integrin-mediated adhesion complex. Other regulators, such as Cdc42, Dlg, Par6 and cadherins evolved in ancient unicellular opisthokonts, and might have first been involved in F-actin remodeling and filopodial dynamics. Finally, the bulk of "polarity proteins" as well as specialized adhesion complexes evolved in the metazoan stem-line, in concert with the newly evolved intercellular junctional belts. Thus, the polarized architecture of epithelia can be understood as a palimpsest of components of distinct histories and ancestral functions, which have become tightly integrated in animal tissues.
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32
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Moreland ZG, Bird JE. Myosin motors in sensory hair bundle assembly. Curr Opin Cell Biol 2022; 79:102132. [PMID: 36257241 DOI: 10.1016/j.ceb.2022.102132] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/02/2022] [Accepted: 09/07/2022] [Indexed: 01/31/2023]
Abstract
Mechanosensory hair bundles are assembled from actin-based stereocilia that project from the apical surface of hair cells in the inner ear. Stereocilia architecture is critical for the transduction of sound and accelerations, and structural defects in these mechano-sensors are a clinical cause of hearing and balance disorders in humans. Unconventional myosin motors are central to the assembly and shaping of stereocilia architecture. A sub-group of myosin motors with MyTH4-FERM domains (MYO7A, MYO15A) are particularly important in these processes, and hypothesized to act as transporters delivering structural and actin-regulatory cargos, in addition to generating force and tension. In this review, we summarize existing evidence for how MYO7A and MYO15A operate and how their dysfunction leads to stereocilia pathology. We further highlight emerging properties of the MyTH4/FERM myosin family and speculate how these new functions might contribute towards the acquisition and maintenance of mechano-sensitivity.
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Affiliation(s)
- Zane G Moreland
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA; Myology Institute, University of Florida, Gainesville, FL, 32610, USA; Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, 32610, USA
| | - Jonathan E Bird
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA; Myology Institute, University of Florida, Gainesville, FL, 32610, USA.
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33
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Clarke HJ. Transzonal projections: Essential structures mediating intercellular communication in the mammalian ovarian follicle. Mol Reprod Dev 2022; 89:509-525. [PMID: 36112806 DOI: 10.1002/mrd.23645] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/22/2022] [Accepted: 08/31/2022] [Indexed: 12/25/2022]
Abstract
The development of germ cells relies on contact and communication with neighboring somatic cells that provide metabolic support and regulatory signals. In females, contact is achieved through thin cytoplasmic processes that project from follicle cells surrounding the oocyte, extend through an extracellular matrix (ECM) that lies between them, and reach its surface. In mammals, the ECM is termed the zona pellucida and the follicular cell processes are termed transzonal projections (TZPs). TZPs become detectable when the zona pellucida is laid down during early folliculogenesis and subsequently increase in number as oocyte growth progresses. They then rapidly disappear at the time of ovulation, permanently breaking germ-soma contact. Here we review the life cycle and functions of the TZPs. We begin with an overview of the morphology and cytoskeletal structure of TZPs, in the context of actin- and tubulin-based cytoplasmic processes in other cell types. Next, we review the roles played by TZPs in mediating progression through successive stages of oocyte development. We then discuss two mechanisms that may generate TZPs-stretching at pre-existing points of granulosa cell-oocyte contact and elaboration of new processes that push through the zona pellucida-as well as gene products implicated in their formation or function. Finally, we describe the signaling pathways that cause TZPs to be retracted in response to signals that also trigger meiotic maturation and ovulation of the oocyte. The principles and mechanisms that govern TZP behavior may be relevant to understanding communication between physically separated cells in other physiological contexts.
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Affiliation(s)
- Hugh J Clarke
- Program in Child Health and Human Development, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
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34
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Dooley SA, Engevik KA, Digrazia J, Stubler R, Kaji I, Krystofiak E, Engevik AC. Myosin 5b is required for proper localization of the intermicrovillar adhesion complex in the intestinal brush border. Am J Physiol Gastrointest Liver Physiol 2022; 323:G501-G510. [PMID: 36218265 PMCID: PMC9639760 DOI: 10.1152/ajpgi.00212.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 01/31/2023]
Abstract
Intestinal enterocytes have an elaborate apical membrane of actin-rich protrusions known as microvilli. The organization of microvilli is orchestrated by the intermicrovillar adhesion complex (IMAC), which connects the distal tips of adjacent microvilli. The IMAC is composed of CDHR2 and CDHR5 as well as the scaffolding proteins USH1C, ANKS4B, and Myosin 7b (MYO7B). To create an IMAC, cells must transport the proteins to the apical membrane. Myosin 5b (MYO5B) is a molecular motor that traffics ion transporters to the apical membrane of enterocytes, and we hypothesized that MYO5B may also be responsible for the localization of IMAC proteins. To address this question, we used two different mouse models: 1) neonatal germline MYO5B knockout (MYO5B KO) mice and 2) adult intestinal-specific tamoxifen-inducible VillinCreERT2;MYO5Bflox/flox mice. In control mice, immunostaining revealed that CDHR2, CDHR5, USH1C, and MYO7B were highly enriched at the tips of the microvilli. In contrast, neonatal germline and adult MYO5B-deficient mice showed loss of apical CDHR2, CDHR5, and MYO7B in the brush border and accumulation in a subapical compartment. Colocalization analysis revealed decreased Mander's coefficients in adult inducible MYO5B-deficient mice compared with control mice for CDHR2, CDHR5, USH1C, and MYO7B. Scanning electron microscopy images further demonstrated aberrant microvilli packing in adult inducible MYO5B-deficient mouse small intestine. These data indicate that MYO5B is responsible for the delivery of IMAC components to the apical membrane.NEW & NOTEWORTHY The intestinal epithelium absorbs nutrients and water through an elaborate apical membrane of highly organized microvilli. Microvilli organization is regulated by the intermicrovillar adhesion complexes, which create links between neighboring microvilli and control microvilli packing and density. In this study, we report a new trafficking partner of the IMAC, Myosin 5b. Loss of Myosin 5b results in a disorganized brush border and failure of IMAC proteins to reach the distal tips of microvilli.
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Affiliation(s)
- Sarah A Dooley
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Kristen A Engevik
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas
| | - Jessica Digrazia
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Rachel Stubler
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Evan Krystofiak
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee
- Cell Imaging Shared Resource, Vanderbilt University, Nashville, Tennessee
| | - Amy C Engevik
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
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35
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Jeng JY, Carlton AJ, Goodyear RJ, Chinowsky C, Ceriani F, Johnson SL, Sung TC, Dayn Y, Richardson GP, Bowl MR, Brown SD, Manor U, Marcotti W. AAV-mediated rescue of Eps8 expression in vivo restores hair-cell function in a mouse model of recessive deafness. Mol Ther Methods Clin Dev 2022; 26:355-370. [PMID: 36034774 PMCID: PMC9382420 DOI: 10.1016/j.omtm.2022.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/15/2022] [Indexed: 11/24/2022]
Abstract
The transduction of acoustic information by hair cells depends upon mechanosensitive stereociliary bundles that project from their apical surface. Mutations or absence of the stereociliary protein EPS8 cause deafness in humans and mice, respectively. Eps8 knockout mice (Eps8 -/- ) have hair cells with immature stereocilia and fail to become sensory receptors. Here, we show that exogenous delivery of Eps8 using Anc80L65 in P1-P2 Eps8 -/- mice in vivo rescued the hair bundle structure of apical-coil hair cells. Rescued hair bundles correctly localize EPS8, WHIRLIN, MYO15, and BAIAP2L2, and generate normal mechanoelectrical transducer currents. Inner hair cells with normal-looking stereocilia re-expressed adult-like basolateral ion channels (BK and KCNQ4) and have normal exocytosis. The number of hair cells undergoing full recovery was not sufficient to rescue hearing in Eps8 -/- mice. Adeno-associated virus (AAV)-transduction of P3 apical-coil and P1-P2 basal-coil hair cells does not rescue hair cells, nor does Anc80L65-Eps8 delivery in adult Eps8 -/- mice. We propose that AAV-induced gene-base therapy is an efficient strategy to recover the complex hair-cell defects in Eps8 -/- mice. However, this therapeutic approach may need to be performed in utero since, at postnatal ages, Eps8 -/- hair cells appear to have matured or accumulated damage beyond the point of repair.
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Affiliation(s)
- Jing-Yi Jeng
- School of Bioscience, University of Sheffield, Sheffield S10 2TN, UK
| | - Adam J. Carlton
- School of Bioscience, University of Sheffield, Sheffield S10 2TN, UK
| | - Richard J. Goodyear
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Colbie Chinowsky
- Waitt Advanced Biophotonics Center, Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Federico Ceriani
- School of Bioscience, University of Sheffield, Sheffield S10 2TN, UK
| | - Stuart L. Johnson
- School of Bioscience, University of Sheffield, Sheffield S10 2TN, UK
- Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
| | - Tsung-Chang Sung
- Transgenic Core, Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Yelena Dayn
- Transgenic Core, Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Guy P. Richardson
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Michael R. Bowl
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD UK
| | - Steve D.M. Brown
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD UK
| | - Uri Manor
- Waitt Advanced Biophotonics Center, Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Walter Marcotti
- School of Bioscience, University of Sheffield, Sheffield S10 2TN, UK
- Neuroscience Institute, University of Sheffield, Sheffield S10 2TN, UK
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36
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Engevik MA, Engevik AC. Myosins and membrane trafficking in intestinal brush border assembly. Curr Opin Cell Biol 2022; 77:102117. [PMID: 35870341 DOI: 10.1016/j.ceb.2022.102117] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 06/15/2022] [Accepted: 06/23/2022] [Indexed: 11/29/2022]
Abstract
Myosins are a class of motors that participate in a wide variety of cellular functions including organelle transport, cell adhesion, endocytosis and exocytosis, movement of RNA, and cell motility. Among the emerging roles for myosins is regulation of the assembly, morphology, and function of actin protrusions such as microvilli. The intestine harbors an elaborate apical membrane composed of highly organized microvilli. Microvilli assembly and function are intricately tied to several myosins including Myosin 1a, non-muscle Myosin 2c, Myosin 5b, Myosin 6, and Myosin 7b. Here, we review the research progress made in our understanding of myosin mediated apical assembly.
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Affiliation(s)
- Melinda A Engevik
- Department of Regenerative Medicine & Cell Biology, Medical University of South Carolina
| | - Amy C Engevik
- Department of Regenerative Medicine & Cell Biology, Medical University of South Carolina.
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37
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Yan W, Chen G, Li J. Structure of the Harmonin PDZ2 and coiled-coil domains in a complex with CDHR2 tail and its implications. FASEB J 2022; 36:e22425. [PMID: 35747925 DOI: 10.1096/fj.202200403rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/05/2022] [Accepted: 06/09/2022] [Indexed: 11/11/2022]
Abstract
Harmonin is a protein containing multiple PDZ domains and is required for the development and maintenance of hair cell stereocilia and brush border microvilli. Mutations in the USH1C gene can cause Usher syndrome type 1C, a severe inheritable disease characterized by the loss of hearing and vision. Here, by solving the high-resolution crystal structure of Harmonin PDZ2 and coiled-coil domains in a complex with the tail of cadherin-related family member 2, we demonstrated that mutations located in the Harmonin PDZ2 domain and found in patients could affect its stability, and thus, the target binding capability. The structure also implies that the coiled-coil domain could form antiparallel dimers under high concentrations, possibly when Harmonin underwent liquid-liquid phase separation in the upper tip-link density in hair cell stereocilia or microvilli of enterocytes of the intestinal epithelium. The crystal structure, together with the biochemical analysis, provided mechanistic implications for Harmonin mutations causing Usher syndrome, non-syndromic deafness, or enteropathy.
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Affiliation(s)
- Wenxia Yan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Guanhao Chen
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou, China
| | - Jianchao Li
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou, China.,Department of Otorhinolaryngology, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, China
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38
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Synergistic antibacterial effects of low-intensity ultrasound and peptide LCMHC against Staphylococcus aureus. Int J Food Microbiol 2022; 373:109713. [DOI: 10.1016/j.ijfoodmicro.2022.109713] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 04/28/2022] [Accepted: 05/05/2022] [Indexed: 11/20/2022]
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39
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Granados-Aparici S, Volodarsky-Perel A, Yang Q, Anam S, Tulandi T, Buckett W, Son WY, Younes G, Chung JT, Jin S, Terret MÉ, Clarke HJ. MYO10 promotes transzonal projection (TZP)-dependent germ line-somatic contact during mammalian folliculogenesis. Biol Reprod 2022; 107:474-487. [PMID: 35470858 PMCID: PMC9382396 DOI: 10.1093/biolre/ioac078] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/17/2022] [Accepted: 04/15/2022] [Indexed: 11/12/2022] Open
Abstract
Granulosa cells of growing ovarian follicles elaborate filopodia-like structures termed transzonal projections (TZPs) that supply the enclosed oocyte with factors essential for its development. Little is known, however, of the mechanisms underlying the generation of TZPs. We show in mouse and human that filopodia, defined by an actin backbone, emerge from granulosa cells in early-stage primary follicles and that actin-rich TZPs become detectable as soon as a space corresponding to the zona pellucida appears. mRNA encoding Myosin10 (MYO10), a motor protein that accumulates at the base and tips of filopodia and has been implicated in their initiation and elongation, is present in granulosa cells and oocytes of growing follicles. MYO10 protein accumulates in foci located mainly between the oocyte and innermost layer of granulosa cells, where it co-localizes with actin. In both mouse and human, the number of MYO10 foci increases as oocytes grow, corresponding to the increase in the number of actin-TZPs. RNAi-mediated depletion of MYO10 in cultured mouse granulosa cell-oocyte complexes is associated with a 52% reduction in the number of MYO10 foci and a 28% reduction in the number of actin-TZPs. Moreover, incubation of cumulus-oocyte complexes in the presence of epidermal growth factor, which triggers a 93% reduction in the number of actin-TZPs, is associated with a 55% reduction in the number of MYO10 foci. These results suggest that granulosa cells possess an ability to elaborate filopodia, which when directed towards the oocyte become actin-TZPs, and that MYO10 increases the efficiency of formation or maintenance of actin-TZPs.
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Affiliation(s)
- Sofia Granados-Aparici
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Alexander Volodarsky-Perel
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Qin Yang
- Research Institute of the McGill University Health Center, Montreal, Canada
| | - Sibat Anam
- Division of Experimental Medicine, McGill University, Montreal, Canada
| | - Togas Tulandi
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - William Buckett
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Weon-Young Son
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | - Grace Younes
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada
| | - Jin-Tae Chung
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | - Shaoguang Jin
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | | | - Hugh J Clarke
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.,Research Institute of the McGill University Health Center, Montreal, Canada.,Division of Experimental Medicine, McGill University, Montreal, Canada
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40
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Filopodia rotate and coil by actively generating twist in their actin shaft. Nat Commun 2022; 13:1636. [PMID: 35347113 PMCID: PMC8960877 DOI: 10.1038/s41467-022-28961-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/10/2022] [Indexed: 12/19/2022] Open
Abstract
Filopodia are actin-rich structures, present on the surface of eukaryotic cells. These structures play a pivotal role by allowing cells to explore their environment, generate mechanical forces or perform chemical signaling. Their complex dynamics includes buckling, pulling, length and shape changes. We show that filopodia additionally explore their 3D extracellular space by combining growth and shrinking with axial twisting and buckling. Importantly, the actin core inside filopodia performs a twisting or spinning motion which is observed for a range of cell types spanning from earliest development to highly differentiated tissue cells. Non-equilibrium physical modeling of actin and myosin confirm that twist is an emergent phenomenon of active filaments confined in a narrow channel which is supported by measured traction forces and helical buckles that can be ascribed to accumulation of sufficient twist. These results lead us to conclude that activity induced twisting of the actin shaft is a general mechanism underlying fundamental functions of filopodia. The authors show how tubular surface structures in all cell types, have the ability to twist and perform rotary sweeping motion to explore the extracellular environment. This has implications for migration, sensing and cell communication.
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41
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Manrique-Moreno M, Santa-González G, Gallego V. Bioactive cationic peptides as potential agents for breast cancer treatment. Biosci Rep 2021; 41:BSR20211218C. [PMID: 34874400 PMCID: PMC8655503 DOI: 10.1042/bsr20211218c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/25/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022] Open
Abstract
Breast cancer continues to affect millions of women worldwide, and the number of new cases dramatically increases every year. The physiological causes behind the disease are still not fully understood. One in every 100 cases can occur in men, and although the frequency is lower than among women, men tend to have a worse prognosis of the disease. Various therapeutic alternatives to combat the disease are available. These depend on the type and progress of the disease, and include chemotherapy, radiotherapy, surgery, and cancer immunotherapy. However, there are several well-reported side effects of these treatments that have a significant impact on life quality, and patients either relapse or are refractory to treatment. This makes it necessary to develop new therapeutic strategies. One promising initiative are bioactive peptides, which have emerged in recent years as a family of compounds with an enormous number of clinical applications due to their broad spectrum of activity. They are widely distributed in several organisms as part of their immune system. The antitumoral activity of these peptides lies in a nonspecific mechanism of action associated with their interaction with cancer cell membranes, inducing, through several routes, bilayer destabilization and cell death. This review provides an overview of the literature on the evaluation of cationic peptides as potential agents against breast cancer under different study phases. First, physicochemical characteristics such as the primary structure and charge are presented. Secondly, information about dosage, the experimental model used, and the mechanism of action proposed for the peptides are discussed.
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Affiliation(s)
- Marcela Manrique-Moreno
- Chemistry Institute, Faculty of Exact and Natural Sciences, University of Antioquia, A.A. 1226, Medellin, Antioquia
| | - Gloria A. Santa-González
- Biomedical Innovation and Research Group, Faculty of Applied and Exact Sciences, Instituto Tecnólogico Metropolitano, A.A. 54959, Medellin, Colombia
| | - Vanessa Gallego
- Chemistry Institute, Faculty of Exact and Natural Sciences, University of Antioquia, A.A. 1226, Medellin, Antioquia
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42
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Bidaud-Meynard A, Demouchy F, Nicolle O, Pacquelet A, Suman SK, Plancke CN, Robin FB, Michaux G. High-resolution dynamic mapping of the C. elegans intestinal brush border. Development 2021; 148:dev200029. [PMID: 34704594 PMCID: PMC10659032 DOI: 10.1242/dev.200029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/04/2021] [Indexed: 11/20/2022]
Abstract
The intestinal brush border is made of an array of microvilli that increases the membrane surface area for nutrient processing, absorption and host defense. Studies on mammalian cultured epithelial cells have uncovered some of the molecular players and physical constraints required to establish this apical specialized membrane. However, the building and maintenance of a brush border in vivo has not yet been investigated in detail. Here, we combined super-resolution imaging, transmission electron microscopy and genome editing in the developing nematode Caenorhabditis elegans to build a high-resolution and dynamic localization map of known and new brush border markers. Notably, we show that microvilli components are dynamically enriched at the apical membrane during microvilli outgrowth and maturation, but become highly stable once microvilli are built. This new toolbox will be instrumental for understanding the molecular processes of microvilli growth and maintenance in vivo, as well as the effect of genetic perturbations, notably in the context of disorders affecting brush border integrity.
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Affiliation(s)
- Aurélien Bidaud-Meynard
- Université de Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Flora Demouchy
- Université de Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Ophélie Nicolle
- Université de Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Anne Pacquelet
- Université de Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Shashi Kumar Suman
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Camille N Plancke
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - François B Robin
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Grégoire Michaux
- Université de Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
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43
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Matoo S, Graves MJ, Acharya P, Choi MS, Storad ZA, Idris RAES, Pickles BK, Arvay TO, Shinder PE, Gerts A, Papish JP, Crawley SW. Comparative analysis of the MyTH4-FERM myosins reveals insights into the determinants of actin track selection in polarized epithelia. Mol Biol Cell 2021; 32:ar30. [PMID: 34473561 PMCID: PMC8693963 DOI: 10.1091/mbc.e20-07-0494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
MyTH4-FERM (MF) myosins evolved to play a role in the creation and function of a variety of actin-based membrane protrusions that extend from cells. Here we performed an analysis of the MF myosins, Myo7A, Myo7B, and Myo10, to gain insight into how they select for their preferred actin networks. Using enterocytes that create spatially separated actin tracks in the form of apical microvilli and basal filopodia, we show that actin track selection is principally guided by the mode of oligomerization of the myosin along with the identity of the motor domain, with little influence from the specific composition of the lever arm. Chimeric variants of Myo7A and Myo7B fused to a leucine zipper parallel dimerization sequence in place of their native tails both selected apical microvilli as their tracks, while a truncated Myo10 used its native antiparallel coiled-coil to traffic to the tips of filopodia. Swapping lever arms between the Class 7 and 10 myosins did not change actin track preference. Surprisingly, fusing the motor-neck region of Myo10 to a leucine zipper or oligomerization sequences derived from the Myo7A and Myo7B cargo proteins USH1G and ANKS4B, respectively, re-encoded the actin track usage of Myo10 to apical microvilli with significant efficiency.
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Affiliation(s)
- Samaneh Matoo
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Maura J Graves
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Prashun Acharya
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Myoung Soo Choi
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Zachary A Storad
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | | | - Brooke K Pickles
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Taylen O Arvay
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Paula E Shinder
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Andrew Gerts
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Jacob P Papish
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
| | - Scott W Crawley
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606
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44
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Abstract
Robert Insall introduces the cytoskeleton special issue and summarises some recent changes in our view of actin function and regulation.
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Affiliation(s)
- Robert Insall
- Institute of Cancer Sciences, University of Glasgow, Garscube Campus, Switchback Road, Bearsden, Glasgow G61 1QH, UK; Cancer Research UK Beatson Institute, Switchback Road, Bearsden, Glasgow G61 1BD, UK.
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