1
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Felipe-López A, Hansmeier N, Hensel M. Destruction of the brush border by Salmonella enterica sv. Typhimurium subverts resorption by polarized epithelial cells. Front Microbiol 2024; 15:1329798. [PMID: 38894970 PMCID: PMC11183102 DOI: 10.3389/fmicb.2024.1329798] [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: 10/29/2023] [Accepted: 05/06/2024] [Indexed: 06/21/2024] Open
Abstract
Salmonella enterica serovar Typhimurium is an invasive, facultative intracellular gastrointestinal pathogen that destroys the brush border of polarized epithelial cells (PEC). The brush border is critical for the functions of PEC because it resorbs nutrients from the intestinal lumen and builds a physical barrier to infecting pathogens. The manipuation of PEC during infection by Salmonella was investigated by live-cell imaging and ultrastructural analysed of the brush border. We demonstrate that the destruction of the brush border by Salmonella significantly reduces the resorption surface of PEC along with the abrogation of endocytosis at the apical side of PEC. Both these changes in the physiology of PEC were associated with the translocation of type III secretion system effector protein SopE. Additionally, the F-actin polymerization rate at the apical side of PEC was highly altered by SopE, indicating that reduced endocytosis observed in infected PEC is related to the manipulation of F-actin polymerization mediated by SopE and, to a lesser extent, by effectors SopE2 or SipA. We further observed that in the absence of SopE, Salmonella effaced microvilli and induced reticular F-actin by bacterial accumulation during prolonged infection periods. In contrast to strains translocating SopE, strains lacking SopE did not alter resorption by PEC. Finally, we observed that after engulfment of Salmonella, ezrin was lost from the apical side of PEC and found later in early endosomes containing Salmonella. Our observations suggest that the destruction of the brush border by Salmonella may contribute to the pathogenesis of diarrhea.
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Affiliation(s)
| | | | - Michael Hensel
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- CellNanOs—Center of Cellular Nanoanalytics Osnabrück, Universität Osnabrück, Osnabrück, Germany
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2
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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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3
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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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4
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Dixson AC, Dawson TR, Di Vizio D, Weaver AM. Context-specific regulation of extracellular vesicle biogenesis and cargo selection. Nat Rev Mol Cell Biol 2023; 24:454-476. [PMID: 36765164 PMCID: PMC10330318 DOI: 10.1038/s41580-023-00576-0] [Citation(s) in RCA: 147] [Impact Index Per Article: 147.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2023] [Indexed: 02/12/2023]
Abstract
To coordinate, adapt and respond to biological signals, cells convey specific messages to other cells. An important aspect of cell-cell communication involves secretion of molecules into the extracellular space. How these molecules are selected for secretion has been a fundamental question in the membrane trafficking field for decades. Recently, extracellular vesicles (EVs) have been recognized as key players in intercellular communication, carrying not only membrane proteins and lipids but also RNAs, cytosolic proteins and other signalling molecules to recipient cells. To communicate the right message, it is essential to sort cargoes into EVs in a regulated and context-specific manner. In recent years, a wealth of lipidomic, proteomic and RNA sequencing studies have revealed that EV cargo composition differs depending upon the donor cell type, metabolic cues and disease states. Analyses of distinct cargo 'fingerprints' have uncovered mechanistic linkages between the activation of specific molecular pathways and cargo sorting. In addition, cell biology studies are beginning to reveal novel biogenesis mechanisms regulated by cellular context. Here, we review context-specific mechanisms of EV biogenesis and cargo sorting, focusing on how cell signalling and cell state influence which cellular components are ultimately targeted to EVs.
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Affiliation(s)
- Andrew C Dixson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - T Renee Dawson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
- Center for Extracellular Vesicle Research, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Dolores Di Vizio
- Department of Surgery, Division of Cancer Biology and Therapeutics, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alissa M Weaver
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Center for Extracellular Vesicle Research, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.
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5
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Su P, Wu Y, Xie F, Zheng Q, Chen L, Liu Z, Meng X, Zhou F, Zhang L. A Review of Extracellular Vesicles in COVID-19 Diagnosis, Treatment, and Prevention. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023:e2206095. [PMID: 37144543 DOI: 10.1002/advs.202206095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 04/15/2023] [Indexed: 05/06/2023]
Abstract
The 2019 novel coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is ongoing, and has necessitated scientific efforts in disease diagnosis, treatment, and prevention. Interestingly, extracellular vesicles (EVs) have been crucial in these developments. EVs are a collection of various nanovesicles which are delimited by a lipid bilayer. They are enriched in proteins, nucleic acids, lipids, and metabolites, and naturally released from different cells. Their natural material transport properties, inherent long-term recycling ability, excellent biocompatibility, editable targeting, and inheritance of parental cell properties make EVs one of the most promising next-generation drug delivery nanocarriers and active biologics. During the COVID-19 pandemic, many efforts have been made to exploit the payload of natural EVs for the treatment of COVID-19. Furthermore, strategies that use engineered EVs to manufacture vaccines and neutralization traps have produced excellent efficacy in animal experiments and clinical trials. Here, the recent literature on the application of EVs in COVID-19 diagnosis, treatment, damage repair, and prevention is reviewed. And the therapeutic value, application strategies, safety, and biotoxicity in the production and clinical applications of EV agents for COVID-19 treatment, as well as inspiration for using EVs to block and eliminate novel viruses are discussed.
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Affiliation(s)
- Peng Su
- Department of Breast Surgery, Zhejiang Provincial People's Hospital, Hangzhou, 310014, P. R. China
- Institutes of Biology and Medical Science, Soochow University, Suzhou, 215123, P. R. China
| | - Yuchen Wu
- Department of Clinical Medicine, The First School of Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, P. R. China
| | - Feng Xie
- Institutes of Biology and Medical Science, Soochow University, Suzhou, 215123, P. R. China
| | - Qinghui Zheng
- Department of Breast Surgery, Zhejiang Provincial People's Hospital, Hangzhou, 310014, P. R. China
| | - Long Chen
- Center for Translational Medicine, The Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang, Jiangsu, 215600, China
| | - Zhuang Liu
- Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Xuli Meng
- Department of Breast Surgery, Zhejiang Provincial People's Hospital, Hangzhou, 310014, P. R. China
| | - Fangfang Zhou
- Institutes of Biology and Medical Science, Soochow University, Suzhou, 215123, P. R. China
| | - Long Zhang
- Department of Breast Surgery, Zhejiang Provincial People's Hospital, Hangzhou, 310014, P. R. China
- MOE Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, 310058, P. R. China
- Cancer Center, Zhejiang University, Hangzhou, Zhejiang, 310058, P. R. China
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6
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Jing H, Wu X, Xiang M, Wang C, Novakovic VA, Shi J. Microparticle Phosphatidylserine Mediates Coagulation: Involvement in Tumor Progression and Metastasis. Cancers (Basel) 2023; 15:cancers15071957. [PMID: 37046617 PMCID: PMC10093313 DOI: 10.3390/cancers15071957] [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: 01/31/2023] [Revised: 03/17/2023] [Accepted: 03/17/2023] [Indexed: 04/14/2023] Open
Abstract
Tumor progression and cancer metastasis has been linked to the release of microparticles (MPs), which are shed upon cell activation or apoptosis and display parental cell antigens, phospholipids such as phosphatidylserine (PS), and nucleic acids on their external surfaces. In this review, we highlight the biogenesis of MPs as well as the pathophysiological processes of PS externalization and its involvement in coagulation activation. We review the available evidence, suggesting that coagulation factors (mainly tissue factor, thrombin, and fibrin) assist in multiple steps of tumor dissemination, including epithelial-mesenchymal transition, extracellular matrix remodeling, immune escape, and tumor angiogenesis to support the formation of the pre-metastatic niche. Platelets are not just bystander cells in circulation but are functional players in primary tumor growth and metastasis. Tumor-induced platelet aggregation protects circulating tumor cells (CTCs) from the blood flow shear forces and immune cell attack while also promoting the binding of CTCs to endothelial cells and extravasation, which activates tumor invasion and sustains metastasis. Finally, in terms of therapy, lactadherin can inhibit coagulation by competing effectively with coagulation factors for PS binding sites and may similarly delay tumor progression. Furthermore, we also investigate the therapeutic potential of coagulation factor inhibitors within the context of cancer treatment. The development of multiple therapies targeting platelet activation and platelet-tumor cell interactions may not only reduce the lethal consequences of thrombosis but also impede tumor growth and spread.
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Affiliation(s)
- Haijiao Jing
- Department of Hematology, The First Hospital, Harbin Medical University, Harbin 150001, China
| | - Xiaoming Wu
- Department of Hematology, The First Hospital, Harbin Medical University, Harbin 150001, China
| | - Mengqi Xiang
- Department of Hematology, The First Hospital, Harbin Medical University, Harbin 150001, China
| | - Chengyue Wang
- Department of Hematology, The First Hospital, Harbin Medical University, Harbin 150001, China
| | - Valerie A Novakovic
- Department of Research, VA Boston Healthcare System, Harvard Medical School, Boston, MA 02132, USA
| | - Jialan Shi
- Department of Hematology, The First Hospital, Harbin Medical University, Harbin 150001, China
- Department of Research, VA Boston Healthcare System, Harvard Medical School, Boston, MA 02132, USA
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02132, USA
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7
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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: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [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 Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Erica Chow
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Timothy Erickson
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada
| | - Jennifer C Hocking
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Division of Anatomy, Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
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8
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Felipe-López A, Hansmeier N, Danzer C, Hensel M. Manipulation of microvillar proteins during Salmonella enterica invasion results in brush border effacement and actin remodeling. Front Cell Infect Microbiol 2023; 13:1137062. [PMID: 36936760 PMCID: PMC10018140 DOI: 10.3389/fcimb.2023.1137062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/10/2023] [Indexed: 03/06/2023] Open
Abstract
Enterocyte invasion by the gastrointestinal pathogen Salmonella enterica is accompanied by loss of brush border and massive remodeling of the actin cytoskeleton, leading to microvilli effacement and formation of membrane ruffles. These manipulations are mediated by effector proteins translocated by the Salmonella Pathogenicity Island 1-encoded type III secretion system (SPI1-T3SS). To unravel the mechanisms of microvilli effacement and contribution of SPI1-T3SS effector proteins, the dynamics of host-pathogen interactions was analyzed using live cell imaging (LCI) of polarized epithelial cells (PEC) expressing LifeAct-GFP. PEC were infected with S. enterica wild-type and mutant strains with defined defects in SPI1-T3SS effector proteins, and pharmacological inhibition of actin assembly were applied. We identified that microvilli effacement involves two distinct mechanisms: i) F-actin depolymerization mediated by villin and ii), the consumption of cytoplasmic G-actin by formation of membrane ruffles. By analyzing the contribution of individual SPI1-T3SS effector proteins, we demonstrate that SopE dominantly triggers microvilli effacement and formation of membrane ruffles. Furthermore, SopE via Rac1 indirectly manipulates villin, which culminates in F-actin depolymerization. Collectively, these results indicate that SopE has dual functions during F-actin remodeling in PEC. While SopE-Rac1 triggers F-actin polymerization and ruffle formation, activation of PLCγ and villin by SopE depolymerizes F-actin in PEC. These results demonstrate the key role of SopE in destruction of the intestinal barrier during intestinal infection by Salmonella.
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Affiliation(s)
| | | | - Claudia Danzer
- Mikrobiologisches Institut, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Michael Hensel
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- *Correspondence: Michael Hensel,
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9
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Diaz-Valencia JD, Estrada-Abreo LA, Rodríguez-Cruz L, Salgado-Aguayo AR, Patiño-López G. Class I Myosins, molecular motors involved in cell migration and cancer. Cell Adh Migr 2022; 16:1-12. [PMID: 34974807 PMCID: PMC8741282 DOI: 10.1080/19336918.2021.2020705] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/02/2021] [Accepted: 12/16/2021] [Indexed: 01/13/2023] Open
Abstract
Class I Myosins are a subfamily of motor proteins with ATPase activity and a characteristic structure conserved in all myosins: A N-Terminal Motor Domain, a central Neck and a C terminal Tail domain. Humans have eight genes for these myosins. Class I Myosins have different functions: regulate membrane tension, participate in endocytosis, exocytosis, intracellular trafficking and cell migration. Cell migration is influenced by many cellular components including motor proteins, like myosins. Recently has been reported that changes in myosin expression have an impact on the migration of cancer cells, the formation of infiltrates and metastasis. We propose that class I myosins might be potential markers for future diagnostic, prognostic or even as therapeutic targets in leukemia and other cancers.Abbreviations: Myo1g: Myosin 1g; ALL: Acute Lymphoblastic Leukemia, TH1: Tail Homology 1; TH2: Tail Homology 2; TH3: Tail Homology 3.
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Affiliation(s)
- Juan D. Diaz-Valencia
- Immunology and Proteomics Laboratory, Children’s Hospital of Mexico, Mexico City, Mexico
| | - Laura A. Estrada-Abreo
- Immunology and Proteomics Laboratory, Children’s Hospital of Mexico, Mexico City, Mexico
- Cell Biology and Flow Cytometry Laboratory, Metropolitan Autonomous University, México City, Mexico
| | - Leonor Rodríguez-Cruz
- Cell Biology and Flow Cytometry Laboratory, Metropolitan Autonomous University, México City, Mexico
| | - Alfonso R. Salgado-Aguayo
- Rheumatic Diseases Laboratory, National Institute of Respiratory Diseases “Ismael Cosío Villegas”, Mexico City, Mexico
| | - Genaro Patiño-López
- Immunology and Proteomics Laboratory, Children’s Hospital of Mexico, Mexico City, Mexico
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10
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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: 0] [Impact Index Per Article: 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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11
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Ali Q, Ma S, La S, Guo Z, Liu B, Gao Z, Farooq U, Wang Z, Zhu X, Cui Y, Li D, Shi Y. Microbial short-chain fatty acids: a bridge between dietary fibers and poultry gut health. Anim Biosci 2022; 35:1461-1478. [PMID: 35507857 PMCID: PMC9449382 DOI: 10.5713/ab.21.0562] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 03/18/2022] [Indexed: 11/27/2022] Open
Abstract
The maintenance of poultry gut health is complex depending on the intricate balance among diet, the commensal microbiota, and the mucosa, including the gut epithelium and the superimposing mucus layer. Changes in microflora composition and abundance can confer beneficial or detrimental effects on fowl. Antibiotics have devastating impacts on altering the landscape of gut microbiota, which further leads to antibiotic resistance or spread the pathogenic populations. By eliciting the landscape of gut microbiota, strategies should be made to break down the regulatory signals of pathogenic bacteria. The optional strategy of conferring dietary fibers (DFs) can be used to counterbalance the gut microbiota. DFs are the non-starch carbohydrates indigestible by host endogenous enzymes but can be fermented by symbiotic microbiota to produce short-chain fatty acids (SCFAs). This is one of the primary modes through which the gut microbiota interacts and communicate with the host. The majority of SCFAs are produced in the large intestine (particularly in the caecum), where they are taken up by the enterocytes or transported through portal vein circulation into the bloodstream. Recent shreds of evidence have elucidated that SCFAs affect the gut and modulate the tissues and organs either by activating G-protein-coupled receptors or affecting epigenetic modifications in the genome through inducing histone acetylase activities and inhibiting histone deacetylases. Thus, in this way, SCFAs vastly influence poultry health by promoting energy regulation, mucosal integrity, immune homeostasis, and immune maturation. In this review article, we will focus on DFs, which directly interact with gut microbes and lead to the production of SCFAs. Further, we will discuss the current molecular mechanisms of how SCFAs are generated, transported, and modulated the pro-and anti-inflammatory immune responses against pathogens and host physiology and gut health.
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12
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Hu Y, Sun Y, Wan C, Dai X, Wu S, Lo PC, Huang J, Lovell JF, Jin H, Yang K. Microparticles: biogenesis, characteristics and intervention therapy for cancers in preclinical and clinical research. J Nanobiotechnology 2022; 20:189. [PMID: 35418077 PMCID: PMC9006557 DOI: 10.1186/s12951-022-01358-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 03/08/2022] [Indexed: 12/24/2022] Open
Abstract
Extracellular vesicles (EVs), spherical biological vesicles, mainly contain nucleic acids, proteins, lipids and metabolites for biological information transfer between cells. Microparticles (MPs), a subtype of EVs, directly emerge from plasma membranes, and have gained interest in recent years. Specific cell stimulation conditions, such as ultraviolet and X-rays irradiation, can induce the release of MPs, which are endowed with unique antitumor functionalities, either for therapeutic vaccines or as direct antitumor agents. Moreover, the size of MPs (100–1000 nm) and their spherical structures surrounded by a lipid bilayer membrane allow MPs to function as delivery vectors for bioactive antitumor compounds, with favorable phamacokinetic behavior, immunostimulatory activity and biological function, without inherent carrier-specific toxic side effects. In this review, the mechanisms underlying MP biogenesis, factors that influence MP production, properties of MP membranes, size, composition and isolation methods of MPs are discussed. Additionally, the applications and mechanisms of action of MPs, as well as the main hurdles for their applications in cancer management, are introduced.
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Affiliation(s)
- Yan Hu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Yajie Sun
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Chao Wan
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xiaomeng Dai
- Department of Medical Oncology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Shuhui Wu
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Pui-Chi Lo
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong kong, China
| | - Jing Huang
- College of Biomedicine and Health and College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Honglin Jin
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. .,College of Biomedicine and Health and College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Kunyu Yang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
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13
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Cajulao JM, Chen L. Lactobacillus rhamnosus reduces the cytotoxic effects of group B streptococcus on HeLa cells. Microb Pathog 2021; 161:105271. [PMID: 34728370 DOI: 10.1016/j.micpath.2021.105271] [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: 06/24/2021] [Revised: 09/18/2021] [Accepted: 10/23/2021] [Indexed: 10/19/2022]
Abstract
Group B Streptococcus (GBS) is an opportunistic pathogen found in the vaginal tract and is a leading cause of preterm birth and neonatal illness. Aside from GBS, the vaginal tract is predominantly colonized by commensal Lactobacillus species that are thought to protect the vaginal tract from pathogens, including GBS. Studies that examined if, and how Lactobacilli modulate GBS pathogenicity remain limited. This study sought to investigate the potential protective role of Lactobacillus rhamnosus against GBS, using an in vitro model system. Immunofluorescence microscopy and Scanning Electron Microscopy (SEM) captured images of infected HeLa cells and were analyzed using the image analysis program ImageJ. Results indicate that GBS causes HeLa cell detachment unless L. rhamnosus is present. SEM images show that GBS reduces length and number of microvilli on HeLa cell surface, as well as size of secreted vesicles. L. rhamnosus partially inhibits GBS-dependent microvilli and vesicle disruption. GBS also disrupts HeLa cell F-actin fibers unless L. rhamnosus is present. These results reveal effects of GBS infection on the host cell cytoskeleton and implies a protective role of L. rhamnosus against GBS colonization.
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Affiliation(s)
- Jan Mikhale Cajulao
- Department of Biology, San Francisco State University, San Francisco, CA, 94132, USA
| | - Lily Chen
- Department of Biology, San Francisco State University, San Francisco, CA, 94132, USA.
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14
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Abstract
Filopodia, microvilli and stereocilia represent an important group of plasma membrane protrusions. These specialized projections are supported by parallel bundles of actin filaments and have critical roles in sensing the external environment, increasing cell surface area, and acting as mechanosensors. While actin-associated proteins are essential for actin-filament elongation and bundling in these protrusions, myosin motors have a surprising role in the formation and extension of filopodia and stereocilia and in the organization of microvilli. Actin regulators and specific myosins collaborate in controlling the length of these structures. Myosins can transport cargoes along the length of these protrusions, and, in the case of stereocilia and microvilli, interactions with adaptors and cargoes can also serve to anchor adhesion receptors to the actin-rich core via functionally conserved motor-adaptor complexes. This review highlights recent progress in understanding the diverse roles myosins play in filopodia, microvilli and stereocilia.
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Affiliation(s)
- Anne Houdusse
- Structural Motility, Institut Curie, Paris Université Sciences et Lettres, Sorbonne Université, CNRS UMR144, 75005 Paris, France.
| | - Margaret A Titus
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
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15
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Sesorova IS, Dimov ID, Kashin AD, Sesorov VV, Karelina NR, Zdorikova MA, Beznoussenko GV, Mirоnоv AA. Cellular and sub-cellular mechanisms of lipid transport from gut to lymph. Tissue Cell 2021; 72:101529. [PMID: 33915359 DOI: 10.1016/j.tice.2021.101529] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 02/26/2021] [Accepted: 03/11/2021] [Indexed: 12/14/2022]
Abstract
Although the general structure of the barrier between the gut and the blood is well known, many details are still missing. Here, we analyse the literature and our own data related to lipid transcytosis through adult mammalian enterocytes, and their absorption into lymph at the tissue level of the intestine. After starvation, the Golgi complex (GC) of enterocytes is in a resting state. The addition of lipids in the form of chyme leads to the initial appearance of pre-chylomicrons (ChMs) in the tubules of the smooth endoplasmic reticulum, which are attached at the basolateral plasma membrane, immediately below the 'belt' of the adhesive junctions. Then pre-ChMs move into the cisternae of the rough endoplasmic reticulum and then into the expansion of the perforated Golgi cisternae. Next, they pass through the GC, and are concentrated in the distensions of the perforated cisternae on the trans-side of the GC. The arrival of pre-ChMs at the GC leads to the transition of the GC to a state of active transport, with formation of intercisternal connections, attachment of cis-most and trans-most perforated cisternae to the medial Golgi cisternae, and disappearance of COPI vesicles. Post-Golgi carriers then deliver ChMs to the basolateral plasma membrane, fuse with it, and secret ChMs into the intercellular space between enterocytes at the level of their interdigitating contacts. Finally, ChMs are squeezed out into the interstitium through pores in the basal membrane, most likely due to the function of the actin-myosin 'cuff' around the interdigitating contacts. These pores appear to be formed by protrusions of the dendritic cells and the enterocytes per se. ChMs are absorbed from the interstitium into the lymphatic capillaries through the special oblique contacts between endothelial cells, which function as valves through the contraction-relaxation of bundles of smooth muscle cells in the interstitium. Lipid overloading of enterocytes results in accumulation of cytoplasmic lipid droplets, an increase in diameter of ChMs, inhibition of intra-Golgi transport, and fusion of ChMs in the interstitium. Here, we summarise and analyse recent findings, and discuss their functional implications.
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Affiliation(s)
- Irina S Sesorova
- Department of Anatomy, Saint Petersburg State Paediatric Medical University, S. Petersburg, Russia
| | - Ivan D Dimov
- Department of Anatomy, Ivanovo State Medical Academy, Ivanovo, Russia
| | - Alexandre D Kashin
- Department of Anatomy, Saint Petersburg State Paediatric Medical University, S. Petersburg, Russia
| | - Vitaly V Sesorov
- Department of Anatomy, Saint Petersburg State Paediatric Medical University, S. Petersburg, Russia
| | | | - Maria A Zdorikova
- Department of Anatomy, Saint Petersburg State Paediatric Medical University, S. Petersburg, Russia
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16
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Mageswaran SK, Yang WY, Chakrabarty Y, Oikonomou CM, Jensen GJ. A cryo-electron tomography workflow reveals protrusion-mediated shedding on injured plasma membrane. SCIENCE ADVANCES 2021; 7:7/13/eabc6345. [PMID: 33771860 PMCID: PMC7997517 DOI: 10.1126/sciadv.abc6345] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
Cryo-electron tomography (cryo-ET) provides structural context to molecular mechanisms underlying biological processes. Although straightforward to implement for studying stable macromolecular complexes, using it to locate short-lived structures and events can be impractical. A combination of live-cell microscopy, correlative light and electron microscopy, and cryo-ET will alleviate this issue. We developed a workflow combining the three to study the ubiquitous and dynamic process of shedding in response to plasma membrane damage in HeLa cells. We found filopodia-like protrusions enriched at damage sites and acting as scaffolds for shedding, which involves F-actin dynamics, myosin-1a, and vacuolar protein sorting 4B (a component of the 'endosomal sorting complex required for transport' machinery). Overall, shedding is more complex than current models of vesiculation from flat membranes. Its similarities to constitutive shedding in enterocytes argue for a conserved mechanism. Our workflow can also be adapted to study other damage response pathways and dynamic cellular events.
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Affiliation(s)
- Shrawan Kumar Mageswaran
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
- Department of Biophysics and Biochemistry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Wei Yuan Yang
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.
| | - Yogaditya Chakrabarty
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Catherine M Oikonomou
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Grant J Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84604, USA
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17
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Hu W, Liu C, Bi ZY, Zhou Q, Zhang H, Li LL, Zhang J, Zhu W, Song YYY, Zhang F, Yang HM, Bi YY, He QQ, Tan GJ, Sun CC, Li DJ. Comprehensive landscape of extracellular vesicle-derived RNAs in cancer initiation, progression, metastasis and cancer immunology. Mol Cancer 2020; 19:102. [PMID: 32503543 PMCID: PMC7273667 DOI: 10.1186/s12943-020-01199-1] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 04/15/2020] [Indexed: 01/18/2023] Open
Abstract
Extracellular vesicles (EVs), a class of heterogeneous membrane vesicles, are generally divided into exosomes and microvesicles on basis of their origination from the endosomal membrane or the plasma membrane, respectively. EV-mediated bidirectional communication among various cell types supports cancer cell growth and metastasis. EVs derived from different cell types and status have been shown to have distinct RNA profiles, comprising messenger RNAs and non-coding RNAs (ncRNAs). Recently, ncRNAs have attracted great interests in the field of EV-RNA research, and growing numbers of ncRNAs ranging from microRNAs to long ncRNAs have been investigated to reveal their specific functions and underlying mechanisms in the tumor microenvironment and premetastatic niches. Emerging evidence has indicated that EV-RNAs are essential functional cargoes in modulating hallmarks of cancers and in reciprocal crosstalk within tumor cells and between tumor and stromal cells over short and long distance, thereby regulating the initiation, development and progression of cancers. In this review, we discuss current findings regarding EV biogenesis, release and interaction with target cells as well as EV-RNA sorting, and highlight biological roles and molecular mechanisms of EV-ncRNAs in cancer biology.
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Affiliation(s)
- Wei Hu
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Cong Liu
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Zhuo-Yue Bi
- Hubei Provincial Key Laboratory for Applied Toxicology (Hubei Provincial Academy for Preventive Medicine), Wuhan, Hubei, 430079, People's Republic of China
| | - Qun Zhou
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Han Zhang
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Lin-Lin Li
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Jian Zhang
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Wei Zhu
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Yang-Yi-Yan Song
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Feng Zhang
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Hui-Min Yang
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Yong-Yi Bi
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Qi-Qiang He
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China
| | - Gong-Jun Tan
- Department of Clinical Laboratory, Zhuhai Hospital, Jinan University, 79 Kangning Road, Zhuhai, Guangdong, 519000, People's Republic of China. .,Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA.
| | - Cheng-Cao Sun
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China. .,Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
| | - De-Jia Li
- Department of Preventive Medicine, School of Health Science, Wuhan University, No.115 Donghu Road, Wuhan, Hubei, 430071, People's Republic of China. .,Population and Health Research Center, School of Health Sciences, Wuhan University, Wuhan, Hubei, 430071, People's Republic of China.
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18
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Cytoskeletal Organization and Cell Polarity in the Pathogenesis of Crohn’s Disease. Clin Rev Allergy Immunol 2020; 60:164-174. [DOI: 10.1007/s12016-020-08795-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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Sun WW, Krystofiak ES, Leo-Macias A, Cui R, Sesso A, Weigert R, Ebrahim S, Kachar B. Nanoarchitecture and dynamics of the mouse enteric glycocalyx examined by freeze-etching electron tomography and intravital microscopy. Commun Biol 2020; 3:5. [PMID: 31925335 PMCID: PMC6946683 DOI: 10.1038/s42003-019-0735-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 12/02/2019] [Indexed: 12/21/2022] Open
Abstract
The glycocalyx is a highly hydrated, glycoprotein-rich coat shrouding many eukaryotic and prokaryotic cells. The intestinal epithelial glycocalyx, comprising glycosylated transmembrane mucins, is part of the primary host-microbe interface and is essential for nutrient absorption. Its disruption has been implicated in numerous gastrointestinal diseases. Yet, due to challenges in preserving and visualizing its native organization, glycocalyx structure-function relationships remain unclear. Here, we characterize the nanoarchitecture of the murine enteric glycocalyx using freeze-etching and electron tomography. Micrometer-long mucin filaments emerge from microvillar-tips and, through zigzagged lateral interactions form a three-dimensional columnar network with a 30 nm mesh. Filament-termini converge into globular structures ~30 nm apart that are liquid-crystalline packed within a single plane. Finally, we assess glycocalyx deformability and porosity using intravital microscopy. We argue that the columnar network architecture and the liquid-crystalline packing of the filament termini allow the glycocalyx to function as a deformable size-exclusion filter of luminal contents. Sun, Krystofiak et al. show the nanoarchitecture of the murine enteric glycocalyx, glycoprotein-rich coat covering cells and assess its porosity and deformability in mice, providing a comprehensive structural framework. This study suggests that the glycocalyx may function as a deformable size-exclusion filter of luminal contents.
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Affiliation(s)
- Willy W Sun
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA.,Neuroscience and Cognitive Science Program, University of Maryland, College Park, MD, 20740, USA
| | - Evan S Krystofiak
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Alejandra Leo-Macias
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Runjia Cui
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Antonio Sesso
- Sector of Structural Biology, Institute of Tropical Medicine, University of São Paulo, Sao Paulo, SP, 05403, Brazil
| | - Roberto Weigert
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Seham Ebrahim
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Bechara Kachar
- Laboratory of Cell Structure and Dynamics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA.
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20
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Lentle RG. Deconstructing the physical processes of digestion: reductionist approaches may provide greater understanding. Food Funct 2018; 9:4069-4084. [PMID: 30011345 DOI: 10.1039/c8fo00722e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
I provide a broad overview of the physical factors that govern intestinal digestion i.e. the admixture of food particles in digesta with secreted enzymes and the subsequent mass transfer of liberated nutrients from the surfaces of particles to the gut wall, with a view to outlining the quantitative work that is required to determine the relative importance of these factors in the digestion of particular foods. I first discuss what is known of the mechanical forces generated by contraction of the walls of the various segments of the gut and the level of diffusive, and advective mixing that it generates within the lumen. I then discuss the particular physical effects that may limit the digestion of solid, physically and/or chemically homogenous and heterogeneous food particles, notably capillarity, porosity, poro-elastic flow and compaction and their likely effects on diffusive and convective mass transfer at particulate surfaces. Similarly, I discuss mucins and morphology on mass transfer of nutrients to the gut wall i.e. the mucosa.
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Affiliation(s)
- R G Lentle
- Digestive Biomechanics Group, College of Health, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
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21
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Satir P. Chirality of the cytoskeleton in the origins of cellular asymmetry. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0408. [PMID: 27821520 DOI: 10.1098/rstb.2015.0408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2016] [Indexed: 02/06/2023] Open
Abstract
Self-assembly of two important components of the cytoskeleton of eukaryotic cells, actin microfilaments and microtubules (MTs) results in polar filaments of one chirality. As is true for bacterial flagella, in actin microfilaments, screw direction is important for assembly processes and motility. For MTs, polar orientation within the cell is paramount. The alignment of these elements in the cell cytoplasm gives rise to emergent properties, including the potential for cell differentiation and specialization. Complex MTs with a characteristic chirality are found in basal bodies and centrioles; this chirality is preserved in cilia. In motile cilia, it is reflected in the direction of the effective stroke. The positioning of the basal body or cilia on the cell surface depends on polarity proteins. In evolution, survival depends on global polarity information relayed to the cell in part by orientation of the MT and actin filament cytoskeletons and the chirality of the basal body to determine left and right coordinates within a defined anterior-posterior cell and tissue axis.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
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Affiliation(s)
- Peter Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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22
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Shashikanth N, Yeruva S, Ong MLDM, Odenwald MA, Pavlyuk R, Turner JR. Epithelial Organization: The Gut and Beyond. Compr Physiol 2017; 7:1497-1518. [DOI: 10.1002/cphy.c170003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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23
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Klunder LJ, Faber KN, Dijkstra G, van IJzendoorn SCD. Mechanisms of Cell Polarity-Controlled Epithelial Homeostasis and Immunity in the Intestine. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027888. [PMID: 28213466 DOI: 10.1101/cshperspect.a027888] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Intestinal epithelial cell polarity is instrumental to maintain epithelial homeostasis and balance communications between the gut lumen and bodily tissue, thereby controlling the defense against gastrointestinal pathogens and maintenance of immune tolerance to commensal bacteria. In this review, we highlight recent advances with regard to the molecular mechanisms of cell polarity-controlled epithelial homeostasis and immunity in the human intestine.
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Affiliation(s)
- Leon J Klunder
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Klaas Nico Faber
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Gerard Dijkstra
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
| | - Sven C D van IJzendoorn
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, the Netherlands
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24
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Nager AR, Goldstein JS, Herranz-Pérez V, Portran D, Ye F, Garcia-Verdugo JM, Nachury MV. An Actin Network Dispatches Ciliary GPCRs into Extracellular Vesicles to Modulate Signaling. Cell 2016; 168:252-263.e14. [PMID: 28017328 DOI: 10.1016/j.cell.2016.11.036] [Citation(s) in RCA: 242] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 09/14/2016] [Accepted: 11/17/2016] [Indexed: 12/13/2022]
Abstract
Signaling receptors dynamically exit cilia upon activation of signaling pathways such as Hedgehog. Here, we find that when activated G protein-coupled receptors (GPCRs) fail to undergo BBSome-mediated retrieval from cilia back into the cell, these GPCRs concentrate into membranous buds at the tips of cilia before release into extracellular vesicles named ectosomes. Unexpectedly, actin and the actin regulators drebrin and myosin 6 mediate ectosome release from the tip of cilia. Mirroring signal-dependent retrieval, signal-dependent ectocytosis is a selective and effective process that removes activated signaling molecules from cilia. Congruently, ectocytosis compensates for BBSome defects as ectocytic removal of GPR161, a negative regulator of Hedgehog signaling, permits the appropriate transduction of Hedgehog signals in Bbs mutants. Finally, ciliary receptors that lack retrieval determinants such as the anorexigenic GPCR NPY2R undergo signal-dependent ectocytosis in wild-type cells. Our data show that signal-dependent ectocytosis regulates ciliary signaling in physiological and pathological contexts.
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Affiliation(s)
- Andrew R Nager
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5345, USA
| | - Jaclyn S Goldstein
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5345, USA
| | - Vicente Herranz-Pérez
- Laboratorio de Neurobiología Comparada, Instituto Cavanilles, Universitat de València, CIBERNED, 46980 Valencia, Spain; Unidad Mixta de Esclerosis Múltiple y Neurorregeneración, IIS Hospital La Fe-UVEG, 46026 Valencia, Spain
| | - Didier Portran
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5345, USA
| | - Fan Ye
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5345, USA
| | - Jose Manuel Garcia-Verdugo
- Laboratorio de Neurobiología Comparada, Instituto Cavanilles, Universitat de València, CIBERNED, 46980 Valencia, Spain; Unidad Mixta de Esclerosis Múltiple y Neurorregeneración, IIS Hospital La Fe-UVEG, 46026 Valencia, Spain
| | - Maxence V Nachury
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305-5345, USA.
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25
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The SHIP2 interactor Myo1c is required for cell migration in 1321 N1 glioblastoma cells. Biochem Biophys Res Commun 2016; 476:508-514. [DOI: 10.1016/j.bbrc.2016.05.154] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 05/28/2016] [Indexed: 12/29/2022]
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26
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Abstract
Myosin-I molecular motors are proposed to play various cellular roles related to membrane dynamics and trafficking. In this Cell Science at a Glance article and the accompanying poster, we review and illustrate the proposed cellular functions of metazoan myosin-I molecular motors by examining the structural, biochemical, mechanical and cell biological evidence for their proposed molecular roles. We highlight evidence for the roles of myosin-I isoforms in regulating membrane tension and actin architecture, powering plasma membrane and organelle deformation, participating in membrane trafficking, and functioning as a tension-sensitive dock or tether. Collectively, myosin-I motors have been implicated in increasingly complex cellular phenomena, yet how a single isoform accomplishes multiple types of molecular functions is still an active area of investigation. To fully understand the underlying physiology, it is now essential to piece together different approaches of biological investigation. This article will appeal to investigators who study immunology, metabolic diseases, endosomal trafficking, cell motility, cancer and kidney disease, and to those who are interested in how cellular membranes are coupled to the underlying actin cytoskeleton in a variety of different applications.
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Affiliation(s)
- Betsy B McIntosh
- Pennsylvania Muscle Institute and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6085, USA
| | - E Michael Ostap
- Pennsylvania Muscle Institute and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6085, USA
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27
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Abstract
Vertebrate myosin-IC (Myo1c) is a type-1 myosin that links cell membranes to the cytoskeleton via its actin-binding motor domain and its phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2)-binding tail domain. While it is known that Myo1c bound to PtdIns(4,5)P2 in fluid-lipid bilayers can propel actin filaments in an unloaded motility assay, its ability to develop forces against external load on actin while bound to fluid bilayers has not been explored. Using optical tweezers, we measured the diffusion coefficient of single membrane-bound Myo1c molecules by force-relaxation experiments, and the ability of ensembles of membrane-bound Myo1c molecules to develop and sustain forces. To interpret our results, we developed a computational model that recapitulates the basic features of our experimental ensemble data and suggests that Myo1c ensembles can generate forces parallel to lipid bilayers, with larger forces achieved when the myosin works away from the plane of the membrane or when anchored to slowly diffusing regions.
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28
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Sauvanet C, Wayt J, Pelaseyed T, Bretscher A. Structure, Regulation, and Functional Diversity of Microvilli on the Apical Domain of Epithelial Cells. Annu Rev Cell Dev Biol 2015; 31:593-621. [DOI: 10.1146/annurev-cellbio-100814-125234] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Cécile Sauvanet
- Department of Molecular Biology and Genetics and Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, New York 14853;
| | - Jessica Wayt
- Department of Molecular Biology and Genetics and Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, New York 14853;
| | - Thaher Pelaseyed
- Department of Molecular Biology and Genetics and Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, New York 14853;
| | - Anthony Bretscher
- Department of Molecular Biology and Genetics and Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, New York 14853;
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Komaba S, Coluccio LM. Myosin 1b Regulates Amino Acid Transport by Associating Transporters with the Apical Plasma Membrane of Kidney Cells. PLoS One 2015; 10:e0138012. [PMID: 26361046 PMCID: PMC4567078 DOI: 10.1371/journal.pone.0138012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 08/24/2015] [Indexed: 01/11/2023] Open
Abstract
Amino acid transporters (AATers) in the brush border of the apical plasma membrane (APM) of renal proximal tubule (PT) cells mediate amino acid transport (AAT). We found that the membrane-associated class I myosin myosin 1b (Myo1b) localized at the apical brush border membrane of PTs. In opossum kidney (OK) 3B/2 epithelial cells, which are derived from PTs, expressed rat Myo1b-GFP colocalized in patched microvilli with expressed mouse V5-tagged SIT1 (SIT1-V5), which mediates neutral amino acid transport in OK cells. Lentivirus-mediated delivery of opossum Myo1b-specific shRNA resulted in knockdown (kd) of Myo1b expression, less SIT1-V5 at the APM as determined by localization studies, and a decrease in neutral AAT as determined by radioactive uptake assays. Myo1b kd had no effect on Pi transport or noticeable change in microvilli structure as determined by rhodamine phalloidin staining. The studies are the first to define a physiological role for Myo1b, that of regulating renal AAT by modulating the association of AATers with the APM.
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Affiliation(s)
- Shigeru Komaba
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Lynne M. Coluccio
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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Hegan PS, Kravtsov DV, Caputo C, Egan ME, Ameen NA, Mooseker MS. Restoration of cytoskeletal and membrane tethering defects but not defects in membrane trafficking in the intestinal brush border of mice lacking both myosin Ia and myosin VI. Cytoskeleton (Hoboken) 2015; 72:455-76. [PMID: 26286357 PMCID: PMC4715533 DOI: 10.1002/cm.21238] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 12/22/2022]
Abstract
Myosin Ia (Myo1a), the most prominent plus-end directed motor and myosin VI (Myo6) the sole minus-end directed motor, together exert opposing tension between the microvillar (MV) actin core and the apical brush border (BB) membrane of the intestinal epithelial cell (IEC). Mice lacking Myo1a or Myo6 each exhibit a variety of defects in the tethering of the BB membrane to the actin cytoskeleton. Double mutant (DM) mice lacking both myosins revealed that all the defects observed in either the Myo1a KO or Snell's waltzer (sv/sv) Myo6 mutant mouse are absent. In isolated DM BBs, Myo1a crosslinks between MV membrane and MV actin core are absent but the gap (which is lost in Myo1a KO) between the MV core and membrane is maintained. Several myosins including Myo1c, d, and e and Myo5a are ectopically recruited to the BB. Consistent with the restoration of membrane tethering defects by one or more of these myosins, upward ATP-driven shedding of the BB membrane, which is blocked in the Myo1a KO, is restored in the DM BB. However, Myo1a or Myo6 dependent defects in expression of membrane proteins that traffic between the BB membrane and endosome (NaPi2b, NHE3, CFTR) are not restored. Compared to controls, Myo1a KO, sv/sv mice exhibit moderate and DM high levels of hypersensitivity to dextran sulfate sodium-induced colitis. Consistent with Myo1a and Myo6 playing critical roles in maintaining IEC integrity and response to injury, DM IECs exhibit increased numbers of apoptotic nuclei, above that reported for Myo1a KO.
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Affiliation(s)
- Peter S Hegan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut
| | - Dmitri V Kravtsov
- Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut
| | - Christina Caputo
- Department of Respiratory Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Marie E Egan
- Department of Respiratory Medicine, Yale School of Medicine, New Haven, Connecticut
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
| | - Nadia A Ameen
- Department of Pediatrics/Gastroenterology and Hepatology, Yale School of Medicine, New Haven, Connecticut
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
| | - Mark S Mooseker
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
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Pathogenesis of human diffusely adhering Escherichia coli expressing Afa/Dr adhesins (Afa/Dr DAEC): current insights and future challenges. Clin Microbiol Rev 2015; 27:823-69. [PMID: 25278576 DOI: 10.1128/cmr.00036-14] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The pathogenicity and clinical pertinence of diffusely adhering Escherichia coli expressing the Afa/Dr adhesins (Afa/Dr DAEC) in urinary tract infections (UTIs) and pregnancy complications are well established. In contrast, the implication of intestinal Afa/Dr DAEC in diarrhea is still under debate. These strains are age dependently involved in diarrhea in children, are apparently not involved in diarrhea in adults, and can also be asymptomatic intestinal microbiota strains in children and adult. This comprehensive review analyzes the epidemiology and diagnosis and highlights recent progress which has improved the understanding of Afa/Dr DAEC pathogenesis. Here, I summarize the roles of Afa/Dr DAEC virulence factors, including Afa/Dr adhesins, flagella, Sat toxin, and pks island products, in the development of specific mechanisms of pathogenicity. In intestinal epithelial polarized cells, the Afa/Dr adhesins trigger cell membrane receptor clustering and activation of the linked cell signaling pathways, promote structural and functional cell lesions and injuries in intestinal barrier, induce proinflammatory responses, create angiogenesis, instigate epithelial-mesenchymal transition-like events, and lead to pks-dependent DNA damage. UTI-associated Afa/Dr DAEC strains, following adhesin-membrane receptor cell interactions and activation of associated lipid raft-dependent cell signaling pathways, internalize in a microtubule-dependent manner within urinary tract epithelial cells, develop a particular intracellular lifestyle, and trigger a toxin-dependent cell detachment. In response to Afa/Dr DAEC infection, the host epithelial cells generate antibacterial defense responses. Finally, I discuss a hypothetical role of intestinal Afa/Dr DAEC strains that can act as "silent pathogens" with the capacity to emerge as "pathobionts" for the development of inflammatory bowel disease and intestinal carcinogenesis.
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Packard M, Jokhi V, Ding B, Ruiz-Cañada C, Ashley J, Budnik V. Nucleus to Synapse Nesprin1 Railroad Tracks Direct Synapse Maturation through RNA Localization. Neuron 2015; 86:1015-1028. [PMID: 25959729 DOI: 10.1016/j.neuron.2015.04.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 02/11/2015] [Accepted: 03/27/2015] [Indexed: 10/23/2022]
Abstract
An important mechanism underlying synapse development and plasticity is the localization of mRNAs that travel from the nucleus to synaptic sites. Here we demonstrate that the giant nuclear-associated Nesprin1 (dNesp1) forms striated F-actin-based filaments, which we dubbed "railroad tracks," that span from muscle nuclei to postsynaptic sites at the neuromuscular junction in Drosophila. These railroad tracks specifically wrap around immature boutons formed during development and in response to electrical activity. In the absence of dNesp1, mRNAs normally localized at postsynaptic sites are lacking and synaptic maturation is inhibited. This dNesp1 function does not depend on direct association of dNesp1 isoforms with the nuclear envelope. We also show that dNesp1 functions with an unconventional myosin, Myo1D, and that both dNesp1 and Myo1D are mutually required for their localization to immature boutons. These studies unravel a novel pathway directing the transport of mRNAs from the nucleus to postsynaptic sites during synaptic maturation. VIDEO ABSTRACT.
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Affiliation(s)
- Mary Packard
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA
| | - Vahbiz Jokhi
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA
| | - Baojin Ding
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA
| | - Catalina Ruiz-Cañada
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA
| | - James Ashley
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA
| | - Vivian Budnik
- Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01452, USA.
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33
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Physical characterization and profiling of airway epithelial derived exosomes using light scattering. Methods 2015; 87:59-63. [PMID: 25823850 DOI: 10.1016/j.ymeth.2015.03.013] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/17/2015] [Accepted: 03/22/2015] [Indexed: 01/21/2023] Open
Abstract
Exosomes and other extracellular vesicles have been gaining interest during the last decade due to their emerging role in biology and, disease pathogenesis and their biomarker potential. Almost all published research related to exosomes and other extracellular vesicles include some form of physical characterization. Therefore, these vesicles should be precisely profiled and characterized physically before studying their biological role as intercellular messengers, biomarkers or therapeutic tools. Using a combination of light scattering techniques, including dynamic light scattering (DLS) and multi-angle laser light scattering combined with size exclusion separation (SEC-MALLS), we physically characterized and compared distinct extracellular vesicles derived from the apical secretions of two different cultured airway epithelial cells. The results indicated that epithelial cells release vesicles with distinct physical properties and sizes. Human primary tracheobronchial cell culture (HTBE) derived vesicles have a hydrodynamic radius (Rh) of approximately 340 nm while their radius of gyration (Rg) is approximately 200 nm. Electron microscopy analysis, however, revealed that their spherical component is 40-100 nm in size, and they carry filamentous, entangled membrane mucins on their surface that increases their overall radius. The mucin decoration on the surface defines their size and charge as measured using light scattering techniques. Their surface properties mirror the properties of the cells from which they are derived. This may provide a unique tool for researchers to elucidate the unanswered questions in normal airway biology and innate and adaptive defense, including the remodeling of airways during inflammation, tumorigenesis and metastasis.
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Abstract
Epithelial cells from diverse tissues, including the enterocytes that line the intestinal tract, remodel their apical surface during differentiation to form a brush border: an array of actin-supported membrane protrusions known as microvilli that increases the functional capacity of the tissue. Although our understanding of how epithelial cells assemble, stabilize, and organize apical microvilli is still developing, investigations of the biochemical and physical underpinnings of these processes suggest that cells coordinate cytoskeletal remodeling, membrane-cytoskeleton cross-linking, and extracellular adhesion to shape the apical brush border domain.
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Affiliation(s)
- Scott W Crawley
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Mark S Mooseker
- Department of Molecular, Cellular and Developmental Biology, Department of Cell Biology, and Department of Pathology, Yale University, New Haven, CT 06520 Department of Molecular, Cellular and Developmental Biology, Department of Cell Biology, and Department of Pathology, Yale University, New Haven, CT 06520 Department of Molecular, Cellular and Developmental Biology, Department of Cell Biology, and Department of Pathology, Yale University, New Haven, CT 06520
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232
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35
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The Secretion and Action of Brush Border Enzymes in the Mammalian Small Intestine. Rev Physiol Biochem Pharmacol 2015; 168:59-118. [PMID: 26345415 DOI: 10.1007/112_2015_24] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Microvilli are conventionally regarded as an extension of the small intestinal absorptive surface, but they are also, as latterly discovered, a launching pad for brush border digestive enzymes. Recent work has demonstrated that motor elements of the microvillus cytoskeleton operate to displace the apical membrane toward the apex of the microvillus, where it vesiculates and is shed into the periapical space. Catalytically active brush border digestive enzymes remain incorporated within the membranes of these vesicles, which shifts the site of BB digestion from the surface of the enterocyte to the periapical space. This process enables nutrient hydrolysis to occur adjacent to the membrane in a pre-absorptive step. The characterization of BB digestive enzymes is influenced by the way in which these enzymes are anchored to the apical membranes of microvilli, their subsequent shedding in membrane vesicles, and their differing susceptibilities to cleavage from the component membranes. In addition, the presence of active intracellular components of these enzymes complicates their quantitative assay and the elucidation of their dynamics. This review summarizes the ontogeny and regulation of BB digestive enzymes and what is known of their kinetics and their action in the peripheral and axial regions of the small intestinal lumen.
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36
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Motor and tail homology 1 (Th1) domains antagonistically control myosin-1 dynamics. Biophys J 2014; 106:649-58. [PMID: 24507605 DOI: 10.1016/j.bpj.2013.12.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/23/2013] [Accepted: 12/26/2013] [Indexed: 11/22/2022] Open
Abstract
Class 1 myosins are monomeric motor proteins that fulfill diverse functions at the membrane/cytoskeletal interface. All myosins-1 contain a motor domain, which binds actin, hydrolyzes ATP, and generates forces, and a TH1 domain, which interacts directly with membrane lipids. In most cases, TH1 is needed for proper subcellular localization and presumably function, although little is known about how this domain regulates the behavior of class 1 myosins in live cells. To address this, we used single molecule total internal reflection fluorescence microscopy to examine the dynamics of the well-characterized myosin-1a isoform during interactions with the cortex of living cells. Our studies revealed that full-length myosin-1a exhibits restricted mobility relative to TH1 alone. Motor domain mutations that disrupt actin binding increased the mobility of full-length myosin-1a, whereas mutations to the TH1 domain that are known to reduce steady-state targeting to the plasma membrane unexpectedly reduced mobility. Deletion of the calmodulin-binding lever arm in Myo1a mimicked the impact of actin-binding mutations. Finally, myosin-1b, which demonstrates exquisite sensitivity to mechanical load, exhibited dynamic behavior nearly identical to myosin-1a. These studies are the first, to our knowledge, to explore class 1 myosin dynamics at the single-molecule level in living cells; our results suggest a model where the motor domain restricts dynamics via a mechanism that requires the lever arm, whereas the TH1 domain allows persistent diffusion in close proximity to the plasma membrane.
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37
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Ouderkirk JL, Krendel M. Non-muscle myosins in tumor progression, cancer cell invasion, and metastasis. Cytoskeleton (Hoboken) 2014; 71:447-63. [PMID: 25087729 DOI: 10.1002/cm.21187] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 07/28/2014] [Accepted: 07/29/2014] [Indexed: 02/06/2023]
Abstract
The actin cytoskeleton, which regulates cell polarity, adhesion, and migration, can influence cancer progression, including initial acquisition of malignant properties by normal cells, invasion of adjacent tissues, and metastasis to distant sites. Actin-dependent molecular motors, myosins, play key roles in regulating tumor progression and metastasis. In this review, we examine how non-muscle myosins regulate neoplastic transformation and cancer cell migration and invasion. Members of the myosin superfamily can act as either enhancers or suppressors of tumor progression. This review summarizes the current state of knowledge on how mutations or epigenetic changes in myosin genes and changes in myosin expression may affect tumor progression and patient outcomes and discusses the proposed mechanisms linking myosin inactivation or upregulation to malignant phenotype, cancer cell migration, and metastasis.
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Affiliation(s)
- Jessica L Ouderkirk
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, 750 E. Adams St., Syracuse, New York
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38
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Shifrin DA, Demory Beckler M, Coffey RJ, Tyska MJ. Extracellular vesicles: communication, coercion, and conditioning. Mol Biol Cell 2013; 24:1253-9. [PMID: 23630232 PMCID: PMC3639038 DOI: 10.1091/mbc.e12-08-0572] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cells communicate with neighboring cells and condition their local environment by secreting soluble factors into the extracellular space. These well-studied facets of cell biology are essential for the establishment and maintenance of physiological homeostasis. However, accumulating evidence has revealed that specific ligands, enzymes, and macromolecules are distributed into the extracellular space by virtue of their association with small vesicles, which are released by a variety of cell types. Although the biological significance of such vesicles was initially debated, purification and subsequent functional studies have shown that these extracellular vesicles are bioactive organelles carrying a wide range of protein and nucleic acid cargoes. In many cases these vesicles are laden with molecules that are involved in cell signaling, although other diverse functions are being revealed at a rapid pace. In this Perspective, we discuss recent developments in the understanding of the major pathways of extracellular vesicle biogenesis and how these vesicles contribute to the maintenance of physiological homeostasis.
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Affiliation(s)
- David A Shifrin
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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39
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Affiliation(s)
- M Amanda Hartman
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
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40
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Prominin-1-containing membrane vesicles: origins, formation, and utility. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 777:41-54. [PMID: 23161074 DOI: 10.1007/978-1-4614-5894-4_3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The stem cell antigen prominin-1 (CD133) is associated with two major types (small and large) of extracellular membrane vesicles in addition to its selective concentration in various kinds of plasma membrane protrusion. During development of the mammalian central nervous system, differentiating neuroepithelial stem cells release these vesicles into the embryonic cerebrospinal fluid. In glioblastoma patients, an increase of such vesicles, particularly the smaller ones, have been also observed in cerebrospinal fluid. Similarly, hematopoietic stem and progenitor cells release small ones concomitantly with their differentiation. Although the functional significance of these prominin-1-containing membrane vesicles is poorly understood, a link between differentiation of stem (and cancer stem) cells and their release is emerging. In this chapter, I will summarize our knowledge about prominin-1-containing membrane vesicles including a potential role in cell-cell communication and highlight their prospective value as a new biomarker for tumorigenesis diagnostics.
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41
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Greenberg MJ, Ostap EM. Regulation and control of myosin-I by the motor and light chain-binding domains. Trends Cell Biol 2012. [PMID: 23200340 DOI: 10.1016/j.tcb.2012.10.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Members of the myosin-I family of molecular motors are expressed in many eukaryotes, where they are involved in a multitude of critical processes. Humans express eight distinct members of the myosin-I family, making it the second largest family of myosins expressed in humans. Despite the high degree of sequence conservation in the motor and light chain-binding domains (LCBDs) of these myosins, recent studies have revealed surprising diversity of function and regulation arising from isoform-specific differences in these domains. Here we review the regulation of myosin-I function and localization by the motor and LCBDs.
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Affiliation(s)
- Michael J Greenberg
- The Pennsylvania Muscle Institute and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6085, USA
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42
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Shifrin, Jr DA, Tyska MJ. Ready…aim…fire into the lumen: a new role for enterocyte microvilli in gut host defense. Gut Microbes 2012; 3:460-2. [PMID: 22825496 PMCID: PMC3466500 DOI: 10.4161/gmic.21247] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Recent studies from our laboratory revealed that enterocyte brush border microvilli release small vesicles laden with host defense machinery into the intestinal lumen. In this addendum, we introduce a multi-faceted model for the function of these lumenal vesicles in the gut; we also consider some of the important unanswered questions that must be addressed in order to develop our understanding of this novel aspect of innate intestinal immunity.
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43
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Kravtsov DV, Caputo C, Collaco A, Hoekstra N, Egan ME, Mooseker MS, Ameen NA. Myosin Ia is required for CFTR brush border membrane trafficking and ion transport in the mouse small intestine. Traffic 2012; 13:1072-82. [PMID: 22510086 DOI: 10.1111/j.1600-0854.2012.01368.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 04/12/2012] [Accepted: 04/17/2012] [Indexed: 12/16/2022]
Abstract
In enterocytes of the small intestine, endocytic trafficking of CFTR channels from the brush border membrane (BBM) to the subapical endosomes requires the minus-end motor, myosin VI (Myo6). The subapical localization of Myo6 is dependent on myosin Ia (Myo1a) the major plus-end motor associated with the BBM, suggestive of functional synergy between these two motors. In villus enterocytes of the Myo1a KO mouse small intestine, CFTR accumulated in syntaxin-3 positive subapical endosomes, redistributed to the basolateral domain and was absent from the BBM. In colon, where villi are absent and Myo1a expression is low, CFTR exhibited normal localization to the BBM in the Myo1a KO similar to WT. cAMP-stimulated CFTR anion transport in the small intestine was reduced by 58% in the KO, while anion transport in the colon was comparable to WT. Co-immunoprecipitation confirmed the association of CFTR with Myo1a. These data indicate that Myo1a is an important regulator of CFTR traffic and anion transport in the BBM of villus enterocytes and suggest that Myo1a may power apical CFTR movement into the BBM from subapical endosomes. Alternatively, it may anchor CFTR channels in the BBM of villus enterocytes as was proposed for Myo1a's role in BBM localization of sucrase-isomaltase.
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Affiliation(s)
- Dmitri V Kravtsov
- Department of Pediatrics/Gastroenterology & Hepatology, Yale University School of Medicine, 333 Cedar Street, FMP 408, P.O. Box 208064, New Haven, CT 06520, USA
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44
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Shifrin DA, McConnell RE, Nambiar R, Higginbotham JN, Coffey RJ, Tyska MJ. Enterocyte microvillus-derived vesicles detoxify bacterial products and regulate epithelial-microbial interactions. Curr Biol 2012; 22:627-31. [PMID: 22386311 DOI: 10.1016/j.cub.2012.02.022] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 01/03/2012] [Accepted: 02/08/2012] [Indexed: 10/28/2022]
Abstract
The continuous monolayer of intestinal epithelial cells (IECs) lining the gut lumen functions as the site of nutrient absorption and as a physical barrier to prevent the translocation of microbes and associated toxic compounds into the peripheral vasculature. IECs also express host defense proteins such as intestinal alkaline phosphatase (IAP), which detoxify bacterial products and prevent intestinal inflammation. Our laboratory recently showed that IAP is enriched on vesicles that are released from the tips of IEC microvilli and accumulate in the intestinal lumen. Here, we show that these native "lumenal vesicles" (LVs) (1) contain catalytically active IAP that can dephosphorylate lipopolysaccharide (LPS), (2) cluster on the surface of native lumenal bacteria, (3) prevent the adherence of enteropathogenic E. coli (EPEC) to epithelial monolayers, and (4) limit bacterial population growth. We also find that IECs upregulate LV production in response to EPEC and other Gram-negative pathogens. Together, these results suggest that microvillar vesicle shedding represents a novel mechanism for distributing host defense machinery into the intestinal lumen and that microvillus-derived LVs modulate epithelial-microbial interactions.
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Affiliation(s)
- David A Shifrin
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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45
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Stevenson RP, Veltman D, Machesky LM. Actin-bundling proteins in cancer progression at a glance. J Cell Sci 2012; 125:1073-9. [PMID: 22492983 DOI: 10.1242/jcs.093799] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Richard P Stevenson
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Rd, Bearsden, Glasgow G61 1BD, UK
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46
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Mazerik JN, Tyska MJ. Myosin-1A targets to microvilli using multiple membrane binding motifs in the tail homology 1 (TH1) domain. J Biol Chem 2012; 287:13104-15. [PMID: 22367206 DOI: 10.1074/jbc.m111.336313] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
One of the most abundant components of the enterocyte brush border is the actin-based monomeric motor, myosin-1a (Myo1a). Within brush border microvilli, Myo1a carries out a number of critical functions at the interface between membrane and actin cytoskeleton. Proper physiological function of Myo1a depends on its ability to bind to microvillar membrane, an interaction mediated by a C-terminal tail homology 1 (TH1) domain. However, little is known about the mechanistic details of the Myo1a-TH1/membrane interaction. Structure-function analysis of Myo1a-TH1 targeting in epithelial cells revealed that an N-terminal motif conserved among class I myosins and a C-terminal motif unique to Myo1a-TH1 are both required for steady state microvillar enrichment. Purified Myo1a bound to liposomes composed of phosphatidylserine and phosphoinositol 4,5-bisphosphate, with moderate affinity in a charge-dependent manner. Additionally, peptides of the N- and C-terminal regions required for targeting were able to compete with Myo1a for binding to highly charged liposomes in vitro. Single molecule total internal reflection fluorescence microscopy showed that these motifs are also necessary for slowing the membrane detachment rate in cells. Finally, Myo1a-TH1 co-localized with both lactadherin-C2 (a phosphatidylserine-binding protein) and PLCδ1-PH (a phosphoinositol 4,5-bisphosphate-binding protein) in microvilli, but only lactaderin-C2 expression reduced brush border targeting of Myo1a-TH1. Together, our results suggest that Myo1a targeting to microvilli is driven by membrane binding potential that is distributed throughout TH1 rather than localized to a single motif. These data highlight the diversity of mechanisms that enable different class I myosins to target membranes in distinct biological contexts.
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Affiliation(s)
- Jessica N Mazerik
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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47
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Revenu C, Ubelmann F, Hurbain I, El-Marjou F, Dingli F, Loew D, Delacour D, Gilet J, Brot-Laroche E, Rivero F, Louvard D, Robine S. A new role for the architecture of microvillar actin bundles in apical retention of membrane proteins. Mol Biol Cell 2011; 23:324-36. [PMID: 22114352 PMCID: PMC3258176 DOI: 10.1091/mbc.e11-09-0765] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The bundled architecture of actin filaments is not needed for intestinal microvillar morphogenesis, as shown in knockout mice devoid of microvillar actin-bundling proteins. This architecture is essential for the apical anchorage of digestive proteins, probably via the recruitment of key players in apical retention, such as myosin-1a, and, as a result, for intestinal physiology. Actin-bundling proteins are identified as key players in the morphogenesis of thin membrane protrusions. Until now, functional redundancy among the actin-bundling proteins villin, espin, and plastin-1 has prevented definitive conclusions regarding their role in intestinal microvilli. We report that triple knockout mice lacking these microvillar actin-bundling proteins suffer from growth delay but surprisingly still develop microvilli. However, the microvillar actin filaments are sparse and lack the characteristic organization of bundles. This correlates with a highly inefficient apical retention of enzymes and transporters that accumulate in subapical endocytic compartments. Myosin-1a, a motor involved in the anchorage of membrane proteins in microvilli, is also mislocalized. These findings illustrate, in vivo, a precise role for local actin filament architecture in the stabilization of apical cargoes into microvilli. Hence, the function of actin-bundling proteins is not to enable microvillar protrusion, as has been assumed, but to confer the appropriate actin organization for the apical retention of proteins essential for normal intestinal physiology.
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Affiliation(s)
- Céline Revenu
- Unité Mixte de Recherche 144, Centre National de la Recherche Scientifique, Institut Curie, 75248 Paris, Cedex 05, France.
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Ohta K, Higashi R, Sawaguchi A, Nakamura KI. Helical arrangement of filaments in microvillar actin bundles. J Struct Biol 2011; 177:513-9. [PMID: 22085749 DOI: 10.1016/j.jsb.2011.10.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Revised: 09/28/2011] [Accepted: 10/30/2011] [Indexed: 11/29/2022]
Abstract
Actin filament arrays in in vivo microvillar bundles of rat intestinal enterocyte were re-evaluated using electron tomography (ET). Conventional electron microscope observation of semi-thin cross sections (300nm thick) of high-pressure freeze fixed and resin embedded brush border has shown a whirling pattern in the center of the microvilli instead of hexagonally arranged dots, which strongly suggests that the bundle consists of a non-parallel array of filaments. A depth compensation method for the ET was developed to estimate the actual structure of the actin bundle. Specimen shrinkage by beam irradiation during image acquisition was estimated to be 63%, and we restored the original thickness in the reconstruction. The depth compensated tomogram displayed the individual actin filaments within the bundles and it indicated that the actin filaments do not lie exactly parallel to each other: instead, they are twisted in a clockwise coil with a pitch of ∼120°/μm. Furthermore, the lattice of actin filaments was occasionally re-arranged within the bundle. As the microvillar bundle mechanically interacts with the membrane and is thought to be compressed by the membrane's faint tensile force, we removed the shrouding membrane using detergents to eliminate the mechanical interaction. The bared bundles no longer showed the whirling pattern, suggesting that the bundle had released its coiled property. These findings indicate that the bundle has not rigid but elastic properties and a dynamic transformation in its structure caused by a change in the mechanical interaction between the membrane and the bundle.
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Affiliation(s)
- Keisuke Ohta
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka 830-0011, Japan.
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Maravillas-Montero JL, Gillespie PG, Patiño-López G, Shaw S, Santos-Argumedo L. Myosin 1c participates in B cell cytoskeleton rearrangements, is recruited to the immunologic synapse, and contributes to antigen presentation. THE JOURNAL OF IMMUNOLOGY 2011; 187:3053-63. [PMID: 21841128 DOI: 10.4049/jimmunol.1004018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Myosin 1c (Myo1c) is a member of the unconventional class I myosins of vertebrates, which directly link the plasma membrane with the microfilament cortical web. Although this molecular motor has been implicated in cell functions such as cytoskeleton organization, cell motility, nuclear transcription, and endocytosis, its role in hematopoietic cells is largely unknown. In this study, we show that Myo1c is abundantly expressed in murine B lymphocytes and is preferentially located at the plasma membrane, especially in peripheral processes such as microvilli. We observed that this motor concentrates at the growing membrane protrusions generated during B cell spreading and that it is actively recruited to the immune synapse. Interestingly, Myo1c was detected in lipid rafts of B cells and showed strong colocalization with MHC-II, particularly after cross-linking of these molecules. By transfection of a dominant negative form of Myo1c or specific siRNA, we also detected alterations in the spreading and Ag-presenting ability of these cells. The data suggest that Myo1c is involved in the cytoskeleton dynamics and membrane protein anchoring or sorting in B lymphocytes.
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Affiliation(s)
- José L Maravillas-Montero
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City CP 07360, México
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Lymphocyte α-kinase is a gout-susceptible gene involved in monosodium urate monohydrate-induced inflammatory responses. J Mol Med (Berl) 2011; 89:1241-51. [PMID: 21822924 DOI: 10.1007/s00109-011-0796-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 07/04/2011] [Accepted: 07/22/2011] [Indexed: 10/17/2022]
Abstract
The molecular functions and pathophysiologic role of the lymphocyte α-kinase gene (ALPK1) in gout are unknown. We aimed to examine ALPK1 expression in patients with gout and investigate its role in monosodium urate monohydrate (MSU)-induced inflammatory responses. Microarray data mining was performed with six datasets containing three clinical gout and three volunteer samples. Real-time quantitative polymerase chain reaction (qPCR) assay was used to profile ALPK1 mRNA expression in 62 independent samples. RNA interference for ALPK1 suppression in THP1 cells (human monocytic cell line) was used to scrutinize the functional role of ALPK1 in MSU-mediated inflammatory responses, and ALPK1 expression in MSU-treated THP1 cells was determined by qPCR and Western blot analysis. Cytokine mRNA expression in HEK293 cells after incubation with different concentrations of MSU crystals in the presence or absence of ALPK1 was also detected by qPCR, and ERK1/2, p38, and JNK expressions were investigated by Western blot analysis. ALPK1 mRNA was overexpressed in the clinical gout samples. MSU treatment promoted ALPK1 expression at the mRNA and protein levels. Furthermore, ALPK1 knockdown in THP1 cells resulted in a markedly decreased IL-1β, TNF-α, and IL-8 mRNA expression; plasmid ALPK1 transfection and MSU stimulation synergistically increased the mRNA expression of these cytokines in a concentration-dependent manner. The synergistic effect also led to ERK1/2 activation. ALPK1 is a gout-susceptible gene involved in MSU-induced inflammatory responses. It may contribute to the development of gout by enhancing the inflammatory responses via the mitogen-activated protein kinase pathway.
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