1
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Bildstein T, Charbit-Henrion F, Azabdaftari A, Cerf-Bensussan N, Uhlig HH. Cellular and molecular basis of proximal small intestine disorders. Nat Rev Gastroenterol Hepatol 2024:10.1038/s41575-024-00962-9. [PMID: 39117867 DOI: 10.1038/s41575-024-00962-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/28/2024] [Indexed: 08/10/2024]
Abstract
The proximal part of the small intestine, including duodenum and jejunum, is not only dedicated to nutrient digestion and absorption but is also a highly regulated immune site exposed to environmental factors. Host-protective responses against pathogens and tolerance to food antigens are essential functions in the small intestine. The cellular ecology and molecular pathways to maintain those functions are complex. Maladaptation is highlighted by common immune-mediated diseases such as coeliac disease, environmental enteric dysfunction or duodenal Crohn's disease. An expanding spectrum of more than 100 rare monogenic disorders inform on causative molecular mechanisms of nutrient absorption, epithelial homeostasis and barrier function, as well as inflammatory immune responses and immune regulation. Here, after summarizing the architectural and cellular traits that underlie the functions of the proximal intestine, we discuss how the integration of tissue immunopathology and molecular mechanisms can contribute towards our understanding of disease and guide diagnosis. We propose an integrated mechanism-based taxonomy and discuss the latest experimental approaches to gain new mechanistic insight into these disorders with large disease burden worldwide as well as implications for therapeutic interventions.
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Affiliation(s)
- Tania Bildstein
- Great Ormond Street Hospital for Children, Department of Paediatric Gastroenterology, London, UK
| | - Fabienne Charbit-Henrion
- Department of Genomic Medicine for Rare Diseases, Necker-Enfants Malades Hospital, APHP, University of Paris-Cité, Paris, France
- INSERM UMR1163, Intestinal Immunity, Institut Imagine, Paris, France
| | - Aline Azabdaftari
- Translational Gastroenterology Unit, Nuffield Department of Medicine, Oxford, UK
| | | | - Holm H Uhlig
- Translational Gastroenterology Unit, Nuffield Department of Medicine, Oxford, UK.
- Department of Paediatrics, University of Oxford, Oxford, UK.
- National Institute for Health and Care Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK.
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2
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Kaji I, Thiagarajah JR, Goldenring JR. Modeling the cell biology of monogenetic intestinal epithelial disorders. J Cell Biol 2024; 223:e202310118. [PMID: 38683247 PMCID: PMC11058565 DOI: 10.1083/jcb.202310118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 04/02/2024] [Accepted: 04/15/2024] [Indexed: 05/01/2024] Open
Abstract
Monogenetic variants are responsible for a range of congenital human diseases. Variants in genes that are important for intestinal epithelial function cause a group of disorders characterized by severe diarrhea and loss of nutrient absorption called congenital diarrheas and enteropathies (CODEs). CODE-causing genes include nutrient transporters, enzymes, structural proteins, and vesicular trafficking proteins in intestinal epithelial cells. Several severe CODE disorders result from the loss-of-function in key regulators of polarized endocytic trafficking such as the motor protein, Myosin VB (MYO5B), as well as STX3, STXBP2, and UNC45A. Investigations of the cell biology and pathophysiology following loss-of-function in these genes have led to an increased understanding of both homeostatic and pathological vesicular trafficking in intestinal epithelial cells. Modeling different CODEs through investigation of changes in patient tissues, coupled with the development of animal models and patient-derived enteroids, has provided critical insights into the enterocyte differentiation and function. Linking basic knowledge of cell biology with the phenotype of specific patient variants is a key step in developing effective treatments for rare monogenetic diseases. This knowledge can also be applied more broadly to our understanding of common epithelial disorders.
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Affiliation(s)
- Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jay R. Thiagarajah
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- Congenital Enteropathy Program, Boston Children’s Hospital, Boston, MA, USA
- Harvard Digestive Disease Center, Boston, MA, USA
| | - James R. Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Nashville VA Medical Center, Nashville, TN, USA
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3
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Pasquier N, Jaulin F, Peglion F. Inverted apicobasal polarity in health and disease. J Cell Sci 2024; 137:jcs261659. [PMID: 38465512 PMCID: PMC10984280 DOI: 10.1242/jcs.261659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024] Open
Abstract
Apicobasal epithelial polarity controls the functional properties of most organs. Thus, there has been extensive research on the molecular intricacies governing the establishment and maintenance of cell polarity. Whereas loss of apicobasal polarity is a well-documented phenomenon associated with multiple diseases, less is known regarding another type of apicobasal polarity alteration - the inversion of polarity. In this Review, we provide a unifying definition of inverted polarity and discuss multiple scenarios in mammalian systems and human health and disease in which apical and basolateral membrane domains are interchanged. This includes mammalian embryo implantation, monogenic diseases and dissemination of cancer cell clusters. For each example, the functional consequences of polarity inversion are assessed, revealing shared outcomes, including modifications in immune surveillance, altered drug sensitivity and changes in adhesions to neighboring cells. Finally, we highlight the molecular alterations associated with inverted apicobasal polarity and provide a molecular framework to connect these changes with the core cell polarity machinery and to explain roles of polarity inversion in health and disease. Based on the current state of the field, failure to respond to extracellular matrix (ECM) cues, increased cellular contractility and membrane trafficking defects are likely to account for most cases of inverted apicobasal polarity.
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Affiliation(s)
- Nicolas Pasquier
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
- Cell Adhesion and Cancer lab, University of Turku, FI-20520 Turku, Finland
| | - Fanny Jaulin
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
| | - Florent Peglion
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
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4
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Kalashyan M, Raghunathan K, Oller H, Bayer MT, Jimenez L, Roland JT, Kolobova E, Hagen SJ, Goldsmith JD, Shub MD, Goldenring JR, Kaji I, Thiagarajah JR. Patient-derived enteroids provide a platform for the development of therapeutic approaches in microvillus inclusion disease. J Clin Invest 2023; 133:e169234. [PMID: 37643022 PMCID: PMC10575727 DOI: 10.1172/jci169234] [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: 01/31/2023] [Accepted: 08/22/2023] [Indexed: 08/31/2023] Open
Abstract
Microvillus inclusion disease (MVID), caused by loss-of-function mutations in the motor protein myosin Vb (MYO5B), is a severe infantile disease characterized by diarrhea, malabsorption, and acid/base instability, requiring intensive parenteral support for nutritional and fluid management. Human patient-derived enteroids represent a model for investigation of monogenic epithelial disorders but are a rare resource from MVID patients. We developed human enteroids with different loss-of function MYO5B variants and showed that they recapitulated the structural changes found in native MVID enterocytes. Multiplex immunofluorescence imaging of patient duodenal tissues revealed patient-specific changes in localization of brush border transporters. Functional analysis of electrolyte transport revealed profound loss of Na+/H+ exchange (NHE) activity in MVID patient enteroids with near-normal chloride secretion. The chloride channel-blocking antidiarrheal drug crofelemer dose-dependently inhibited agonist-mediated fluid secretion. MVID enteroids exhibited altered differentiation and maturation versus healthy enteroids. γ-Secretase inhibition with DAPT recovered apical brush border structure and functional Na+/H+ exchange activity in MVID enteroids. Transcriptomic analysis revealed potential pathways involved in the rescue of MVID cells including serum/glucocorticoid-regulated kinase 2 (SGK2) and NHE regulatory factor 3 (NHERF3). These results demonstrate the utility of patient-derived enteroids for developing therapeutic approaches to MVID.
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Affiliation(s)
- Meri Kalashyan
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Krishnan Raghunathan
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Haley Oller
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Marie-Theres Bayer
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Lissette Jimenez
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Congenital Enteropathy Program, Boston Children’s Hospital, Boston, Massachusetts, USA
- PediCODE Consortium, as detailed in Supplemental Acknowledgments
| | - Joseph T. Roland
- Section of Surgical Sciences and
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Elena Kolobova
- Section of Surgical Sciences and
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Susan J. Hagen
- Department of Surgery, Division of Surgical Sciences, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Jeffrey D. Goldsmith
- PediCODE Consortium, as detailed in Supplemental Acknowledgments
- Department of Pathology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Mitchell D. Shub
- Department of Child Health, University of Arizona College of Medicine–Phoenix, and Division of Gastroenterology, Phoenix Children’s Hospital, Phoenix, Arizona, USA
| | - James R. Goldenring
- PediCODE Consortium, as detailed in Supplemental Acknowledgments
- Section of Surgical Sciences and
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Nashville VA Medical Center, Nashville, Tennessee, USA
| | - Izumi Kaji
- PediCODE Consortium, as detailed in Supplemental Acknowledgments
- Section of Surgical Sciences and
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jay R. Thiagarajah
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Congenital Enteropathy Program, Boston Children’s Hospital, Boston, Massachusetts, USA
- PediCODE Consortium, as detailed in Supplemental Acknowledgments
- Harvard Digestive Disease Center, Boston, Massachusetts, USA
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5
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Xie S, Wei S, Ma X, Wang R, He T, Zhang Z, Yang J, Wang J, Chang L, Jing M, Li H, Zhou X, Zhao Y. Genetic alterations and molecular mechanisms underlying hereditary intrahepatic cholestasis. Front Pharmacol 2023; 14:1173542. [PMID: 37324459 PMCID: PMC10264785 DOI: 10.3389/fphar.2023.1173542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/16/2023] [Indexed: 06/17/2023] Open
Abstract
Hereditary cholestatic liver disease caused by a class of autosomal gene mutations results in jaundice, which involves the abnormality of the synthesis, secretion, and other disorders of bile acids metabolism. Due to the existence of a variety of gene mutations, the clinical manifestations of children are also diverse. There is no unified standard for diagnosis and single detection method, which seriously hinders the development of clinical treatment. Therefore, the mutated genes of hereditary intrahepatic cholestasis were systematically described in this review.
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Affiliation(s)
- Shuying Xie
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Shizhang Wei
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
| | - Xiao Ma
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ruilin Wang
- Department of Pharmacy, 5th Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Tingting He
- Department of Pharmacy, 5th Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Zhao Zhang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ju Yang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jiawei Wang
- Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Lei Chang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Manyi Jing
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
| | - Haotian Li
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
| | - Xuelin Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yanling Zhao
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- Department of Pharmacy, Chinese PLA General Hospital, Beijing, China
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6
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Kalashyan M, Raghunathan K, Oller H, Theres MB, Jimenez L, Roland JT, Kolobova E, Hagen SJ, Goldsmith JD, Shub MD, Goldenring JR, Kaji I, Thiagarajah JR. Therapy Development for Microvillus Inclusion Disease using Patient-derived Enteroids. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.28.526036. [PMID: 36747680 PMCID: PMC9900906 DOI: 10.1101/2023.01.28.526036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Microvillus Inclusion Disease (MVID), caused by loss-of-function mutations in the motor protein Myosin Vb (MYO5B), is a severe infantile disease characterized by diarrhea, malabsorption, and acid-base instability, requiring intensive parenteral support for nutritional and fluid management. Human patient-derived enteroids represent a model for investigation of monogenic epithelial disorders but are a rare resource from MVID patients. We developed human enteroids with different loss-of function MYO5B variants and showed that they recapitulated the structural changes found in native MVID enterocytes. Multiplex Immunofluorescence imaging of patient duodenal tissues revealed patient-specific changes in localization of brush border transporters. Functional analysis of electrolyte transport revealed profound loss of Na + /H + exchange (NHE) activity in MVID patient enteroids with near-normal chloride secretion. The chloride channel-blocking anti-diarrheal drug, Crofelemer, dose-dependently inhibited agonist-mediated fluid secretion. MVID enteroids exhibited altered differentiation and maturation versus healthy enteroids. Inhibition of Notch signaling with the γ-secretase inhibitor, DAPT, recovered apical brush border structure and functional Na + /H + exchange activity in MVID enteroids. Transcriptomic analysis revealed potential pathways involved in the rescue of MVID cells including serum- and glucocorticoid-induced protein kinase 2 (SGK2), and NHE regulatory factor 3 (NHERF3). These results demonstrate the utility of patient-derived enteroids for developing therapeutic approaches to MVID. Conflict-of-interest statement The authors have declared that no conflict of interest exists.
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Affiliation(s)
- Meri Kalashyan
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
| | - Krishnan Raghunathan
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
| | - Haley Oller
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
| | - Marie-Bayer Theres
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
| | - Lissette Jimenez
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
- Congenital Enteropathy Program, Boston Children’s Hospital, Boston, MA
- PediCoDE Consortium
| | - Joseph T. Roland
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Elena Kolobova
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Susan J Hagen
- Department of Surgery, Division of Surgical Sciences, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Jeffrey D. Goldsmith
- Department of Pathology, Boston Children’s Hospital; Harvard Medical School, Boston, MA
- PediCoDE Consortium
| | - Mitchell D. Shub
- Department of Child Health University of Arizona College of Medicine-Phoenix and Division of Gastroenterology, Phoenix Children’s
| | - James R. Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
- Nashville VA Medical Center, Nashville, TN
- PediCoDE Consortium
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
- PediCoDE Consortium
| | - Jay R. Thiagarajah
- Division of Gastroenterology, Hepatology and Nutrition, Boston Children’s Hospital; Harvard Medical School, Boston, MA
- Congenital Enteropathy Program, Boston Children’s Hospital, Boston, MA
- Harvard Digestive Disease Center, Boston MA
- PediCoDE Consortium
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7
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Burman A, Momoh M, Sampson L, Skelton J, Roland JT, Ramos C, Krystofiak E, Acra S, Goldenring JR, Kaji I. Modeling of a Novel Patient-Based MYO5B Point Mutation Reveals Insights Into MVID Pathogenesis. Cell Mol Gastroenterol Hepatol 2022; 15:1022-1026. [PMID: 36592862 PMCID: PMC10041088 DOI: 10.1016/j.jcmgh.2022.12.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/20/2022] [Accepted: 12/23/2022] [Indexed: 01/04/2023]
Affiliation(s)
- Andreanna Burman
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Michael Momoh
- Epithelial Biology Center, Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Leesa Sampson
- Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee
| | - Jennifer Skelton
- Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee
| | - Joseph T Roland
- Epithelial Biology Center, Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Cynthia Ramos
- Epithelial Biology Center, Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Evan Krystofiak
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee
| | - Sari Acra
- Division of Pediatric Gastroenterology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - James R Goldenring
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee; Epithelial Biology Center, Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Nashville VA Medical Center, Nashville, Tennessee
| | - Izumi Kaji
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee; Epithelial Biology Center, Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee.
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8
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Wei Y, Wang K, Xia Q, Li B, Liu L. 3D diversiform dynamic process of microvilli in living cells. Biochem Biophys Res Commun 2022; 635:114-119. [DOI: 10.1016/j.bbrc.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 09/17/2022] [Accepted: 10/01/2022] [Indexed: 11/25/2022]
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Cartón-García F, Brotons B, Anguita E, Dopeso H, Tarragona J, Nieto R, García-Vidal E, Macaya I, Zagyva Z, Dalmau M, Sánchez-Martín M, van Ijzendoorn SCD, Landolfi S, Hernandez-Losa J, Schwartz Jr S, Matias-Guiu X, Ramón y Cajal S, Martínez-Barriocanal Á, Arango D. Myosin Vb as a tumor suppressor gene in intestinal cancer. Oncogene 2022; 41:5279-5288. [DOI: 10.1038/s41388-022-02508-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 10/08/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022]
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10
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Dooley SA, Engevik KA, Digrazia J, Stubler R, Kaji I, Krystofiak E, Engevik AC. Myosin 5b is required for proper localization of the intermicrovillar adhesion complex in the intestinal brush border. Am J Physiol Gastrointest Liver Physiol 2022; 323:G501-G510. [PMID: 36218265 PMCID: PMC9639760 DOI: 10.1152/ajpgi.00212.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 01/31/2023]
Abstract
Intestinal enterocytes have an elaborate apical membrane of actin-rich protrusions known as microvilli. The organization of microvilli is orchestrated by the intermicrovillar adhesion complex (IMAC), which connects the distal tips of adjacent microvilli. The IMAC is composed of CDHR2 and CDHR5 as well as the scaffolding proteins USH1C, ANKS4B, and Myosin 7b (MYO7B). To create an IMAC, cells must transport the proteins to the apical membrane. Myosin 5b (MYO5B) is a molecular motor that traffics ion transporters to the apical membrane of enterocytes, and we hypothesized that MYO5B may also be responsible for the localization of IMAC proteins. To address this question, we used two different mouse models: 1) neonatal germline MYO5B knockout (MYO5B KO) mice and 2) adult intestinal-specific tamoxifen-inducible VillinCreERT2;MYO5Bflox/flox mice. In control mice, immunostaining revealed that CDHR2, CDHR5, USH1C, and MYO7B were highly enriched at the tips of the microvilli. In contrast, neonatal germline and adult MYO5B-deficient mice showed loss of apical CDHR2, CDHR5, and MYO7B in the brush border and accumulation in a subapical compartment. Colocalization analysis revealed decreased Mander's coefficients in adult inducible MYO5B-deficient mice compared with control mice for CDHR2, CDHR5, USH1C, and MYO7B. Scanning electron microscopy images further demonstrated aberrant microvilli packing in adult inducible MYO5B-deficient mouse small intestine. These data indicate that MYO5B is responsible for the delivery of IMAC components to the apical membrane.NEW & NOTEWORTHY The intestinal epithelium absorbs nutrients and water through an elaborate apical membrane of highly organized microvilli. Microvilli organization is regulated by the intermicrovillar adhesion complexes, which create links between neighboring microvilli and control microvilli packing and density. In this study, we report a new trafficking partner of the IMAC, Myosin 5b. Loss of Myosin 5b results in a disorganized brush border and failure of IMAC proteins to reach the distal tips of microvilli.
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Affiliation(s)
- Sarah A Dooley
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Kristen A Engevik
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas
| | - Jessica Digrazia
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Rachel Stubler
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Evan Krystofiak
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee
- Cell Imaging Shared Resource, Vanderbilt University, Nashville, Tennessee
| | - Amy C Engevik
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
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11
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Rathan-Kumar S, Roland JT, Momoh M, Goldstein A, Lapierre LA, Manning E, Mitchell L, Norman J, Kaji I, Goldenring JR. Rab11FIP1-deficient mice develop spontaneous inflammation and show increased susceptibility to colon damage. Am J Physiol Gastrointest Liver Physiol 2022; 323:G239-G254. [PMID: 35819177 PMCID: PMC9423785 DOI: 10.1152/ajpgi.00042.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 06/23/2022] [Accepted: 06/29/2022] [Indexed: 01/31/2023]
Abstract
The small GTPase, Rab11a, regulates vesicle trafficking and cell polarity in epithelial cells through interaction with Rab11 family-interacting proteins (Rab11-FIPs). We hypothesized that deficiency of Rab11-FIP1 would affect mucosal integrity in the intestine. Global Rab11FIP1 knockout (KO) mice were generated by deletion of the second exon. Pathology of intestinal tissues was analyzed by immunostaining of colonic sections and RNA-sequencing of isolated colonic epithelial cells. A low concentration of dextran sodium sulfate (DSS, 2%) was added to drinking water for 5 days, and injury score was compared between Rab11FIP1 KO, Rab11FIP2 KO, and heterozygous littermates. Rab11FIP1 KO mice showed normal fertility and body weight gain. More frequent lymphoid patches and infiltration of macrophages and neutrophils were identified in Rab11FIP1 KO mice before the development of rectal prolapse compared with control mice. The population of trefoil factor 3 (TFF3)-positive goblet cells was significantly lower, and the ratio of proliferative to nonproliferative cells was higher in Rab11FIP1 KO colons. Transcription signatures indicated that Rab11FIP1 deletion downregulated genes that mediate stress tolerance response, whereas genes mediating the response to infection were significantly upregulated, consistent with the inflammatory responses in the steady state. Lack of Rab11FIP1 also resulted in abnormal accumulation of subapical vesicles in colonocytes and the internalization of transmembrane mucin, MUC13, with Rab14. After DSS treatment, Rab11FIP1 KO mice showed greater body weight loss and more severe mucosal damage than those in heterozygous littermates. These findings suggest that Rab11FIP1 is important for cytoprotection mechanisms and for the maintenance of colonic mucosal integrity.NEW & NOTEWORTHY Although Rab11FIP1 is important in membrane trafficking in epithelial cells, the gastrointestinal phenotype of Rab11FIP1 knockout (KO) mice had never been reported. This study demonstrated that Rab11FIP1 loss induces mistrafficking of Rab14 and MUC13 and decreases in colonic goblet cells, resulting in impaired mucosal integrity.
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Affiliation(s)
- Sudiksha Rathan-Kumar
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Joseph T Roland
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Michael Momoh
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Anna Goldstein
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Lynne A Lapierre
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Elizabeth Manning
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Louise Mitchell
- Cancer Research UK Beatson Institute, Glasgow, Scotland, United Kingdom
| | - Jim Norman
- Cancer Research UK Beatson Institute, Glasgow, Scotland, United Kingdom
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - James R Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
- Nashville Veterans Affairs Medical Center, Nashville, Tennessee
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12
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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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13
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Ahsan MK, dos Reis DC, Barbieri A, Sumigray KD, Nottoli T, Salas PJ, Ameen NA. Loss of Serum Glucocorticoid-Inducible Kinase 1 SGK1 Worsens Malabsorption and Diarrhea in Microvillus Inclusion Disease (MVID). J Clin Med 2022; 11:jcm11144179. [PMID: 35887942 PMCID: PMC9319011 DOI: 10.3390/jcm11144179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/12/2022] [Accepted: 07/14/2022] [Indexed: 11/16/2022] Open
Abstract
Microvillus inclusion disease (MVID), a lethal congenital diarrheal disease, results from loss of function mutations in the apical actin motor myosin VB (MYO5B). How loss of MYO5B leads to both malabsorption and fluid secretion is not well understood. Serum glucocorticoid-inducible kinase 1 (SGK1) regulates intestinal carbohydrate and ion transporters including cystic fibrosis transmembrane conductance regulator (CFTR). We hypothesized that loss of SGK1 could reduce CFTR fluid secretion and MVID diarrhea. Using CRISPR-Cas9 approaches, we generated R26CreER;MYO5Bf/f conditional single knockout (cMYO5BKO) and R26CreER;MYO5Bf/f;SGK1f/f double knockout (cSGK1/MYO5B-DKO) mice. Tamoxifen-treated cMYO5BKO mice resulted in characteristic features of human MVID including severe diarrhea, microvillus inclusions (MIs) in enterocytes, defective apical traffic, and depolarization of transporters. However, apical CFTR distribution was preserved in crypts and depolarized in villus enterocytes, and CFTR high expresser (CHE) cells were observed. cMYO5BKO mice displayed increased phosphorylation of SGK1, PDK1, and the PDK1 target PKCι in the intestine. Surprisingly, tamoxifen-treated cSGK1/MYO5B-DKO mice displayed more severe diarrhea than cMYO5BKO, with preservation of apical CFTR and CHE cells, greater fecal glucose and reduced SGLT1 and GLUT2 in the intestine. We conclude that loss of SGK1 worsens carbohydrate malabsorption and diarrhea in MVID.
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Affiliation(s)
- Md Kaimul Ahsan
- Department of Pediatrics, Gastroenterology and Hepatology, Yale University School of Medicine, New Haven, CT 06510, USA; (M.K.A.); (D.C.d.R.)
| | - Diego Carlos dos Reis
- Department of Pediatrics, Gastroenterology and Hepatology, Yale University School of Medicine, New Haven, CT 06510, USA; (M.K.A.); (D.C.d.R.)
| | - Andrea Barbieri
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA;
| | - Kaelyn D. Sumigray
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06510, USA;
| | - Timothy Nottoli
- Genome Editing Center, Comparative Medicine, Yale University School of Medicine, New Haven, CT 06510, USA;
| | - Pedro J. Salas
- Department of Cell Biology, Miller School of Medicine, University of Miami, Miami, FL 33146, USA;
| | - Nadia A. Ameen
- Department of Pediatrics, Gastroenterology and Hepatology, Yale University School of Medicine, New Haven, CT 06510, USA; (M.K.A.); (D.C.d.R.)
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA
- Correspondence:
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14
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Bowman DM, Kaji I, Goldenring JR. Altered MYO5B Function Underlies Microvillus Inclusion Disease: Opportunities for Intervention at a Cellular Level. Cell Mol Gastroenterol Hepatol 2022; 14:553-565. [PMID: 35660026 PMCID: PMC9304615 DOI: 10.1016/j.jcmgh.2022.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/31/2022] [Accepted: 04/29/2022] [Indexed: 12/10/2022]
Abstract
Microvillus inclusion disease (MVID) is a congenital diarrheal disorder resulting in life-threatening secretory diarrhea in newborns. Inactivating and nonsense mutations in myosin Vb (MYO5B) have been identified in MVID patients. Work using patient tissues, cell lines, mice, and pigs has led to critical insights into the pathology of MVID and a better understanding of both apical trafficking in intestinal enterocytes and intestinal stem cell differentiation. These studies have demonstrated that loss of MYO5B or inactivating mutations lead to loss of apical sodium and water transporters, without loss of apical CFTR, accounting for the major pathology of the disease. In addition, loss of MYO5B expression induces the formation of microvillus inclusions through apical bulk endocytosis that utilizes dynamin and PACSIN2 and recruits tight junction proteins to the sites of bulk endosome formation. Importantly, formation of microvillus inclusions is not required for the induction of diarrhea. Recent investigations have demonstrated that administration of lysophosphatidic acid (LPA) can partially reestablish apical ion transporters in enterocytes of MYO5B KO mice. In addition, further studies have shown that MYO5B loss induces an imbalance in Wnt/Notch signaling pathways that can lead to alterations in enterocyte maturation and tuft cell lineage differentiation. Inhibition of Notch signaling leads to improvements in those cell differentiation deficits. These studies demonstrate that directed strategies through LPA receptor activation and Notch inhibition can bypass the inhibitory effects of MYO5B loss. Thus, effective strategies may be successful in MVID patients and other congenital diarrhea syndromes to reestablish proper apical membrane absorption of sodium and water in enterocytes and ameliorate life-threatening congenital diarrhea.
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Affiliation(s)
- Deanna M Bowman
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.
| | - James R Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Nashville VA Medical Center, Nashville, Tennessee.
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15
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Zheng Y, Peng Y, Zhang S, Zhao H, Chen W, Yang Y, Hu Z, Yin Q, Peng Y. Case Report: MYO5B Homozygous Variant c.2090+3A>T Causes Intron Retention Related to Chronic Cholestasis and Diarrhea. Front Genet 2022; 13:872836. [PMID: 35706451 PMCID: PMC9189387 DOI: 10.3389/fgene.2022.872836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/15/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Biallelically mutated MYO5B is associated with microvillus inclusion disease (MVID, MIM: 251850), cholestasis, or both. This study aims at validating the splicing alteration and clinical features of an intron variant for diagnosis.Case Presentation: A homozygous variant of MYO5B, NM_001080467.2:c.2090+3A > T (NP_001073936.1:p.?) in intron 17, was identified in a patient suffering from chronic cholestasis and diarrhea. Functional validation showed that this variant caused 185 bp of intron retention in its mRNA and was predicted to present a premature translation termination site for myoVb (p.Arg697fs*47) in the head motor domain. In addition, bowel biopsy revealed decreased microvilli and local lesions of microvillus inclusion in the duodena of the patient. The patient was presented with neonatal cholestasis leading to cirrhosis, intractable diarrhea, cholelithiasis, hepatic cyst, corneal opacity, and failure to thrive.Conclusion: Our study demonstrated an intronic homozygous variant of MYO5B that affected an intron, subsequently altering splicing and leading to combined cholestasis and MVID. Our results further supported the underlying genotype–phenotype correlations and extended clinical practices toward its diagnosis and management.
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Affiliation(s)
- Yu Zheng
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
| | - Yuming Peng
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
| | - Shuju Zhang
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
| | - Hongmei Zhao
- Department of Gastroenterology and Nutrition, Hunan Children’s Hospital, Changsha, China
| | - Weijian Chen
- Department of Pathology, Hunan Children’s Hospital, Changsha, China
| | - Yongjia Yang
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
| | - Zhengmao Hu
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, China
| | - Qiang Yin
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
- *Correspondence: Qiang Yin, ; Yu Peng,
| | - Yu Peng
- First Department of General Surgery & Pediatrics Research Institute of Hunan Province, Hunan Children’s Hospital, Changsha, China
- *Correspondence: Qiang Yin, ; Yu Peng,
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16
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Kaji I, Roland JT, Rathan-Kumar S, Engevik AC, Burman A, Goldstein AE, Watanabe M, Goldenring JR. Cell differentiation is disrupted by MYO5B loss through Wnt/Notch imbalance. JCI Insight 2021; 6:e150416. [PMID: 34197342 PMCID: PMC8409988 DOI: 10.1172/jci.insight.150416] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/30/2021] [Indexed: 11/17/2022] Open
Abstract
Functional loss of myosin Vb (MYO5B) induces a variety of deficits in intestinal epithelial cell function and causes a congenital diarrheal disorder, microvillus inclusion disease (MVID). The impact of MYO5B loss on differentiated cell lineage choice has not been investigated. We quantified the populations of differentiated epithelial cells in tamoxifen-induced, epithelial cell–specific MYO5B-knockout (VilCreERT2 Myo5bfl/fl) mice utilizing digital image analysis. Consistent with our RNA-sequencing data, MYO5B loss induced a reduction in tuft cells in vivo and in organoid cultures. Paneth cells were significantly increased by MYO5B deficiency along with expansion of the progenitor cell zone. We further investigated the effect of lysophosphatidic acid (LPA) signaling on epithelial cell differentiation. Intraperitoneal LPA significantly increased tuft cell populations in both control and MYO5B-knockout mice. Transcripts for Wnt ligands were significantly downregulated by MYO5B loss in intestinal epithelial cells, whereas Notch signaling molecules were unchanged. Additionally, treatment with the Notch inhibitor dibenzazepine (DBZ) restored the populations of secretory cells, suggesting that the Notch pathway is maintained in MYO5B-deficient intestine. MYO5B loss likely impairs progenitor cell differentiation in the small intestine in vivo and in vitro, partially mediated by Wnt/Notch imbalance. Notch inhibition and/or LPA treatment may represent an effective therapeutic approach for treatment of MVID.
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Affiliation(s)
- Izumi Kaji
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Joseph T Roland
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sudiksha Rathan-Kumar
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Amy C Engevik
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Andreanna Burman
- Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Anna E Goldstein
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Masahiko Watanabe
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Sapporo, Japan
| | - James R Goldenring
- Section of Surgical Sciences and.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Nashville VA Medical Center, Nashville, Tennessee, USA
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17
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Pierreux CE. Shaping the thyroid: From peninsula to de novo lumen formation. Mol Cell Endocrinol 2021; 531:111313. [PMID: 33961919 DOI: 10.1016/j.mce.2021.111313] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 01/06/2023]
Abstract
A challenging and stimulating question in biology deals with the formation of organs from groups of undifferentiated progenitor cells. Most epithelial organs indeed derive from the endodermal monolayer and evolve into various shape and tridimensional organization adapted to their specialized adult function. Thyroid organogenesis is no exception. In most mammals, it follows a complex and sequential process initiated from the endoderm and leading to the development of a multitude of independent closed spheres equipped and optimized for the synthesis, storage and production of thyroid hormones. The first sign of thyroid organogenesis is visible as a thickening of the anterior foregut endoderm. This group of thyroid progenitors then buds and detaches from the foregut to migrate caudally and then laterally. Upon reaching their final destination in the upper neck region on both sides of the trachea, thyroid progenitors mix with C cell progenitors and finally organize into hormone-producing thyroid follicles. Intrinsic and extrinsic factors controlling thyroid organogenesis have been identified in several species, but the fundamental cellular processes are not sufficiently considered. This review focuses on the cellular aspects of the key morphogenetic steps during thyroid organogenesis and highlights similarities and common mechanisms with developmental steps elucidated in other endoderm-derived organs, despite different final architecture and functions.
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18
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Advanced Microscopy for Liver and Gut Ultrastructural Pathology in Patients with MVID and PFIC Caused by MYO5B Mutations. J Clin Med 2021; 10:jcm10091901. [PMID: 33924896 PMCID: PMC8125609 DOI: 10.3390/jcm10091901] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
Mutations in the actin motor protein myosinVb (myo5b) cause aberrant apical cargo transport and the congenital enteropathy microvillus inclusion disease (MVID). Recently, missense mutations in myo5b were also associated with progressive familial intrahepatic cholestasis (MYO5B-PFIC). Here, we thoroughly characterized the ultrastructural and immuno-cytochemical phenotype of hepatocytes and duodenal enterocytes from a unique case of an adult MYO5B-PFIC patient who showed constant hepatopathy but only periodic enteric symptoms. Selected data from two other patients supported the findings. Advanced methods such as cryo-fixation, freeze-substitution, immuno-gold labeling, electron tomography and immuno-fluorescence microscopy complemented the standard procedures. Liver biopsies showed mislocalization of Rab11 and bile canalicular membrane proteins. Rab11-positive vesicles clustered around bile canaliculi and resembled subapical clusters of aberrant recycling endosomes in enterocytes from MVID patients. The adult patient studied in detail showed a severe, MVID-specific enterocyte phenotype, despite only a mild clinical intestinal presentation. This included mislocalization of numerous proteins essential for apical cargo transport and morphological alterations. We characterized the heterogeneous population of large catabolic organelles regarding their complex ultrastructure and differential distribution of autophagic and lysosomal marker proteins. Finally, we generated duodenal organoids/enteroids from biopsies that recapitulated all MVID hallmarks, demonstrating the potential of this disease model for personalized medicine.
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19
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Myosin Motors: Novel Regulators and Therapeutic Targets in Colorectal Cancer. Cancers (Basel) 2021; 13:cancers13040741. [PMID: 33670106 PMCID: PMC7916823 DOI: 10.3390/cancers13040741] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/06/2021] [Accepted: 02/08/2021] [Indexed: 12/11/2022] Open
Abstract
Simple Summary Colorectal cancer (CRC) is a deadly disease that may go undiagnosed until it presents at an advanced metastatic stage for which few interventions are available. The development and metastatic spread of CRC is driven by remodeling of the actin cytoskeleton in cancer cells. Myosins represent a large family of actin motor proteins that play key roles in regulating actin cytoskeleton architecture and dynamics. Different myosins can move and cross-link actin filaments, attach them to the membrane organelles and translocate vesicles along the actin filaments. These diverse activities determine the key roles of myosins in regulating cell proliferation, differentiation and motility. Either mutations or the altered expression of different myosins have been well-documented in CRC; however, the roles of these actin motors in colon cancer development remain poorly understood. The present review aims at summarizing the evidence that implicate myosin motors in regulating CRC growth and metastasis and discusses the mechanisms underlying the oncogenic and tumor-suppressing activities of myosins. Abstract Colorectal cancer (CRC) remains the third most common cause of cancer and the second most common cause of cancer deaths worldwide. Clinicians are largely faced with advanced and metastatic disease for which few interventions are available. One poorly understood aspect of CRC involves altered organization of the actin cytoskeleton, especially at the metastatic stage of the disease. Myosin motors are crucial regulators of actin cytoskeletal architecture and remodeling. They act as mechanosensors of the tumor environments and control key cellular processes linked to oncogenesis, including cell division, extracellular matrix adhesion and tissue invasion. Different myosins play either oncogenic or tumor suppressor roles in breast, lung and prostate cancer; however, little is known about their functions in CRC. This review focuses on the functional roles of myosins in colon cancer development. We discuss the most studied class of myosins, class II (conventional) myosins, as well as several classes (I, V, VI, X and XVIII) of unconventional myosins that have been linked to CRC development. Altered expression and mutations of these motors in clinical tumor samples and their roles in CRC growth and metastasis are described. We also evaluate the potential of using small molecular modulators of myosin activity to develop novel anticancer therapies.
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Redhai S, Boutros M. The Role of Organelles in Intestinal Function, Physiology, and Disease. Trends Cell Biol 2021; 31:485-499. [PMID: 33551307 DOI: 10.1016/j.tcb.2021.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/04/2021] [Accepted: 01/11/2021] [Indexed: 02/06/2023]
Abstract
The intestine maintains homeostasis by coordinating internal biological processes to adjust to fluctuating external conditions. The intestinal epithelium is continuously renewed and comprises multiple cell types, including absorptive cells, secretory cells, and resident stem cells. An important feature of this organ is its ability to coordinate many processes including cell proliferation, differentiation, regeneration, damage/stress response, immune activity, feeding behavior, and age-related changes by using conserved signaling pathways. However, the subcellular spatial organization of these signaling events and the organelles involved has only recently been studied in detail. Here we discuss how organelles of intestinal cells serve to initiate, mediate, and terminate signals, that are vital for homeostasis.
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Affiliation(s)
- Siamak Redhai
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics, and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120 Heidelberg, Germany.
| | - Michael Boutros
- German Cancer Research Center (DKFZ), Division Signaling and Functional Genomics, and Heidelberg University, BioQuant and Medical Faculty Mannheim, D-69120 Heidelberg, Germany.
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21
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Congenital Diarrhea and Cholestatic Liver Disease: Phenotypic Spectrum Associated with MYO5B Mutations. J Clin Med 2021; 10:jcm10030481. [PMID: 33525641 PMCID: PMC7865828 DOI: 10.3390/jcm10030481] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 12/14/2022] Open
Abstract
Myosin Vb (MYO5B) is a motor protein that facilitates protein trafficking and recycling in polarized cells by RAB11- and RAB8-dependent mechanisms. Biallelic MYO5B mutations are identified in the majority of patients with microvillus inclusion disease (MVID). MVID is an intractable diarrhea of infantile onset with characteristic histopathologic findings that requires life-long parenteral nutrition or intestinal transplantation. A large number of such patients eventually develop cholestatic liver disease. Bi-allelic MYO5B mutations are also identified in a subset of patients with predominant early-onset cholestatic liver disease. We present here the compilation of 114 patients with disease-causing MYO5B genotypes, including 44 novel patients as well as 35 novel MYO5B mutations, and an analysis of MYO5B mutations with regard to functional consequences. Our data support the concept that (1) a complete lack of MYO5B protein or early MYO5B truncation causes predominant intestinal disease (MYO5B-MVID), (2) the expression of full-length mutant MYO5B proteins with residual function causes predominant cholestatic liver disease (MYO5B-PFIC), and (3) the expression of mutant MYO5B proteins without residual function causes both intestinal and hepatic disease (MYO5B-MIXED). Genotype-phenotype data are deposited in the existing open MYO5B database in order to improve disease diagnosis, prognosis, and genetic counseling.
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22
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Madrid RR, Mathews PD, Patta AC, Gonzales-Flores AP, Ramirez CA, Rigoni VL, Tavares-Dias M, Mertins O. Safety of oral administration of high doses of ivermectin by means of biocompatible polyelectrolytes formulation. Heliyon 2020; 7:e05820. [PMID: 33426351 PMCID: PMC7775035 DOI: 10.1016/j.heliyon.2020.e05820] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/02/2020] [Accepted: 12/18/2020] [Indexed: 12/23/2022] Open
Abstract
The FDA-approved drug ivermectin is applied for treatments of onchocerciasis and lymphatic filariasis. The anti-cancer and anti-viral activities have been demonstrated stressing possibilities for the drug repurposing and therefore new information on high dosage safety is on demand. We analyzed in vivo tissue responses for high doses of ivermectin using Corydoras fish as animal model. We made intestinal histology and hematologic assays after oral administration of ivermectin transported with polyelectrolytes formulation. Histology showed any apparent damage of intestinal tissues at 0.22–170 mg of ivermectin/kg body weight. Immunofluorescence evidenced delocalization of Myosin-Vb at enterocytes only for the higher dose. Hematology parameters showed random variations after 7 days from administration, but a later apparent recover after 14 and 21 days. The study evaluated the potential of high doses of oral administration of ivermectin formulation, which could be an alternative with benefits in high compliance therapies.
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Affiliation(s)
- Rafael R.M. Madrid
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
| | - Patrick D. Mathews
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
- Corresponding author.
| | - Ana C.M.F. Patta
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
| | - Anai P. Gonzales-Flores
- Post-Graduate Program in Tropical Biodiversity, Federal University of Amapá, 68903-419 Macapá, AP, Brazil
- Institute of Research of the Peruvian Amazon (IIAP, AQUAREC), 17000 Puerto Maldonado, Peru
| | - Carlos A.B. Ramirez
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
| | - Vera L.S. Rigoni
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
| | | | - Omar Mertins
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, SP, Brazil
- Corresponding author.
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van Rijn JM, Werner L, Aydemir Y, Spronck JM, Pode-Shakked B, van Hoesel M, Shimshoni E, Polak-Charcon S, Talmi L, Eren M, Weiss B, H.J. Houwen R, Barshack I, Somech R, Nieuwenhuis EE, Sagi I, Raas-Rothschild A, Middendorp S, Shouval DS. Enhanced Collagen Deposition in the Duodenum of Patients with Hyaline Fibromatosis Syndrome and Protein Losing Enteropathy. Int J Mol Sci 2020; 21:E8200. [PMID: 33147779 PMCID: PMC7662532 DOI: 10.3390/ijms21218200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 12/25/2022] Open
Abstract
Hyaline fibromatosis syndrome (HFS), resulting from ANTXR2 mutations, is an ultra-rare disease that causes intestinal lymphangiectasia and protein-losing enteropathy (PLE). The mechanisms leading to the gastrointestinal phenotype in these patients are not well defined. We present two patients with congenital diarrhea, severe PLE and unique clinical features resulting from deleterious ANTXR2 mutations. Intestinal organoids were generated from one of the patients, along with CRISPR-Cas9 ANTXR2 knockout, and compared with organoids from two healthy controls. The ANTXR2-deficient organoids displayed normal growth and polarity, compared to controls. Using an anthrax-toxin assay we showed that the c.155C>T mutation causes loss-of-function of ANTXR2 protein. An intrinsic defect of monolayer formation in patient-derived or ANTXR2KO organoids was not apparent, suggesting normal epithelial function. However, electron microscopy and second harmonic generation imaging showed abnormal collagen deposition in duodenal samples of these patients. Specifically, collagen VI, which is known to bind ANTXR2, was highly expressed in the duodenum of these patients. In conclusion, despite resistance to anthrax-toxin, epithelial cell function, and specifically monolayer formation, is intact in patients with HFS. Nevertheless, loss of ANTXR2-mediated signaling leads to collagen VI accumulation in the duodenum and abnormal extracellular matrix composition, which likely plays a role in development of PLE.
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Affiliation(s)
- Jorik M. van Rijn
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
- Regenerative Medicine Center, UMCU, UU, 3584 CT Utrecht, The Netherlands
| | - Lael Werner
- Pediatric Gastroenterology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel; (L.W.); (B.W.)
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
| | - Yusuf Aydemir
- Department of Pediatrics, Division of Pediatric Gastroenterology and Hepatology, Eskisehir Osmangazi University Faculty of Medicine, Eskisehir 26040, Turkey; (Y.A.); (M.E.)
| | - Joey M.A. Spronck
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
- Regenerative Medicine Center, UMCU, UU, 3584 CT Utrecht, The Netherlands
| | - Ben Pode-Shakked
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- The Institute for Rare Diseases, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
- Talpiot Medical Leadership Program, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Marliek van Hoesel
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
- Regenerative Medicine Center, UMCU, UU, 3584 CT Utrecht, The Netherlands
| | - Elee Shimshoni
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 7610001, Israel; (E.S.); (I.S.)
| | - Sylvie Polak-Charcon
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- Institute of Pathology, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Liron Talmi
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- Pediatric Department A, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Makbule Eren
- Department of Pediatrics, Division of Pediatric Gastroenterology and Hepatology, Eskisehir Osmangazi University Faculty of Medicine, Eskisehir 26040, Turkey; (Y.A.); (M.E.)
| | - Batia Weiss
- Pediatric Gastroenterology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel; (L.W.); (B.W.)
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
| | - Roderick H.J. Houwen
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
| | - Iris Barshack
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- Institute of Pathology, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Raz Somech
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- Pediatric Department A, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
- Immunology Service, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
- Jeffrey Modell Foundation Center, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Edward E.S. Nieuwenhuis
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
| | - Irit Sagi
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 7610001, Israel; (E.S.); (I.S.)
| | - Annick Raas-Rothschild
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
- The Institute for Rare Diseases, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel
| | - Sabine Middendorp
- Division of Pediatrics, Department of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht (UMCU), Utrecht University (UU), 3584 CT Utrecht, The Netherlands; (J.M.v.R.); (J.M.A.S.); (M.v.H.); (R.H.J.H.); (E.E.S.N.)
- Regenerative Medicine Center, UMCU, UU, 3584 CT Utrecht, The Netherlands
| | - Dror S. Shouval
- Pediatric Gastroenterology Unit, Edmond and Lily Safra Children’s Hospital, Sheba Medical Center, Ramat Gan 5262100, Israel; (L.W.); (B.W.)
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 6997801, Israel; (B.P.-S.); (S.P.-C.); (L.T.); (I.B.); (R.S.); (A.R.-R.)
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Abstract
Actin is a conserved cytoskeletal protein with essential functions. Here, we review the state-of-the-art reagents, tools and methods used to probe actin biology and functions in zebrafish embryo and larvae. We also discuss specific cell types and tissues where the study of actin in zebrafish has provided new insights into its functions.
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25
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Kaji I, Roland JT, Watanabe M, Engevik AC, Goldstein AE, Hodges CA, Goldenring JR. Lysophosphatidic Acid Increases Maturation of Brush Borders and SGLT1 Activity in MYO5B-deficient Mice, a Model of Microvillus Inclusion Disease. Gastroenterology 2020; 159:1390-1405.e20. [PMID: 32534933 PMCID: PMC8240502 DOI: 10.1053/j.gastro.2020.06.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIM Myosin VB (MYO5B) is an essential trafficking protein for membrane recycling in gastrointestinal epithelial cells. The inactivating mutations of MYO5B cause the congenital diarrheal disease, microvillus inclusion disease (MVID). MYO5B deficiency in mice causes mislocalization of SGLT1 and NHE3, but retained apical function of CFTR, resulting in malabsorption and secretory diarrhea. Activation of lysophosphatidic acid (LPA) receptors can improve diarrhea, but the effect of LPA on MVID symptoms is unclear. We investigated whether LPA administration can reduce the epithelial deficits in MYO5B-knockout mice. METHODS Studies were conducted with tamoxifen-induced, intestine-specific knockout of MYO5B (VilCreERT2;Myo5bflox/flox) and littermate controls. Mice were given LPA, an LPAR2 agonist (GRI977143), or vehicle for 4 days after a single injection of tamoxifen. Apical SGLT1 and CFTR activities were measured in Üssing chambers. Intestinal tissues were collected, and localization of membrane transporters was evaluated by immunofluorescence analysis in tissue sections and enteroids. RNA sequencing and enrichment analysis were performed with isolated jejunal epithelial cells. RESULTS Daily administration of LPA reduced villus blunting, frequency of multivesicular bodies, and levels of cathepsins in intestinal tissues of MYO5B-knockout mice compared with vehicle administration. LPA partially restored the brush border height and the localization of SGLT1 and NHE3 in small intestine of MYO5B-knockout mice and enteroids. The SGLT1-dependent short-circuit current was increased and abnormal CFTR activities were decreased in jejunum from MYO5B-knockout mice given LPA compared with vehicle. CONCLUSIONS LPA may regulate a MYO5B-independent trafficking mechanism and brush border maturation, and therefore be developed for treatment of MVID.
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Affiliation(s)
- Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.
| | - Joseph T. Roland
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | | | - Amy C. Engevik
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Anna E. Goldstein
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan
| | - Craig A. Hodges
- Cystic Fibrosis Mouse Models Resource Center, Case Western Reserve University, Cleveland, OH
| | - James R. Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Sapporo, Japan,Epithelial Biology Center, Vanderbilt University School of Medicine, Sapporo, Japan,Cell and Developmental Biology, Vanderbilt University School of Medicine, Sapporo, Japan,Nashville Veterans Affairs Medical Center, Nashville TN
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26
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Badawy A, Elfadul M, Aziabi M, Ageel HI, Aqeel A. Challenges of Microvillus Inclusion Disease in the NICU. Neoreviews 2020; 21:e600-e604. [PMID: 32873653 DOI: 10.1542/neo.21-9-e600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Mutations in the myosin 5β, syntaxin-binding protein 2, and syntaxin 3 genes lead to microvillus inclusion disease (MVID), an autosomal recessive congenital enteropathy. This rare disease is characterized by lack of microvilli on the surface of enterocytes in the small intestine, the presence of pathognomonic intracellular microvillus inclusions, and vesicular bodies within these enterocytes. This pathology leads to the characteristic intractable, life-threatening, watery diarrhea. In the more common early-onset form, affected patients present in the first few days after birth, whereas in the late-onset form, clinical manifestations appear at approximately 2 to 3 months of age. Genetic testing can confirm the diagnosis, but the infant's medical history, clinical presentation, and small intestinal biopsy results are strongly suggestive of the diagnosis. The prevalence of MVID is thought to be higher in countries with a high degree of consanguinity. Patients with MVID cannot tolerate feedings and require continuous total parenteral nutrition. Mortality is extremely high in the early-onset type with reports of survival in patients treated with small intestinal transplantation. Medical counseling for parents of infants with MVID needs to reflect our current understanding of the various genetic forms of this disease, the feasible management, and anticipated outcomes.
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Affiliation(s)
| | | | | | - Hossain Ibrahim Ageel
- Gastroenterology Unit, Pediatrics Department, King Fahd Central Hospital, Gazan, Saudi Arabia
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27
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Abstract
Myosins constitute a superfamily of actin-based molecular motor proteins that mediates a variety of cellular activities including muscle contraction, cell migration, intracellular transport, the formation of membrane projections, cell adhesion, and cell signaling. The 12 myosin classes that are expressed in humans share sequence similarities especially in the N-terminal motor domain; however, their enzymatic activities, regulation, ability to dimerize, binding partners, and cellular functions differ. It is becoming increasingly apparent that defects in myosins are associated with diseases including cardiomyopathies, colitis, glomerulosclerosis, neurological defects, cancer, blindness, and deafness. Here, we review the current state of knowledge regarding myosins and disease.
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28
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Iwaki A, Moriwaki K, Sobajima T, Taniguchi M, Yoshimura SI, Kunii M, Kanda S, Kamada Y, Miyoshi E, Harada A. Loss of Rab6a in the small intestine causes lipid accumulation and epithelial cell death from lactation. FASEB J 2020; 34:9450-9465. [PMID: 32496646 DOI: 10.1096/fj.202000028r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 04/24/2020] [Accepted: 05/05/2020] [Indexed: 11/11/2022]
Abstract
Intestinal epithelial cells (IECs) are not only responsible for the digestion and absorption of dietary substrates but also function as a first line of host defense against commensal and pathogenic luminal bacteria. Disruption of the epithelial layer causes malnutrition and enteritis. Rab6 is a small GTPase localized to the Golgi, where it regulates anterograde and retrograde transport by interacting with various effector proteins. Here, we generated mice with IEC-specific deletion of Rab6a (Rab6a∆IEC mice). While Rab6aΔIEC mice were born at the Mendelian ratio, they started to show IEC death, inflammation, and bleeding in the small intestine shortly after birth, and these changes culminated in early postnatal death. We further found massive lipid accumulation in the IECs of Rab6a∆IEC neonates. In contrast to Rab6a∆IEC neonates, knockout embryos did not show any of these abnormalities. Lipid accumulation and IEC death became evident when Rab6a∆IEC embryos were nursed by a foster mother, suggesting that dietary milk-derived lipids accumulated in Rab6a-deficient IECs and triggered IEC death. These results indicate that Rab6a plays a crucial role in regulating the lipid transport and maintaining tissue integrity.
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Affiliation(s)
- Ayano Iwaki
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan.,Department of Molecular Biochemistry and Clinical Investigation, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Kenta Moriwaki
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Tomoaki Sobajima
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan.,Department of Molecular Biochemistry and Clinical Investigation, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Manabu Taniguchi
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Shin-Ichiro Yoshimura
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Masataka Kunii
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Satoshi Kanda
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Yoshihiro Kamada
- Department of Molecular Biochemistry and Clinical Investigation, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Eiji Miyoshi
- Department of Molecular Biochemistry and Clinical Investigation, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Akihiro Harada
- Department of Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
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29
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Engevik AC, Coutts AW, Kaji I, Rodriguez P, Ongaratto F, Saqui-Salces M, Medida RL, Meyer AR, Kolobova E, Engevik MA, Williams JA, Shub MD, Carlson DF, Melkamu T, Goldenring JR. Editing Myosin VB Gene to Create Porcine Model of Microvillus Inclusion Disease, With Microvillus-Lined Inclusions and Alterations in Sodium Transporters. Gastroenterology 2020; 158:2236-2249.e9. [PMID: 32112796 PMCID: PMC7282982 DOI: 10.1053/j.gastro.2020.02.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/07/2020] [Accepted: 02/17/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND & AIMS Microvillus inclusion disease (MVID) is caused by inactivating mutations in the myosin VB gene (MYO5B). MVID is a complex disorder characterized by chronic, watery, life-threatening diarrhea that usually begins in the first hours to days of life. We developed a large animal model of MVID to better understand its pathophysiology. METHODS Pigs were cloned by transfer of chromatin from swine primary fetal fibroblasts, which were edited with TALENs and single-strand oligonucleotide to introduce a P663-L663 substitution in the endogenous swine MYO5B (corresponding to the P660L mutation in human MYO5B, associated with MVID) to fertilized oocytes. We analyzed duodenal tissues from patients with MVID (with the MYO5B P660L mutation) and without (controls), and from pigs using immunohistochemistry. Enteroids were generated from pigs with MYO5B(P663L) and without the substitution (control pigs). RESULTS Duodenal tissues from patients with MVID lacked MYO5B at the base of the apical membrane of intestinal cells; instead MYO5B was intracellular. Intestinal tissues and derived enteroids from MYO5B(P663L) piglets had reduced apical levels and diffuse subapical levels of sodium hydrogen exchanger 3 and SGLT1, which regulate transport of sodium, glucose, and water, compared with tissues from control piglets. However, intestinal tissues and derived enteroids from MYO5B(P663L) piglets maintained CFTR on apical membranes, like tissues from control pigs. Liver tissues from MYO5B(P663L) piglets had alterations in bile salt export pump, a transporter that facilitates bile flow, which is normally expressed in the bile canaliculi in the liver. CONCLUSIONS We developed a large animal model of MVID that has many features of the human disease. Studies of this model could provide information about the functions of MYO5B and MVID pathogenesis, and might lead to new treatments.
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Affiliation(s)
- Amy C Engevik
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.
| | | | - Izumi Kaji
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | | | | | - Milena Saqui-Salces
- Department of Animal Science, University of Minnesota, Saint Paul, Minnesota
| | - Ramya Lekha Medida
- Department of Animal Science, University of Minnesota, Saint Paul, Minnesota
| | - Anne R Meyer
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Elena Kolobova
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Melinda A Engevik
- Baylor College of Medicine and Texas Children's Hospital, Houston, Texas
| | - Janice A Williams
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Mitchell D Shub
- Phoenix Children's Hospital and University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
| | | | | | - James R Goldenring
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; The Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee; Nashville Veterans Affairs Medical Center, Nashville, Tennessee
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30
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Beneficial Effect of Mildly Pasteurized Whey Protein on Intestinal Integrity and Innate Defense in Preterm and Near-Term Piglets. Nutrients 2020; 12:nu12041125. [PMID: 32316586 PMCID: PMC7230795 DOI: 10.3390/nu12041125] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 02/08/2023] Open
Abstract
Background. The human digestive tract is structurally mature at birth, yet maturation of gut functions such as digestion and mucosal barrier continues for the next 1–2 years. Human milk and infant milk formulas (IMF) seem to impact maturation of these gut functions differently, which is at least partially related to high temperature processing of IMF causing loss of bioactive proteins and formation of advanced glycation end products (AGEs). Both loss of protein bioactivity and formation of AGEs depend on heating temperature and time. The aim of this study was to investigate the impact of mildly pasteurized whey protein concentrate (MP-WPC) compared to extensively heated WPC (EH-WPC) on gut maturation in a piglet model hypersensitive to enteral nutrition. Methods. WPC was obtained by cold filtration and mildly pasteurized (73 °C, 30 s) or extensively heat treated (73 °C, 30 s + 80 °C, 6 min). Preterm (~90% gestation) and near-term piglets (~96% gestation) received enteral nutrition based on MP-WPC or EH-WPC for five days. Macroscopic and histologic lesions in the gastro-intestinal tract were evaluated and intestinal responses were further assessed by RT-qPCR, immunohistochemistry and enzyme activity analysis. Results. A diet based on MP-WPC limited epithelial intestinal damage and improved colonic integrity compared to EH-WPC. MP-WPC dampened colonic IL1-β, IL-8 and TNF-α expression and lowered T-cell influx in both preterm and near-term piglets. Anti-microbial defense as measured by neutrophil influx in the colon was only observed in near-term piglets, correlated with histological damage and was reduced by MP-WPC. Moreover, MP-WPC stimulated iALP activity in the colonic epithelium and increased differentiation into enteroendocrine cells compared to EH-WPC. Conclusions. Compared to extensively heated WPC, a formula based on mildly pasteurized WPC limits gut inflammation and stimulates gut maturation in preterm and near-term piglets and might therefore also be beneficial for preterm and (near) term infants.
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31
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Nakamura Y, Ochi Y, Satoh T, Satoh AK. Rab10, Crag and Ehbp1 regulate the basolateral transport of Na +K +ATPase in Drosophila photoreceptors. J Cell Sci 2020; 133:jcs238790. [PMID: 32041903 DOI: 10.1242/jcs.238790] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 01/27/2020] [Indexed: 08/31/2023] Open
Abstract
Cells in situ are often polarized and have multiple plasma membrane domains. To establish and maintain these domains, polarized transport is essential, and its impairment results in genetic disorders. Nevertheless, the underlying mechanisms of polarized transport have not been elucidated. Drosophila photoreceptor offers an excellent model for studying this. We found that Rab10 impairment significantly reduced basolateral levels of Na+K+ATPase, mislocalizing it to the stalk membrane, which is a domain of the apical plasma membrane. Furthermore, the shrunken basolateral and the expanded stalk membranes were accompanied with abnormalities in the Golgi cisternae of Rab10-impaired retinas. The deficiencies of Rab10-GEF Crag or the Rab10 effector Ehbp1 phenocopied Rab10 deficiency, indicating that Crag, Rab10 and Ehbp1 work together for polarized trafficking of membrane proteins to the basolateral membrane. These phenotypes were similar to those seen upon deficiency of AP1 or clathrin, which are known to be involved in the basolateral transport in other systems. Additionally, Crag, Rab10 and Ehbp1 colocalized with AP1 and clathrin on the trans-side of Golgi stacks. Taken together, these results indicate that AP1 and clathrin, and Crag, Rab10 and Ehbp1 collaborate in polarized basolateral transport, presumably in the budding process in the trans-Golgi network.
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Affiliation(s)
- Yuri Nakamura
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Yuka Ochi
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Takunori Satoh
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Akiko K Satoh
- Program of Life and Environmental Science, Graduate School of Integral Science for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan
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32
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Jayawardena D, Alrefai WA, Dudeja PK, Gill RK. Recent advances in understanding and managing malabsorption: focus on microvillus inclusion disease. F1000Res 2019; 8. [PMID: 31824659 PMCID: PMC6896243 DOI: 10.12688/f1000research.20762.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/29/2019] [Indexed: 12/11/2022] Open
Abstract
Microvillus inclusion disease (MVID) is a rare congenital severe malabsorptive and secretory diarrheal disease characterized by blunted or absent microvilli with accumulation of secretory granules and inclusion bodies in enterocytes. The typical clinical presentation of the disease is severe chronic diarrhea that rapidly leads to dehydration and metabolic acidosis. Despite significant advances in our understanding of the causative factors, to date, no curative therapy for MVID and associated diarrhea exists. Prognosis mainly relies on life-long total parenteral nutrition (TPN) and eventual small bowel and/or liver transplantation. Both TPN and intestinal transplantation are challenging and present with many side effects. A breakthrough in the understanding of MVID emanated from seminal findings revealing mutations in
MYO5B as a cause for MVID. During the last decade, many studies have thus utilized cell lines and animal models with knockdown of
MYO5B to closely recapitulate the human disease and investigate potential therapeutic options in disease management. We will review the most recent advances made in the research pertaining to MVID. We will also highlight the tools and models developed that can be utilized for basic and applied research to increase our understanding of MVID and develop novel and effective targeted therapies.
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Affiliation(s)
- Dulari Jayawardena
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Waddah A Alrefai
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA.,Jesse Brown VA Medical Center, Chicago, IL, USA
| | - Pradeep K Dudeja
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA.,Jesse Brown VA Medical Center, Chicago, IL, USA
| | - Ravinder K Gill
- Division of Gastroenterology & Hepatology, University of Illinois at Chicago, Chicago, IL, USA
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Lattner J, Leng W, Knust E, Brankatschk M, Flores-Benitez D. Crumbs organizes the transport machinery by regulating apical levels of PI(4,5)P 2 in Drosophila. eLife 2019; 8:e50900. [PMID: 31697234 PMCID: PMC6881148 DOI: 10.7554/elife.50900] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 10/25/2019] [Indexed: 12/12/2022] Open
Abstract
An efficient vectorial intracellular transport machinery depends on a well-established apico-basal polarity and is a prerequisite for the function of secretory epithelia. Despite extensive knowledge on individual trafficking pathways, little is known about the mechanisms coordinating their temporal and spatial regulation. Here, we report that the polarity protein Crumbs is essential for apical plasma membrane phospholipid-homeostasis and efficient apical secretion. Through recruiting βHeavy-Spectrin and MyosinV to the apical membrane, Crumbs maintains the Rab6-, Rab11- and Rab30-dependent trafficking and regulates the lipid phosphatases Pten and Ocrl. Crumbs knock-down results in increased apical levels of PI(4,5)P2 and formation of a novel, Moesin- and PI(4,5)P2-enriched apical membrane sac containing microvilli-like structures. Our results identify Crumbs as an essential hub required to maintain the organization of the apical membrane and the physiological activity of the larval salivary gland.
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Affiliation(s)
- Johanna Lattner
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Weihua Leng
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Elisabeth Knust
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
| | - Marko Brankatschk
- The Biotechnological Center of the TU Dresden (BIOTEC)DresdenGermany
| | - David Flores-Benitez
- Max-Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG)DresdenGermany
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34
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Goldenring JR. The challenge of personalized cell biology: The example of microvillus inclusion disease. Traffic 2019; 21:169-171. [PMID: 31596022 DOI: 10.1111/tra.12703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 09/28/2019] [Accepted: 09/30/2019] [Indexed: 11/30/2022]
Abstract
Whole exome sequencing now provides a tool for rapid analysis of patients manifesting congenital diseases. Congenital diarrheal diseases provide a critical example of the challenges of combining identification of genetic mutations responsible for disease with characterization of the cell biological and cell physiological deficits observed in patients. Recent studies exploring the cellular events associated with loss of functional Myosin 5B (MYO5B) have demonstrated the importance of cell biological and physiological analyses to provide a greater understanding of the implications of pathological mutations. Development of enteroids derived from biopsies of patients with complex congenital diarrheal diseases provides a critical resource for evaluation of the cell biological impact of specific monogenic mutations on enterocyte function. The ability to identify putative causative mutations for congenital disease now provides an opportunity to coordinate the efforts of physicians and cell biologists in an effort to provide patients with personalized cell biology analysis to improve patient diagnosis and treatment.
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Affiliation(s)
- James R Goldenring
- Department of Surgery and Cell and Developmental Biology, and the Epithelial Biology Center, Vanderbilt University Medical Center, and the Nashville VA Medical Center, Nashville, Tennessee
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35
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Forteza R, Ahsan MK, Cartón-García F, Arango D, Ameen NA, Salas PJ. Glucocorticoids and myosin5b loss of function induce heightened PKA signaling in addition to membrane traffic defects. Mol Biol Cell 2019; 30:3076-3089. [PMID: 31664880 PMCID: PMC6938243 DOI: 10.1091/mbc.e18-07-0415] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Loss-of-function mutations in the nonconventional myosin Vb (Myo5b) result in microvillus inclusion disease (MVID) and massive secretory diarrhea that often begins at birth. Myo5b mutations disrupt the apical recycling endosome (ARE) and membrane traffic, resulting in reduced surface expression of apical membrane proteins. ARE disruption also results in constitutive phosphoinositide-dependent kinase 1 gain of function. In MVID, decreased surface expression of apical anion channels involved in Cl- extrusion, such as cystic fibrosis transmembrane conductance regulator (CFTR), should reduce fluid secretion into the intestinal lumen. But the opposite phenotype is observed. To explain this contradiction and the onset of diarrhea, we hypothesized that signaling effects downstream from Myo5b loss of function synergize with higher levels of glucocorticoids to activate PKA and CFTR. Data from intestinal cell lines, human MVID, and Myo5b KO mouse intestine revealed changes in the subcellular redistribution of PKA activity to the apical pole, increased CFTR phosphorylation, and establishment of apical cAMP gradients in Myo5b-defective cells exposed to physiological levels of glucocorticoids. These cells also displayed net secretory fluid fluxes and transepithelial currents mainly from PKA-dependent Cl- secretion. We conclude that Myo5b defects result in PKA stimulation that activates residual channels on the surface when intestinal epithelia are exposed to glucocorticoids at birth.
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Affiliation(s)
- Radia Forteza
- Department of Cell Biology, Miller School of Medicine, University of Miami, Miami, FL 33136
| | - M Kaimul Ahsan
- Department of Pediatrics, Yale School of Medicine, Yale University, New Haven, CT 06510
| | - Fernando Cartón-García
- Group of Biomedical Research in Digestive Tract Tumors, CIBBIM-Nanomedicine, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autónoma de Barcelona, 08035 Barcelona, Spain
| | - Diego Arango
- Group of Biomedical Research in Digestive Tract Tumors, CIBBIM-Nanomedicine, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autónoma de Barcelona, 08035 Barcelona, Spain
| | - Nadia A Ameen
- Department of Pediatrics, Yale School of Medicine, Yale University, New Haven, CT 06510
| | - Pedro J Salas
- Department of Cell Biology, Miller School of Medicine, University of Miami, Miami, FL 33136
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36
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Engevik AC, Kaji I, Postema MM, Faust JJ, Meyer AR, Williams JA, Fitz GN, Tyska MJ, Wilson JM, Goldenring JR. Loss of myosin Vb promotes apical bulk endocytosis in neonatal enterocytes. J Cell Biol 2019; 218:3647-3662. [PMID: 31562230 PMCID: PMC6829668 DOI: 10.1083/jcb.201902063] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/22/2019] [Accepted: 08/29/2019] [Indexed: 12/22/2022] Open
Abstract
In patients with inactivating mutations in myosin Vb (Myo5B), enterocytes show large inclusions lined by microvilli. The origin of inclusions in small-intestinal enterocytes in microvillus inclusion disease is currently unclear. We postulated that inclusions in Myo5b KO mouse enterocytes form through invagination of the apical brush border membrane. 70-kD FITC-dextran added apically to Myo5b KO intestinal explants accumulated in intracellular inclusions. Live imaging of Myo5b KO-derived enteroids confirmed the formation of inclusions from the apical membrane. Treatment of intestinal explants and enteroids with Dyngo resulted in accumulation of inclusions at the apical membrane. Inclusions in Myo5b KO enterocytes contained VAMP4 and Pacsin 2 (Syndapin 2). Myo5b;Pacsin 2 double-KO mice showed a significant decrease in inclusion formation. Our results suggest that apical bulk endocytosis in Myo5b KO enterocytes resembles activity-dependent bulk endocytosis, the primary mechanism for synaptic vesicle uptake during intense neuronal stimulation. Thus, apical bulk endocytosis mediates the formation of inclusions in neonatal Myo5b KO enterocytes.
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Affiliation(s)
- Amy C Engevik
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Izumi Kaji
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Meagan M Postema
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - James J Faust
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Anne R Meyer
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Janice A Williams
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN.,The Epithelial Biology Center and Vanderbilt University School of Medicine, Nashville, TN
| | - Gillian N Fitz
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN.,The Epithelial Biology Center and Vanderbilt University School of Medicine, Nashville, TN
| | - Jean M Wilson
- Department of Cellular and Molecular Medicine, Bio5 Institute, University of Arizona, Tucson, AZ
| | - James R Goldenring
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN .,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN.,The Epithelial Biology Center and Vanderbilt University School of Medicine, Nashville, TN.,The Nashville VA Medical Center, Nashville, TN
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Bidaud-Meynard A, Nicolle O, Heck M, Le Cunff Y, Michaux G. A V0-ATPase-dependent apical trafficking pathway maintains the polarity of the intestinal absorptive membrane. Development 2019; 146:dev174508. [PMID: 31110027 PMCID: PMC7376742 DOI: 10.1242/dev.174508] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/07/2019] [Indexed: 12/18/2022]
Abstract
Intestine function relies on the strong polarity of intestinal epithelial cells and the array of microvilli forming a brush border at their luminal pole. Combining a genetic RNA interference (RNAi) screen with in vivo super-resolution imaging in the Caenorhabditiselegans intestine, we found that the V0 sector of the vacuolar ATPase (V0-ATPase) controls a late apical trafficking step, involving Ras-related protein 11 (RAB-11)+ endosomes and the N-ethylmaleimide-sensitive factor-attachment protein receptor (SNARE) synaptosome-associated protein 29 (SNAP-29), and is necessary to maintain the polarized localization of both apical polarity modules and brush border proteins. We show that the V0-ATPase pathway also genetically interacts with glycosphingolipids and clathrin in enterocyte polarity maintenance. Finally, we demonstrate that silencing of the V0-ATPase fully recapitulates the severe structural, polarity and trafficking defects observed in enterocytes from individuals with microvillus inclusion disease (MVID) and use this new in vivo MVID model to follow the dynamics of microvillus inclusions. Thus, we describe a new function for V0-ATPase in apical trafficking and epithelial polarity maintenance and the promising use of the C. elegans intestine as an in vivo model to better understand the molecular mechanisms of rare genetic enteropathies.
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Affiliation(s)
- Aurélien Bidaud-Meynard
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Ophélie Nicolle
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Markus Heck
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Yann Le Cunff
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Grégoire Michaux
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000 Rennes, France
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Grassini DR, da Silva J, Hall TE, Baillie GJ, Simons C, Parton RG, Hogan BM, Smith KA. Myosin Vb is required for correct trafficking of N-cadherin and cardiac chamber ballooning. Dev Dyn 2019; 248:284-295. [PMID: 30801852 DOI: 10.1002/dvdy.19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 01/29/2019] [Accepted: 01/30/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND During heart morphogenesis, the cardiac chambers undergo ballooning: a process involving regionalized elongation of cardiomyocytes. Cardiomyocyte shape changes require reorganization of the actin cytoskeleton; however, the genetic regulation of this process is not well understood. RESULTS From a forward genetic screen, we identified the zebrafish uq 23ks mutant which manifests chamber ballooning defects. Whole-genome sequencing-mapping identified a truncating mutation in the gene, myo5b. myo5b encodes an atypical myosin required for endosome recycling and, consistent with this, increased vesicles were observed in myo5b mutant cardiomyocytes. Expression of RFP-Rab11a (a recycling endosome marker) confirmed increased recycling endosomes in cardiomyocytes of myo5b mutants. To investigate potential cargo of MyoVb-associated vesicles, we examined the adherens junction protein, N-cadherin. N-cadherin appeared mispatterned at cell junctions, and an increase in the number of intracellular particles was also apparent. Co-localization with RFP-Rab11a confirmed increased N-cadherin-positive recycling endosomes, demonstrating N-cadherin trafficking is perturbed in myo5b mutants. Finally, phalloidin staining showed disorganized F-actin in myo5b cardiomyocytes, suggesting the cytoskeleton fails to remodel, obstructing chamber ballooning. CONCLUSIONS MyoVb is required for cardiomyocyte endosomal recycling and appropriate N-cadherin localization during the onset of chamber ballooning. Cardiomyocytes lacking MyoVb are unable to reorganize their actin cytoskeleton, resulting in failed chamber ballooning. Developmental Dynamics 248:284-295, 2019. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Daniela R Grassini
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Jason da Silva
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Thomas E Hall
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Gregory J Baillie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Cas Simons
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Robert G Parton
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Benjamin M Hogan
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Kelly A Smith
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
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Reynier M, Allart S, Goudounèche D, Moga A, Serre G, Simon M, Leprince C. The Actin-Based Motor Myosin Vb Is Crucial to Maintain Epidermal Barrier Integrity. J Invest Dermatol 2019; 139:1430-1438. [PMID: 30660668 DOI: 10.1016/j.jid.2018.12.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 01/07/2023]
Abstract
Myosin Vb (Myo5b) is an unconventional myosin involved in the actin-dependent transport and tethering of intracellular organelles. In the epidermis, granular keratinocytes accumulate cytoplasmic lamellar bodies (LBs), secretory vesicles released at the junction with the stratum corneum that participate actively in the maintenance of the epidermal barrier. We have previously demonstrated that LB biogenesis is controlled by the Rab11a guanosine triphosphate hydrolase, known for its ability to recruit the Myo5b motor. In order to better characterize the molecular pathway that controls LB trafficking, we analyzed the role of F-actin and Myo5b in the epidermis. We demonstrated that LB distribution in granular keratinocytes was dependent on a dynamic F-actin cytoskeleton. Myo5b was shown to be highly expressed in granular keratinocytes and associated with corneodesmosin-loaded LB. In reconstructed human epidermis, Myo5b silencing led to epidermal barrier defects associated with structural alterations of the stratum corneum and a reduced pool of LB showing signs of disordered maturation. Myo5b depletion also disturbed the expression and distribution of both LB cargoes and junctional components, such as claudin-1, which demonstrates its action on both LB trafficking and junctional complex composition. Together, our data reveal the essential role of Myo5b in maintaining the epidermal barrier integrity.
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Affiliation(s)
- Marie Reynier
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, U1056, Institut National de la Santé et de la Recherche Médicale, University of Toulouse, Toulouse, France
| | - Sophie Allart
- Centre de Physiopathologie de Toulouse Purpan, U1043, Institut National de la Santé et de la Recherche Médicale, TRI Genotoul, Toulouse, France
| | - Dominique Goudounèche
- Centre de Microscopie Electronique Appliquée à la Biologie, Faculté de Médecine Rangueil, University of Toulouse, Toulouse, France
| | | | - Guy Serre
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, U1056, Institut National de la Santé et de la Recherche Médicale, University of Toulouse, Toulouse, France
| | - Michel Simon
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, U1056, Institut National de la Santé et de la Recherche Médicale, University of Toulouse, Toulouse, France
| | - Corinne Leprince
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde, U1056, Institut National de la Santé et de la Recherche Médicale, University of Toulouse, Toulouse, France.
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Julia J, Shui V, Mittal N, Heim-Hall J, Blanco CL. Microvillus inclusion disease, a diagnosis to consider when abnormal stools and neurological impairments run together due to a rare syntaxin 3 gene mutation. J Neonatal Perinatal Med 2019; 12:313-319. [PMID: 30909251 DOI: 10.3233/npm-1852] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
BACKGROUND Microvillus Inclusion Disease (MVID) was first described in the literature in 1978 with presentation of severe watery diarrhea, failure to thrive, and metabolic acidosis. Mutations in the myosin Vb (MYO5B) gene have been identified as causative for MVID, but other clinical manifestations and associations with novel mutations are lacking. METHODS We report a full-term infant admitted to the neonatal intensive care unit (NICU) with abdominal distension and inability to sustain full enteral feeds. A retrospective chart review and review of the literature was performed. RESULTS An infant with abnormal, mucoid-like stringy stools was incidentally found to have severe metabolic acidosis on routine lab monitoring. Acidosis corrected with total parenteral nutrition (TPN), but the infant experienced recurrent episodes of acidosis with enteral feeds. He was also noted to have abnormal ocular movements, fluctuating tonicity, and staring spells. He underwent an extensive workup and the diagnosis of microvillus inclusion disease was made by findings on electron microscopy. The diagnosis was confirmed with whole exome sequencing, showing a rare homozygous mutation in the syntaxin 3 (STX3) gene. This is the fifth reported patient with microvillus inclusion disease with a mutation in this gene, and the first with abnormal neurologic findings. CONCLUSION It is important to consider MVID in the differential diagnosis of a neonate or infant with abnormal stools, metabolic acidosis, with and without neurologic symptoms for prompt referral and treatment.
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Affiliation(s)
- Jacqueline Julia
- Department of Pediatrics, University of Texas Health Science Center at San Antonio and University Health System, San Antonio, TX, USA
| | - Valerie Shui
- Department of Pediatrics, University of Texas Health Science Center at San Antonio and University Health System, San Antonio, TX, USA
| | - Naveen Mittal
- Department of Pediatrics, University of Texas Health Science Center at San Antonio and University Health System, San Antonio, TX, USA
| | - Josefine Heim-Hall
- Department of Pathology, University of Texas Health Science Center at San Antonio and University Health System, San Antonio, TX, USA
| | - Cynthia L Blanco
- Department of Pediatrics, University of Texas Health Science Center at San Antonio and University Health System, San Antonio, TX, USA
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Engevik AC, Kaji I, Engevik MA, Meyer AR, Weis VG, Goldstein A, Hess MW, Müller T, Koepsell H, Dudeja PK, Tyska M, Huber LA, Shub MD, Ameen N, Goldenring JR. Loss of MYO5B Leads to Reductions in Na + Absorption With Maintenance of CFTR-Dependent Cl - Secretion in Enterocytes. Gastroenterology 2018; 155:1883-1897.e10. [PMID: 30144427 PMCID: PMC6279525 DOI: 10.1053/j.gastro.2018.08.025] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/19/2018] [Accepted: 08/06/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS Inactivating mutations in MYO5B cause microvillus inclusion disease (MVID), but the physiological cause of the diarrhea associated with this disease is unclear. We investigated whether loss of MYO5B results in aberrant expression of apical enterocyte transporters. METHODS We studied alterations in apical membrane transporters in MYO5B-knockout mice, as well as mice with tamoxifen-inducible, intestine-specific disruption of Myo5b (VilCreERT2;Myo5bflox/flox mice) or those not given tamoxifen (controls). Intestinal tissues were collected from mice and analyzed by immunostaining, immunoelectron microscopy, or cultured enteroids were derived. Functions of brush border transporters in intestinal mucosa were measured in Ussing chambers. We obtained duodenal biopsy specimens from individuals with MVID and individuals without MVID (controls) and compared transporter distribution by immunocytochemistry. RESULTS Compared to intestinal tissues from littermate controls, intestinal tissues from MYO5B-knockout mice had decreased apical localization of SLC9A3 (also called NHE3), SLC5A1 (also called SGLT1), aquaporin (AQP) 7, and sucrase isomaltase, and subapical localization of intestinal alkaline phosphatase and CDC42. However, CFTR was present on apical membranes of enterocytes from MYO5B knockout and control mice. Intestinal biopsies from patients with MVID had subapical localization of NHE3, SGLT1, and AQP7, but maintained apical CFTR. After tamoxifen administration, VilCreERT2;Myo5bflox/flox mice lost apical NHE3, SGLT1, DRA, and AQP7, similar to germline MYO5B knockout mice. Intestinal tissues from VilCreERT2;Myo5bflox/flox mice had increased CFTR in crypts and CFTR localized to the apical membranes of enterocytes. Intestinal mucosa from VilCreERT2;Myo5bflox/flox mice given tamoxifen did not have an intestinal barrier defect, based on Ussing chamber analysis, but did have decreased SGLT1 activity and increased CFTR activity. CONCLUSIONS Although trafficking of many apical transporters is regulated by MYO5B, trafficking of CFTR is largely independent of MYO5B. Decreased apical localization of NHE3, SGLT1, DRA, and AQP7 might be responsible for dysfunctional water absorption in enterocytes of patients with MVID. Maintenance of apical CFTR might exacerbate water loss by active secretion of chloride into the intestinal lumen.
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Affiliation(s)
- Amy C Engevik
- Departments of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Izumi Kaji
- Departments of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Melinda A Engevik
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas; Department of Pathology, Texas Children's Hospital, Houston, Texas
| | - Anne R Meyer
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Victoria G Weis
- Departments of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Anna Goldstein
- Departments of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Nashville Veterans Affairs Medical Center, Nashville, Tennessee
| | - Michael W Hess
- Division of Histology and Embryology, Innsbruck Medical University, Innsbruck, Austria
| | - Thomas Müller
- Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Hermann Koepsell
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, University of Würzburg, Würzburg, Germany
| | - Pradeep K Dudeja
- Department of Medicine, University of Illinois, Chicago and the Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Matthew Tyska
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Lukas A Huber
- Division of Cell Biology, Biocenter and Innsbruck Medical University, Innsbruck, Austria; Austrian Drug Screening Institute, Innsbruck, Austria
| | - Mitchell D Shub
- Division of Gastroenterology and Phoenix Children's Hospital and the Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona
| | - Nadia Ameen
- Department of Pediatrics, Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut
| | - James R Goldenring
- Departments of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee; Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee; Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee; Nashville Veterans Affairs Medical Center, Nashville, Tennessee.
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Schlegel C, Lapierre LA, Weis VG, Williams JA, Kaji I, Pinzon-Guzman C, Prasad N, Boone B, Jones A, Correa H, Levy SE, Han X, Wang M, Thomsen K, Acra S, Goldenring JR. Reversible deficits in apical transporter trafficking associated with deficiency in diacylglycerol acyltransferase. Traffic 2018; 19:879-892. [PMID: 30095213 PMCID: PMC6191315 DOI: 10.1111/tra.12608] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 11/30/2022]
Abstract
Deficiency in diacylglycerol acyltransferase (DGAT1) is a rare cause of neonatal diarrhea, without a known mechanism or in vitro model. A patient presenting at our institution at 7 weeks of life with failure to thrive and diarrhea was found by whole-exome sequencing to have a homozygous DGAT1 truncation mutation. Duodenal biopsies showed loss of DGAT1 and deficits in apical membrane transporters and junctional proteins in enterocytes. When placed on a very low-fat diet, the patient's diarrhea resolved with normalization of brush border transporter localization in endoscopic biopsies. DGAT1 knockdown in Caco2-BBe cells modeled the deficits in apical trafficking, with loss of apical DPPIV and junctional occludin. Elevation in cellular lipid levels, including diacylglycerol (DAG) and phospholipid metabolites of DAG, was documented by lipid analysis in DGAT1 knockdown cells. Culture of the DGAT1 knockdown cells in lipid-depleted media led to re-establishment of occludin and return of apical DPPIV. DGAT1 loss appears to elicit global changes in enterocyte polarized trafficking that could account for deficits in absorption seen in the patient. The in vitro modeling of this disease should allow for investigation of possible therapeutic targets.
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Affiliation(s)
- Cameron Schlegel
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
| | - Lynne A. Lapierre
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
- Department of Vanderbilt University School of Medicine and the Nashville VA Medical Center, Nashville, TN, USA
| | - Victoria G. Weis
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
| | - Janice A. Williams
- Department of Cell Imaging Share Resource and the Nashville VA Medical Center, Nashville, TN, USA
| | - Izumi Kaji
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
| | - Carolina Pinzon-Guzman
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
| | - Nripesh Prasad
- Department of Vanderbilt University School of Medicine and the Nashville VA Medical Center, Nashville, TN, USA
| | - Braden Boone
- HudsonAlpha Institute for Biotechnology, Huntsville, AL
| | - Angela Jones
- HudsonAlpha Institute for Biotechnology, Huntsville, AL
| | - Hernan Correa
- Department of Pathology, Microbiology and Immunology and the Nashville VA Medical Center, Nashville, TN, USA
| | - Shawn E. Levy
- HudsonAlpha Institute for Biotechnology, Huntsville, AL
| | - Xianlin Han
- Departments of Medicine & Biochemistry, Barshop Institute for Longevity and Aging Studies, University of Texas Health, San Antonio, TX, USA
| | - Miao Wang
- Departments of Medicine & Biochemistry, Barshop Institute for Longevity and Aging Studies, University of Texas Health, San Antonio, TX, USA
| | - Kelly Thomsen
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, and the Nashville VA Medical Center, Nashville, TN, USA
| | - Sari Acra
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, and the Nashville VA Medical Center, Nashville, TN, USA
| | - James R. Goldenring
- Department of Surgery and the Nashville VA Medical Center, Nashville, TN, USA
- Department of Cell & Developmental Biology and the Nashville VA Medical Center, Nashville, TN, USA
- Department of the Epithelial Biology Center and the Nashville VA Medical Center, Nashville, TN, USA
- Department of Vanderbilt University School of Medicine and the Nashville VA Medical Center, Nashville, TN, USA
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Dey I, Bradbury NA. Physiology of the Gut: Experimental Models for Investigating Intestinal Fluid and Electrolyte Transport. CURRENT TOPICS IN MEMBRANES 2018; 81:337-381. [PMID: 30243437 DOI: 10.1016/bs.ctm.2018.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Once thought to be exclusively an absorptive tissue, the intestine is now recognized as an important secretory tissue, playing a key role in body ion and fluid homeostasis. Given the intestine's role in fluid homeostasis, it is not surprising that important clinical pathologies arise from imbalances in fluid absorption and secretion. Perhaps the most important examples of this can be seen in enterotoxigenic secretory diarrheas with extreme fluid secretion, and Cystic Fibrosis with little or no fluid secretion. A mechanistic understanding of the cellular pathways regulating ion and fluid transport has been obtained from a variety of approaches and model systems. These have ranged from the intact intestine to a single intestinal epithelial cell type. Although for many years a reductionist approach has held sway for investigating intestinal transport, the growing realization that physiologic processes should really be examined within a physiological context has seen a marked increase in studies using models that are essentially mini-intestines in a dish. The aim of this chapter is to provide a historical context for our understanding of intestinal ion and fluid transport, and to highlight the model systems that have been used to acquire this knowledge.
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Affiliation(s)
- Isha Dey
- Department of Physiology and Biophysics, Chicago Medical School, North Chicago, IL, United States
| | - Neil A Bradbury
- Department of Physiology and Biophysics, Chicago Medical School, North Chicago, IL, United States
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Mosa MH, Nicolle O, Maschalidi S, Sepulveda FE, Bidaud-Meynard A, Menche C, Michels BE, Michaux G, de Saint Basile G, Farin HF. Dynamic Formation of Microvillus Inclusions During Enterocyte Differentiation in Munc18-2-Deficient Intestinal Organoids. Cell Mol Gastroenterol Hepatol 2018; 6:477-493.e1. [PMID: 30364784 PMCID: PMC6198061 DOI: 10.1016/j.jcmgh.2018.08.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 08/02/2018] [Indexed: 12/25/2022]
Abstract
BACKGROUND & AIMS Microvillus inclusion disease (MVID) is a congenital intestinal malabsorption disorder caused by defective apical vesicular transport. Existing cellular models do not fully recapitulate this heterogeneous pathology. The aim of this study was to characterize 3-dimensional intestinal organoids that continuously generate polarized absorptive cells as an accessible and relevant model to investigate MVID. METHODS Intestinal organoids from Munc18-2/Stxbp2-null mice that are deficient for apical vesicular transport were subjected to enterocyte-specific differentiation protocols. Lentiviral rescue experiments were performed using human MUNC18-2 variants. Apical trafficking and microvillus formation were characterized by confocal and transmission electron microscopy. Spinning disc time-lapse microscopy was used to document the lifecycle of microvillus inclusions. RESULTS Loss of Munc18-2/Stxbp2 recapitulated the pathologic features observed in patients with MUNC18-2 deficiency. The defects were fully restored by transgenic wild-type human MUNC18-2 protein, but not the patient variant (P477L). Importantly, we discovered that the MVID phenotype was correlated with the degree of enterocyte differentiation: secretory vesicles accumulated already in crypt progenitors, while differentiated enterocytes showed an apical tubulovesicular network and enlarged lysosomes. Upon prolonged enterocyte differentiation, cytoplasmic F-actin-positive foci were observed that further progressed into classic microvillus inclusions. Time-lapse microscopy showed their dynamic formation by intracellular maturation or invagination of the apical or basolateral plasma membrane. CONCLUSIONS We show that prolonged enterocyte-specific differentiation is required to recapitulate the entire spectrum of MVID. Primary organoids can provide a powerful model for this heterogeneous pathology. Formation of microvillus inclusions from multiple membrane sources showed an unexpected dynamic of the enterocyte brush border.
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Key Words
- 3D, 3-dimensional
- Apical Vesicular Transport
- Brush Border Formation
- DAPI, 4′,6-diamidino-2-phenylindole
- Disease Modeling
- EGFP, enhanced green fluorescent protein
- FHL5, familial hemophagocytic lymphohistiocytosis type 5
- IWP-2, inhibitor of WNT production-2
- KO, knock-out
- MVID, microvillus inclusion disease
- MVIs, microvillus inclusions
- Microvillus Atrophy
- PBS, phosphate-buffered saline
- STXBP2, syntaxin binding protein 2
- Stx3, syntaxin 3
- TEM, transmission electron microscopy
- VPA, valproic acid
- WT, wild-type
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Affiliation(s)
- Mohammed H. Mosa
- German Cancer Consortium (Deutsches Konsortium für Translationale Krebsforschung), Heidelberg, Germany,Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany,German Cancer Research Center (Deutsches Krebsforschungszentrum), Heidelberg, Germany
| | - Ophélie Nicolle
- University Rennes, Centre national de la recherche scientifique, Institut de Génétique et Développement de Rennes UMR6290, Rennes, France
| | - Sophia Maschalidi
- INSERM UMR1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France,Imagine Institute, Paris Descartes University–Sorbonne Paris Cité, Paris, France
| | - Fernando E. Sepulveda
- INSERM UMR1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France,Imagine Institute, Paris Descartes University–Sorbonne Paris Cité, Paris, France
| | - Aurelien Bidaud-Meynard
- University Rennes, Centre national de la recherche scientifique, Institut de Génétique et Développement de Rennes UMR6290, Rennes, France
| | - Constantin Menche
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany
| | - Birgitta E. Michels
- German Cancer Consortium (Deutsches Konsortium für Translationale Krebsforschung), Heidelberg, Germany,Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany,German Cancer Research Center (Deutsches Krebsforschungszentrum), Heidelberg, Germany,Faculty of Biological Sciences, Goethe University Frankfurt, Germany
| | - Grégoire Michaux
- University Rennes, Centre national de la recherche scientifique, Institut de Génétique et Développement de Rennes UMR6290, Rennes, France,Correspondence Address correspondence to: Grégoire Michaux, PhD, University Rennes, Institut de Génétique et Développement de Rennes, Rennes, France.
| | - Geneviève de Saint Basile
- INSERM UMR1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France,Imagine Institute, Paris Descartes University–Sorbonne Paris Cité, Paris, France,Centre d’Etudes des Déficites Immunitaires, Assistance Publique-Hôpitaux de Paris, France,Geneviève de Saint Basile, MD, PhD, INSERM, Paris, France.
| | - Henner F. Farin
- German Cancer Consortium (Deutsches Konsortium für Translationale Krebsforschung), Heidelberg, Germany,Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany,German Cancer Research Center (Deutsches Krebsforschungszentrum), Heidelberg, Germany,Henner F. Farin, PhD, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main, Germany.
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45
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2018. [PMID: 28632484 DOI: 10.1080/215412481336191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
- b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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Abstract
The delivery of intracellular material within cells is crucial for maintaining normal function. Myosins transport a wide variety of cargo, ranging from vesicles to ribonuclear protein particles (RNPs), in plants, fungi, and metazoa. The properties of a given myosin transporter are adapted to move on different actin filament tracks, either on the disordered actin networks at the cell cortex or along highly organized actin bundles to distribute their cargo in a localized manner or move it across long distances in the cell. Transport is controlled by selective recruitment of the myosin to its cargo that also plays a role in activation of the motor.
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Affiliation(s)
- Margaret A Titus
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota 55455
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Schneeberger K, Roth S, Nieuwenhuis EES, Middendorp S. Intestinal epithelial cell polarity defects in disease: lessons from microvillus inclusion disease. Dis Model Mech 2018; 11:11/2/dmm031088. [PMID: 29590640 PMCID: PMC5894939 DOI: 10.1242/dmm.031088] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The intestinal epithelium is a highly organized tissue. The establishment of epithelial cell polarity, with distinct apical and basolateral plasma membrane domains, is pivotal for both barrier formation and for the uptake and vectorial transport of nutrients. The establishment of cell polarity requires a specialized subcellular machinery to transport and recycle proteins to their appropriate location. In order to understand and treat polarity-associated diseases, it is necessary to understand epithelial cell-specific trafficking mechanisms. In this Review, we focus on cell polarity in the adult mammalian intestine. We discuss how intestinal epithelial polarity is established and maintained, and how disturbances in the trafficking machinery can lead to a polarity-associated disorder, microvillus inclusion disease (MVID). Furthermore, we discuss the recent developments in studying MVID, including the creation of genetically manipulated cell lines, mouse models and intestinal organoids, and their uses in basic and applied research. Summary: Microvillus inclusion disease serves as a useful model to enhance our understanding of the intestinal trafficking and polarity machinery in health and disease.
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Affiliation(s)
- Kerstin Schneeberger
- Division of Paediatrics, Department of Paediatric Gastroenterology, Wilhelmina Children's Hospital, 3584 CT, Utrecht, The Netherlands
| | - Sabrina Roth
- Division of Paediatrics, Department of Paediatric Gastroenterology, Wilhelmina Children's Hospital, 3584 CT, Utrecht, The Netherlands
| | - Edward E S Nieuwenhuis
- Division of Paediatrics, Department of Paediatric Gastroenterology, Wilhelmina Children's Hospital, 3584 CT, Utrecht, The Netherlands
| | - Sabine Middendorp
- Division of Paediatrics, Department of Paediatric Gastroenterology, Wilhelmina Children's Hospital, 3584 CT, Utrecht, The Netherlands .,Regenerative Medicine Center Utrecht, University Medical Centre (UMC) Utrecht, 3584 CT, Utrecht, The Netherlands
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48
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Dhekne HS, Pylypenko O, Overeem AW, Zibouche M, Ferreira RJ, van der Velde KJ, Rings EHHM, Posovszky C, van der Sluijs P, Swertz MA, Houdusse A, van IJzendoorn SCD. MYO5B, STX3, and STXBP2 mutations reveal a common disease mechanism that unifies a subset of congenital diarrheal disorders: A mutation update. Hum Mutat 2018; 39:333-344. [PMID: 29266534 PMCID: PMC5838515 DOI: 10.1002/humu.23386] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/30/2017] [Accepted: 12/12/2017] [Indexed: 12/15/2022]
Abstract
Microvillus inclusion disease (MVID) is a rare but fatal autosomal recessive congenital diarrheal disorder caused by MYO5B mutations. In 2013, we launched an open‐access registry for MVID patients and their MYO5B mutations (www.mvid-central.org). Since then, additional unique MYO5B mutations have been identified in MVID patients, but also in non‐MVID patients. Animal models have been generated that formally prove the causality between MYO5B and MVID. Importantly, mutations in two other genes, STXBP2 and STX3, have since been associated with variants of MVID, shedding new light on the pathogenesis of this congenital diarrheal disorder. Here, we review these additional genes and their mutations. Furthermore, we discuss recent data from cell studies that indicate that the three genes are functionally linked and, therefore, may constitute a common disease mechanism that unifies a subset of phenotypically linked congenital diarrheal disorders. We present new data based on patient material to support this. To congregate existing and future information on MVID geno‐/phenotypes, we have updated and expanded the MVID registry to include all currently known MVID‐associated gene mutations, their demonstrated or predicted functional consequences, and associated clinical information.
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Affiliation(s)
- Herschel S Dhekne
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Olena Pylypenko
- Structural Motility, Institute Curie, Centre de Reserche, Paris, France
| | - Arend W Overeem
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Malik Zibouche
- Department of Cell Biology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Rosaria J Ferreira
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - K Joeri van der Velde
- Genomics Coordination Center, Department of Genetics, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Edmond H H M Rings
- Department of Pediatrics, Erasmus Medical Center Rotterdam, Erasmus University Rotterdam, Rotterdam, The Netherlands.,Department of Pediatrics, Leiden University Medical Center, Leiden University, Leiden, The Netherlands
| | - Carsten Posovszky
- Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
| | - Peter van der Sluijs
- Department of Cell Biology, University Medical Center Utrecht, Utrecht, the Netherlands,Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | - Morris A Swertz
- Genomics Coordination Center, Department of Genetics, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Anne Houdusse
- Structural Motility, Institute Curie, Centre de Reserche, Paris, France
| | - Sven C D van IJzendoorn
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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49
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Engevik AC, Goldenring JR. Trafficking Ion Transporters to the Apical Membrane of Polarized Intestinal Enterocytes. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a027979. [PMID: 28264818 DOI: 10.1101/cshperspect.a027979] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Epithelial cells lining the gastrointestinal tract require distinct apical and basolateral domains to function properly. Trafficking and insertion of enzymes and transporters into the apical brush border of intestinal epithelial cells is essential for effective digestion and absorption of nutrients. Specific critical ion transporters are delivered to the apical brush border to facilitate fluid and electrolyte uptake. Maintenance of these apical transporters requires both targeted delivery and regulated membrane recycling. Examination of altered apical trafficking in patients with Microvillus Inclusion disease caused by inactivating mutations in MYO5B has led to insights into the regulation of apical trafficking by elements of the apical recycling system. Modeling of MYO5B loss in cell culture and animal models has led to recognition of Rab11a and Rab8a as critical regulators of apical brush border function. All of these studies show the importance of apical membrane trafficking dynamics in maintenance of polarized epithelial cell function.
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Affiliation(s)
- Amy Christine Engevik
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee 37232.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - James R Goldenring
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, Tennessee 37232.,Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee 37232.,Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee 37232.,Nashville VA Medical Center, Nashville, Tennessee 37232
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50
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Cox CM, Lu R, Salcin K, Wilson JM. The Endosomal Protein Endotubin Is Required for Enterocyte Differentiation. Cell Mol Gastroenterol Hepatol 2017; 5:145-156. [PMID: 29322087 PMCID: PMC5756061 DOI: 10.1016/j.jcmgh.2017.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/07/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS During late embryonic development and through weaning, enterocytes of the ileum are highly endocytic. Defects in endocytosis and trafficking are implicated in neonatal disease, however, the mechanisms regulating trafficking during the developmental period are incompletely understood. The apical endosomal protein endotubin (EDTB) is highly expressed in the late embryonic and neonatal ileum. In epithelial cells in vitro, EDTB regulates both trafficking of tight junction proteins and proliferation through modulation of YAP activity. However, EDTB function during the endocytic stage of development of the intestine is unknown. METHODS By using Villin-CreERT2, we induced knockout of EDTB during late gestation and analyzed the impact on endocytic compartments and enterocyte structure in neonates using immunofluorescence, immunocytochemistry, and transmission electron microscopy. RESULTS Deletion of the apical endosomal protein EDTB in the small intestine during development impairs enterocyte morphogenesis, including loss of the apical endocytic complex, defective formation of the lysosomal compartment, and some cells had large microvillus-rich inclusions similar to those observed in microvillus inclusion disease. There also was a decrease in apical endocytosis and mislocalization of proteins involved in apical trafficking. CONCLUSIONS Our results show that EDTB-mediated trafficking within the epithelial cells of the developing ileum is important for maintenance of endocytic compartments and enterocyte integrity during early stages of gut development.
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Key Words
- AEC, apical endocytic complex
- AP, alkaline phosphatase
- CRISPR/Cas9, clustered regularly interspaced short palindromic repeats/cas9 endonuclease
- EDTB, endotubin
- EEA1, early endosomal antigen 1
- Endosomes
- Endotubin
- G, guide
- GFP, green fluorescent protein
- GTPase, guanosine triphosphatase
- KO, knockout
- LAMP1, lysosome-associated membrane protein 1
- MAMDC4, MAM domain containing 4
- MVID, microvillus inclusion disease
- P, postnatal day
- PBS, phosphate-buffered saline
- PCR, polymerase chain reaction
- Rab
- SDS, sodium dodecyl sulfate
- TBST, tris-buffered saline with 0.1% tween-20
- TEM, transmission electron microscopic
- TJ, tight junction
- Tight Junction
- Trafficking
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Affiliation(s)
- Christopher M. Cox
- Department of Cell and Molecular Medicine, University of Arizona, Tucson, Arizona
| | - Ruifeng Lu
- Department of Cell and Molecular Medicine, University of Arizona, Tucson, Arizona,Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida
| | - Kaan Salcin
- Department of Cell and Molecular Medicine, University of Arizona, Tucson, Arizona,McGill University, Montreal, Canada
| | - Jean M. Wilson
- Department of Cell and Molecular Medicine, University of Arizona, Tucson, Arizona,Correspondence Address correspondence to: Jean M. Wilson, PhD, Cell Biology and Anatomy, University of Arizona, PO Box 245044, Tucson, Arizona 85724. fax: (520) 626-2097.
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