1
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Wang JY, Michki NS, Sitaraman S, Banaschewski BJ, Lin SM, Katzen JB, Basil MC, Cantu E, Zepp JA, Frank DB, Young LR. Dysregulated alveolar epithelial cell progenitor function and identity in Hermansky-Pudlak syndrome pulmonary fibrosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.17.545390. [PMID: 38496421 PMCID: PMC10942273 DOI: 10.1101/2023.06.17.545390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Hermansky-Pudlak syndrome (HPS) is a genetic disorder of endosomal protein trafficking associated with pulmonary fibrosis in specific subtypes, including HPS-1 and HPS-2. Single mutant HPS1 and HPS2 mice display increased fibrotic sensitivity while double mutant HPS1/2 mice exhibit spontaneous fibrosis with aging, which has been attributed to HPS mutations in alveolar epithelial type II (AT2) cells. We utilized HPS mouse models and human lung tissue to investigate mechanisms of AT2 cell dysfunction driving fibrotic remodeling in HPS. Starting at 8 weeks of age, HPS mice exhibited progressive loss of AT2 cell numbers. HPS AT2 cell was impaired ex vivo and in vivo. Incorporating AT2 cell lineage tracing in HPS mice, we observed aberrant differentiation with increased AT2-derived alveolar epithelial type I cells. Transcriptomic analysis of HPS AT2 cells revealed elevated expression of genes associated with aberrant differentiation and p53 activation. Lineage tracing and modeling studies demonstrated that HPS AT2 cells were primed to persist in a Krt8+ reprogrammed transitional state, mediated by p53 activity. Intrinsic AT2 progenitor cell dysfunction and p53 pathway dysregulation are novel mechanisms of disease in HPS-related pulmonary fibrosis, with the potential for early targeted intervention before the onset of fibrotic lung disease.
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2
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Li H, Aboudhiaf S, Parrot S, Scote-Blachon C, Benetollo C, Lin JS, Seugnet L. Pallidin function in Drosophila surface glia regulates sleep and is dependent on amino acid availability. Cell Rep 2023; 42:113025. [PMID: 37682712 DOI: 10.1016/j.celrep.2023.113025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 06/16/2023] [Accepted: 08/09/2023] [Indexed: 09/10/2023] Open
Abstract
The Pallidin protein is a central subunit of a multimeric complex called biogenesis of lysosome-related organelles complex 1 (BLOC1) that regulates specific endosomal functions and has been linked to schizophrenia. We show here that downregulation of Pallidin and other members of BLOC1 in the surface glia, the Drosophila equivalent of the blood-brain barrier, reduces and delays nighttime sleep in a circadian-clock-dependent manner. In agreement with BLOC1 involvement in amino acid transport, downregulation of the large neutral amino acid transporter 1 (LAT1)-like transporters JhI-21 and mnd, as well as of TOR (target of rapamycin) amino acid signaling, phenocopy Pallidin knockdown. Furthermore, supplementing food with leucine normalizes the sleep/wake phenotypes of Pallidin downregulation, and we identify a role for Pallidin in the subcellular trafficking of JhI-21. Finally, we provide evidence that Pallidin in surface glia is required for GABAergic neuronal activity. These data identify a BLOC1 function linking essential amino acid availability and GABAergic sleep/wake regulation.
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Affiliation(s)
- Hui Li
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Sami Aboudhiaf
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Sandrine Parrot
- Centre de Recherche en Neurosciences de Lyon, NeuroDialyTics Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Céline Scote-Blachon
- Centre de Recherche en Neurosciences de Lyon, GenCyTi Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Claire Benetollo
- Centre de Recherche en Neurosciences de Lyon, GenCyTi Facility, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Jian-Sheng Lin
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France
| | - Laurent Seugnet
- Centre de Recherche en Neurosciences de Lyon, Team WAKING, Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR 5292, 69675 Bron, France.
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3
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Wang JY, Young LR. Insights into the Pathogenesis of Pulmonary Fibrosis from Genetic Diseases. Am J Respir Cell Mol Biol 2022; 67:20-35. [PMID: 35294321 PMCID: PMC9273221 DOI: 10.1165/rcmb.2021-0557tr] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/16/2022] [Indexed: 11/24/2022] Open
Abstract
Pulmonary fibrosis is a disease process associated with significant morbidity and mortality, with limited therapeutic options owing to an incomplete understanding of the underlying pathophysiology. Mechanisms driving the fibrotic cascade have been elucidated through studies of rare and common variants in surfactant-related and telomere-related genes in familial and sporadic forms of pulmonary fibrosis, as well as in multisystem Mendelian genetic disorders that present with pulmonary fibrosis. In this translational review, we outline insights into the pathophysiology of pulmonary fibrosis derived from genetic forms of the disease, with a focus on model systems, shared cellular and molecular mechanisms, and potential targets for therapy.
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Affiliation(s)
- Joanna Y. Wang
- Division of Pulmonary, Allergy, and Critical Care, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Lisa R. Young
- Division of Pulmonary, Allergy, and Critical Care, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; and
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
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4
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Lee SY, Lee CM, Ma B, Kamle S, Elias JA, Zhou Y, Lee CG. Targeting Chitinase 1 and Chitinase 3-Like 1 as Novel Therapeutic Strategy of Pulmonary Fibrosis. Front Pharmacol 2022; 13:826471. [PMID: 35370755 PMCID: PMC8969576 DOI: 10.3389/fphar.2022.826471] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/18/2022] [Indexed: 11/21/2022] Open
Abstract
Chitinase 1 (CHIT1) and chitinase 3-like-1 (CHI3L1), two representative members of 18-Glycosyl hydrolases family, are significantly implicated in the pathogenesis of various human diseases characterized by inflammation and remodeling. Notably, dysregulated expression of CHIT1 and CHI3L1 was noted in the patients with pulmonary fibrosis and their levels were inversely correlated with clinical outcome of the patients. CHIT1 and CHI3L1, mainly expressed in alveolar macrophages, regulate profibrotic macrophage activation, fibroblast proliferation and myofibroblast transformation, and TGF-β signaling and effector function. Although the mechanism or the pathways that CHIT1 and CHI3L1 use to regulate pulmonary fibrosis have not been fully understood yet, these studies identify CHIT1 and CHI3L1 as significant modulators of fibroproliferative responses leading to persistent and progressive pulmonary fibrosis. These studies suggest a possibility that CHIT1 and CHI3L1 could be reasonable therapeutic targets to intervene or reverse established pulmonary fibrosis. In this review, we will discuss specific roles and regulatory mechanisms of CHIT1 and CHI3L1 in profibrotic cell and tissue responses as novel therapeutic targets of pulmonary fibrosis.
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Affiliation(s)
- Suh-Young Lee
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
- Devision of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University Hospital, Seoul, South Korea
| | - Chang-Min Lee
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
| | - Bing Ma
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
| | - Suchitra Kamle
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
| | - Jack A. Elias
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
| | - Yang Zhou
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
| | - Chun Geun Lee
- Molecular Microbiology and Immunology, Brown University, 185 Meeting St., Providence, RI, United States
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5
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Van de Vyver T, De Smedt SC, Raemdonck K. Modulating intracellular pathways to improve non-viral delivery of RNA therapeutics. Adv Drug Deliv Rev 2022; 181:114041. [PMID: 34763002 DOI: 10.1016/j.addr.2021.114041] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/12/2021] [Accepted: 11/02/2021] [Indexed: 12/12/2022]
Abstract
RNA therapeutics (e.g. siRNA, oligonucleotides, mRNA, etc.) show great potential for the treatment of a myriad of diseases. However, to reach their site of action in the cytosol or nucleus of target cells, multiple intra- and extracellular barriers have to be surmounted. Several non-viral delivery systems, such as nanoparticles and conjugates, have been successfully developed to meet this requirement. Unfortunately, despite these clear advances, state-of-the-art delivery agents still suffer from relatively low intracellular delivery efficiencies. Notably, our current understanding of the intracellular delivery process is largely oversimplified. Gaining mechanistic insight into how RNA formulations are processed by cells will fuel rational design of the next generation of delivery carriers. In addition, identifying which intracellular pathways contribute to productive RNA delivery could provide opportunities to boost the delivery performance of existing nanoformulations. In this review, we discuss both established as well as emerging techniques that can be used to assess the impact of different intracellular barriers on RNA transfection performance. Next, we highlight how several modulators, including small molecules but also genetic perturbation technologies, can boost RNA delivery by intervening at differing stages of the intracellular delivery process, such as cellular uptake, intracellular trafficking, endosomal escape, autophagy and exocytosis.
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Affiliation(s)
- Thijs Van de Vyver
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
| | - Stefaan C De Smedt
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
| | - Koen Raemdonck
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
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6
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Yuan Y, Liu T, Huang X, Chen Y, Zhang W, Li T, Yang L, Chen Q, Wang Y, Wei A, Li W. A zinc transporter, transmembrane protein 163, is critical for the biogenesis of platelet dense granules. Blood 2021; 137:1804-1817. [PMID: 33513603 PMCID: PMC8020268 DOI: 10.1182/blood.2020007389] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 01/03/2021] [Indexed: 11/20/2022] Open
Abstract
Lysosome-related organelles (LROs) are a category of secretory organelles enriched with ions such as calcium, which are maintained by ion transporters or channels. Homeostasis of these ions is important for LRO biogenesis and secretion. Hermansky-Pudlak syndrome (HPS) is a recessive disorder with defects in multiple LROs, typically platelet dense granules (DGs) and melanosomes. However, the underlying mechanism of DG deficiency is largely unknown. Using quantitative proteomics, we identified a previously unreported platelet zinc transporter, transmembrane protein 163 (TMEM163), which was significantly reduced in BLOC-1 (Dtnbp1sdy and Pldnpa)-, BLOC-2 (Hps6ru)-, or AP-3 (Ap3b1pe)-deficient mice and HPS patients (HPS2, HPS3, HPS5, HPS6, or HPS9). We observed similar platelet DG defects and higher intracellular zinc accumulation in platelets of mice deficient in either TMEM163 or dysbindin (a BLOC-1 subunit). In addition, we discovered that BLOC-1 was required for the trafficking of TMEM163 to perinuclear DG and late endosome marker-positive compartments (likely DG precursors) in MEG-01 cells. Our results suggest that TMEM163 is critical for DG biogenesis and that BLOC-1 is required for the trafficking of TMEM163 to putative DG precursors. These new findings suggest that loss of TMEM163 function results in disruption of intracellular zinc homeostasis and provide insights into the pathogenesis of HPS or platelet storage pool deficiency.
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Affiliation(s)
- Yefeng Yuan
- Beijing Key Laboratory for Genetics of Birth Defects/Beijing Pediatric Research Institute, MOE Key Laboratory of Major Diseases in Children, Genetics and Birth Defects Control Center/National Center for Children's Health, and Beijing Children's Hospital/Capital Medical University, Beijing, China
- University of Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Teng Liu
- Department of Dermatology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Shunyi Women and Children's Hospital of Beijing Children's Hospital, Beijing, China
| | - Xiahe Huang
- University of Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Yuanying Chen
- Beijing Key Laboratory for Genetics of Birth Defects/Beijing Pediatric Research Institute, MOE Key Laboratory of Major Diseases in Children, Genetics and Birth Defects Control Center/National Center for Children's Health, and Beijing Children's Hospital/Capital Medical University, Beijing, China
| | - Weilin Zhang
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; and
| | - Ting Li
- University of Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Lin Yang
- University of Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Quan Chen
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; and
- Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, Tianjin, China
| | - Yingchun Wang
- University of Chinese Academy of Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Aihua Wei
- Department of Dermatology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Wei Li
- Beijing Key Laboratory for Genetics of Birth Defects/Beijing Pediatric Research Institute, MOE Key Laboratory of Major Diseases in Children, Genetics and Birth Defects Control Center/National Center for Children's Health, and Beijing Children's Hospital/Capital Medical University, Beijing, China
- Shunyi Women and Children's Hospital of Beijing Children's Hospital, Beijing, China
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7
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Velázquez-Díaz P, Nakajima E, Sorkhdini P, Hernandez-Gutierrez A, Eberle A, Yang D, Zhou Y. Hermansky-Pudlak Syndrome and Lung Disease: Pathogenesis and Therapeutics. Front Pharmacol 2021; 12:644671. [PMID: 33841163 PMCID: PMC8028140 DOI: 10.3389/fphar.2021.644671] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/11/2021] [Indexed: 12/19/2022] Open
Abstract
Hermansky-Pudlak Syndrome (HPS) is a rare, genetic, multisystem disorder characterized by oculocutaneous albinism (OCA), bleeding diathesis, immunodeficiency, granulomatous colitis, and pulmonary fibrosis. HPS pulmonary fibrosis (HPS-PF) occurs in 100% of patients with subtype HPS-1 and has a similar presentation to idiopathic pulmonary fibrosis. Upon onset, individuals with HPS-PF have approximately 3 years before experiencing signs of respiratory failure and eventual death. This review aims to summarize current research on HPS along with its associated pulmonary fibrosis and its implications for the development of novel treatments. We will discuss the genetic basis of the disease, its epidemiology, and current therapeutic and clinical management strategies. We continue to review the cellular processes leading to the development of HPS-PF in alveolar epithelial cells, lymphocytes, mast cells, and fibrocytes, along with the molecular mechanisms that contribute to its pathogenesis and may be targeted in the treatment of HPS-PF. Finally, we will discuss emerging new cellular and molecular approaches for studying HPS, including lentiviral-mediated gene transfer, induced pluripotent stem cells (iPSCs), organoid and 3D-modelling, and CRISPR/Cas9-based gene editing approaches.
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Affiliation(s)
| | - Erika Nakajima
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States
| | - Parand Sorkhdini
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States
| | | | - Adam Eberle
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States
| | - Dongqin Yang
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States
| | - Yang Zhou
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States
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8
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Homma S, Ebina M, Kuwano K, Goto H, Sakai F, Sakamoto S, Johkoh T, Sugino K, Tachibana T, Terasaki Y, Nishioka Y, Hagiwara K, Hashimoto N, Hasegawa Y, Hebisawa A. Intractable diffuse pulmonary diseases: Manual for diagnosis and treatment. Respir Investig 2021; 59:8-33. [PMID: 32622842 DOI: 10.1016/j.resinv.2020.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/17/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
This manual has been compiled by a joint production committee with the Diffuse Lung Disease Assembly of the Japanese Respiratory Society (JRS) to provide a practical manual for the epidemiology, diagnosis, and treatment of intractable diffuse pulmonary diseases. The contents are based upon the results of research into these diseases by the Diffuse Pulmonary Diseases Study Group (principal researcher: Sakae Homma) supported by the FY2014-FY2016 Health and Labor Sciences Research Grant on Intractable Diseases. This manual focuses on: 1) pulmonary alveolar microlithiasis, 2) bronchiolitis obliterans, and 3) Hermansky-Pudlak Syndrome with interstitial pneumonia. As these are rare/intractable diffuse lung diseases (2 and 3 were first recognized as specified intractable diseases in 2015), there have not been sufficient epidemiological studies made, and there has been little progress in formulating diagnostic criteria and severity scales; however, the results of Japan's first surveys and research into such details are presented herein. In addition, the manual provides treatment guidance and actual cases for each disease, aiming to assist in the establishment of future modalities. The manual was produced with the goal of enabling clinicians specialized in respiratory apparatus to handle these diseases in clinical settings and of further advancing future research and treatment.
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Affiliation(s)
- Sakae Homma
- Department of Advanced and Integrated Interstitial Lung Diseases Research, School of Medicine, Toho University, Tokyo, Japan.
| | - Masahito Ebina
- Department of Respiratory Medicine in the 1st Internal Medicine, Tohoku Medical and Pharmaceutical University School of Medicine, Sendai, Japan.
| | - Kazuyoshi Kuwano
- Division of Respiratory Diseases, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.
| | - Hisatsugu Goto
- Department of Respiratory Medicine and Rheumatology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan.
| | - Fumikazu Sakai
- Department of Diagnostic Radiology, Saitama International Medical Center, Saitama Medical University, Saitama, Japan.
| | - Susumu Sakamoto
- Department of Respiratory Medicine, Toho University Omori Medical Center, Tokyo, Japan.
| | - Takeshi Johkoh
- Department of Radiology, Kinki Central Hospital of Mutual Aid Association of Public School Teachers, Hyogo, Japan.
| | - Keishi Sugino
- Department of Respiratory Medicine, Toho University Omori Medical Center, Tokyo, Japan.
| | - Teruo Tachibana
- Department of Internal Medicine, Aizenbashi Hospital, Osaka, Japan.
| | - Yasahiro Terasaki
- Department of Pathology (Analytic Human Pathology), Nippon Medical School, Tokyo, Japan.
| | - Yasuhiko Nishioka
- Department of Respiratory Medicine and Rheumatology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan.
| | - Koichi Hagiwara
- Division of Pulmonary Medicine, Jichi Medical University, Saitama, Japan.
| | - Naozumi Hashimoto
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Aichi, Japan.
| | - Yoshinori Hasegawa
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Aichi, Japan.
| | - Akira Hebisawa
- National Hospital Organization Tokyo Medical Center, Tokyo, Japan.
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9
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Chen OCW, Colaco A, Davis LC, Kiskin FN, Farhat NY, Speak AO, Smith DA, Morris L, Eden E, Tynan P, Churchill GC, Galione A, Porter FD, Platt FM. Defective platelet function in Niemann-Pick disease type C1. JIMD Rep 2020; 56:46-57. [PMID: 33204596 PMCID: PMC7653256 DOI: 10.1002/jmd2.12148] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/24/2020] [Accepted: 06/26/2020] [Indexed: 11/30/2022] Open
Abstract
Niemann-Pick disease type C (NPC) is a neurodegenerative lysosomal storage disorder caused by mutations in either NPC1 (95% of cases) or NPC2. Reduced late endosome/lysosome calcium (Ca2+) levels and the accumulation of unesterified cholesterol and sphingolipids within the late endocytic system characterize this disease. We previously reported impaired lysosome-related organelle (LRO) function in Npc1 -/- Natural Killer cells; however, the potential contribution of impaired acid compartment Ca2+ flux and LRO function in other cell types has not been determined. Here, we investigated LRO function in NPC1 disease platelets. We found elevated numbers of circulating platelets, impaired platelet aggregation and prolonged bleeding times in a murine model of NPC1 disease. Electron microscopy revealed abnormal ultrastructure in murine platelets, consistent with that seen in a U18666A (pharmacological inhibitor of NPC1) treated megakaryocyte cell line (MEG-01) exhibiting lipid storage and acidic compartment Ca2+ flux defects. Furthermore, platelets from NPC1 patients across different ages were found to cluster at the lower end of the normal range when platelet numbers were measured and had platelet volumes that were clustered at the top of the normal range. Taken together, these findings highlight the role of acid compartment Ca2+ flux in the function of platelet LROs.
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Affiliation(s)
| | | | | | | | - Nicole Y. Farhat
- Division in Translational MedicineEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human ServicesBethesdaMarylandUSA
| | | | | | - Lauren Morris
- Department of PharmacologyUniversity of OxfordOxfordUK
| | - Emily Eden
- Institute of Ophthalmology—Cell BiologyUniversity College LondonLondonUK
| | | | | | | | - Forbes D. Porter
- Division in Translational MedicineEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human ServicesBethesdaMarylandUSA
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10
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Combined deficiency of RAB32 and RAB38 in the mouse mimics Hermansky-Pudlak syndrome and critically impairs thrombosis. Blood Adv 2020; 3:2368-2380. [PMID: 31399401 DOI: 10.1182/bloodadvances.2019031286] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 07/01/2019] [Indexed: 12/11/2022] Open
Abstract
The biogenesis of lysosome related organelles is defective in Hermansky-Pudlak syndrome (HPS), a disorder characterized by oculocutaneous albinism and platelet dense granule (DG) defects. The first animal model of HPS was the fawn-hooded rat, harboring a spontaneous mutation inactivating the small guanosine triphosphatase Rab38 This leads to coat color dilution associated with the absence of DGs and lung morphological defects. Another RAB38 mutant, the cht mouse, has normal DGs, which has raised controversy about the role of RAB38 in DG biogenesis. We show here that murine and human, but not rat, platelets also express the closely related RAB32. To elucidate the parts played by RAB32 and RAB38 in the biogenesis of DGs in vivo and their effects on platelet functions, we generated mice inactivated for Rab32, Rab38, and both genes. Single Rab38 inactivation mimicked cht mice, whereas single Rab32 inactivation had no effect in DGs, coat color, or lung morphology. By contrast, Rab32/38 double inactivation mimicked severe HPS, with strong coat and eye pigment dilution, some enlarged lung multilamellar bodies associated with a decrease in the number of DGs. These organelles were morphologically abnormal, decreased in number, and devoid of 5-hydroxytryptamine content. In line with the storage pool defect, platelet activation was affected, resulting in severely impaired thrombus growth and prolongation of the bleeding time. Overall, our study demonstrates the absence of impact of RAB38 or RAB32 single deficiency in platelet biogenesis and function resulting from full redundancy, and characterized a new mouse model mimicking HPS devoid of DG content.
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11
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Bowman SL, Bi-Karchin J, Le L, Marks MS. The road to lysosome-related organelles: Insights from Hermansky-Pudlak syndrome and other rare diseases. Traffic 2020; 20:404-435. [PMID: 30945407 DOI: 10.1111/tra.12646] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/02/2019] [Accepted: 04/02/2019] [Indexed: 12/11/2022]
Abstract
Lysosome-related organelles (LROs) comprise a diverse group of cell type-specific, membrane-bound subcellular organelles that derive at least in part from the endolysosomal system but that have unique contents, morphologies and functions to support specific physiological roles. They include: melanosomes that provide pigment to our eyes and skin; alpha and dense granules in platelets, and lytic granules in cytotoxic T cells and natural killer cells, which release effectors to regulate hemostasis and immunity; and distinct classes of lamellar bodies in lung epithelial cells and keratinocytes that support lung plasticity and skin lubrication. The formation, maturation and/or secretion of subsets of LROs are dysfunctional or entirely absent in a number of hereditary syndromic disorders, including in particular the Hermansky-Pudlak syndromes. This review provides a comprehensive overview of LROs in humans and model organisms and presents our current understanding of how the products of genes that are defective in heritable diseases impact their formation, motility and ultimate secretion.
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Affiliation(s)
- Shanna L Bowman
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania.,Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jing Bi-Karchin
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania.,Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Linh Le
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania.,Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael S Marks
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania.,Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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12
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Waddington JL, Zhen X, O'Tuathaigh CMP. Developmental Genes and Regulatory Proteins, Domains of Cognitive Impairment in Schizophrenia Spectrum Psychosis and Implications for Antipsychotic Drug Discovery: The Example of Dysbindin-1 Isoforms and Beyond. Front Pharmacol 2020; 10:1638. [PMID: 32063853 PMCID: PMC7000454 DOI: 10.3389/fphar.2019.01638] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 12/16/2019] [Indexed: 12/19/2022] Open
Abstract
Alongside positive and negative symptomatology, deficits in working memory, attention, selective learning processes, and executive function have been widely documented in schizophrenia spectrum psychosis. These cognitive abnormalities are strongly associated with impairment across multiple function domains and are generally treatment-resistant. The DTNBP1 (dystrobrevin-binding protein-1) gene, encoding dysbindin, is considered a risk factor for schizophrenia and is associated with variation in cognitive function in both clinical and nonclinical samples. Downregulation of DTNBP1 expression in dorsolateral prefrontal cortex and hippocampal formation of patients with schizophrenia has been suggested to serve as a primary pathophysiological process. Described as a "hub," dysbindin is an important regulatory protein that is linked with multiple complexes in the brain and is involved in a wide variety of functions implicated in neurodevelopment and neuroplasticity. The expression pattern of the various dysbindin isoforms (-1A, -1B, -1C) changes depending upon stage of brain development, tissue areas and subcellular localizations, and can involve interaction with different protein partners. We review evidence describing how sequence variation in DTNBP1 isoforms has been differentially associated with schizophrenia-associated symptoms. We discuss results linking these isoform proteins, and their interacting molecular partners, with cognitive dysfunction in schizophrenia, including evidence from drosophila through to genetic mouse models of dysbindin function. Finally, we discuss preclinical evidence investigating the antipsychotic potential of molecules that influence dysbindin expression and functionality. These studies, and other recent work that has extended this approach to other developmental regulators, may facilitate identification of novel molecular pathways leading to improved antipsychotic treatments.
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Affiliation(s)
- John L Waddington
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland.,Jiangsu Key Laboratory of Translational Research & Therapy for Neuro-Psychiatric Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Translational Research & Therapy for Neuro-Psychiatric Disorders and Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Colm M P O'Tuathaigh
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland.,Medical Education Unit, School of Medicine, Brookfield Health Sciences Complex, University College Cork, Cork, Ireland
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13
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Huizing M, Malicdan MCV, Wang JA, Pri-Chen H, Hess RA, Fischer R, O'Brien KJ, Merideth MA, Gahl WA, Gochuico BR. Hermansky-Pudlak syndrome: Mutation update. Hum Mutat 2020; 41:543-580. [PMID: 31898847 DOI: 10.1002/humu.23968] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/06/2019] [Accepted: 12/26/2019] [Indexed: 12/14/2022]
Abstract
Hermansky-Pudlak syndrome (HPS) is a group of 10 autosomal recessive multisystem disorders, each defined by the deficiency of a specific gene. HPS-associated genes encode components of four ubiquitously expressed protein complexes: Adaptor protein-3 (AP-3) and biogenesis of lysosome-related organelles complex-1 (BLOC-1) through -3. All individuals with HPS exhibit albinism and a bleeding diathesis; additional features occur depending on the defective protein complex. Pulmonary fibrosis is associated with AP-3 and BLOC-3 deficiency, immunodeficiency with AP-3 defects, and gastrointestinal symptoms are more prevalent and severe in BLOC-3 deficiency. Therefore, identification of the HPS subtype is valuable for prognosis, clinical management, and treatment options. The prevalence of HPS is estimated at 1-9 per 1,000,000. Here we summarize 264 reported and novel variants in 10 HPS genes and estimate that ~333 Puerto Rican HPS subjects and ~385 with other ethnicities are reported to date. We provide pathogenicity predictions for missense and splice site variants and list variants with high minor allele frequencies. Current cellular and clinical aspects of HPS are also summarized. This review can serve as a manifest for molecular diagnostics and genetic counseling aspects of HPS.
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Affiliation(s)
- Marjan Huizing
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - May C V Malicdan
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Jennifer A Wang
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Hadass Pri-Chen
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland.,Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Richard A Hess
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Roxanne Fischer
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Kevin J O'Brien
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Melissa A Merideth
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - William A Gahl
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Bernadette R Gochuico
- Human Biochemical Genetics Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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14
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Jing R, Kong Y, Han G, Zhang J, Li K, Dong X, Yan J, Zhang H, Han J, Feng L. The Mutation of the Ap3b1 Gene Causes Uterine Hypoplasia in Pearl Mice. Reprod Sci 2020; 27:182-191. [DOI: 10.1007/s43032-019-00006-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 03/25/2019] [Indexed: 11/30/2022]
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15
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Gupta A, Utpat K, Desai U, Joshi JM. Hermansky-Pudlak syndrome with interstitial lung disease: A holistically worked up couplet. Lung India 2019; 36:345-348. [PMID: 31290422 PMCID: PMC6625230 DOI: 10.4103/lungindia.lungindia_258_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is an extremely subtile autosomal recessive disorder characterized by tyrosinase-positive oculocutaneous albinism (Ty-pos OCA), bleeding tendencies, and systemic complications associated to lysosomal dysfunction. The most grave complication of disease is interstitial lung disease (ILD) leading to irrevocable pulmonary fibrosis. Patients with HPS-1, HPS-2, and HPS-4 variants have a penchant to develop pulmonary fibrosis. The pulmonary involvement is characterised by progressive dyspnea hypoxemia respiratory failure and corpulmonale. The disease has an unfortunate prognosis with a high mortality rate and a poor quality of life. The options currently available in the therapeutic armamentarium are dismal with a dire need for opportune research. We hereby narrate an intriguing case scenario of a pair of siblings affected with this rare disorder with its associated ILD.
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Affiliation(s)
- Abhishek Gupta
- Department of Pulmonary Medicine, T. N. Medical College, B. Y. L. Nair Hospital, Mumbai, Maharashtra, India
| | - Ketaki Utpat
- Department of Pulmonary Medicine, T. N. Medical College, B. Y. L. Nair Hospital, Mumbai, Maharashtra, India
| | - Unnati Desai
- Department of Pulmonary Medicine, T. N. Medical College, B. Y. L. Nair Hospital, Mumbai, Maharashtra, India
| | - Jyotsna M Joshi
- Department of Pulmonary Medicine, T. N. Medical College, B. Y. L. Nair Hospital, Mumbai, Maharashtra, India
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16
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Plasma lipidomic profiling in murine mutants of Hermansky-Pudlak syndrome reveals differential changes in pro- and anti-atherosclerotic lipids. Biosci Rep 2019; 39:BSR20182339. [PMID: 30710063 PMCID: PMC6379572 DOI: 10.1042/bsr20182339] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/22/2019] [Accepted: 01/29/2019] [Indexed: 11/17/2022] Open
Abstract
Atherosclerosis is characterized by the accumulation of lipid-rich plaques in the arterial wall. Its pathogenesis is very complicated and has not yet been fully elucidated. It is known that dyslipidemia is a major factor in atherosclerosis. Several different Hermansky-Pudlak syndrome (HPS) mutant mice have been shown either anti-atherosclerotic or atherogenic phenotypes, which may be mainly attributed to corresponding lipid perturbation. To explore the effects of different HPS proteins on lipid metabolism and plasma lipid composition, we analyzed the plasma lipid profiles of three HPS mutant mice, pa (Hps9 -/-), ru (Hps6 -/-), ep (Hps1 -/-), and wild-type (WT) mice. In pa and ru mice, some pro-atherosclerotic lipids, e.g. ceramide (Cer) and diacylglycerol (DAG), were down-regulated whereas triacylglycerol (TAG) containing docosahexaenoic acid (DHA) (22:6) fatty acyl was up-regulated when compared with WT mice. Several pro-atherosclerotic lipids including phosphatidic acid (PA), lysophosphatidylserine (LPS), sphingomyelin (SM), and cholesterol (Cho) were up-regulated in ep mice compared with WT mice. The lipid droplets in hepatocytes showed corresponding changes in these mutants. Our data suggest that the pa mutant resembles the ru mutant in its anti-atherosclerotic effects, but the ep mutant has an atherogenic effect. Our findings may provide clues to explain why different HPS mutant mice exhibit distinct anti-atherosclerotic or atherogenic effects after being exposed to high-cholesterol diets.
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17
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18
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Osanai K. Rab38 Mutation and the Lung Phenotype. Int J Mol Sci 2018; 19:E2203. [PMID: 30060521 PMCID: PMC6122074 DOI: 10.3390/ijms19082203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 07/21/2018] [Accepted: 07/23/2018] [Indexed: 12/12/2022] Open
Abstract
Rab38 is highly expressed in alveolar type II cells, melanocytes, and platelets. These cells are specifically-differentiated cells and contain characteristic intracellular organelles called lysosome-related organelles, i.e., lamellar bodies in alveolar type II cells, melanosomes in melanocytes, and dense granules in platelets. There are Rab38-mutant rodents, i.e., chocolate mice and Ruby rats. While chocolate mice only show oculocutaneous albinism, Ruby rats show oculocutaneous albinism and prolonged bleeding time and, hence, are a rat model of Hermansky-Pudlak syndrome (HPS). Most patients with HPS suffer from fatal interstitial pneumonia by middle age. The lungs of both chocolate mice and Ruby rats show remarkably increased amounts of lung surfactant and conspicuously enlarged lysosome-related organelles, i.e., lamellar bodies, which are also characteristic of the lungs in human HPS. There are 16 mutant HPS-mouse strains, of which ten mutant genes have been identified to be causative in patients with HPS thus far. The gene products of eight of the ten genes constitute one of the three protein complexes, i.e., biogenesis of lysosome-related organelle complex-1, -2, -3 (BLOC-1, -2, -3). Patients with HPS of the mutant BLOC-3 genotype develop interstitial pneumonia. Recently, BLOC-3 has been elucidated to be a guanine nucleotide exchange factor for Rab38. Growing evidence suggests that Rab38 is an additional candidate gene of human HPS that displays the lung phenotype.
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Affiliation(s)
- Kazuhiro Osanai
- Department of Life Science, Medical Research Institute, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa 920-0293, Japan.
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa 920-0293, Japan.
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19
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Zhou Y, He CH, Yang DS, Nguyen T, Cao Y, Kamle S, Lee CM, Gochuico BR, Gahl WA, Shea BS, Lee CG, Elias JA. Galectin-3 Interacts with the CHI3L1 Axis and Contributes to Hermansky-Pudlak Syndrome Lung Disease. THE JOURNAL OF IMMUNOLOGY 2018; 200:2140-2153. [PMID: 29427412 DOI: 10.4049/jimmunol.1701442] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/04/2018] [Indexed: 01/08/2023]
Abstract
Hermansky-Pudlak syndrome (HPS) comprises a group of inherited disorders caused by mutations that alter the function of lysosome-related organelles. Pulmonary fibrosis is the major cause of morbidity and mortality in HPS-1 and HPS-4 patients. However, the mechanisms that underlie the exaggerated injury and fibroproliferative repair responses in HPS have not been adequately defined. In particular, although Galectin-3 (Gal-3) is dysregulated in HPS, its roles in the pathogenesis of HPS have not been adequately defined. In addition, although chitinase 3-like 1 (CHI3L1) and its receptors play major roles in the injury and repair responses in HPS, the ability of Gal-3 to interact with or alter the function of these moieties has not been evaluated. In this article, we demonstrate that Gal-3 accumulates in exaggerated quantities in bronchoalveolar lavage fluids, and traffics abnormally and accumulates intracellularly in lung fibroblasts and macrophages from bleomycin-treated pale ear, HPS-1-deficient mice. We also demonstrate that Gal-3 drives epithelial apoptosis when in the extracellular space, and stimulates cell proliferation and myofibroblast differentiation when accumulated in fibroblasts and M2-like differentiation when accumulated in macrophages. Biophysical and signaling evaluations also demonstrated that Gal-3 physically interacts with IL-13Rα2 and CHI3L1, and competes with TMEM219 for IL-13Rα2 binding. By doing so, Gal-3 diminishes the antiapoptotic effects of and the antiapoptotic signaling induced by CHI3L1 in epithelial cells while augmenting macrophage Wnt/β-catenin signaling. Thus, Gal-3 contributes to the exaggerated injury and fibroproliferative repair responses in HPS by altering the antiapoptotic and fibroproliferative effects of CHI3L1 and its receptor complex in a tissue compartment-specific manner.
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Affiliation(s)
- Yang Zhou
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912;
| | - Chuan Hua He
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Daniel S Yang
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Tung Nguyen
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Yueming Cao
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Suchitra Kamle
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Chang-Min Lee
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Bernadette R Gochuico
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - William A Gahl
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892
| | - Barry S Shea
- Division of Pulmonary, Critical Care and Sleep Medicine, Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI 02903; and
| | - Chun Geun Lee
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
| | - Jack A Elias
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912; .,Department of Internal Medicine, Warren Alpert Medical School of Brown University, Providence, RI 02903
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20
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Development of the Swimbladder Surfactant System and Biogenesis of Lysosome-Related Organelles Is Regulated by BLOS1 in Zebrafish. Genetics 2018; 208:1131-1146. [PMID: 29339408 DOI: 10.1534/genetics.117.300621] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 01/08/2018] [Indexed: 01/02/2023] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is a human autosomal recessive disorder that is characterized by oculocutaneous albinism and a deficiency of the platelet storage pool resulting from defective biogenesis of lysosome-related organelles (LROs). To date, 10 HPS genes have been identified, three of which belong to the octamer complex BLOC-1 (biogenesis of lysosome-related organelles complex 1). One subunit of the BLOC-1 complex, BLOS1, also participates in the BLOC-1-related complex (BORC). Due to lethality at the early embryo stage in BLOS1 knockout mice, the function of BLOS1 in the above two complexes and whether it has a novel function are unclear. Here, we generated three zebrafish mutant lines with a BLOC-1 deficiency, in which melanin and silver pigment formation was attenuated as a result of mutation of bloc1s1, bloc1s2, and dtnbp1a, suggesting that they function in the same complex. In addition, mutations of bloc1s1 and bloc1s2 caused an accumulation of clusters of lysosomal vesicles at the posterior part of the tectum, representing a BORC-specific function in zebrafish. Moreover, bloc1s1 is highly expressed in the swimbladder during postembryonic stages and is required for positively regulating the expression of the genes, which is known to govern surfactant production and lung development in mammals. Our study identified BLOS1 as a crucial regulator of the surfactant system. Thus, the zebrafish swimbladder might be an easy system to screen and study genetic modifiers that control surfactant production and homeostasis.
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21
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Wentzell R, Santoso S, Zieger B, Sandrock-Lang K. Angeborene Thrombozytenfunktionsstörungen. Hamostaseologie 2017; 36:178-86. [DOI: 10.5482/hamo-14-11-0067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 01/30/2015] [Indexed: 11/05/2022] Open
Abstract
ZusammenfassungAngeborene Thrombozytopathien können zu Blutungssymptomen unterschiedlichen Schweregrades führen, da die Thrombozyten nicht mehr ihre Funktion nach einer Gefäß-verletzung erfüllen können. In manchen Fällen sind Thrombozytopathien schwierig zu diagnostizieren und können Probleme in der Therapie und im Management verursachen. Dieser Review beschreibt den klinischen und molekulargenetischen Phänotyp der verschiedenen angeborenen Thrombozytopathien. Die angeborenen Thrombozytopathien werden entsprechend des Thrombozytendefekts eingeteilt: Rezeptordefekte (Adhäsion oder Aggregation), Sekretionsdefekte und Zytoskelettdefekte.Die am besten charakterisierten thrombozytären Rezeptordefekte sind die Glanzmann Thrombasthenie (Defekt des Integrins [uni03B1]IIb[uni03B2]3) und das Bernard-Soulier Syndrom (Defekt des GPIb/IX/V Rezeptors). Umfassende Fall-berichte über die Blutungsdiathese sowie die Untersuchung der Thrombozytenaggregation bzw. -agglutination und Rezeptorexpression von Patienten, die an der Glanzmann Thrombasthenie (GT) oder am Bernard-Soulier Syndrom (BSS) leiden, sollen diesen Review ergänzen. Darüber hinaus wird das HermanskyPudlak Syndrom (HPS) als eine bedeutende Störung der [uni03B4]-Granula Sekretion zusammen mit einer Fallbeschreibung eines Patienten, der an HPS Typ 1 leidet, beschrieben.
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22
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Abstract
Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive genetic disorder characterized by oculocutaneous albinism and a bleeding diathesis due to platelet dysfunction. More than 50% of cases worldwide are diagnosed on the Caribbean island of Puerto Rico. Genetic testing plays a growing role in diagnosis; however, not all patients with HPS have identified genetic mutations. In Puerto Rico, patients with HPS are often identified shortly after birth by their albinism, although the degree of hypopigmentation is highly variable. Ten subtypes have been described. Patients with HPS-1, HPS-2, and HPS-4 tend to develop pulmonary fibrosis in Puerto Rico; 100% of patients with HPS-1 develop HPS-PF. HPS-PF and idiopathic pulmonary fibrosis are considered similar entities (albeit with distinct causes) because both can show similar histological disease patterns. However, in contrast to idiopathic pulmonary fibrosis, HPS-PF manifests much earlier, often at 30-40 years of age. The progression of HPS-PF is characterized by the development of dyspnea and increasingly debilitating hypoxemia. No therapeutic interventions are currently approved by the U.S. Food and Drug Administration for the treatment of HPS and HPS-PF. However, the approval of two new antifibrotic drugs, pirfenidone and nintedanib, has prompted new interest in identifying drugs capable of reversing or halting the progression of HPS-PF. Thus, lung transplantation remains the only potentially life-prolonging treatment. At present, two clinical trials are recruiting patients with HPS-PF to identify biomarkers for disease progression. Advances in the diagnosis and management of these patients will require the establishment of multidisciplinary centers of excellence staffed by experts in this disease.
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23
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Michaud V, Lasseaux E, Plaisant C, Verloes A, Perdomo-Trujillo Y, Hamel C, Elcioglu NH, Leroy B, Kaplan J, Jouk PS, Lacombe D, Fergelot P, Morice-Picard F, Arveiler B. Clinico-molecular analysis of eleven patients with Hermansky-Pudlak type 5 syndrome, a mild form of HPS. Pigment Cell Melanoma Res 2017. [PMID: 28640947 DOI: 10.1111/pcmr.12608] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hermansky-Pudlak syndrome (HPS), first described in 1959, is a rare form of syndromic oculocutaneous albinism associated with bleeding diathesis and in some cases pulmonary fibrosis and granulomatous colitis. All 10 HPS types are caused by defects in vesicle trafficking of lysosome-related organelles (LRO) proteins. The HPS5 protein associates with HPS3 and HPS6 to form the biogenesis of lysosome-related organelles complex-2 (BLOC-2). Here, we report the clinical and genetic data of 11 patients with HPS-5 analyzed in our laboratory. We report 11 new pathogenic variants. The 11 patients present with ocular features that are typical for albinism, with mild hypopigmentation, and with no other major complication, apart from a tendency to bleed. HPS-5 therefore appears as a mild form of HPS, which is often clinically undistinguishable from mild oculocutaneous or ocular forms of albinism. Molecular analysis is therefore required to establish the diagnosis of this mild HPS form, which has consequences in terms of prognosis and of clinical management of the patients.
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Affiliation(s)
- Vincent Michaud
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France
| | | | | | - Alain Verloes
- Département de Génétique, Hôpital Robert Debré, Paris, France
| | | | - Christian Hamel
- Service d'Ophtalmologie, CHU de Montpellier, Montpellier, France
| | - Nursel H Elcioglu
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey.,Eastern Mediterranean University Medical School, Cyprus, Turkey
| | - Bart Leroy
- Center for Medical Genetics, Ghent University Hospital, Gent, Belgium
| | - Josseline Kaplan
- Laboratoire Génétique Moléculaire, Hôpital Necker-Enfants Malades, Paris, France
| | - Pierre-Simon Jouk
- Service Génétique Clinique, CHU de Grenoble Site La Tronche, Hôpital Couple Enfant, Grenoble, France
| | - Didier Lacombe
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
| | - Patricia Fergelot
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
| | - Fanny Morice-Picard
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Service de Dermatologie Pédiatrique, Centre de Référence Maladies Rares de la Peau, CHU de Bordeaux, Bordeaux, France
| | - Benoit Arveiler
- Service Génétique Médicale, CHU de Bordeaux, Bordeaux, France.,Unité INSERM U1211, Maladies Rares: Génétique et Métabolisme, Bordeaux, France
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24
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Sandrock-Lang K, Bartsch I, Buechele N, Koehler U, Simon-Gabriel CP, Eckenweiler M, Zieger B. Novel mutation in two brothers with Hermansky Pudlak syndrome type 3. Blood Cells Mol Dis 2017; 67:75-80. [DOI: 10.1016/j.bcmd.2017.03.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 03/03/2017] [Accepted: 03/04/2017] [Indexed: 11/26/2022]
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25
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van Liempd SM, Cabrera D, Lee FY, González E, Dell'Angelica EC, Ghiani CA, Falcon-Perez JM. BLOC-1 deficiency causes alterations in amino acid profile and in phospholipid and adenosine metabolism in the postnatal mouse hippocampus. Sci Rep 2017; 7:5231. [PMID: 28701731 PMCID: PMC5507893 DOI: 10.1038/s41598-017-05465-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 05/31/2017] [Indexed: 01/20/2023] Open
Abstract
Biogenesis of lysosome-related organelles complex-1 (BLOC-1) is a protein complex involved in the formation of endosomal tubular structures that mediates the sorting of protein cargoes to specialised compartments. In this study, we present insights into the metabolic consequences caused by BLOC-1 deficiency in pallid mice, which carry a null mutation in the Bloc1s6 gene encoding an essential component of this complex. The metabolome of the hippocampus of pallid mice was analysed using an untargeted, liquid chromatography-coupled mass spectrometric approach. After data pre-treatment, statistical analysis and pathway enrichment, we have identified 28 metabolites that showed statistically significant changes between pallid and wild-type control. These metabolites included amino acids, nucleobase-containing compounds and lysophospholipids. Interestingly, pallid mice displayed increased hippocampal levels of the neurotransmitters glutamate and N-acetyl-aspartyl-glutamic acid (NAAG) and their precursor glutamine. Expression of the sodium-coupled neutral amino acid transporter 1 (SNAT1), which transports glutamine into neurons, was also upregulated. Conversely, levels of the neurotransmitter precursors phenylalanine and tryptophan were decreased. Interestingly, many of these changes could be mapped to overlapping metabolic pathways. The observed metabolic alterations are likely to affect neurotransmission and neuronal homeostasis and in turn could mediate the memory and behavioural impairments observed in BLOC-1-deficient mice.
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Affiliation(s)
- S M van Liempd
- Metabolomics Platform. CIC bioGUNE, CIBER, Derio, 48260, Spain.
| | - D Cabrera
- Metabolomics Platform. CIC bioGUNE, CIBER, Derio, 48260, Spain
| | - F Y Lee
- Departments of Pathology & Laboratory Medicine and Psychiatry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - E González
- Metabolomics Platform. CIC bioGUNE, CIBER, Derio, 48260, Spain
| | - E C Dell'Angelica
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - C A Ghiani
- Departments of Pathology & Laboratory Medicine and Psychiatry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - J M Falcon-Perez
- Metabolomics Platform. CIC bioGUNE, CIBER, Derio, 48260, Spain. .,IKERBASQUE Research Foundation, Bilbao, Spain.
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no privacy, a Xenopus tropicalis mutant, is a model of human Hermansky-Pudlak Syndrome and allows visualization of internal organogenesis during tadpole development. Dev Biol 2017; 426:472-486. [DOI: 10.1016/j.ydbio.2016.08.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 11/19/2022]
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Osanai K, Nakase K, Sakuma T, Nishiki K, Nojiri M, Kato R, Saito M, Fujimoto Y, Mizuno S, Toga H. Exogenous gene transfer of Rab 38 small GTPase ameliorates aberrant lung surfactant homeostasis in Ruby rats. Respir Res 2017; 18:70. [PMID: 28438206 PMCID: PMC5402648 DOI: 10.1186/s12931-017-0549-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/11/2017] [Indexed: 11/25/2022] Open
Abstract
Background Rab38 small GTPase regulates intracellular transport in melanocytes and alveolar type II epithelial cells. Ruby rats carrying Rab38 and other gene mutations exhibit oculocutaneous albinism, bleeding diathesis, and hence, are a rat model of human Hermansky-Pudlak syndrome (HPS). We previously showed that Long Evans Cinnamon (LEC) rats, one strain of the Ruby rats, developed aberrant lung surfactant homeostasis with remarkably enlarged lamellar bodies in alveolar type II cells. Methods A replication-deficient recombinant adenovirus expressing rat Rab38 (Ad-Rab38) was constructed. Alveolar type II cells were isolated from the LEC rats and tested for lung surfactant phosphatidylcholine secretion. The rats were also examined whether exogenous expression of Ad- Rab38 could rescue the altered lung surfactant homeostasis in the lungs. Results Isolated type II cells infected with Ad-Rab38 exhibited improved secretion patterns of [3H]phosphatidylcholine, i.e. increased basal hyposecretion and decreased agonist-induced hypersecretion. Endobronchial administration of Ad-Rab38 improved the morphology of type II cells and lamellar bodies, reducing their sizes close to those of wild-type rats. The increased amounts of phosphatidylcholine and surfactant protein B in the lamellar body fractions were decreased in the Ad-Rab38 infected lungs. Conclusions These results provide strong evidence that the aberrant lung surfactant homeostasis in the LEC rats is caused by Rab38 deficit, and suggest that endobronchial delivery of the responsive transgene could be an effective method to ameliorate the abnormal lung phenotype in the animal model of HPS.
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Affiliation(s)
- Kazuhiro Osanai
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan.
| | - Keisuke Nakase
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Takashi Sakuma
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Kazuaki Nishiki
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Masafumi Nojiri
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Ryo Kato
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Masatoshi Saito
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Yuki Fujimoto
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Shiro Mizuno
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Hirohisa Toga
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
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Gioria M, Pasini ME, Berruti G. Dynamic of contribution of UBPy-sorted cargo to acrosome biogenesis: effects of its derailment in a mouse model of globozoospermia, the infertile Vps54 (L967Q) mutant. Cell Tissue Res 2017; 369:413-427. [DOI: 10.1007/s00441-017-2592-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 02/21/2017] [Indexed: 12/14/2022]
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Bariana TK, Ouwehand WH, Guerrero JA, Gomez K. Dawning of the age of genomics for platelet granule disorders: improving insight, diagnosis and management. Br J Haematol 2016; 176:705-720. [PMID: 27984638 DOI: 10.1111/bjh.14471] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Inherited disorders of platelet granules are clinically heterogeneous and their prevalence is underestimated because most patients do not undergo a complete diagnostic work-up. The lack of a genetic diagnosis limits the ability to tailor management, screen family members, aid with family planning, predict clinical progression and detect serious consequences, such as myelofibrosis, lung fibrosis and malignancy, in a timely manner. This is set to change with the introduction of high throughput sequencing (HTS) as a routine clinical diagnostic test. HTS diagnostic tests are now available, affordable and allow parallel screening of DNA samples for variants in all of the 80 known bleeding, thrombotic and platelet genes. Increased genetic diagnosis and curation of variants is, in turn, improving our understanding of the pathobiology and clinical course of inherited platelet disorders. Our understanding of the genetic causes of platelet granule disorders and the regulation of granule biogenesis is a work in progress and has been significantly enhanced by recent genomic discoveries from high-powered genome-wide association studies and genome sequencing projects. In the era of whole genome and epigenome sequencing, new strategies are required to integrate multiple sources of big data in the search for elusive, novel genes underlying granule disorders.
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Affiliation(s)
- Tadbir K Bariana
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free London NHS Foundation Trust, London, UK.,Department of Haematology, University College London Cancer Institute, London, UK.,Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Willem H Ouwehand
- Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,NHS Blood and Transplant, Cambridge Biomedical Campus, Cambridge, UK.,NIHR BioResource, Cambridge University Hospitals, Cambridge Biomedical Campus, Cambridge, UK.,Human Genetics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK
| | - Jose A Guerrero
- Department of Haematology, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,NHS Blood and Transplant, Cambridge Biomedical Campus, Cambridge, UK
| | - Keith Gomez
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free London NHS Foundation Trust, London, UK
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Abstract
Platelet dense granules (DGs) are membrane bound compartments that store polyphosphate and small molecules such as ADP, ATP, Ca2+, and serotonin. The release of DG contents plays a central role in platelet aggregation to form a hemostatic plug. Accordingly, congenital deficiencies in the biogenesis of platelet DGs underlie human genetic disorders that cause storage pool disease and manifest with prolonged bleeding. DGs belong to a family of lysosome-related organelles, which also includes melanosomes, the compartments where the melanin pigments are synthesized. These organelles share several characteristics including an acidic lumen and, at least in part, the molecular machinery involved in their biogenesis. As a result, many genes affect both DG and melanosome biogenesis and the corresponding patients present not only with bleeding but also with oculocutaneous albinism. The identification and characterization of such genes has been instrumental in dissecting the pathways responsible for organelle biogenesis. Because the study of melanosome biogenesis has advanced more rapidly, this knowledge has been extrapolated to explain how DGs are produced. However, some progress has recently been made in studying platelet DG biogenesis directly in megakaryocytes and megakaryocytoid cells. DGs originate from an endosomal intermediate compartment, the multivesicular body. Maturation and differentiation into a DG begins when newly synthesized DG-specific proteins are delivered from early/recycling endosomal compartments. The machinery that orchestrates this vesicular trafficking is composed of a combination of both ubiquitous and cell type-specific proteins. Here, we review the current knowledge on DG biogenesis. In particular, we focus on the individual human and murine genes encoding the molecular machinery involved in this process and how their deficiencies result in disease.
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Affiliation(s)
- Andrea L Ambrosio
- a Department of Biochemistry and Molecular Biology , Colorado State University , Fort Collins , Colorado , USA
| | - Santiago M Di Pietro
- a Department of Biochemistry and Molecular Biology , Colorado State University , Fort Collins , Colorado , USA
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31
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Zheng X, Li Y, zhao R, Yan F, Ma Y, Zhao L, Qiao H. xCT deficiency induces autophagy via endoplasmic reticulum stress activated p38-mitogen-activated protein kinase and mTOR in sut melanocytes. Eur J Cell Biol 2016; 95:175-81. [DOI: 10.1016/j.ejcb.2016.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/17/2016] [Accepted: 03/21/2016] [Indexed: 12/11/2022] Open
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Lou Z, Casali P, Xu Z. Regulation of B Cell Differentiation by Intracellular Membrane-Associated Proteins and microRNAs: Role in the Antibody Response. Front Immunol 2015; 6:537. [PMID: 26579118 PMCID: PMC4620719 DOI: 10.3389/fimmu.2015.00537] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/07/2015] [Indexed: 12/17/2022] Open
Abstract
B cells are central to adaptive immunity and their functions in antibody responses are exquisitely regulated. As suggested by recent findings, B cell differentiation is mediated by intracellular membrane structures (including endosomes, lysosomes, and autophagosomes) and protein factors specifically associated with these membranes, including Rab7, Atg5, and Atg7. These factors participate in vesicle formation/trafficking, signal transduction and induction of gene expression to promote antigen presentation, class switch DNA recombination (CSR)/somatic hypermutation (SHM), and generation/maintenance of plasma cells and memory B cells. Their expression is induced in B cells activated to differentiate and further fine-tuned by immune-modulating microRNAs, which coordinates CSR/SHM, plasma cell differentiation, and memory B cell differentiation. These short non-coding RNAs would individually target multiple factors associated with the same intracellular membrane compartments and collaboratively target a single factor in addition to regulating AID and Blimp-1. These, together with regulation of microRNA biogenesis and activities by endosomes and autophagosomes, show that intracellular membranes and microRNAs, two broadly relevant cell constituents, play important roles in balancing gene expression to specify B cell differentiation processes for optimal antibody responses.
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Affiliation(s)
- Zheng Lou
- Department of Microbiology and Immunology, School of Medicine, The University of Texas Health Science Center , San Antonio, TX , USA
| | - Paolo Casali
- Department of Microbiology and Immunology, School of Medicine, The University of Texas Health Science Center , San Antonio, TX , USA
| | - Zhenming Xu
- Department of Microbiology and Immunology, School of Medicine, The University of Texas Health Science Center , San Antonio, TX , USA
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Zhou Y, He CH, Herzog EL, Peng X, Lee CM, Nguyen TH, Gulati M, Gochuico BR, Gahl WA, Slade ML, Lee CG, Elias JA. Chitinase 3-like-1 and its receptors in Hermansky-Pudlak syndrome-associated lung disease. J Clin Invest 2015; 125:3178-92. [PMID: 26121745 DOI: 10.1172/jci79792] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 05/21/2015] [Indexed: 12/20/2022] Open
Abstract
Hermansky-Pudlak syndrome (HPS) comprises a group of inherited disorders caused by mutations that alter the function of lysosome-related organelles. Pulmonary fibrosis is the major cause of morbidity and mortality in patients with subtypes HPS-1 and HPS-4, which both result from defects in biogenesis of lysosome-related organelle complex 3 (BLOC-3). The prototypic chitinase-like protein chitinase 3-like-1 (CHI3L1) plays a protective role in the lung by ameliorating cell death and stimulating fibroproliferative repair. Here, we demonstrated that circulating CHI3L1 levels are higher in HPS patients with pulmonary fibrosis compared with those who remain fibrosis free, and that these levels associate with disease severity. Using murine HPS models, we also determined that these animals have a defect in the ability of CHI3L1 to inhibit epithelial apoptosis but exhibit exaggerated CHI3L1-driven fibroproliferation, which together promote HPS fibrosis. These divergent responses resulted from differences in the trafficking and effector functions of two CHI3L1 receptors. Specifically, the enhanced sensitivity to apoptosis was due to abnormal localization of IL-13Rα2 as a consequence of dysfunctional BLOC-3-dependent membrane trafficking. In contrast, the fibrosis was due to interactions between CHI3L1 and the receptor CRTH2, which trafficked normally in BLOC-3 mutant HPS. These data demonstrate that CHI3L1-dependent pathways exacerbate pulmonary fibrosis and suggest CHI3L1 as a potential biomarker for pulmonary fibrosis progression and severity in HPS.
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Abstract
In this issue of Blood, Meng et al and Sharda et al use the Hermansky-Pudlak syndrome (HPS) as a model to show that adenosine 5′-diphosphate (ADP) released by dense granules serves as an autocrine signal to potentiate platelet release of α-granule and lysosome cargo and protein disulfide isomerase (PDI), all of which serve to stabilize thrombus formation.
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Guo T, Wang X, Qu Y, Yin Y, Jing T, Zhang Q. Megakaryopoiesis and platelet production: insight into hematopoietic stem cell proliferation and differentiation. Stem Cell Investig 2015; 2:3. [PMID: 27358871 DOI: 10.3978/j.issn.2306-9759.2015.02.01] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 02/06/2015] [Indexed: 12/12/2022]
Abstract
Hematopoietic stem cells (HSCs) undergo successive lineage commitment steps to generate megakaryocytes (MKs) in a process referred to as megakaryopoiesis. MKs undergo a unique differentiation process involving endomitosis to eventually produce platelets. Many transcription factors participate in the regulation of this complex progress. Chemokines and other factors in the microenvironment where megakaryopoiesis and platelet production occur play vital roles in the regulation of HSC lineage commitment and MK maturation; among these factors, thrombopoietin (TPO) is the most important. Endomitosis is a vital process of MK maturation, and granules that are formed in MKs are important for platelet function. Proplatelets are firstly generated from mature MKs and then become platelets. The proplatelet production process was verified by novel studies that revealed that the mechanism is partially regulated by the invaginated membrane system (IMS), microtubules and Rho GTPases. The extracellular matrices (ECMs) and shear stress also affect and regulate the process while the mature MKs migrate from the marrow to the sub-endothelium region near the venous sinusoids leading to the release of platelets into the circulation. This review describes the entire process of megakaryopoiesis in detail, illustrates both the transcriptional and microenvironmental regulation of MKs and provides insight into platelet biogenesis.
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Affiliation(s)
- Tianyu Guo
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
| | - Xuejun Wang
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
| | - Yigong Qu
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
| | - Yu Yin
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
| | - Tao Jing
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
| | - Qing Zhang
- 1 State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China ; 2 Research Institute of Sun Yat-Sen University in Shenzhen, Shenzhen 518057, China
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Hao Z, Wei L, Feng Y, Chen X, Du W, Ma J, Zhou Z, Chen L, Li W. Impaired maturation of large dense core vesicles in muted-deficient adrenal chromaffin cells. J Cell Sci 2015; 128:1365-74. [DOI: 10.1242/jcs.161414] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The large dense-core vesicle (LDCV), a type of lysosome-related organelle, is involved in the secretion of hormones and neuropeptides in specialized secretory cells. The granin family is a driving force in LDCV biogenesis, but the machinery for granin sorting to this biogenesis pathway is largely unknown. The mu mutant mouse, which carries a spontaneous null mutation on the Muted gene (also known as Bloc1s5) that encodes a subunit of lysosome-related organelles complex-1 (BLOC-1), is a mouse model of Hermansky-Pudlak syndrome. We here found that LDCVs were enlarged in mu adrenal chromaffin cells. Chromogranin A (CgA) was increased in mu adrenals and muted-knockdown cells. The increased CgA in mu mice was likely due to the failure of its sorting-out, which impairs LDCV maturation and docking. In mu chromaffin cells, the size of readily releasable pool and the vesicle release frequency were reduced. Our studies suggest that the muted protein is involved in the sorting-out of CgA during the biogenesis of LDCVs.
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Regulation of mRNA abundance by polypyrimidine tract-binding protein-controlled alternate 5' splice site choice. PLoS Genet 2014; 10:e1004771. [PMID: 25375251 PMCID: PMC4222953 DOI: 10.1371/journal.pgen.1004771] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 09/22/2014] [Indexed: 11/19/2022] Open
Abstract
Alternative splicing (AS) provides a potent mechanism for increasing protein diversity and modulating gene expression levels. How alternate splice sites are selected by the splicing machinery and how AS is integrated into gene regulation networks remain important questions of eukaryotic biology. Here we report that polypyrimidine tract-binding protein 1 (Ptbp1/PTB/hnRNP-I) controls alternate 5' and 3' splice site (5'ss and 3'ss) usage in a large set of mammalian transcripts. A top scoring event identified by our analysis was the choice between competing upstream and downstream 5'ss (u5'ss and d5'ss) in the exon 18 of the Hps1 gene. Hps1 is essential for proper biogenesis of lysosome-related organelles and loss of its function leads to a disease called type 1 Hermansky-Pudlak Syndrome (HPS). We show that Ptbp1 promotes preferential utilization of the u5'ss giving rise to stable mRNAs encoding a full-length Hps1 protein, whereas bias towards d5'ss triggered by Ptbp1 down-regulation generates transcripts susceptible to nonsense-mediated decay (NMD). We further demonstrate that Ptbp1 binds to pyrimidine-rich sequences between the u5'ss and d5'ss and activates the former site rather than repressing the latter. Consistent with this mechanism, u5'ss is intrinsically weaker than d5'ss, with a similar tendency observed for other genes with Ptbp1-induced u5'ss bias. Interestingly, the brain-enriched Ptbp1 paralog Ptbp2/nPTB/brPTB stimulated the u5'ss utilization but with a considerably lower efficiency than Ptbp1. This may account for the tight correlation between Hps1 with Ptbp1 expression levels observed across mammalian tissues. More generally, these data expand our understanding of AS regulation and uncover a post-transcriptional strategy ensuring co-expression of a subordinate gene with its master regulator through an AS-NMD tracking mechanism.
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Sánchez-Guiu I, Torregrosa JM, Velasco F, Antón AI, Lozano ML, Vicente V, Rivera J. Hermansky-Pudlak syndrome. Overview of clinical and molecular features and case report of a new HPS-1 variant. Hamostaseologie 2014; 34:301-9. [PMID: 25117010 DOI: 10.5482/hamo-14-06-0024] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/04/2014] [Indexed: 12/30/2022] Open
Abstract
Hermansky-Pudlak syndrome (HPS) is a rare, autosomal recessive disorder affecting lysosome-related organelles (LRO), including dense platelet granules. HPS causes oculocutaneous hypopigmentation, bleeding diathesis and granulomatous colitis or pulmonary fibrosis. To date, there is no curative treatment and the clinical management depends on the severity of symptoms. A prompt diagnosis of HPS patients could improve their quality of life and clinical management. However, the absence of a specific platelet function test, the wide molecular heterogeneity, and the lack of phenotype-genotype correlations hamper the rapid diagnosis. Nine subtypes of HPS have been identified as a result of mutations in nine genes that codify for proteins involved in formation and shuttle of the LRO. The molecular characterization of patients and knowledge derived from animal models of HPS contribute to the understanding of biogenesis and function of the LRO. This paper describes a patient with a novel homozygous nonsense mutation causing HPS and provides a review of the literature focusing on recent advances in the molecular characterization and physiopathology of HPS.
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Affiliation(s)
| | | | | | | | | | | | - J Rivera
- José Rivera, PhD., Centro Regional de Hemodonación, C/ Ronda de Garay s/n, Murcia, 30003, Spain, Tel. +34/968/34 19 90; Fax +34/968/261 91, E-mail:
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Wei AH, He X, Li W. Hypopigmentation in Hermansky-Pudlak syndrome. J Dermatol 2014; 40:325-9. [PMID: 23668540 DOI: 10.1111/1346-8138.12025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Accepted: 09/20/2012] [Indexed: 11/28/2022]
Abstract
Hermansky-Pudlak syndrome (HPS) is characterized by oculocutaneous albinism, bleeding tendency, and ceroid deposition which often leads to death in midlife. Currently, nine genes have been identified as causative for HPS in humans. Hypopigmentation is the prominent feature of HPS, attributable to the disrupted biogenesis of melanosome, a member of the lysosome-related organelle (LRO) family. Current understanding of the cargo transporting mechanisms into the melanosomes expands our knowledge of the pathogenesis of hypopigmentation in HPS patients.
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Affiliation(s)
- Ai-Hua Wei
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
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40
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Kim YJ, Maizel A, Chen X. Traffic into silence: endomembranes and post-transcriptional RNA silencing. EMBO J 2014; 33:968-80. [PMID: 24668229 PMCID: PMC4193931 DOI: 10.1002/embj.201387262] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
microRNAs (miRNAs) and small interfering RNAs (siRNAs) are small RNAs that repress gene expression at the post-transcriptional level in plants and animals. Small RNAs guide Argonaute-containing RNA-induced silencing complexes to target RNAs in a sequence-specific manner, resulting in mRNA deadenylation followed by exonucleolytic decay, mRNA endonucleolytic cleavage, or translational inhibition. Although our knowledge of small RNA biogenesis, turnover, and mechanisms of action has dramatically expanded in the past decade, the subcellular location of small RNA-mediated RNA silencing still needs to be defined. In contrast to the prevalent presumption that RNA silencing occurs in the cytosol, emerging evidence reveals connections between the endomembrane system and small RNA activities in plants and animals. Here, we summarize the work that uncovered this link between small RNAs and endomembrane compartments and present an overview of the involvement of the endomembrane system in various aspects of RNA silencing. We propose that the endomembrane system is an integral component of RNA silencing that has been long overlooked and predict that a marriage between cell biology and RNA biology holds the key to a full understanding of post-transcriptional gene regulation by small RNAs.
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Affiliation(s)
- Yun Ju Kim
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology University of California, Riverside, CA, USA
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Machlus KR, Thon JN, Italiano JE. Interpreting the developmental dance of the megakaryocyte: a review of the cellular and molecular processes mediating platelet formation. Br J Haematol 2014; 165:227-36. [PMID: 24499183 DOI: 10.1111/bjh.12758] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Platelets are essential for haemostasis, and thrombocytopenia (platelet counts <150 × 10(9) /l) is a major clinical problem encountered across a number of conditions, including immune thrombocytopenic purpura, myelodysplastic syndromes, chemotherapy, aplastic anaemia, human immunodeficiency virus infection, complications during pregnancy and delivery, and surgery. Circulating blood platelets are specialized cells that function to prevent bleeding and minimize blood vessel injury. Platelets circulate in their quiescent form, and upon stimulation, activate to release their granule contents and spread on the affected tissue to create a physical barrier that prevents blood loss. The current model of platelet formation states that large progenitor cells in the bone marrow, called megakaryocytes, release platelets by extending long, branching processes, designated proplatelets, into sinusoidal blood vessels. This review will focus on different factors that impact megakaryocyte development, proplatelet formation and platelet release. It will highlight recent studies on thrombopoeitin-dependent megakaryocyte maturation, endomitosis and granule formation, cytoskeletal contributions to proplatelet formation, the role of apoptosis, and terminal platelet formation and release.
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Affiliation(s)
- Kellie R Machlus
- Hematology Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
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Tornieri K, Zlatic SA, Mullin AP, Werner E, Harrison R, L'hernault SW, Faundez V. Vps33b pathogenic mutations preferentially affect VIPAS39/SPE-39-positive endosomes. Hum Mol Genet 2013; 22:5215-28. [PMID: 23918659 DOI: 10.1093/hmg/ddt378] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mutations in Vps33 isoforms cause pigment dilution in mice (Vps33a, buff) and Drosophila (car) and the neurogenic arthrogryposis, renal dysfunction and cholestasis syndrome in humans (ARC1, VPS33B). The later disease is also caused by mutations in VIPAS39, (Vps33b interacting protein, apical-basolateral polarity regulator, SPE-39 homolog; ARC2), a protein that interacts with the HOmotypic fusion and Protein Sorting (HOPS) complex, a tether necessary for endosome-lysosome traffic. These syndromes offer insight into fundamental endosome traffic processes unique to metazoans. However, the molecular and cellular mechanisms underlying these mutant phenotypes remain poorly understood. Here we investigate interactions of wild-type and disease-causing mutations in VIPAS39/SPE-39 and Vps33b by yeast two hybrid, immunoprecipitation and quantitative fluorescent microscopy. We find that although few mutations prevent interaction between VIPAS39/SPE-39 and Vps33b, some mutants fragment VIPAS39/SPE-39-positive endosomes, but all mutants alter the subcellular localization of Vps33b to VIPAS39/SPE-39-positive endosomes. Our data suggest that the ARC syndrome may result through impaired VIPAS39/SPE-39 and Vps33b-dependent endosomal maturation or fusion.
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Abstract
Gray platelet syndrome (GPS) is an inherited bleeding disorder associated with macrothrombocytopenia and α-granule-deficient platelets. GPS has been linked to loss of function mutations in NEABL2 (neurobeachin-like 2), and we describe here a murine GPS model, the Nbeal2(-/-) mouse. As in GPS, Nbeal2(-/-) mice exhibit splenomegaly, macrothrombocytopenia, and a deficiency of platelet α-granules and their cargo, including von Willebrand factor (VWF), thrombospondin-1, and platelet factor 4. The platelet α-granule membrane protein P-selectin is expressed at 48% of wild-type levels and externalized upon platelet activation. The presence of P-selectin and normal levels of VPS33B and VPS16B in Nbeal2(-/-) platelets suggests that NBEAL2 acts independently of VPS33B/VPS16B at a later stage of α-granule biogenesis. Impaired Nbeal2(-/-) platelet function was shown by flow cytometry, platelet aggregometry, bleeding assays, and intravital imaging of laser-induced arterial thrombus formation. Microscopic analysis detected marked abnormalities in Nbeal2(-/-) bone marrow megakaryocytes, which when cultured showed delayed maturation, decreased survival, decreased ploidy, and developmental abnormalities, including abnormal extracellular distribution of VWF. Our results confirm that α-granule secretion plays a significant role in platelet function, and they also indicate that abnormal α-granule formation in Nbeal2(-/-) mice has deleterious effects on megakaryocyte survival, development, and platelet production.
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Abstract
Genetic disorders of lymphocyte cytotoxicity predispose patients to hemophagocytic lymphohistiocytosis (HLH). Reduced lymphocyte cytotoxicity has been demonstrated in Hermansky-Pudlak syndrome type 2 (HPS2), but only a single patient was reported who developed HLH. Because that patient also carried a potentially contributing heterozygous RAB27A mutation, the risk for HLH in HPS2 remains unclear. We analyzed susceptibility to HLH in the pearl mouse model of HPS2. After infection with lymphocytic choriomeningitis virus, pearl mice developed all key features of HLH, linked to impaired virus control caused by a moderate defect in CTL cytotoxicity in vivo. However, in contrast to perforin-deficient mice, the disease was transient, and all mice fully recovered and controlled the infection. An additional heterozygous Rab27a mutation did not aggravate the cytotoxicity defect or disease parameters. In the largest survey of 22 HPS2 patients covering 234 patient years, we identified only 1 additional patient with HLH and 2 with incomplete transient HLH-like episodes, although cytotoxicity or degranulation was impaired in all 16 patients tested. HPS2 confers a risk for HLH that is lower than in Griscelli or Chediak-Higashi syndrome, probably because of a milder defect in cytotoxicity. Preemptive hematopoietic stem cell transplantation does not appear justified in HPS2.
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Israels SJ, Rand ML. What we have learned from inherited platelet disorders. Pediatr Blood Cancer 2013; 60 Suppl 1:S2-7. [PMID: 23109117 DOI: 10.1002/pbc.24345] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 08/30/2012] [Indexed: 11/09/2022]
Abstract
Identifying the molecular basis of inherited platelet disorders has contributed to our understanding of normal platelet physiology. Many of these conditions are rare, but close observation of clinical and laboratory phenotype, and subsequent identification of the abnormal protein and mutated gene, have provided us with unique opportunities to examine specific aspects of platelet biogenesis and function. Phenotype-genotype association studies are providing a detailed understanding of the structure and function of platelet membrane receptors, the biogenesis and release of platelet granules, and the assembly of the cytoskeleton. Genetic polymorphisms contributing to decreased or increased platelet adhesion and activation may translate into increased clinical risks for bleeding or thrombosis. More recently, genome wide association studies have identified new genes contributing to the variation in normal platelet function.
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Affiliation(s)
- Sara J Israels
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, Canada.
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Wei AH, Li W. Hermansky-Pudlak syndrome: pigmentary and non-pigmentary defects and their pathogenesis. Pigment Cell Melanoma Res 2012; 26:176-92. [DOI: 10.1111/pcmr.12051] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 11/16/2012] [Indexed: 10/27/2022]
Affiliation(s)
| | - Wei Li
- State Key Laboratory of Molecular Developmental Biology; Institute of Genetics & Developmental Biology; Chinese Academy of Sciences; Beijing; China
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Bultema JJ, Di Pietro SM. Cell type-specific Rab32 and Rab38 cooperate with the ubiquitous lysosome biogenesis machinery to synthesize specialized lysosome-related organelles. Small GTPases 2012; 4:16-21. [PMID: 23247405 PMCID: PMC3620096 DOI: 10.4161/sgtp.22349] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Lysosome-related organelles (LROs) exist in specialized cells to serve specific functions and typically co-exist with conventional lysosomes. The biogenesis of LROs is known to utilize much of the common protein machinery used in the transport of integral membrane proteins to lysosomes. Consequently, an outstanding question in the field has been how specific cargoes are trafficked to LROs instead of lysosomes, particularly in cells that simultaneously produce both organelles. One LRO, the melanosome, is responsible for the production of the pigment melanin and has long been used as a model system to study the formation of specialized LROs. Importantly, melanocytes, where melanosomes are synthesized, are a cell type that also produces lysosomes and must therefore segregate traffic to each organelle. Two small GTPases, Rab32 and Rab38, are key proteins in the biogenesis of melanosomes and were recently shown to redirect the ubiquitous machinery—BLOC-2, AP-1 and AP-3—to traffic specialized cargoes to melanosomes in melanocytes. In addition, the study revealed Rab32 and Rab38 have both redundant and unique roles in the trafficking of melanin-producing enzymes and overall melanosome biogenesis. Here we review these findings, integrate them with previous knowledge on melanosome biogenesis and discuss their implications for biogenesis of other LROs.
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Affiliation(s)
- Jarred J Bultema
- Department of Biochemistry and Molecular Biology; Colorado State University; Fort Collins, CO USA
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Spanò S, Galán JE. A Rab32-dependent pathway contributes to Salmonella typhi host restriction. Science 2012; 338:960-3. [PMID: 23162001 DOI: 10.1126/science.1229224] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Unlike other Salmonellae, the intracellular bacterial human pathogen Salmonella Typhi exhibits strict host specificity. The molecular bases for this restriction are unknown. Here we found that the expression of a single type III secretion system effector protein from broad-host Salmonella Typhimurium allowed Salmonella Typhi to survive and replicate within macrophages and tissues from mice, a nonpermissive host. This effector proteolytically targeted Rab32, which controls traffic to lysosome-related organelles in conjunction with components of the biogenesis of lysosome-related organelle complexes (BLOCs). RNA interference-mediated depletion of Rab32 or of an essential component of a BLOC complex was sufficient to allow S. Typhi to survive within mouse macrophages. Furthermore, S. Typhi was able to survive in macrophages from mice defective in BLOC components.
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Affiliation(s)
- Stefania Spanò
- Department of Microbial Pathogenesis, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA
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