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Lee JJ, Wang T, Wiggins K, Lu PN, Underwood C, Ochenkowska K, Samarut E, Pollard LM, Flanagan-Steet H, Steet R. Dysregulated lysosomal exocytosis drives protease-mediated cartilage pathogenesis in multiple lysosomal disorders. iScience 2024; 27:109293. [PMID: 38495824 PMCID: PMC10940929 DOI: 10.1016/j.isci.2024.109293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 12/20/2023] [Accepted: 02/16/2024] [Indexed: 03/19/2024] Open
Abstract
The classic view of the lysosome as a static recycling center has been replaced with one of a dynamic and mobile hub of metabolic regulation. This revised view raises new questions about how dysfunction of this organelle causes pathology in inherited lysosomal disorders. Here we provide evidence for increased lysosomal exocytosis in the developing cartilage of three lysosomal disease zebrafish models with distinct etiologies. Dysregulated exocytosis was linked to altered cartilage development, increased activity of multiple cathepsin proteases, and cathepsin- and TGFβ-mediated pathogenesis in these models. Moreover, inhibition of cathepsin activity or direct blockade of exocytosis with small molecule modulators improved the cartilage phenotypes, reinforcing a connection between excessive extracellular protease activity and cartilage pathogenesis. This study highlights the pathogenic consequences in early cartilage development arising from uncontrolled release of lysosomal enzymes via exocytosis, and suggests that pharmacological enhancement of this process could be detrimental during tissue development.
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Affiliation(s)
- Jen-Jie Lee
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Tong Wang
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Kali Wiggins
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Po Nien Lu
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Christina Underwood
- Biochemical Genetics Laboratory, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Katarzyna Ochenkowska
- Research Center, Centre hospitalier de l’Université de Montréal (CHUM), Montreal, Canada
- Department of Neuroscience, Université de Montréal, Montréal, Canada
| | - Eric Samarut
- Research Center, Centre hospitalier de l’Université de Montréal (CHUM), Montreal, Canada
- Department of Neuroscience, Université de Montréal, Montréal, Canada
| | - Laura M. Pollard
- Biochemical Genetics Laboratory, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | | | - Richard Steet
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
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2
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Liu D, Jiang Z, Deng L, Li H, Jiang H. Identification of an α-l-iduronidase (IDUA) M1T mutation in a Chinese family with autosomal recessive mucopolysaccharidosis I. Ann N Y Acad Sci 2023; 1526:114-125. [PMID: 37347427 DOI: 10.1111/nyas.15016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/23/2023]
Abstract
Mucopolysaccharidoses (MPS) are a group of rare congenital metabolic disorders caused by the deficiency or low activity of enzymes required for glycosaminoglycans degradation. Mutations in the α-l-iduronidase gene (IDUA) are associated with mucopolysaccharidosis type I (MPS I). Our study here aims to identify an MPS-related gene mutation in a typical patient with MPS and to further explore the possible pathogenic mechanism. We identified a homozygous c. 2T>C (p.M1T) change in IDUA as the pathogenic mutation in this individual (both parents were identified as carriers of the mutation), with IDUA enzyme activity significantly decreased. We further established an MPS I-related zebrafish model using IDUA-specific morpholino (MO) to suppress gene expression, and found that IDUA-MO zebrafish exhibited characteristic disease phenotypes with deficiency of IDUA. Transcriptome profiling of zebrafish larvae revealed 487 genes that were significantly altered when IDUA was depleted. TP53 signaling and LC3/GABARAP family protein-mediated autophagy were significantly upregulated in IDUA-MO zebrafish larvae. Moreover, leukotriene A4 hydrolase-mediated arachidonic acid metabolism was also upregulated. Introduction of wild-type human IDUA mRNA rescued developmental defects and aberrant signaling in IDUA-MO zebrafish larvae. In conclusion, our study provides potential therapeutic targets for the treatment of MPS I.
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Affiliation(s)
- Dan Liu
- Eye Center of Xiangya Hospital and Hunan Key Laboratory of Ophthalmology, Central South University, Changsha, China
| | - Zhongjing Jiang
- Department of Spine Surgery and Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Linhua Deng
- Department of Spine Surgery and Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Haibo Li
- Eye Center of Xiangya Hospital and Hunan Key Laboratory of Ophthalmology, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Haibo Jiang
- Eye Center of Xiangya Hospital and Hunan Key Laboratory of Ophthalmology, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
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3
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Klaver EJ, Dukes-Rimsky L, Kumar B, Xia ZJ, Dang T, Lehrman MA, Angel P, Drake RR, Freeze HH, Steet R, Flanagan-Steet H. Protease-dependent defects in N-cadherin processing drive PMM2-CDG pathogenesis. JCI Insight 2021; 6:153474. [PMID: 34784297 PMCID: PMC8783681 DOI: 10.1172/jci.insight.153474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022] Open
Abstract
The genetic bases for the congenital disorders of glycosylation (CDG) continue to expand, but how glycosylation defects cause patient phenotypes remains largely unknown. Here, we combined developmental phenotyping and biochemical studies in a potentially new zebrafish model (pmm2sa10150) of PMM2-CDG to uncover a protease-mediated pathogenic mechanism relevant to craniofacial and motility phenotypes in mutant embryos. Mutant embryos had reduced phosphomannomutase activity and modest decreases in N-glycan occupancy as detected by matrix-assisted laser desorption ionization mass spectrometry imaging. Cellular analyses of cartilage defects in pmm2sa10150 embryos revealed a block in chondrogenesis that was associated with defective proteolytic processing, but seemingly normal N-glycosylation, of the cell adhesion molecule N-cadherin. The activities of the proconvertases and matrix metalloproteinases responsible for N-cadherin maturation were significantly altered in pmm2sa10150 mutant embryos. Importantly, pharmacologic and genetic manipulation of proconvertase activity restored matrix metalloproteinase activity, N-cadherin processing, and cartilage pathology in pmm2sa10150 embryos. Collectively, these studies demonstrate in CDG that targeted alterations in protease activity create a pathogenic cascade that affects the maturation of cell adhesion proteins critical for tissue development.
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Affiliation(s)
- Elsenoor J Klaver
- Complex Carbohydrate Research Center, University of Georgia, Athens, United States of America
| | - Lynn Dukes-Rimsky
- Research Department, Greenwood Genetic Center, Greenwood, United States of America
| | - Brijesh Kumar
- Research Department, Greenwood Genetic Center, Greenwood, United States of America
| | - Zhi-Jie Xia
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, United States of America
| | - Tammie Dang
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, United States of America
| | - Mark A Lehrman
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, United States of America
| | - Peggi Angel
- Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, United States of America
| | - Richard R Drake
- Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, United States of America
| | - Hudson H Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, United States of America
| | - Richard Steet
- Research Department, Greenwood Genetic Center, Greenwood, United States of America
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4
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Marí-Beffa M, Mesa-Román AB, Duran I. Zebrafish Models for Human Skeletal Disorders. Front Genet 2021; 12:675331. [PMID: 34490030 PMCID: PMC8418114 DOI: 10.3389/fgene.2021.675331] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/08/2021] [Indexed: 12/17/2022] Open
Abstract
In 2019, the Nosology Committee of the International Skeletal Dysplasia Society provided an updated version of the Nosology and Classification of Genetic Skeletal Disorders. This is a reference list of recognized diseases in humans and their causal genes published to help clinician diagnosis and scientific research advances. Complementary to mammalian models, zebrafish has emerged as an interesting species to evaluate chemical treatments against these human skeletal disorders. Due to its versatility and the low cost of experiments, more than 80 models are currently available. In this article, we review the state-of-art of this “aquarium to bedside” approach describing the models according to the list provided by the Nosology Committee. With this, we intend to stimulate research in the appropriate direction to efficiently meet the actual needs of clinicians under the scope of the Nosology Committee.
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Affiliation(s)
- Manuel Marí-Beffa
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain.,Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Andalusian Centre for Nanomedicine and Biotechnology-BIONAND, Málaga, Spain
| | - Ana B Mesa-Román
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain
| | - Ivan Duran
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain.,Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Andalusian Centre for Nanomedicine and Biotechnology-BIONAND, Málaga, Spain
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5
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Remes A, Arif R, Franz M, Jungmann A, Zaradzki M, Puehler T, Md MBH, Frey N, Karck M, Kallenbach K, Hecker M, Müller OJ, Wagner AH. AAV-mediated AP-1 decoy oligonucleotide expression inhibits aortic elastolysis in a mouse model of marfan syndrome. Cardiovasc Res 2021; 117:2459-2473. [PMID: 33471064 DOI: 10.1093/cvr/cvab012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 03/02/2019] [Accepted: 01/12/2021] [Indexed: 01/05/2023] Open
Abstract
AIMS Marfan syndrome is one of the most common inherited disorders of connective tissue caused by fibrillin-1 mutations, characterized by enhanced transcription factor AP-1 DNA binding activity and subsequently abnormally increased expression and activity of matrix-metalloproteinases (MMPs). We aimed to establish a novel adeno-associated virus (AAV)-based strategy for long-term expression of an AP-1 neutralising RNA hairpin (hp) decoy oligonucleotide (dON) in the aorta to prevent aortic elastolysis in a murine model of Marfan syndrome. METHODS AND RESULTS Using fibrillin-1 hypomorphic mice (mgR/mgR), aortic grafts from young (9 weeks old) donor mgR/mgR mice were transduced ex vivo with AAV vectors and implanted as infrarenal aortic interposition grafts in mgR/mgR mice. Grafts were explanted after 30 days. For in vitro studies isolated primary aortic smooth muscle cells from mgR/mgR mice were used. Elastica-van-Giesson staining visualized elastolysis, ROS production was assessed using DHE staining. RNA F.I.S.H. verified AP-1 hp dON generation in the ex vivo transduced aortic tissue. MMP expression and activity were assessed by western blotting and immunoprecipitation combined with zymography.Transduction resulted in stable therapeutic dON expression in endothelial and smooth muscle cells. MMP expression and activity, ROS formation as well as expression of monocyte chemoattractant protein-1 were significantly reduced. Monocyte graft infiltration declined and the integrity of the elastin architecture was maintained. RNAseq analyzis confirmed the beneficial effect of AP-1 neutralisation on the pro-inflammatory environment in smooth muscle cells. CONCLUSIONS This novel approach protects from deterioration of aortic stability by sustained delivery of nucleic acids-based therapeutics and further elucidated how to interfere with the mechanism of elastolysis. TRANSLATIONAL PERSPECTIVE This study provides a novel single treatment option to achieve long-term expression of a transcription factor AP-1 neutralising decoy oligonucleotide in the aorta of mgR/mgR mice with the potential to prevent life-threatening elastolysis and aortic complications.
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Affiliation(s)
- Anca Remes
- Department of Internal Medicine III, University of Kiel, and University Hospital Schleswig-Holstein, Kiel, and German Centre for Cardiovascular Research, Partner Site, Hamburg/Kiel/Lübeck, Germany.,Institute of Physiology and Pathophysiology, Heidelberg University, Germany
| | - Rawa Arif
- Department of Cardiac Surgery, University Hospital Heidelberg, Germany
| | - Maximilian Franz
- Department of Cardiac Surgery, University Hospital Heidelberg, Germany
| | | | - Marcin Zaradzki
- Department of Cardiac Surgery, University Hospital Heidelberg, Germany
| | - Thomas Puehler
- Department of Cardiac and Vascular Surgery, University of Kiel and University Hospital Schleswig-Holstein, Kiel, Germany
| | | | - Norbert Frey
- Department of Internal Medicine III, University of Kiel, and University Hospital Schleswig-Holstein, Kiel, and German Centre for Cardiovascular Research, Partner Site, Hamburg/Kiel/Lübeck, Germany.,Internal Medicine III, University Hospital Heidelberg, Germany
| | - Matthias Karck
- Department of Cardiac Surgery, University Hospital Heidelberg, Germany
| | | | - Markus Hecker
- Institute of Physiology and Pathophysiology, Heidelberg University, Germany
| | - Oliver J Müller
- Department of Internal Medicine III, University of Kiel, and University Hospital Schleswig-Holstein, Kiel, and German Centre for Cardiovascular Research, Partner Site, Hamburg/Kiel/Lübeck, Germany
| | - Andreas H Wagner
- Institute of Physiology and Pathophysiology, Heidelberg University, Germany
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6
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Lu PN, Moreland T, Christian CJ, Lund TC, Steet RA, Flanagan-Steet H. Inappropriate cathepsin K secretion promotes its enzymatic activation driving heart and valve malformation. JCI Insight 2020; 5:133019. [PMID: 33055423 PMCID: PMC7605527 DOI: 10.1172/jci.insight.133019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 09/16/2020] [Indexed: 01/12/2023] Open
Abstract
Although congenital heart defects (CHDs) represent the most common birth defect, a comprehensive understanding of disease etiology remains unknown. This is further complicated since CHDs can occur in isolation or as a feature of another disorder. Analyzing disorders with associated CHDs provides a powerful platform to identify primary pathogenic mechanisms driving disease. Aberrant localization and expression of cathepsin proteases can perpetuate later-stage heart diseases, but their contribution toward CHDs is unclear. To investigate the contribution of cathepsins during cardiovascular development and congenital disease, we analyzed the pathogenesis of cardiac defects in zebrafish models of the lysosomal storage disorder mucolipidosis II (MLII). MLII is caused by mutations in the GlcNAc-1-phosphotransferase enzyme (Gnptab) that disrupt carbohydrate-dependent sorting of lysosomal enzymes. Without Gnptab, lysosomal hydrolases, including cathepsin proteases, are inappropriately secreted. Analyses of heart development in gnptab-deficient zebrafish show cathepsin K secretion increases its activity, disrupts TGF-β–related signaling, and alters myocardial and valvular formation. Importantly, cathepsin K inhibition restored normal heart and valve development in MLII embryos. Collectively, these data identify mislocalized cathepsin K as an initiator of cardiac disease in this lysosomal disorder and establish cathepsin inhibition as a viable therapeutic strategy. Mislocalized cathepsin K promotes cardiac disease in a zebrafish model of the lysosomal disorder mucolipidosis II and can be targeted by cathespin inhibition.
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Affiliation(s)
- Po-Nien Lu
- Greenwood Genetic Center, J.C. Self Research Institute, Greenwood, South Carolina, USA
| | - Trevor Moreland
- Greenwood Genetic Center, J.C. Self Research Institute, Greenwood, South Carolina, USA
| | - Courtney J Christian
- Biochemistry, Cell and Developmental Biology, Emory University Laney Graduate School, Atlanta, Georgia, USA
| | - Troy C Lund
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Richard A Steet
- Greenwood Genetic Center, J.C. Self Research Institute, Greenwood, South Carolina, USA
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7
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Mucolipidoses Overview: Past, Present, and Future. Int J Mol Sci 2020; 21:ijms21186812. [PMID: 32957425 PMCID: PMC7555117 DOI: 10.3390/ijms21186812] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/13/2020] [Accepted: 09/14/2020] [Indexed: 12/12/2022] Open
Abstract
Mucolipidosis II and III (ML II/III) are caused by a deficiency of uridine-diphosphate N-acetylglucosamine: lysosomal-enzyme-N-acetylglucosamine-1-phosphotransferase (GlcNAc-1-phosphotransferase, EC2.7.8.17), which tags lysosomal enzymes with a mannose 6-phosphate (M6P) marker for transport to the lysosome. The process is performed by a sequential two-step process: first, GlcNAc-1-phosphotransferase catalyzes the transfer of GlcNAc-1-phosphate to the selected mannose residues on lysosomal enzymes in the cis-Golgi network. The second step removes GlcNAc from lysosomal enzymes by N-acetylglucosamine-1-phosphodiester α-N-acetylglucosaminidase (uncovering enzyme) and exposes the mannose 6-phosphate (M6P) residues in the trans-Golgi network, in which the enzymes are targeted to the lysosomes by M6Preceptors. A deficiency of GlcNAc-1-phosphotransferase causes the hypersecretion of lysosomal enzymes out of cells, resulting in a shortage of multiple lysosomal enzymes within lysosomes. Due to a lack of GlcNAc-1-phosphotransferase, the accumulation of cholesterol, phospholipids, glycosaminoglycans (GAGs), and other undegraded substrates occurs in the lysosomes. Clinically, ML II and ML III exhibit quite similar manifestations to mucopolysaccharidoses (MPSs), including specific skeletal deformities known as dysostosis multiplex and gingival hyperplasia. The life expectancy is less than 10 years in the severe type, and there is no definitive treatment for this disease. In this review, we have described the updated diagnosis and therapy on ML II/III.
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8
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Naumchik BM, Gupta A, Flanagan-Steet H, Steet RA, Cathey SS, Orchard PJ, Lund TC. The Role of Hematopoietic Cell Transplant in the Glycoprotein Diseases. Cells 2020; 9:cells9061411. [PMID: 32517081 PMCID: PMC7348849 DOI: 10.3390/cells9061411] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/02/2020] [Accepted: 06/02/2020] [Indexed: 12/12/2022] Open
Abstract
The glycoprotein disorders are a group of lysosomal storage diseases (α-mannosidosis, aspartylglucosaminuria, β-mannosidosis, fucosidosis, galactosialidosis, sialidosis, mucolipidosis II, mucolipidosis III, and Schindler Disease) characterized by specific lysosomal enzyme defects and resultant buildup of undegraded glycoprotein substrates. This buildup causes a multitude of abnormalities in patients including skeletal dysplasia, inflammation, ocular abnormalities, liver and spleen enlargement, myoclonus, ataxia, psychomotor delay, and mild to severe neurodegeneration. Pharmacological treatment options exist through enzyme replacement therapy (ERT) for a few, but therapies for this group of disorders is largely lacking. Hematopoietic cell transplant (HCT) has been explored as a potential therapeutic option for many of these disorders, as HCT introduces functional enzyme-producing cells into the bone marrow and blood along with the engraftment of healthy donor cells in the central nervous system (presumably as brain macrophages or a type of microglial cell). The outcome of HCT varies widely by disease type. We report our institutional experience with HCT as well as a review of the literature to better understand HCT and outcomes for the glycoprotein disorders.
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Affiliation(s)
- Brianna M. Naumchik
- Division of Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN 55455, USA; (B.M.N.); (A.G.); (P.J.O.)
| | - Ashish Gupta
- Division of Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN 55455, USA; (B.M.N.); (A.G.); (P.J.O.)
| | | | - Richard A. Steet
- Greenwood Genetic Center, Greenwood, SC 29646, USA; (H.F.-S.); (R.A.S.); (S.S.C.)
| | - Sara S. Cathey
- Greenwood Genetic Center, Greenwood, SC 29646, USA; (H.F.-S.); (R.A.S.); (S.S.C.)
| | - Paul J. Orchard
- Division of Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN 55455, USA; (B.M.N.); (A.G.); (P.J.O.)
| | - Troy C. Lund
- Division of Pediatric Blood and Marrow Transplant, University of Minnesota, Minneapolis, MN 55455, USA; (B.M.N.); (A.G.); (P.J.O.)
- Correspondence: ; Tel.: +612-625-4185
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9
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Ates KM, Wang T, Moreland T, Veeranan-Karmegam R, Ma M, Jeter C, Anand P, Wenzel W, Kim HG, Wolfe LA, Stephen J, Adams DR, Markello T, Tifft CJ, Settlage R, Gahl WA, Gonsalvez GB, Malicdan MC, Flanagan-Steet H, Pan YA. Deficiency in the endocytic adaptor proteins PHETA1/2 impairs renal and craniofacial development. Dis Model Mech 2020; 13:dmm041913. [PMID: 32152089 PMCID: PMC7272357 DOI: 10.1242/dmm.041913] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 02/27/2020] [Indexed: 12/20/2022] Open
Abstract
A critical barrier in the treatment of endosomal and lysosomal diseases is the lack of understanding of the in vivo functions of the putative causative genes. We addressed this by investigating a key pair of endocytic adaptor proteins, PH domain-containing endocytic trafficking adaptor 1 and 2 (PHETA1/2; also known as FAM109A/B, Ses1/2, IPIP27A/B), which interact with the protein product of OCRL, the causative gene for Lowe syndrome. Here, we conducted the first study of PHETA1/2 in vivo, utilizing the zebrafish system. We found that impairment of both zebrafish orthologs, pheta1 and pheta2, disrupted endocytosis and ciliogenesis in renal tissues. In addition, pheta1/2 mutant animals exhibited reduced jaw size and delayed chondrocyte differentiation, indicating a role in craniofacial development. Deficiency of pheta1/2 resulted in dysregulation of cathepsin K, which led to an increased abundance of type II collagen in craniofacial cartilages, a marker of immature cartilage extracellular matrix. Cathepsin K inhibition rescued the craniofacial phenotypes in the pheta1/2 double mutants. The abnormal renal and craniofacial phenotypes in the pheta1/2 mutant animals were consistent with the clinical presentation of a patient with a de novo arginine (R) to cysteine (C) variant (R6C) of PHETA1. Expressing the patient-specific variant in zebrafish exacerbated craniofacial deficits, suggesting that the R6C allele acts in a dominant-negative manner. Together, these results provide insights into the in vivo roles of PHETA1/2 and suggest that the R6C variant is contributory to the pathogenesis of disease in the patient.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Kristin M Ates
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA 24016, USA
| | - Tong Wang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Trevor Moreland
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | | | - Manxiu Ma
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA 24016, USA
| | - Chelsi Jeter
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Priya Anand
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Wolfgang Wenzel
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Hyung-Goo Kim
- Neurological Disorder Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Doha, Qatar
| | - Lynne A Wolfe
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Joshi Stephen
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David R Adams
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Thomas Markello
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cynthia J Tifft
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Robert Settlage
- Advanced Research Computing Unit, Division of Information Technology, Virginia Tech, Blacksburg, VA 24060, USA
| | - William A Gahl
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
- National Institutes of Health Undiagnosed Diseases Program, National Institutes of Health, Bethesda, MD 20892, USA
| | - Graydon B Gonsalvez
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - May Christine Malicdan
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
- National Institutes of Health Undiagnosed Diseases Program, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Y Albert Pan
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA 24016, USA
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24060, USA
- Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
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10
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Zhang T, Peterson RT. Modeling Lysosomal Storage Diseases in the Zebrafish. Front Mol Biosci 2020; 7:82. [PMID: 32435656 PMCID: PMC7218095 DOI: 10.3389/fmolb.2020.00082] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 04/08/2020] [Indexed: 12/13/2022] Open
Abstract
Lysosomal storage diseases (LSDs) are a family of 70 metabolic disorders characterized by mutations in lysosomal proteins that lead to storage material accumulation, multiple-organ pathologies that often involve neurodegeneration, and early mortality in a significant number of patients. Along with the necessity for more effective therapies, there exists an unmet need for further understanding of disease etiology, which could uncover novel pathways and drug targets. Over the past few decades, the growth in knowledge of disease-associated pathways has been facilitated by studies in model organisms, as advancements in mutagenesis techniques markedly improved the efficiency of model generation in mammalian and non-mammalian systems. In this review we highlight non-mammalian models of LSDs, focusing specifically on the zebrafish, a vertebrate model organism that shares remarkable genetic and metabolic similarities with mammals while also conferring unique advantages such as optical transparency and amenability toward high-throughput applications. We examine published zebrafish LSD models and their reported phenotypes, address organism-specific advantages and limitations, and discuss recent technological innovations that could provide potential solutions.
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Affiliation(s)
- T Zhang
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT, United States
| | - R T Peterson
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT, United States
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11
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Barnes JW, Aarnio-Peterson M, Norris J, Haskins M, Flanagan-Steet H, Steet R. Upregulation of Sortilin, a Lysosomal Sorting Receptor, Corresponds with Reduced Bioavailability of Latent TGFβ in Mucolipidosis II Cells. Biomolecules 2020; 10:biom10050670. [PMID: 32357547 PMCID: PMC7277838 DOI: 10.3390/biom10050670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 04/14/2020] [Accepted: 04/20/2020] [Indexed: 12/14/2022] Open
Abstract
Mucolipidosis II (ML-II) is a lysosomal disease caused by defects in the carbohydrate-dependent sorting of soluble hydrolases to lysosomes. Altered growth factor signaling has been identified as a contributor to the phenotypes associated with ML-II and other lysosomal disorders but an understanding of how these signaling pathways are affected is still emerging. Here, we investigated transforming growth factor beta 1 (TGFβ1) signaling in the context of ML-II patient fibroblasts, observing decreased TGFβ1 signaling that was accompanied by impaired TGFβ1-dependent wound closure. We found increased intracellular latent TGFβ1 complexes, caused by reduced secretion and stable localization in detergent-resistant lysosomes. Sortilin, a sorting receptor for hydrolases and TGFβ-related cytokines, was upregulated in ML-II fibroblasts as well as GNPTAB-null HeLa cells, suggesting a mechanism for inappropriate lysosomal targeting of TGFβ. Co-expression of sortilin and TGFβ in HeLa cells resulted in reduced TGFβ1 secretion. Elevated sortilin levels correlated with normal levels of cathepsin D in ML-II cells, consistent with a compensatory role for this receptor in lysosomal hydrolase targeting. Collectively, these data support a model whereby sortilin upregulation in cells with lysosomal storage maintains hydrolase sorting but suppresses TGFβ1 secretion through increased lysosomal delivery. These findings highlight an unexpected link between impaired lysosomal sorting and altered growth factor bioavailability.
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Affiliation(s)
- Jarrod W Barnes
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | - Joy Norris
- Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - Mark Haskins
- Emeritus Professor, Pathology and Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104-6051, USA
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12
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He SW, Du X, Wang GH, Wang JJ, Xie B, Gu QQ, Zhang M, Gu HJ. Identification and characterization of a cathepsin K homologue that interacts with pathogen bacteria in black rockfish, Sebastes schlegelii. FISH & SHELLFISH IMMUNOLOGY 2020; 98:499-507. [PMID: 32001355 DOI: 10.1016/j.fsi.2020.01.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/20/2020] [Accepted: 01/24/2020] [Indexed: 06/10/2023]
Abstract
Cathepsin K belongs to the family of cysteine cathepsins. It is well known that the cysteine cathepsins participate in various physiological processes and host immune defense in mammals. However, in teleost fish, the function of cathepsin K is very limited. In the present study, a cathepsin K homologue (SsCTSK) from the teleost black rockfish (Sebastes schlegelii) was identified and examined at expression and functional levels. In silico analysis showed that three domains, including signal peptide, cathepsin propeptide inhibitor I29 domain, and functional domain Pept_C1, are existed in SsCTSK. SsCTSK also possesses a peptidase domain with three catalytically essential residues (Cys25, His162 and Asn183). Phylogenetic profiling indicated that SsCTSK was evolutionally close to the cathepsin K of other teleost fish. Expression of SsCTSK occurred in multiple tissues and was induced by bacterial infection. Purified recombinant SsCTSK (rSsCTSK) exhibited apparent maximal peptidase activity at 45 °C, and its enzymatic activity was remarkably declined in the presence of the cathepsin inhibitor E-64. Moreover, rSsCTSK possesses the ability to bind with PAMPs and bacteria. Finally, knockdown of SsCTSK expression facilitated bacterial invasion in black rockfish. Collectively, these results indicated that SsCTSK functions as a cysteine protease and may serves as a target for pathogen manipulation of host defense system.
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Affiliation(s)
- Shu-Wen He
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Xue Du
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Guang-Hua Wang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Jing-Jing Wang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Bing Xie
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Qin-Qin Gu
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Min Zhang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.
| | - Han-Jie Gu
- Institute of Tropical Biosciences and Biotechnology, Hainan Academy of Tropical Agricultural Resource, CATAS, Haikou, 571101, China; Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources, Haikou, 571101, China.
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13
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Soliman SA, Kamal BM, Abd-Elhafeez HH. Cellular Invasion and Matrix Degradation, a Different Type of Matrix-Degrading Cells in the Cartilage of Catfish ( Clarias gariepinus) and Japanese Quail Embryos ( Coturnix coturnix japonica). MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:1283-1292. [PMID: 31583991 DOI: 10.1017/s1431927619014892] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We previously studied the phenomena of the mesenchymal cell-dependent mode of cartilage growth in quail and catfish. Thus, we selected the two cartilage models in which mesenchymal cells participate in their growth. In such models, cartilage degradation occurred to facilitate cellular invasion. The studies do not explain the nature of the cartilage degrading cells. The current study aims to explore the nature of the cartilage-degrading cells using transmission electron microscopy (TEM) and immunohistochemistry. Samples of cartilage have been isolated from the air-breathing organ of catfish and the cartilage of the prospective occipital bone of quail embryos. Samples have been processed for TEM and immunohistochemistry. We found that two different cell types are involved in cartilage degradation; the macrophage in the cartilage of catfish and mesenchymal cells in the cartilage of the quail. Areas of cellular invasion in both catfish cartilage and quail embryo cartilage had an immunological affinity for MMP-9. In catfish, cartilage-degrading cells had identical morphological features of macrophages, whereas in quail embryos, cartilage-degrading cells were mesenchymal-like cells which had cell processes rich in vesicles and expressed CD117. Further study should consider the role of macrophage and mesenchymal cells during cartilage degradation. This could be valuable to be applied to remove the defective cartilage matrix formed in osteoarthritic patients to improve cartilage repair strategies.
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Affiliation(s)
- Soha A Soliman
- Department of Histology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt
| | - Basma Mohamed Kamal
- Anatomy and Embryology Department, Faculty of Veterinary Medicine, Sadat-City University, Sadat City, Egypt
| | - Hanan H Abd-Elhafeez
- Department of Anatomy, Embryology and Histology, Assiut University, Assiut, 71526, Egypt
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14
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Flanagan-Steet H, Christian C, Lu PN, Aarnio-Peterson M, Sanman L, Archer-Hartmann S, Azadi P, Bogyo M, Steet RA. TGF-ß Regulates Cathepsin Activation during Normal and Pathogenic Development. Cell Rep 2019. [PMID: 29539424 PMCID: PMC6247414 DOI: 10.1016/j.celrep.2018.02.066] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cysteine cathepsins play roles during development and disease beyond their function in lysosomal protein turnover. Here, we leverage a fluorescent activity-based probe (ABP), BMV109, to track cysteine cathepsins in normal and diseased zebrafish embryos. Using this probe in a model of mucolipidosis II, we show that loss of carbohydrate-dependent lysosomal sorting alters the activity of several cathepsin proteases. The data support a pathogenic mechanism where TGF-β signals enhance the proteolytic processing of pro-Ctsk by modulating the expression of chondroitin 4-sulfate (C4-S). In MLII, elevated C4-S corresponds with TGF-β-mediated increases in chst11 expression. Inhibiting chst11 impairs the proteolytic activation of Ctsk and alleviates the MLII phenotypes. These findings uncover a regulatory loop between TGF-β signaling and Ctsk activation that is altered in the context of lysosomal disease. This work highlights the power of ABPs to identify mechanisms underlying pathogenic development in living animals. Chondroitin sulfate is a known regulator of cathepsin protease activity. Flanagan-Steet et al. identify a positive feedback mechanism whereby cathepsins secreted from chondrocytes upon loss of lysosomal targeting activate TGF-β signaling in developing cartilage. This increased signaling, in turn, stimulates chondroitin-4 sulfation and enhances cathepsin activity.
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Affiliation(s)
| | - Courtney Christian
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30606, USA
| | - Po-Nien Lu
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30606, USA
| | | | - Laura Sanman
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5324, USA
| | | | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30606, USA
| | - Matthew Bogyo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305-5324, USA
| | - Richard A Steet
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30606, USA
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15
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Köse S, Aerts Kaya F, Kuşkonmaz B, Uçkan Çetinkaya D. Characterization of mesenchymal stem cells in mucolipidosis type II (I-cell disease). ACTA ACUST UNITED AC 2019; 43:171-178. [PMID: 31320815 PMCID: PMC6620033 DOI: 10.3906/biy-1902-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Mucolipidosis type II (ML-II, I-cell disease) is a fatal inherited lysosomal storage disease caused by a deficiency of the enzyme N-acetylglucosamine-1-phosphotransferase. A characteristic skeletal phenotype is one of the many clinical manifestations of ML-II. Since the mechanisms underlying these skeletal defects in ML-II are not completely understood, we hypothesized that a defect in osteogenic differentiation of ML-II bone marrow mesenchymal stem cells (BM-MSCs) might be responsible for this skeletal phenotype. Here, we assessed and characterized the cellular phenotype of BM-MSCs from a ML-II patient before (BBMT) and after BM transplantation (ABMT), and we compared the results with BM-MSCs from a carrier and a healthy donor. Morphologically, we did not observe differences in ML-II BBMT and ABMT or carrier MSCs in terms of size or granularity. Osteogenic differentiation was not markedly affected by disease or carrier status. Adipogenic differentiation was increased in BBMT ML-II MSCs, but chondrogenic differentiation was decreased in both BBMT and ABMT ML-II MSCs. Immunophenotypically no significant differences were observed between the samples. Interestingly, the proliferative capacity of BBMT and ABMT ML-II MSCs was increased in comparison to MSCs from age-matched healthy donors. These data suggest that MSCs are not likely to cause the skeletal phenotype observed in ML-II, but they may contribute to the pathogenesis of ML-II as a result of lysosomal storage-induced pathology.
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Affiliation(s)
- Sevil Köse
- Department of Medical Biology and Genetics, Faculty of Medicine, Atılım University, Ankara, Turkey.,Center for Stem Cell Research and Development (PEDI-STEM), Hacettepe University, Ankara, Turkey
| | - Fatima Aerts Kaya
- Center for Stem Cell Research and Development (PEDI-STEM), Hacettepe University, Ankara, Turkey.,Department of Stem Cell Sciences, Graduate School of Health Sciences, Hacettepe University, Ankara, Turkey
| | - Barış Kuşkonmaz
- Center for Stem Cell Research and Development (PEDI-STEM), Hacettepe University, Ankara, Turkey.,BMT Unit, Department of Pediatric Hematology, Hacettepe University Children's Hospital, Ankara, Turkey
| | - Duygu Uçkan Çetinkaya
- Center for Stem Cell Research and Development (PEDI-STEM), Hacettepe University, Ankara, Turkey.,Department of Stem Cell Sciences, Graduate School of Health Sciences, Hacettepe University, Ankara, Turkey.,BMT Unit, Department of Pediatric Hematology, Hacettepe University Children's Hospital, Ankara, Turkey
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16
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Wang P, Mazrier H, Caverly Rae J, Raj K, Giger U. A GNPTAB nonsense variant is associated with feline mucolipidosis II (I-cell disease). BMC Vet Res 2018; 14:416. [PMID: 30591066 PMCID: PMC6307278 DOI: 10.1186/s12917-018-1728-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/30/2018] [Indexed: 11/15/2022] Open
Abstract
Background Mucolipidosis II (ML II; I-cell disease) is caused by a deficiency of N-acetylglucosamine-1-phosphotransferase (GNPTAB; EC 2.7.8.17), which leads to a failure to internalize acid hydrolases into lysosomes for proper catabolism of various substances. This is an autosomal recessive lysosomal storage disease and causes severe progressive neuropathy and oculoskeletal dysfunction in humans (OMIM 252500). A naturally occurring disease model has been reported in juvenile domestic cats (OMIA 001248–9685) with clinical signs similar to human patients. We investigated the molecular genetic basis of ML II in a colony of affected cats by sequencing the coding and regulatory regions of GNPTAB from affected and clinically healthy related and unrelated domestic cats and compared the sequences to the published feline genome sequence (NCBI-RefSeq accession no. XM_003989173.4, Gene ID: 101100231). Results All affected cats were homozygous for a single base substitution (c.2644C > T) in exon 13 of GNPTAB. This variant results in a premature stop codon (p.Gln882*) which predicts severe truncation and complete dysfunction of the GNPTAB enzyme. About 140 GNPTAB variants have been described in human ML II patients, with 41.3% nonsense/missense mutations, nine occurring in the same gene region as in this feline model. Restriction fragment length polymorphism and allelic discrimination real-time polymerase chain reaction assays accurately differentiated between clear, asymptomatic carriers and homozygous affected cats. Conclusion Molecular genetic characterization advances this large animal model of ML II for use to further define the pathophysiology of the disease and evaluate novel therapeutic approaches for this fatal lysosomal storage disease in humans. Electronic supplementary material The online version of this article (10.1186/s12917-018-1728-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ping Wang
- Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Hamutal Mazrier
- Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jessica Caverly Rae
- Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Karthik Raj
- Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Urs Giger
- Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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17
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Beck SV, Räsänen K, Ahi EP, Kristjánsson BK, Skúlason S, Jónsson ZO, Leblanc CA. Gene expression in the phenotypically plastic Arctic charr (Salvelinus alpinus): A focus on growth and ossification at early stages of development. Evol Dev 2018; 21:16-30. [PMID: 30474913 PMCID: PMC9285049 DOI: 10.1111/ede.12275] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Gene expression during development shapes the phenotypes of individuals. Although embryonic gene expression can have lasting effects on developmental trajectories, few studies consider the role of maternal effects, such as egg size, on gene expression. Using qPCR, we characterize relative expression of 14 growth and/or skeletal promoting genes across embryonic development in Arctic charr (Salvelinus alpinus). We test to what extent their relative expression is correlated with egg size and size at early life‐stages within the study population. We predict smaller individuals to have higher expression of growth and skeletal promoting genes, due to less maternal resources (i.e., yolk) and prioritization of energy toward ossification. We found expression levels to vary across developmental stages and only three genes (Mmp9, Star, and Sgk1) correlated with individual size at a given developmental stage. Contrary to our hypothesis, expression of Mmp9 and Star showed a non‐linear relationship with size (at post fertilization and hatching, respectively), whilst Sgk1 was higher in larger embryos at hatching. Interestingly, these genes are also associated with craniofacial divergence of Arctic charr morphs. Our results indicate that early life‐stage variation in gene expression, concomitant to maternal effects, can influence developmental plasticity and potentially the evolution of resource polymorphism in fishes.
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Affiliation(s)
- Samantha V Beck
- Department of Aquaculture and Fish Biology, Hólar University College, Háskólinn á Hólum, Sauðárkrókur, Iceland.,Institute of Life- and Environmental Sciences, University of Iceland, Reykjavík, Iceland
| | - Katja Räsänen
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Ehsan P Ahi
- Institute of Life- and Environmental Sciences, University of Iceland, Reykjavík, Iceland.,Institute of Zoology, University of Graz, Universitätsplatz 2, Graz, Austria
| | - Bjarni K Kristjánsson
- Department of Aquaculture and Fish Biology, Hólar University College, Háskólinn á Hólum, Sauðárkrókur, Iceland
| | - Skúli Skúlason
- Department of Aquaculture and Fish Biology, Hólar University College, Háskólinn á Hólum, Sauðárkrókur, Iceland
| | - Zophonías O Jónsson
- Institute of Life- and Environmental Sciences, University of Iceland, Reykjavík, Iceland
| | - Camille A Leblanc
- Department of Aquaculture and Fish Biology, Hólar University College, Háskólinn á Hólum, Sauðárkrókur, Iceland
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18
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Kondo Y, Fu J, Wang H, Hoover C, McDaniel JM, Steet R, Patra D, Song J, Pollard L, Cathey S, Yago T, Wiley G, Macwana S, Guthridge J, McGee S, Li S, Griffin C, Furukawa K, James JA, Ruan C, McEver RP, Wierenga KJ, Gaffney PM, Xia L. Site-1 protease deficiency causes human skeletal dysplasia due to defective inter-organelle protein trafficking. JCI Insight 2018; 3:121596. [PMID: 30046013 PMCID: PMC6124414 DOI: 10.1172/jci.insight.121596] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/08/2018] [Indexed: 01/18/2023] Open
Abstract
Site-1 protease (S1P), encoded by MBTPS1, is a serine protease in the Golgi. S1P regulates lipogenesis, endoplasmic reticulum (ER) function, and lysosome biogenesis in mice and in cultured cells. However, how S1P differentially regulates these diverse functions in humans has been unclear. In addition, no human disease with S1P deficiency has been identified. Here, we report a pediatric patient with an amorphic and a severely hypomorphic mutation in MBTPS1. The unique combination of these mutations results in a frequency of functional MBTPS1 transcripts of approximately 1%, a finding that is associated with skeletal dysplasia and elevated blood lysosomal enzymes. We found that the residually expressed S1P is sufficient for lipid homeostasis but not for ER and lysosomal functions, especially in chondrocytes. The defective S1P function specifically impairs activation of the ER stress transducer BBF2H7, leading to ER retention of collagen in chondrocytes. S1P deficiency also causes abnormal secretion of lysosomal enzymes due to partial impairment of mannose-6-phosphate-dependent delivery to lysosomes. Collectively, these abnormalities lead to apoptosis of chondrocytes and lysosomal enzyme-mediated degradation of the bone matrix. Correction of an MBTPS1 variant or reduction of ER stress mitigated collagen-trafficking defects. These results define a new congenital human skeletal disorder and, more importantly, reveal that S1P is particularly required for skeletal development in humans. Our findings may also lead to new therapies for other genetic skeletal diseases, as ER dysfunction is common in these disorders.
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Affiliation(s)
- Yuji Kondo
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Jianxin Fu
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA.,Jiangsu Institute of Hematology, MOH Key Laboratory of Thrombosis and Hemostasis, Collaborative Innovation Center of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | | | - Christopher Hoover
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - J Michael McDaniel
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Richard Steet
- Complex Carbohydrate Research Center, University of Georgia, Georgia, Athens, USA
| | - Debabrata Patra
- Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jianhua Song
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Laura Pollard
- Greenwood Genetic Center, Greenwood, South Carolina, USA
| | - Sara Cathey
- Greenwood Genetic Center, Greenwood, South Carolina, USA
| | - Tadayuki Yago
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Graham Wiley
- Division of Genomics and Data Sciences, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Susan Macwana
- Division of Genomics and Data Sciences, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Joel Guthridge
- Division of Genomics and Data Sciences, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Samuel McGee
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | | | - Courtney Griffin
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Koichi Furukawa
- Department of Biochemistry II, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Judith A James
- Division of Genomics and Data Sciences, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Changgeng Ruan
- Jiangsu Institute of Hematology, MOH Key Laboratory of Thrombosis and Hemostasis, Collaborative Innovation Center of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Rodger P McEver
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | - Patrick M Gaffney
- Division of Genomics and Data Sciences, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Lijun Xia
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA.,Jiangsu Institute of Hematology, MOH Key Laboratory of Thrombosis and Hemostasis, Collaborative Innovation Center of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
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19
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Santos-Ledo A, Garcia-Macia M, Campbell PD, Gronska M, Marlow FL. Kinesin-1 promotes chondrocyte maintenance during skeletal morphogenesis. PLoS Genet 2017; 13:e1006918. [PMID: 28715414 PMCID: PMC5536392 DOI: 10.1371/journal.pgen.1006918] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/31/2017] [Accepted: 07/11/2017] [Indexed: 01/03/2023] Open
Abstract
During skeletal morphogenesis diverse mechanisms are used to support bone formation. This can be seen in the bones that require a cartilage template for their development. In mammals the cartilage template is removed, but in zebrafish the cartilage template persists and the bone mineralizes around the cartilage scaffold. Remodeling of unmineralized cartilage occurs via planar cell polarity (PCP) mediated cell rearrangements that contribute to lengthening of elements; however, the mechanisms that maintain the chondrocyte template that supports perichondral ossification remain unclear. We report double mutants disrupting two zebrafish kinesin-I genes (hereafter kif5Blof) that we generated using CRISPR/Cas9 mutagenesis. We show that zygotic Kif5Bs have a conserved function in maintaining muscle integrity, and are required for cartilage remodeling and maintenance during craniofacial morphogenesis by a PCP-distinct mechanism. Further, kif5Blof does not activate ER stress response genes, but instead disrupts lysosomal function, matrix secretion, and causes deregulated autophagic markers and eventual chondrocyte apoptosis. Ultrastructural and transplantation analysis reveal neighboring cells engulfing extruded kif5Blof chondrocytes. Initial cartilage specification is intact; however, during remodeling, kif5Blof chondrocytes die and the cartilage matrix devoid of hypertrophic chondrocytes remains and impedes normal ossification. Chimeric and mosaic analyses indicate that Kif5B functions cell-autonomously in secretion, nuclear position, cell elongation and maintenance of hypertrophic chondrocytes. Interestingly, large groups of wild-type cells can support elongation of neighboring mutant cells. Finally, mosaic expression of kif5Ba, but not kif5Aa in cartilage rescues the chondrocyte phenotype, further supporting a specific requirement for Kif5B. Cumulatively, we show essential Kif5B functions in promoting cartilage remodeling and chondrocyte maintenance during zebrafish craniofacial morphogenesis.
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Affiliation(s)
- Adrian Santos-Ledo
- Department of Developmental and Molecular Biology. Albert Einstein College of Medicine, Bronx, New York, United States of America
- Institute of Genetic Medicine. Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Marina Garcia-Macia
- Institute for Cellular and Molecular Biosciences. Newcastle University, Newcastle Upon Tyne, United Kingdom
- Institute of Cellular Medicine. Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Philip D Campbell
- Department of Developmental and Molecular Biology. Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Marta Gronska
- Department of Neuroscience. Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Florence L Marlow
- Department of Developmental and Molecular Biology. Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Neuroscience. Albert Einstein College of Medicine, Bronx, New York, United States of America
- Cell Developmental and Regenerative Biology Department. Icahn School of Medicine at Mount Sinai. New York, New York, United States of America
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20
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Ahi EP. Signalling pathways in trophic skeletal development and morphogenesis: Insights from studies on teleost fish. Dev Biol 2016; 420:11-31. [PMID: 27713057 DOI: 10.1016/j.ydbio.2016.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 10/02/2016] [Accepted: 10/03/2016] [Indexed: 12/12/2022]
Abstract
During the development of the vertebrate feeding apparatus, a variety of complicated cellular and molecular processes participate in the formation and integration of individual skeletal elements. The molecular mechanisms regulating the formation of skeletal primordia and their development into specific morphological structures are tightly controlled by a set of interconnected signalling pathways. Some of these pathways, such as Bmp, Hedgehog, Notch and Wnt, are long known for their pivotal roles in craniofacial skeletogenesis. Studies addressing the functional details of their components and downstream targets, the mechanisms of their interactions with other signals as well as their potential roles in adaptive morphological divergence, are currently attracting considerable attention. An increasing number of signalling pathways that had previously been described in different biological contexts have been shown to be important in the regulation of jaw skeletal development and morphogenesis. In this review, I provide an overview of signalling pathways involved in trophic skeletogenesis emphasizing studies of the most species-rich group of vertebrates, the teleost fish, which through their evolutionary history have undergone repeated episodes of spectacular trophic diversification.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Zoology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria; Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland.
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21
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Flanagan-Steet H, Matheny C, Petrey A, Parker J, Steet R. Enzyme-specific differences in mannose phosphorylation between GlcNAc-1-phosphotransferase αβ and γ subunit deficient zebrafish support cathepsin proteases as early mediators of mucolipidosis pathology. Biochim Biophys Acta Gen Subj 2016; 1860:1845-53. [PMID: 27241848 DOI: 10.1016/j.bbagen.2016.05.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 04/28/2016] [Accepted: 05/20/2016] [Indexed: 11/25/2022]
Abstract
Targeting soluble acid hydrolases to lysosomes requires the addition of mannose 6-phosphate residues on their N-glycans. This process is initiated by GlcNAc-1-phosphotransferase, a multi-subunit enzyme encoded by the GNPTAB and GNPTG genes. The GNPTAB gene products (the α and ß subunits) are responsible for recognition and catalysis of hydrolases whereas the GNPTG gene product (the γ subunit) enhances mannose phosphorylation of a subset of hydrolases. Here we identify and characterize a zebrafish gnptg insertional mutant and show that loss of the gamma subunit reduces mannose phosphorylation on a subset glycosidases but does not affect modification of several cathepsin proteases. We further show that glycosidases, but not cathepsins, are hypersecreted from gnptg(-/-) embryonic cells, as evidenced by reduced intracellular activity and increased circulating serum activity. The gnptg(-/-) embryos lack the gross morphological or craniofacial phenotypes shown in gnptab-deficient morphant embryos to result from altered cathepsin activity. Despite the lack of overt phenotypes, decreased fertilization and embryo survival were noted in mutants, suggesting that gnptg associated deposition of mannose 6-phosphate modified hydrolases into oocytes is important for early embryonic development. Collectively, these findings demonstrate that loss of the zebrafish GlcNAc-1-phosphotransferase γ subunit causes enzyme-specific effects on mannose phosphorylation. The finding that cathepsins are normally modified in gnptg(-/-) embryos is consistent with data from gnptab-deficient zebrafish suggesting these proteases are the key mediators of acute pathogenesis. This work also establishes a valuable new model that can be used to probe the functional relevance of GNPTG mutations in the context of a whole animal.
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Affiliation(s)
- Heather Flanagan-Steet
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Courtney Matheny
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Aaron Petrey
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Joshua Parker
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States
| | - Richard Steet
- Complex Carbohydrate Research Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, United States.
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22
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Ko AR, Jin DK, Cho SY, Park SW, Przybylska M, Yew NS, Cheng SH, Kim JS, Kwak MJ, Kim SJ, Sohn YB. AAV8-mediated expression of N-acetylglucosamine-1-phosphate transferase attenuates bone loss in a mouse model of mucolipidosis II. Mol Genet Metab 2016; 117:447-55. [PMID: 26857995 DOI: 10.1016/j.ymgme.2016.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 02/02/2016] [Accepted: 02/02/2016] [Indexed: 11/22/2022]
Abstract
Mucolipidoses II and III (ML II and ML III) are lysosomal disorders in which the mannose 6-phosphate recognition marker is absent from lysosomal hydrolases and other glycoproteins due to mutations in GNPTAB, which encodes two of three subunits of the heterohexameric enzyme, N-acetylglucosamine-1-phosphotransferase. Both disorders are caused by the same gene, but ML II represents the more severe phenotype. Bone manifestations of ML II include hip dysplasia, scoliosis, rickets and osteogenesis imperfecta. In this study, we sought to determine whether a recombinant adeno-associated viral vector (AAV2/8-GNPTAB) could confer high and prolonged gene expression of GNPTAB and thereby influence the pathology in the cartilage and bone tissue of a GNPTAB knock out (KO) mouse model. The results demonstrated significant increases in bone mineral density and content in AAV2/8-GNPTAB-treated as compared to non-treated KO mice. We also showed that IL-6 (interleukin-6) expression in articular cartilage was reduced in AAV2/8-GNPTAB treated ML II mice. Together, these data suggest that AAV-mediated expression of GNPTAB in ML II mice can attenuate bone loss via inhibition of IL-6 production. This study emphasizes the value of the MLII KO mouse to recapitulate the clinical manifestations of the disease and highlights its amenability to therapy.
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Affiliation(s)
- Ah-Ra Ko
- Clinical Research Center, Samsung Biomedical Research Center, Seoul, Republic of Korea; Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dong-Kyu Jin
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
| | - Sung Yoon Cho
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Won Park
- Department of Pediatrics, Cheil General Hospital and Woman's Health Care Center, Dankook University College of Medicine, Seoul, Republic of Korea
| | | | | | | | - Jung-Sun Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Min Jung Kwak
- Department of Pediatrics, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Republic of Korea
| | - Su Jin Kim
- Department of Pediatrics, Myongji Hospital, Seonam University College of Medicine, Goyang, Republic of Korea
| | - Young Bae Sohn
- Department of Medical Genetics, Ajou University Hospital, Ajou University School of Medicine, Suwon, Republic of Korea
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23
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Pashay Ahi E, Walker BS, Lassiter CS, Jónsson ZO. Investigation of the effects of estrogen on skeletal gene expression during zebrafish larval head development. PeerJ 2016; 4:e1878. [PMID: 27069811 PMCID: PMC4824909 DOI: 10.7717/peerj.1878] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/11/2016] [Indexed: 11/20/2022] Open
Abstract
The development of craniofacial skeletal structures requires well-orchestrated tissue interactions controlled by distinct molecular signals. Disruptions in normal function of these molecular signals have been associated with a wide range of craniofacial malformations. A pathway mediated by estrogens is one of those molecular signals that plays role in formation of bone and cartilage including craniofacial skeletogenesis. Studies in zebrafish have shown that while higher concentrations of 17-β estradiol (E 2) cause severe craniofacial defects, treatment with lower concentrations result in subtle changes in head morphology characterized with shorter snouts and flatter faces. The molecular basis for these morphological changes, particularly the subtle skeletal effects mediated by lower E 2 concentrations, remains unexplored. In the present study we address these effects at a molecular level by quantitative expression analysis of sets of candidate genes in developing heads of zebrafish larvae treated with two different E 2 concentrations. To this end, we first validated three suitable reference genes, ppia2, rpl8 and tbp, to permit sensitive quantitative real-time PCR analysis. Next, we profiled the expression of 28 skeletogenesis-associated genes that potentially respond to estrogen signals and play role in craniofacial development. We found E 2 mediated differential expression of genes involved in extracellular matrix (ECM) remodelling, mmp2/9/13, sparc and timp2a, as well as components of skeletogenic pathways, bmp2a, erf, ptch1/2, rankl, rarab and sfrp1a. Furthermore, we identified a co-expressed network of genes, including cpn1, dnajc3, esr1, lman1, rrbp1a, ssr1 and tram1 with a stronger inductive response to a lower dose of E 2 during larval head development.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Life and Environmental Sciences, University of Iceland , Reykjavik , Iceland
| | | | | | - Zophonías O Jónsson
- Institute of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland; Biomedical Center, University of Iceland, Reykjavik, Iceland
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24
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Flanagan-Steet H, Aarnio M, Kwan B, Guihard P, Petrey A, Haskins M, Blanchard F, Steet R. Cathepsin-Mediated Alterations in TGFß-Related Signaling Underlie Disrupted Cartilage and Bone Maturation Associated With Impaired Lysosomal Targeting. J Bone Miner Res 2016; 31:535-48. [PMID: 26404503 PMCID: PMC4808492 DOI: 10.1002/jbmr.2722] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 09/21/2015] [Accepted: 09/23/2015] [Indexed: 11/11/2022]
Abstract
Hypersecretion of acid hydrolases is a hallmark feature of mucolipidosis II (MLII), a lysosomal storage disease caused by loss of carbohydrate-dependent lysosomal targeting. Inappropriate extracellular action of these hydrolases is proposed to contribute to skeletal pathogenesis, but the mechanisms that connect hydrolase activity to the onset of disease phenotypes remain poorly understood. Here we link extracellular cathepsin K activity to abnormal bone and cartilage development in MLII animals by demonstrating that it disrupts the balance of TGFß-related signaling during chondrogenesis. TGFß-like Smad2,3 signals are elevated and BMP-like Smad1,5,8 signals reduced in both feline and zebrafish MLII chondrocytes and osteoblasts, maintaining these cells in an immature state. Reducing either cathepsin K activity or expression of the transcriptional regulator Sox9a in MLII zebrafish significantly improved phenotypes. We further identify components of the large latent TGFß complex as novel targets of cathepsin K at neutral pH, providing a possible mechanism for enhanced Smad2,3 activation in vivo. These findings highlight the complexity of the skeletal disease associated with MLII and bring new insight to the role of secreted cathepsin proteases in cartilage development and growth factor regulation.
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Affiliation(s)
| | - Megan Aarnio
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Brian Kwan
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | | | - Aaron Petrey
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Mark Haskins
- Departments of Pathology and Clinical Studies, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | | | - Richard Steet
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
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25
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Lemmens K, Bollaerts I, Bhumika S, de Groef L, Van Houcke J, Darras VM, Van Hove I, Moons L. Matrix metalloproteinases as promising regulators of axonal regrowth in the injured adult zebrafish retinotectal system. J Comp Neurol 2015; 524:1472-93. [PMID: 26509469 DOI: 10.1002/cne.23920] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 10/16/2015] [Accepted: 10/26/2015] [Indexed: 02/01/2023]
Abstract
Overcoming the failure of axon regeneration in the mammalian central nervous system (CNS) after injury remains a major challenge, which makes the search for proregenerative molecules essential. Matrix metalloproteinases (MMPs) have been implicated in axonal outgrowth during CNS development and show increased expression levels during vertebrate CNS repair. In mammals, MMPs are believed to alter the suppressive extracellular matrix to become more permissive for axon regrowth. We investigated the role of MMPs in axonal regeneration following optic nerve crush (ONC) in adult zebrafish, which fully recover from such injuries due to a high intrinsic axon growth capacity and a less inhibitory environment. Lowering general retinal MMP activity through intravitreal injections of GM6001 after ONC strongly reduced retinal ganglion cell (RGC) axonal regrowth, without influencing RGC survival. Based on a recently performed transcriptome profiling study, the expression pattern of four MMPs after ONC was determined via combined use of western blotting and immunostainings. Mmp-2 and -13a were increasingly present in RGC somata during axonal regrowth. Moreover, Mmp-2 and -9 became upregulated in regrowing RGC axons and inner plexiform layer (IPL) synapses, respectively. In contrast, after an initial rise in IPL neurites and RGC axons during the injury response, Mmp-14 expression decreased during regeneration. Altogether, a phase-dependent expression pattern for each specific MMP was observed, implicating them in axonal regrowth and inner retina remodeling after injury. In conclusion, these data suggest a novel, neuron-intrinsic function for multiple MMPs in axon regrowth that is distinct from breaking down environmental barriers. J. Comp. Neurol. 524:1472-1493, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Kim Lemmens
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
| | - Ilse Bollaerts
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
| | - Stitipragyan Bhumika
- Laboratory of Comparative Endocrinology, Biology Department, KU Leuven, Leuven, Belgium
| | - Lies de Groef
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
| | - Jessie Van Houcke
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
| | - Veerle M Darras
- Laboratory of Comparative Endocrinology, Biology Department, KU Leuven, Leuven, Belgium
| | - Inge Van Hove
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
| | - Lieve Moons
- Laboratory of Neural Circuit Development and Regeneration, Biology Department, KU Leuven, Leuven, Belgium
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26
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Qian Y, van Meel E, Flanagan-Steet H, Yox A, Steet R, Kornfeld S. Analysis of mucolipidosis II/III GNPTAB missense mutations identifies domains of UDP-GlcNAc:lysosomal enzyme GlcNAc-1-phosphotransferase involved in catalytic function and lysosomal enzyme recognition. J Biol Chem 2014; 290:3045-56. [PMID: 25505245 DOI: 10.1074/jbc.m114.612507] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
UDP-GlcNAc:lysosomal enzyme GlcNAc-1-phosphotransferase tags newly synthesized lysosomal enzymes with mannose 6-phosphate recognition markers, which are required for their targeting to the endolysosomal system. GNPTAB encodes the α and β subunits of GlcNAc-1-phosphotransferase, and mutations in this gene cause the lysosomal storage disorders mucolipidosis II and III αβ. Prior investigation of missense mutations in GNPTAB uncovered amino acids in the N-terminal region and within the DMAP domain involved in Golgi retention of GlcNAc-1-phosphotransferase and its ability to specifically recognize lysosomal hydrolases, respectively. Here, we undertook a comprehensive analysis of the remaining missense mutations in GNPTAB reported in mucolipidosis II and III αβ patients using cell- and zebrafish-based approaches. We show that the Stealth domain harbors the catalytic site, as some mutations in these regions greatly impaired the activity of the enzyme without affecting its Golgi localization and proteolytic processing. We also demonstrate a role for the Notch repeat 1 in lysosomal hydrolase recognition, as missense mutations in conserved cysteine residues in this domain do not affect the catalytic activity but impair mannose phosphorylation of certain lysosomal hydrolases. Rescue experiments using mRNA bearing Notch repeat 1 mutations in GNPTAB-deficient zebrafish revealed selective effects on hydrolase recognition that differ from the DMAP mutation. Finally, the mutant R587P, located in the spacer between Notch 2 and DMAP, was partially rescued by overexpression of the γ subunit, suggesting a role for this region in γ subunit binding. These studies provide new insight into the functions of the different domains of the α and β subunits.
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Affiliation(s)
- Yi Qian
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | - Eline van Meel
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
| | | | - Alex Yox
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Richard Steet
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602
| | - Stuart Kornfeld
- From the Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 and
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27
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Ahi EP, Kapralova KH, Pálsson A, Maier VH, Gudbrandsson J, Snorrason SS, Jónsson ZO, Franzdóttir SR. Transcriptional dynamics of a conserved gene expression network associated with craniofacial divergence in Arctic charr. EvoDevo 2014; 5:40. [PMID: 25419450 PMCID: PMC4240837 DOI: 10.1186/2041-9139-5-40] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 09/17/2014] [Indexed: 12/30/2022] Open
Abstract
Background Understanding the molecular basis of craniofacial variation can provide insights into key developmental mechanisms of adaptive changes and their role in trophic divergence and speciation. Arctic charr (Salvelinus alpinus) is a polymorphic fish species, and, in Lake Thingvallavatn in Iceland, four sympatric morphs have evolved distinct craniofacial structures. We conducted a gene expression study on candidates from a conserved gene coexpression network, focusing on the development of craniofacial elements in embryos of two contrasting Arctic charr morphotypes (benthic and limnetic). Results Four Arctic charr morphs were studied: one limnetic and two benthic morphs from Lake Thingvallavatn and a limnetic reference aquaculture morph. The presence of morphological differences at developmental stages before the onset of feeding was verified by morphometric analysis. Following up on our previous findings that Mmp2 and Sparc were differentially expressed between morphotypes, we identified a network of genes with conserved coexpression across diverse vertebrate species. A comparative expression study of candidates from this network in developing heads of the four Arctic charr morphs verified the coexpression relationship of these genes and revealed distinct transcriptional dynamics strongly correlated with contrasting craniofacial morphologies (benthic versus limnetic). A literature review and Gene Ontology analysis indicated that a significant proportion of the network genes play a role in extracellular matrix organization and skeletogenesis, and motif enrichment analysis of conserved noncoding regions of network candidates predicted a handful of transcription factors, including Ap1 and Ets2, as potential regulators of the gene network. The expression of Ets2 itself was also found to associate with network gene expression. Genes linked to glucocorticoid signalling were also studied, as both Mmp2 and Sparc are responsive to this pathway. Among those, several transcriptional targets and upstream regulators showed differential expression between the contrasting morphotypes. Interestingly, although selected network genes showed overlapping expression patterns in situ and no morph differences, Timp2 expression patterns differed between morphs. Conclusion Our comparative study of transcriptional dynamics in divergent craniofacial morphologies of Arctic charr revealed a conserved network of coexpressed genes sharing functional roles in structural morphogenesis. We also implicate transcriptional regulators of the network as targets for future functional studies. Electronic supplementary material The online version of this article (doi:10.1186/2041-9139-5-40) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
| | - Kalina Hristova Kapralova
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
| | - Arnar Pálsson
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland ; Biomedical Center, University of Iceland, Vatnsmýrarvegur 16, 101 Reykjavik, Iceland
| | - Valerie Helene Maier
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
| | - Jóhannes Gudbrandsson
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
| | - Sigurdur S Snorrason
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
| | - Zophonías O Jónsson
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland ; Biomedical Center, University of Iceland, Vatnsmýrarvegur 16, 101 Reykjavik, Iceland
| | - Sigrídur Rut Franzdóttir
- Institute of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland
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28
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Paton L, Bitoun E, Kenyon J, Priestman DA, Oliver PL, Edwards B, Platt FM, Davies KE. A novel mouse model of a patient mucolipidosis II mutation recapitulates disease pathology. J Biol Chem 2014; 289:26709-26721. [PMID: 25107912 PMCID: PMC4175314 DOI: 10.1074/jbc.m114.586156] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mucolipidosis II (MLII) is a lysosomal storage disorder caused by loss of N-acetylglucosamine-1-phosphotransferase, which tags lysosomal enzymes with a mannose 6-phosphate marker for transport to the lysosome. In MLII, the loss of this marker leads to deficiency of multiple enzymes and non-enzymatic proteins in the lysosome, leading to the storage of multiple substrates. Here we present a novel mouse model of MLII homozygous for a patient mutation in the GNPTAB gene. Whereas the current gene knock-out mouse model of MLII lacks some of the characteristic features of the human disease, our novel mouse model more fully recapitulates the human pathology, showing growth retardation, skeletal and facial abnormalities, increased circulating lysosomal enzymatic activities, intracellular lysosomal storage, and reduced life span. Importantly, MLII behavioral deficits are characterized for the first time, including impaired motor function and psychomotor retardation. Histological analysis of the brain revealed progressive neurodegeneration in the cerebellum with severe Purkinje cell loss as the underlying cause of the ataxic gait. In addition, based on the loss of Npc2 (Niemann-Pick type C 2) protein expression in the brain, the mice were treated with 2-hydroxypropyl-β-cyclodextrin, a drug previously reported to rescue Purkinje cell death in a mouse model of Niemann-Pick type C disease. No improvement in brain pathology was observed. This indicates that cerebellar degeneration is not primarily triggered by loss of Npc2 function. This study emphasizes the value of modeling MLII patient mutations to generate clinically relevant mouse mutants to elucidate the pathogenic molecular pathways of MLII and address their amenability to therapy.
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Affiliation(s)
- Leigh Paton
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and
| | - Emmanuelle Bitoun
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and
| | - Janet Kenyon
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and
| | - David A Priestman
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Peter L Oliver
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and
| | - Benjamin Edwards
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and
| | - Frances M Platt
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Kay E Davies
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, South Parks Road, Oxford OX1 3PT, United Kingdom and.
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29
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The DMAP interaction domain of UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase is a substrate recognition module. Proc Natl Acad Sci U S A 2013; 110:10246-51. [PMID: 23733939 DOI: 10.1073/pnas.1308453110] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-1-phosphotransferase) is an α2β2γ2 heterohexamer that mediates the initial step in the formation of the mannose 6-phosphate recognition signal on lysosomal acid hydrolases. We previously reported that the specificity of the reaction is determined by the ability of the α/β subunits to recognize a conformation-dependent protein determinant present on the acid hydrolases. We now present evidence that the DNA methyltransferase-associated protein (DMAP) interaction domain of the α subunit functions in this recognition process. First, GST-DMAP pulled down several acid hydrolases, but not nonlysosomal glycoproteins. Second, recombinant GlcNAc-1-phosphotransferase containing a missense mutation in the DMAP interaction domain (Lys732Asn) identified in a patient with mucolipidosis II exhibited full activity toward the simple sugar α-methyl d-mannoside but impaired phosphorylation of acid hydrolases. Finally, unlike the WT enzyme, expression of the K732N mutant in a zebrafish model of mucolipidosis II failed to correct the phenotypic abnormalities. These results indicate that the DMAP interaction domain of the α subunit functions in the selective recognition of acid hydrolase substrates and provides an explanation for the impaired phosphorylation of acid hydrolases in a patient with mucolipidosis II.
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30
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Extracellular Matrix Remodeling in Zebrafish Development. EXTRACELLULAR MATRIX IN DEVELOPMENT 2013. [DOI: 10.1007/978-3-642-35935-4_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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31
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Kollmann K, Damme M, Markmann S, Morelle W, Schweizer M, Hermans-Borgmeyer I, Röchert AK, Pohl S, Lübke T, Michalski JC, Käkelä R, Walkley SU, Braulke T. Lysosomal dysfunction causes neurodegeneration in mucolipidosis II 'knock-in' mice. ACTA ACUST UNITED AC 2012; 135:2661-75. [PMID: 22961545 DOI: 10.1093/brain/aws209] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Mucolipidosis II is a neurometabolic lysosomal trafficking disorder of infancy caused by loss of mannose 6-phosphate targeting signals on lysosomal proteins, leading to lysosomal dysfunction and accumulation of non-degraded material. However, the identity of storage material and mechanisms of neurodegeneration in mucolipidosis II are unknown. We have generated 'knock-in' mice with a common mucolipidosis II patient mutation that show growth retardation, progressive brain atrophy, skeletal abnormalities, elevated lysosomal enzyme activities in serum, lysosomal storage in fibroblasts and brain and premature death, closely mimicking the mucolipidosis II disease in humans. The examination of affected mouse brains at different ages by immunohistochemistry, ultrastructural analysis, immunoblotting and mass spectrometric analyses of glycans and anionic lipids revealed that the expression and proteolytic processing of distinct lysosomal proteins such as α-l-fucosidase, β-hexosaminidase, α-mannosidase or Niemann-Pick C2 protein are more significantly impacted by the loss of mannose 6-phosphate residues than enzymes reaching lysosomes independently of this targeting mechanism. As a consequence, fucosylated N-glycans, GM2 and GM3 gangliosides, cholesterol and bis(monoacylglycero)phosphate accumulate progressively in the brain of mucolipidosis II mice. Prominent astrogliosis and the accumulation of organelles and storage material in focally swollen axons were observed in the cerebellum and were accompanied by a loss of Purkinje cells. Moreover, an increased neuronal level of the microtubule-associated protein 1 light chain 3 and the formation of p62-positive neuronal aggregates indicate an impairment of constitutive autophagy in the mucolipidosis II brain. Our findings demonstrate the essential role of mannose 6-phosphate for selected lysosomal proteins to maintain the capability for degradation of sequestered components in lysosomes and autophagolysosomes and prevent neurodegeneration. These lysosomal proteins might be a potential target for a valid therapeutic approach for mucolipidosis II disease.
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Affiliation(s)
- K Kollmann
- Department of Biochemistry, Children’s Hospital, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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Mabee BP, Balhoff JP, Dahdul WM, Lapp H, Midford PE, Vision TJ, Westerfield M. 500,000 fish phenotypes: The new informatics landscape for evolutionary and developmental biology of the vertebrate skeleton. ZEITSCHRIFT FUR ANGEWANDTE ICHTHYOLOGIE = JOURNAL OF APPLIED ICHTHYOLOGY 2012; 28:300-305. [PMID: 22736877 PMCID: PMC3377363 DOI: 10.1111/j.1439-0426.2012.01985.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 03/08/2012] [Indexed: 05/02/2023]
Abstract
The rich phenotypic diversity that characterizes the vertebrate skeleton results from evolutionary changes in regulation of genes that drive development. Although relatively little is known about the genes that underlie the skeletal variation among fish species, significant knowledge of genetics and development is available for zebrafish. Because developmental processes are highly conserved, this knowledge can be leveraged for understanding the evolution of skeletal diversity. We developed the Phenoscape Knowledgebase (KB; http://kb.phenoscape.org) to yield testable hypotheses of candidate genes involved in skeletal evolution. We developed a community anatomy ontology for fishes and ontology-based methods to represent complex free-text character descriptions of species in a computable format. With these tools, we populated the KB with comparative morphological data from the literature on over 2,500 teleost fishes (mainly Ostariophysi) resulting in over 500,000 taxon phenotype annotations. The KB integrates these data with similarly structured phenotype data from zebrafish genes (http://zfin.org). Using ontology-based reasoning, candidate genes can be inferred for the phenotypes that vary across taxa, thereby uniting genetic and phenotypic data to formulate evo-devo hypotheses. The morphological data in the KB can be browsed, sorted, and aggregated in ways that provide unprecedented possibilities for data mining and discovery.
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Affiliation(s)
- By Paula Mabee
- Department of Biology, 414 East Clark Street, University of South Dakota, Vermillion, South Dakota, United States of America
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Flanagan-Steet HR, Steet R. "Casting" light on the role of glycosylation during embryonic development: insights from zebrafish. Glycoconj J 2012; 30:33-40. [PMID: 22638861 DOI: 10.1007/s10719-012-9390-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 04/23/2012] [Accepted: 04/25/2012] [Indexed: 12/23/2022]
Abstract
Zebrafish (Danio rerio) remains a versatile model organism for the investigation of early development and organogenesis, and has emerged as a valuable platform for drug discovery and toxicity evaluation [1-6]. Harnessing the genetic power and experimental accessibility of this system, three decades of research have identified key genes and pathways that control the development of multiple organ systems and tissues, including the heart, kidney, and craniofacial cartilage, as well as the hematopoietic, vascular, and central and peripheral nervous systems [7-31]. In addition to their application in large mutagenic screens, zebrafish has been used to model a variety of diseases such as diabetes, polycystic kidney disease, muscular dystrophy and cancer [32-36]. As this work continues to intersect with cellular pathways and processes such as lipid metabolism, glycosylation and vesicle trafficking, investigators are often faced with the challenge of determining the degree to which these pathways are functionally conserved in zebrafish. While they share a high degree of genetic homology with mouse and human, the manner in which cellular pathways are regulated in zebrafish during early development, and the differences in the organ physiology, warrant consideration before functional studies can be effectively interpreted and compared with other vertebrate systems. This point is particularly relevant for glycosylation since an understanding of the glycan diversity and the mechanisms that control glycan biosynthesis during zebrafish embryogenesis (as in many organisms) is still developing.Nonetheless, a growing number of studies in zebrafish have begun to cast light on the functional roles of specific classes of glycans during organ and tissue development. While many of the initial efforts involved characterizing identified mutants in a number of glycosylation pathways, the use of reverse genetic approaches to directly model glycosylation-related disorders is now increasingly popular. In this review, the glycomics of zebrafish and the developmental expression of their glycans will be briefly summarized along with recent chemical biology approaches to visualize certain classes of glycans within developing embryos. Work regarding the role of protein-bound glycans and glycosaminoglycans (GAG) in zebrafish development and organogenesis will also be highlighted. Lastly, future opportunities and challenges in the expanding field of zebrafish glycobiology are discussed.
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