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Xu M, Li J, Xia L, Du Y, Wu B, Shi X, Tian N, Pang Y, Yi L, Chen M, Song W, Dong Z. PCSK6 exacerbates Alzheimer's disease pathogenesis by promoting MT5-MMP maturation. Exp Neurol 2024; 374:114688. [PMID: 38216110 DOI: 10.1016/j.expneurol.2024.114688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/18/2023] [Accepted: 01/06/2024] [Indexed: 01/14/2024]
Abstract
Proprotein convertase subtilisin/kexin type 6 (PCSK6) is a calcium-dependent serine proteinase that regulates the proteolytic activity of various precursor proteins and facilitates protein maturation. Dysregulation of PCSK6 expression or function has been implicated in several pathological processes including nervous system diseases. However, whether and how PCSK6 is involved in the pathogenesis of Alzheimer's disease (AD) remains unclear. In this study, we reported that the expression of PCSK6 was significantly increased in the brain tissues of postmortem AD patients and APP23/PS45 transgenic AD model mice, as well as N2AAPP cells. Genetic knockdown of PCSK6 reduced amyloidogenic processing of APP in N2AAPP cells by suppressing the activation of membrane-type 5-matrix metalloproteinase (MT5-MMP), referred to as η-secretase. We further found that PCSK6 cleaved and activated MT5-MMP by recognizing the RRRNKR sequence in its N-terminal propeptide domain in N2A cells. The mutation or knockout of this cleavage motif prevented PCSK6 from interacting with MT5-MMP and performing cleavage. Importantly, genetic knockdown of PCSK6 with adeno-associated virus (AAV) reduced Aβ production and ameliorated hippocampal long-term potentiation (LTP) and long-term spatial learning and memory in APP23/PS45 transgenic mice. Taken together, these results demonstrate that genetic knockdown of PCSK6 effectively alleviate AD-related pathology and cognitive impairments by inactivating MT5-MMP, highlighting its potential as a novel therapeutic target for AD treatment.
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Affiliation(s)
- Mingliang Xu
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China; Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China
| | - Junjie Li
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Lei Xia
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Yehong Du
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Bin Wu
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Xiuyu Shi
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Na Tian
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Yayan Pang
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Lilin Yi
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Mulan Chen
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Weihong Song
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China; Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, Zhejiang Clinical Research Center for Mental Disorders, School of Mental Health and The Affiliated Kangning Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Zhifang Dong
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China.
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Marafie SK, Al-Mulla F. An Overview of the Role of Furin in Type 2 Diabetes. Cells 2023; 12:2407. [PMID: 37830621 PMCID: PMC10571965 DOI: 10.3390/cells12192407] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
Post-translational modifications (PTMs) play important roles in regulating several human diseases, like cancer, neurodegenerative disorders, and metabolic disorders. Investigating PTMs' contribution to protein functions is critical for modern biology and medicine. Proprotein convertases (PCs) are irreversible post-translational modifiers that have been extensively studied and are considered as key targets for novel therapeutics. They cleave proteins at specific sites causing conformational changes affecting their functions. Furin is considered as a PC model in regulating growth factors and is involved in regulating many pro-proteins. The mammalian target of the rapamycin (mTOR) signaling pathway is another key player in regulating cellular processes and its dysregulation is linked to several diseases including type 2 diabetes (T2D). The role of furin in the context of diabetes has been rarely explored and is currently lacking. Moreover, furin variants have altered activity that could have implications on overall health. In this review, we aim to highlight the role of furin in T2D in relation to mTOR signaling. We will also address furin genetic variants and their potential effect on T2D and β-cell functions. Understanding the role of furin in prediabetes and dissecting it from other confounding factors like obesity is crucial for future therapeutic interventions in metabolic disorders.
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Affiliation(s)
- Sulaiman K. Marafie
- Biochemistry and Molecular Biology Department, Dasman Diabetes Institute, P.O. Box 1180, Dasman 15462, Kuwait
| | - Fahd Al-Mulla
- Genetics and Bioinformatics Department, Dasman Diabetes Institute, P.O. Box 1180, Dasman 15462, Kuwait
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3
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Proprotein Convertase Subtilisin/Kexin 6 in Cardiovascular Biology and Disease. Int J Mol Sci 2022; 23:ijms232113429. [DOI: 10.3390/ijms232113429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/01/2022] [Accepted: 11/02/2022] [Indexed: 11/06/2022] Open
Abstract
Proprotein convertase subtilisin/kexin 6 (PCSK6) is a secreted serine protease expressed in most major organs, where it cleaves a wide range of growth factors, signaling molecules, peptide hormones, proteolytic enzymes, and adhesion proteins. Studies in Pcsk6-deficient mice have demonstrated the importance of Pcsk6 in embryonic development, body axis specification, ovarian function, and extracellular matrix remodeling in articular cartilage. In the cardiovascular system, PCSK6 acts as a key modulator in heart formation, lipoprotein metabolism, body fluid homeostasis, cardiac repair, and vascular remodeling. To date, dysregulated PCSK6 expression or function has been implicated in major cardiovascular diseases, including atrial septal defects, hypertension, atherosclerosis, myocardial infarction, and cardiac aging. In this review, we describe biochemical characteristics and posttranslational modifications of PCSK6. Moreover, we discuss the role of PCSK6 and related molecular mechanisms in cardiovascular biology and disease.
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4
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Dobó J, Kocsis A, Dani R, Gál P. Proprotein Convertases and the Complement System. Front Immunol 2022; 13:958121. [PMID: 35874789 PMCID: PMC9296861 DOI: 10.3389/fimmu.2022.958121] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/13/2022] [Indexed: 11/27/2022] Open
Abstract
Proteins destined for secretion - after removal of the signal sequence - often undergo further proteolytic processing by proprotein convertases (PCs). Prohormones are typically processed in the regulated secretory pathway, while most plasma proteins travel though the constitutive pathway. The complement system is a major proteolytic cascade in the blood, serving as a first line of defense against microbes and also contributing to the immune homeostasis. Several complement components, namely C3, C4, C5 and factor I (FI), are multi-chain proteins that are apparently processed by PCs intracellularly. Cleavage occurs at consecutive basic residues and probably also involves the action of carboxypeptidases. The most likely candidate for the intracellular processing of complement proteins is furin, however, because of the overlapping specificities of basic amino acid residue-specific proprotein convertases, other PCs might be involved. To our surprise, we have recently discovered that processing of another complement protein, mannan-binding lectin-associated serine protease-3 (MASP-3) occurs in the blood by PCSK6 (PACE4). A similar mechanism had been described for the membrane protease corin, which is also activated extracellularly by PCSK6. In this review we intend to point out that the proper functioning of the complement system intimately depends on the action of proprotein convertases. In addition to the non-enzymatic components (C3, C4, C5), two constitutively active complement proteases are directly activated by PCs either intracellularly (FI), or extracellularly (MASP-3), moreover indirectly, through the constitutive activation of pro-factor D by MASP-3, the activity of the alternative pathway also depends on a PC present in the blood.
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Affiliation(s)
| | | | | | - Péter Gál
- *Correspondence: József Dobó, ; Péter Gál,
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Bellomo TR, Bone WP, Chen BY, Gawronski KAB, Zhang D, Park J, Levin M, Tsao N, Klarin D, Lynch J, Assimes TL, Gaziano JM, Wilson PW, Cho K, Vujkovic M, O’Donnell CJ, Chang KM, Tsao PS, Rader DJ, Ritchie MD, Damrauer SM, Voight BF. Multi-Trait Genome-Wide Association Study of Atherosclerosis Detects Novel Pleiotropic Loci. Front Genet 2022; 12:787545. [PMID: 35186008 PMCID: PMC8847690 DOI: 10.3389/fgene.2021.787545] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/22/2021] [Indexed: 11/13/2022] Open
Abstract
Although affecting different arterial territories, the related atherosclerotic vascular diseases coronary artery disease (CAD) and peripheral artery disease (PAD) share similar risk factors and have shared pathobiology. To identify novel pleiotropic loci associated with atherosclerosis, we performed a joint analysis of their shared genetic architecture, along with that of common risk factors. Using summary statistics from genome-wide association studies of nine known atherosclerotic (CAD, PAD) and atherosclerosis risk factors (body mass index, smoking initiation, type 2 diabetes, low density lipoprotein, high density lipoprotein, total cholesterol, and triglycerides), we perform 15 separate multi-trait genetic association scans which resulted in 25 novel pleiotropic loci not yet reported as genome-wide significant for their respective traits. Colocalization with single-tissue eQTLs identified candidate causal genes at 14 of the detected signals. Notably, the signal between PAD and LDL-C at the PCSK6 locus affects PCSK6 splicing in human liver tissue and induced pluripotent derived hepatocyte-like cells. These results show that joint analysis of related atherosclerotic disease traits and their risk factors allowed identification of unified biology that may offer the opportunity for therapeutic manipulation. The signal at PCSK6 represent possible shared causal biology where existing inhibitors may be able to be leveraged for novel therapies.
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Affiliation(s)
- Tiffany R. Bellomo
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - William P. Bone
- Genomics and Computational Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Brian Y. Chen
- School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, United States
| | | | - David Zhang
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, United States
| | - Joseph Park
- Genomics and Computational Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Michael Levin
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Division of Cardiovascular Medicine, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, United States
| | - Noah Tsao
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, United States
| | - Derek Klarin
- VA Boston Healthcare System, Boston, MA, United States
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, United States
- Division of Vascular Surgery and Endovascular Therapy, University of Florida School of Medicine, Gainesville, FL, United States
- Department of Surgery, Massachusetts General Hospital, Boston, MA, United States
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, United States
| | - Julie Lynch
- VA Informatics and Computing Infrastructure, VA Salt Lake City Health Care System, Salt Lake City, UT, United States
- University of Massachusetts College of Nursing and Health Sciences, Boston, MA, United States
| | - Themistocles L. Assimes
- VA Palo Alto Health Care System, Palo Alto, CA, United States
- Department of Medicine, Stanford University, Stanford, CA, United States
| | - J. Michael Gaziano
- VA Boston Healthcare System, Boston, MA, United States
- Massachusetts Veterans Epidemiology Research and Information Center, Veterans Affairs Boston Healthcare System, Boston, MA, United States
- Department of Medicine, Brigham Women’s Hospital, Boston, MA, United States
| | - Peter W. Wilson
- Atlanta VA Medical Center, Decatur, GA, United States
- Division of Cardiology, Emory University School of Medicine, Atlanta, GA, United States
| | - Kelly Cho
- VA Boston Healthcare System, Boston, MA, United States
- Department of Medicine, Brigham Women’s Hospital, Boston, MA, United States
| | - Marijana Vujkovic
- Division of Cardiovascular Medicine, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Christopher J. O’Donnell
- VA Boston Healthcare System, Boston, MA, United States
- Department of Medicine, Brigham Women’s Hospital, Boston, MA, United States
| | - Kyong-Mi Chang
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, United States
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Philip S. Tsao
- VA Palo Alto Health Care System, Palo Alto, CA, United States
- Department of Medicine, Stanford University, Stanford, CA, United States
| | - Daniel J. Rader
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, United States
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, United States
| | - Marylyn D. Ritchie
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, United States
- Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Precision Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Scott M. Damrauer
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, United States
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Benjamin F. Voight
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, United States
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, United States
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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6
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Vardhan S, Sahoo SK. Virtual screening by targeting proteolytic sites of furin and TMPRSS2 to propose potential compounds obstructing the entry of SARS-CoV-2 virus into human host cells. J Tradit Complement Med 2022; 12:6-15. [PMID: 33868970 PMCID: PMC8040387 DOI: 10.1016/j.jtcme.2021.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND AIM The year 2020 begins with the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that cause the disease COVID-19, and continue till today. As of March 23, 2021, the outbreak has infected 124,313,054 worldwide with a total death of 2,735,707. The use of traditional medicines as an adjuvant therapy with western drugs can lower the fatality rate due to the COVID-19. Therefore, in silico molecular docking study was performed to search potential phytochemicals and drugs that can block the entry of SARS-CoV-2 into host cells by inhibiting the proteolytic cleavage activity of furin and TMPRSS2. EXPERIMENTAL PROCEDURE The protein-protein docking of the host proteases furin and TMPRSS2 was carried out with the virus spike (S) protein to examine the conformational details and residues involved in the complex formation. Subsequently, a library of 163 ligands containing phytochemicals and drugs was virtually screened to propose potential hits that can inhibit the proteolytic cleavage activity of furin and TMPRSS2. RESULTS AND CONCLUSION The phytochemicals like limonin, gedunin, eribulin, pedunculagin, limonin glycoside and betunilic acid bind at the active site of both furin and TMPRSS2. Limonin and gedunin found mainly in the citrus fruits and neem showed the highest binding energy at the active site of furin and TMPRSS2, respectively. The polyphenols found in green tea can also be useful in suppressing the furin activity. Among the drugs, the drug nafamostat may be more beneficial than the camostat in suppressing the activity of TMPRSS2.
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Affiliation(s)
- Seshu Vardhan
- Department of Chemistry, Sardar Vallabhbhai National Institute of Technology (SVNIT), Surat, 395007, Gujarat, India
| | - Suban K. Sahoo
- Department of Chemistry, Sardar Vallabhbhai National Institute of Technology (SVNIT), Surat, 395007, Gujarat, India
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Abstract
The kexin-like proprotein convertases perform the initial proteolytic cleavages that ultimately generate a variety of different mature peptide and proteins, ranging from brain neuropeptides to endocrine peptide hormones, to structural proteins, among others. In this review, we present a general introduction to proprotein convertase structure and biochemistry, followed by a comprehensive discussion of each member of the kexin-like subfamily of proprotein convertases. We summarize current knowledge of human proprotein convertase insufficiency syndromes, including genome-wide analyses of convertase polymorphisms, and compare these to convertase null and mutant mouse models. These mouse models have illuminated our understanding of the roles specific convertases play in human disease and have led to the identification of convertase-specific substrates; for example, the identification of procorin as a specific PACE4 substrate in the heart. We also discuss the limitations of mouse null models in interpreting human disease, such as differential precursor cleavage due to species-specific sequence differences, and the challenges presented by functional redundancy among convertases in attempting to assign specific cleavages and/or physiological roles. However, in most cases, knockout mouse models have added substantively both to our knowledge of diseases caused by human proprotein convertase insufficiency and to our appreciation of their normal physiological roles, as clearly seen in the case of the furin, proprotein convertase 1/3, and proprotein convertase 5/6 mouse models. The creation of more sophisticated mouse models with tissue- or temporally-restricted expression of specific convertases will improve our understanding of human proprotein convertase insufficiency and potentially provide support for the emerging concept of therapeutic inhibition of convertases.
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Affiliation(s)
- Manita Shakya
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Iris Lindberg
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
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Corbière A, Vaudry H, Chan P, Walet-Balieu ML, Lecroq T, Lefebvre A, Pineau C, Vaudry D. Strategies for the Identification of Bioactive Neuropeptides in Vertebrates. Front Neurosci 2019; 13:948. [PMID: 31619945 PMCID: PMC6759750 DOI: 10.3389/fnins.2019.00948] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/22/2019] [Indexed: 11/13/2022] Open
Abstract
Neuropeptides exert essential functions in animal physiology by controlling e.g., reproduction, development, growth, energy homeostasis, cardiovascular activity and stress response. Thus, identification of neuropeptides has been a very active field of research over the last decades. This review article presents the various methods used to discover novel bioactive peptides in vertebrates. Initially identified on the basis of their biological activity, some neuropeptides have also been discovered for their ability to bind/activate a specific receptor or based on their biochemical characteristics such as C-terminal amidation which concerns half of the known neuropeptides. More recently, sequencing of the genome of many representative species has facilitated peptidomic approaches using mass spectrometry and in silico screening of genomic libraries. Through these different approaches, more than a hundred of bioactive neuropeptides have already been identified in vertebrates. Nevertheless, researchers continue to find new neuropeptides or to identify novel functions of neuropeptides that had not been detected previously, as it was recently the case for nociceptin.
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Affiliation(s)
- Auriane Corbière
- Normandie Univ, UNIROUEN, Inserm, Laboratory of Neuronal and Neuroendocrine Communication and Differentiation, Neuropeptides, Neuronal Death and Cell Plasticity Team, Rouen, France
| | - Hubert Vaudry
- Normandie Univ, UNIROUEN, Inserm, Laboratory of Neuronal and Neuroendocrine Communication and Differentiation, Neuropeptides, Neuronal Death and Cell Plasticity Team, Rouen, France.,Normandie Univ, UNIROUEN, Regional Cell Imaging Platform of Normandy (PRIMACEN), Rouen, France
| | - Philippe Chan
- Normandie Univ, UNIROUEN, Rouen Proteomic Platform (PISSARO), Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Marie-Laure Walet-Balieu
- Normandie Univ, UNIROUEN, Rouen Proteomic Platform (PISSARO), Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Thierry Lecroq
- Normandie Univ, UNIROUEN, LITIS EA 4108, Information Processing in Biology & Health, Rouen, France
| | - Arnaud Lefebvre
- Normandie Univ, UNIROUEN, LITIS EA 4108, Information Processing in Biology & Health, Rouen, France
| | | | - David Vaudry
- Normandie Univ, UNIROUEN, Inserm, Laboratory of Neuronal and Neuroendocrine Communication and Differentiation, Neuropeptides, Neuronal Death and Cell Plasticity Team, Rouen, France.,Normandie Univ, UNIROUEN, Regional Cell Imaging Platform of Normandy (PRIMACEN), Rouen, France.,Normandie Univ, UNIROUEN, Rouen Proteomic Platform (PISSARO), Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
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9
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Lu X. Structure and Function of Proprotein Convertase Subtilisin/kexin Type 9 (PCSK9) in Hyperlipidemia and Atherosclerosis. Curr Drug Targets 2019; 20:1029-1040. [DOI: 10.2174/1389450120666190214141626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 02/01/2023]
Abstract
Background:One of the important factors in Low-Density Lipoprotein (LDL) metabolism is the LDL receptor (LDLR) by its capacity to bind and subsequently clear cholesterol derived from LDL (LDL-C) in the circulation. Proprotein Convertase Subtilisin-like Kexin type 9 (PCSK9) is a newly discovered serine protease that destroys LDLR in the liver and thereby controls the levels of LDL in plasma. Inhibition of PCSK9-mediated degradation of LDLR has, therefore, become a novel target for lipid-lowering therapy.Methods:We review the current understanding of the structure and function of PCSK9 as well as its implications for the treatment of hyperlipidemia and atherosclerosis.Results:New treatments such as monoclonal antibodies against PCSK9 may be useful agents to lower plasma levels of LDL and hence prevent atherosclerosis.Conclusion:PCSK9's mechanism of action is not yet fully clarified. However, treatments that target PCSK9 have shown striking early efficacy and promise to improve the lives of countless patients with hyperlipidemia and atherosclerosis.
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Affiliation(s)
- Xinjie Lu
- The Mary and Garry Weston Molecular Immunology Laboratory, Thrombosis Research Institute, London, SW3 6LR, United Kingdom
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10
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Böttcher-Friebertshäuser E, Garten W, Klenk HD. Characterization of Proprotein Convertases and Their Involvement in Virus Propagation. ACTIVATION OF VIRUSES BY HOST PROTEASES 2018. [PMCID: PMC7122180 DOI: 10.1007/978-3-319-75474-1_9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Wolfgang Garten
- Institut für Virologie, Philipps Universität, Marburg, Germany
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11
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Chen S, Wang H, Li H, Zhang Y, Wu Q. Functional analysis of corin protein domains required for PCSK6-mediated activation. Int J Biochem Cell Biol 2017; 94:31-39. [PMID: 29180304 DOI: 10.1016/j.biocel.2017.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/20/2017] [Accepted: 11/24/2017] [Indexed: 02/08/2023]
Abstract
Atrial natriuretic peptide (ANP) is a cardiac hormone essential for normal blood pressure and cardiac function. Corin is a transmembrane serine protease that activates ANP. Recently, we identified proprotein convertase subtilisin/kexin-6 (PCSK6), also called PACE4, as the long-sought corin activator. Both corin and PCSK6 are expressed in cardiomyocytes, but corin activation occurs only on the cell surface. It remains unknown if cell membrane association is needed for PCSK6 to activate corin. Here we expressed corin deletion mutants in HEK293 cells to analyze the domain structures required for PCSK6-mediated activation. Our results show that soluble corin lacking the transmembrane domain was activated by PCSK6 in the conditioned medium but not intracellularly. Recombinant PCSK6 also activated the soluble corin under cell-free conditions. Moreover, PCSK6-mediated corin activation was not enhanced by cell membrane fractions. These results indicate that cell membrane association is unnecessary for PCSK6 to activate corin. Experiments with monensin that blocks PCSK6 secretion and immunostaining indicated that the soluble corin and PCSK6 were secreted via different intracellular pathways, which may explain the lack of corin activation inside the cell. We also found that the protein domains in the corin pro-peptide region were dispensable for PCSK6-mediated activation and that addition of heparan sulfate and chondroitin sulfate or treatment with heparinase or chondroitinase did not alter corin activation by PCSK6 in HEK293 cells. Together, our results provide important insights into the molecular and cellular mechanisms underlying PCSK6-mediated corin activation that is critical for cardiovascular homeostasis.
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Affiliation(s)
- Shenghan Chen
- From the Human Aging Research Institute and School of Life Science, Nanchang University, Nanchang, China; The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - Hao Wang
- The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - Heng Li
- From the Human Aging Research Institute and School of Life Science, Nanchang University, Nanchang, China
| | - Yue Zhang
- The Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Qingyu Wu
- The Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA; The Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China.
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Nakagawa T, Suzuki-Nakagawa C, Watanabe A, Asami E, Matsumoto M, Nakano M, Ebihara A, Uddin MN, Suzuki F. Site-1 protease is required for the generation of soluble (pro)renin receptor. J Biochem 2017; 161:369-379. [PMID: 28013223 DOI: 10.1093/jb/mvw080] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 11/03/2016] [Indexed: 11/13/2022] Open
Abstract
The extracellular domain of the (pro)renin receptor [(P)RR] is cleaved to generate the soluble form of (P)RR [s(P)RR]. Multiple clinical studies have revealed the association between serum/plasma s(P)RR levels and certain diseases, thereby suggesting a potential role for s(P)RR as a disease biomarker. Here, we investigated whether site-1 protease (S1P) is responsible for cleaving (P)RR to generate s(P)RR. Reduction of endogenous S1P with siRNA attenuated s(P)RR generation in Chinese hamster ovary (CHO) cells exogenously expressing human (P)RR with a C-terminal decahistidine tag [CHO/h(P)RR-10His cells]; conversely, overexpression of S1P by transient transfection increased s(P)RR generation. The S1P inhibitor PF429242 suppressed s(P)RR generation in CHO/h(P)RR-10His and human cervical carcinoma HeLa cells; however, the ADAM inhibitor GM6001 had no effect. The furin inhibitor Dec-RVKR-CMK had no effect on the amount of s(P)RR, but caused a slight increase in the size of the s(P)RR. Moreover, the reversible vesicle-trafficking inhibitor brefeldin A (BFA) enhanced the generation of large-sized s(P)RR; PF429242, but not Dec-RVKR-CMK, suppressed this BFA-induced s(P)RR formation. The size of s(P)RR generated during BFA treatment was reduced after removal of BFA; Dec-RVKR-CMK, but not PF429242, suppressed this conversion. Together, these results suggest that s(P)RR is generated by sequential processing by S1P and furin.
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Affiliation(s)
- Tsutomu Nakagawa
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Chiharu Suzuki-Nakagawa
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Akiko Watanabe
- Department of Applied Life Science, Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Eriko Asami
- Department of Applied Life Science, Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Mizuki Matsumoto
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Mami Nakano
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Akio Ebihara
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Mohammad Nasir Uddin
- Department of Obstetrics & Gynecology, Scott & White Healthcare and Texas A&M Health Science Center College of Medicine, Temple, TX 76508, USA
| | - Fumiaki Suzuki
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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Couture F, Levesque C, Dumulon-Perreault V, Ait-Mohand S, D'Anjou F, Day R, Guérin B. PACE4-based molecular targeting of prostate cancer using an engineered ⁶⁴Cu-radiolabeled peptide inhibitor. Neoplasia 2015; 16:634-43. [PMID: 25220591 PMCID: PMC4235008 DOI: 10.1016/j.neo.2014.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 07/28/2014] [Accepted: 07/31/2014] [Indexed: 01/14/2023] Open
Abstract
The potential of PACE4 as a pharmacological target in prostate cancer has been demonstrated as this proprotein convertase is strongly overexpressed in human prostate cancer tissues and its inhibition, using molecular or pharmacological approaches, results in reduced cell proliferation and tumor progression in mouse tumor xenograft models. We developed a PACE4 high-affinity peptide inhibitor, namely, the multi-leucine (ML), and sought to determine whether this peptide could be exploited for the targeting of prostate cancer for diagnostic or molecular imaging purposes. We conjugated a bifunctional chelator 1,4,7-triazacyclononane-1,4,7- triacetic acid (NOTA) to the ML peptide for copper-64 ((64)Cu) labeling and positron emission tomography (PET)- based prostate cancer detection. Enzyme kinetic assays against recombinant PACE4 showed that the NOTA-modified ML peptide displays identical inhibitory properties compared to the unmodified peptide. In vivo biodistribution of the (64)Cu/NOTA-ML peptide evaluated in athymic nude mice bearing xenografts of two human prostate carcinoma cell lines showed a rapid and high uptake in PACE4-expressing LNCaP tumor at an early time point and in PACE4-rich organs. Co-injection of unlabeled peptide confirmed that tumor uptake was target-specific. PACE4-negative tumors displayed no tracer uptake 15 minutes after injection, while the kidneys, demonstrated high uptake due to rapid renal clearance of the peptide. The present study supports the feasibility of using a (64)Cu/NOTA-ML peptide for PACE4-targeted prostate cancer detection and PACE4 status determination by PET imaging but also provides evidence that ML inhibitor-based drugs would readily reach tumor sites under in vivo conditions for pharmacological intervention or targeted radiation therapy.
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Affiliation(s)
- Frédéric Couture
- Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Christine Levesque
- Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Véronique Dumulon-Perreault
- Centre de Recherche Clinique Étienne-Le Bel, Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Samia Ait-Mohand
- Centre de Recherche Clinique Étienne-Le Bel, Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - François D'Anjou
- Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Robert Day
- Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Université de Sherbrooke, Sherbrooke, Québec, Canada.
| | - Brigitte Guérin
- Centre de Recherche Clinique Étienne-Le Bel, Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Sherbrooke, Québec, Canada.
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Lin YE, Wu QN, Lin XD, Li GQ, Zhang YJ. Expression of paired basic amino acid-cleaving enzyme 4 (PACE4) correlated with prognosis in non-small cell lung cancer (NSCLC) patients. J Thorac Dis 2015; 7:850-60. [PMID: 26101640 DOI: 10.3978/j.issn.2072-1439.2015.05.09] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Accepted: 05/11/2015] [Indexed: 12/27/2022]
Abstract
BACKGROUND Paired basic amino acid-cleaving enzyme 4 (PACE4) was shown to enhance tumor cells proliferation and invasive. This study provides the first investigation of PACE4 expression in non-small cell lung cancer (NSCLC) and the correlation with clinicopathologic features, prognostic indicators of 172 cases. METHODS Quantitative real-time PCR (RT-PCR) and immunofluorescence (IF) were applied to detect PACE4 expression in NSCLC and 16HBE cell lines, then 172 consecutive NSCLC and 15 normal lung tissues were studied through immunohistochemistry (IHC). The association between PACE4 expression and clinicopathological parameters was evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of PACE4 expression on survival. RESULTS PACE4 expression in NSCLC were significantly higher than normal lung cell and tissues (P<0.05). PACE4 had cytoplasmic expression and was observed in 111 of the 172 (64.5%) NSCLC patients. Clinicopathologically, PACE4 expression was significantly associated with lymph node metastasis (N stage) (P=0.007), and clinical stage (P=0.024). Multivariable analysis confirmed that PACE4 expression increased the hazard of death after adjusting for other clinicopathological factors [hazards ratio (HR): 1.584; 95% confidence interval (CI): 1.167-2.151; P<0.001]. Overall survival (OS) was significantly prolonged in PACE4 negative group when compared with PACE4 positive group (5-year survival rates, 23.1% vs. 54.5%, log-rank test, χ(2)=17.717, P<0.001), as was disease-free survival (DFS) (5-year survival rates, 23.4% vs. 55.4%, log-rank test, χ(2)=20.486, P<0.001). CONCLUSIONS Our results suggest that positive expression of PACE4 is an independent factor for NSCLC patients and it might serve as a potential prognostic biomarker for patients with NSCLC.
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Affiliation(s)
- Yun-En Lin
- 1 Department of Pathology, Guangzhou Medical University, Guangzhou 510182, China ; 2 Department of Pathology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Qi-Nian Wu
- 1 Department of Pathology, Guangzhou Medical University, Guangzhou 510182, China ; 2 Department of Pathology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Xiao-Dong Lin
- 1 Department of Pathology, Guangzhou Medical University, Guangzhou 510182, China ; 2 Department of Pathology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Guang-Qiu Li
- 1 Department of Pathology, Guangzhou Medical University, Guangzhou 510182, China ; 2 Department of Pathology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Ya-Jie Zhang
- 1 Department of Pathology, Guangzhou Medical University, Guangzhou 510182, China ; 2 Department of Pathology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
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Construction of a recombinant human insulin expression vector for mammary gland-specific expression in buffalo (Bubalus bubalis) mammary epithelial cell line. Mol Biol Rep 2014; 41:5891-902. [DOI: 10.1007/s11033-014-3464-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 06/14/2014] [Indexed: 11/29/2022]
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Seidah NG, Prat A. The biology and therapeutic targeting of the proprotein convertases. Nat Rev Drug Discov 2012; 11:367-83. [PMID: 22679642 DOI: 10.1038/nrd3699] [Citation(s) in RCA: 588] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The mammalian proprotein convertases constitute a family of nine secretory serine proteases that are related to bacterial subtilisin and yeast kexin. Seven of these (proprotein convertase 1 (PC1), PC2, furin, PC4, PC5, paired basic amino acid cleaving enzyme 4 (PACE4) and PC7) activate cellular and pathogenic precursor proteins by cleavage at single or paired basic residues, whereas subtilisin kexin isozyme 1 (SKI-1) and proprotein convertase subtilisin kexin 9 (PCSK9) regulate cholesterol and/or lipid homeostasis via cleavage at non-basic residues or through induced degradation of receptors. Proprotein convertases are now considered to be attractive targets for the development of powerful novel therapeutics. In this Review, we summarize the physiological functions and pathological implications of the proprotein convertases, and discuss proposed strategies to control some of their activities, including their therapeutic application and validation in selected disease states.
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Affiliation(s)
- Nabil G Seidah
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal (affiliated to University of Montreal), 110 Pine Ave West, Montreal, Quebec H2W 1R7, Canada.
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Malfait AM, Seymour AB, Gao F, Tortorella MD, Le Graverand-Gastineau MPH, Wood LS, Doherty M, Doherty S, Zhang W, Arden NK, Vaughn FL, Leaverton PE, Spector TD, Hart DJ, Maciewicz RA, Muir KR, Das R, Sorge RE, Sotocinal SG, Schorscher-Petcu A, Valdes AM, Mogil JS. A role for PACE4 in osteoarthritis pain: evidence from human genetic association and null mutant phenotype. Ann Rheum Dis 2012; 71:1042-8. [PMID: 22440827 DOI: 10.1136/annrheumdis-2011-200300] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The aim of this study was to assess if genetic variation in the PACE4 (paired amino acid converting enzyme 4) gene Pcsk6 influences the risk for symptomatic knee osteoarthritis (OA). METHODS Ten PCSK6 single nucleotide polymorphisms were tested for association in a discovery cohort of radiographic knee OA (n=156 asymptomatic and 600 symptomatic cases). Meta-analysis of the minor allele at rs900414 was performed in three additional independent cohorts (total n=674 asymptomatic and 2068 symptomatic). Pcsk6 knockout mice and wild-type C57BL/6 mice were compared in a battery of algesiometric assays, including hypersensitivity in response to intraplantar substance P, pain behaviours in response to intrathecal substance P and pain behaviour in the abdominal constriction test. RESULTS In the discovery cohort of radiographic knee OA, an intronic single nucleotide polymorphism at rs900414 was significantly associated with symptomatic OA. Replication in three additional cohorts confirmed that the minor allele at rs900414 was consistently increased among asymptomatic compared to symptomatic radiographic knee OA cases in all four cohorts. A fixed-effects meta-analysis yielded an OR=1.35 (95% CI 1.17 to 1.56; p=4.3×10(-5) and no significant between-study heterogeneity). Studies in mice revealed that Pcsk6 knockout mice were significantly protected against pain in a battery of algesiometric assays. CONCLUSIONS These results suggest that a variant in PCSK6 is strongly associated with protection against pain in knee OA, offering some insight as to why, in the presence of the same structural damage, some individuals develop chronic pain and others are protected. Studies in Pcsk6 null mutant mice further implicate PACE4 in pain.
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Affiliation(s)
- Anne-Marie Malfait
- Department of Biochemistry/ Internal Medicine, Rush University Medical Center, Chicago, Illinois 60612, USA.
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Abstract
The proprotein convertases (PCs) are secretory mammalian serine proteinases related to bacterial subtilisin-like enzymes. The family of PCs comprises nine members, PC1/3, PC2, furin, PC4, PC5/6, PACE4, PC7, SKI-1/S1P, and PCSK9 (Fig. 3.1). While the first seven PCs cleave after single or paired basic residues, the last two cleave at non-basic residues and the last one PCSK9 only cleaves one substrate, itself, for its activation. The targets and substrates of these convertases are very varied covering many aspects of cellular biology and communication. While it took more than 22 years to begin to identify the first member in 1989-1990, in less than 14 years they were all characterized. So where are we 20 years later in 2011? We have now reached a level of maturity needed to begin to unravel the mechanisms behind the complex physiological functions of these PCs both in health and disease states. We are still far away from comprehensively understanding the various ramifications of their roles and to identify their physiological substrates unequivocally. How do these enzymes function in vivo? Are there other partners to be identified that would modulate their activity and/or cellular localization? Would non-toxic inhibitors/silencers of some PCs provide alternative therapies to control some pathologies and improve human health? Are there human SNPs or mutations in these PCs that correlate with disease, and can these help define the finesses of their functions and/or cellular sorting? The more we know about a given field, the more questions will arise, until we are convinced that we have cornered the important angles. And yet the future may well reserve for us many surprises that may allow new leaps in our understanding of the fascinating biology of these phylogenetically ancient eukaryotic proteases (Fig. 3.2) implicated in health and disease, which traffic through the cells via multiple sorting pathways (Fig. 3.3).
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Affiliation(s)
- Nabil G Seidah
- Biochemical Neuroendocrinology Laboratory, Clinical Research Institute of Montreal, Montreal, QC, Canada H2W 1R7.
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20
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In vitro assay for protease activity of proprotein convertase subtilisin kexins (PCSKs): an overall review of existing and new methodologies. Methods Mol Biol 2011; 768:127-53. [PMID: 21805240 DOI: 10.1007/978-1-61779-204-5_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mammalian proprotein convertase subtilisin kexins (PCSKs) previously called proprotein or prohormone convertases (PCs) are a family of Ca(+2)-dependent endoproteases in the subtilisin family. These proteolytic enzymes exert their many crucial physiological and biological functions in vivo via their ability to cleave larger inactive precursor proteins into their biologically active mature forms. This event takes place in a highly efficient and selective manner. Such actions of PCSKs either alone or in combination to cleave specific protein bonds are the hallmark events that not only define the normal functions and metabolism of the body but also may lead to a variety of diseases or disorders with associated conditions. These include among others, diabetes, obesity, cancer, cardiovascular diseases, reproduction abnormalities as well as viral bacterial infections. These conditions were the direct consequences of an enhanced level of enzymatic activity of one or more PCSKs except only PCSK9, whose protease activity in relation to its physiological substrate has yet to be characterized. Owing to this finding, a large number of research studies have been exclusively devoted to develop rapid, efficient and reliable in vitro methods for examining the protease activity of these enzymes. Several assays have been developed to monitor PCSK activity and these are widely used in chemical, biochemical, cellular and animal studies. This review will cover various methodologies and protocols that are currently available in the literature for PCSK activity assays. These include liquid phase methods using fluorogenic, chromogenic and intramolecularly quenched fluorescent substrates as well as a newly developed novel solid phase fluorescence method. This review will also highlight the usefulness of these methodologies and finally a comparative analysis has been made to examine their merits and demerits with some key examples.
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Analyses of PCSK9 post-translational modifications using time-of-flight mass spectrometry. Methods Mol Biol 2011; 768:167-87. [PMID: 21805242 DOI: 10.1007/978-1-61779-204-5_8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Post-translational modification(s) can affect a protein's function - changing its half-life/stability, its protein-protein interactions, biological activity and/or sub-cellular localization. Following translation, a protein can be modified in several ways, including (i) disulfide bridge formation, (ii) chemical conversion of its constituent amino acids (for instance, glutamine can undergo deamidation to glutamic acid), (iii) sulfation, phosphorylation, de/acetylation, and glycosylation (to name a few), (iv) addition of other proteins as occurs during sumoylation and ubiquitination, and (v) proteolytic cleavage(s). There are several techniques available to identify and monitor post-translational modifications of proteins and peptides including mass spectrometry, two-dimensional sodium dodecyl sulfate polyacrylamide electrophoresis (2D-SDS-PAGE), radiolabeling, and immunoblotting. Ciphergen's surface-enhanced laser desorption/ionization time-of-flight mass spectrometer (SELDI-TOF-MS) has been used successfully for protein/peptide profiling in disease states and for the detection of protein/peptide biomarkers (1-4). In this chapter, the secreted proprotein convertase subtilisin/kexin 9 (PCSK9), which we study in our lab, is used to demonstrate coupling of immunoprecipitation with Ciphergen's time-of-flight mass spectrometer and its ProteinChip software to detect and analyze the common post-translational modifications of phosphorylation and glycosylation. The following topics are covered (1): preparation of cell extracts/samples/spent media (2), processing of samples by immunoprecipitation including optimization of conditions and (3) data acquisition by mass spectrometry and its subsequent analyses.
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Mujoomdar ML, Hogan LM, Parlow AF, Nachtigal MW. Pcsk6 mutant mice exhibit progressive loss of ovarian function, altered gene expression, and formation of ovarian pathology. Reproduction 2010; 141:343-55. [PMID: 21183657 DOI: 10.1530/rep-10-0451] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Bioactivation of precursor proteins by members of the proprotein convertase (PC) family is essential for normal reproduction. The Pcsk6 gene is a member of the PC family that is expressed in numerous ovarian cell types including granulosa cells and oocytes. We hypothesized that loss of PCSK6 would produce adverse effects in the mouse ovary. Mice incapable of expressing PCSK6 (Pcsk6(tm1Rob)) were obtained, and reproductive parameters (serum hormones, whelping interval, estrus cyclicity, and fertility) were compared to Pcsk6(+/+) mice. While Pcsk6(tm1Rob) female mice are fertile, they manifest reduced reproductive capacity at an accelerated rate relative to Pcsk6(+/+) mice. Reproductive senescence is typically reached by 9 months of age and is correlated with loss of estrus cyclicity, elevated serum FSH levels, and gross alterations in ovarian morphology. A wide range of ovarian morphologies were identified encompassing mild, such as an apparent reduction in follicle number, to moderate--ovarian atrophy with a complete absence of follicles--to severe, manifesting as normal ovarian structures replaced by benign ovarian tumors, including tubulostromal adenomas. Targeted gene expression profiling highlighted changes in RNA expression of molecules involved in processes such as steroidogenesis, gonadotropin signaling, transcriptional regulation, autocrine/paracrine signaling, cholesterol handling, and proprotein bioactivation. These results show that PCSK6 activity plays a role in maintaining normal cellular and tissue homeostasis in the ovary.
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Affiliation(s)
- Michelle L Mujoomdar
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia B3H 1X5, Canada
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Scerri TS, Brandler WM, Paracchini S, Morris AP, Ring SM, Richardson AJ, Talcott JB, Stein J, Monaco AP. PCSK6 is associated with handedness in individuals with dyslexia. Hum Mol Genet 2010; 20:608-14. [PMID: 21051773 PMCID: PMC3016905 DOI: 10.1093/hmg/ddq475] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Approximately 90% of humans are right-handed. Handedness is a heritable trait, yet the genetic basis is not well understood. Here we report a genome-wide association study for a quantitative measure of relative hand skill in individuals with dyslexia [reading disability (RD)]. The most highly associated marker, rs11855415 (P = 4.7 × 10−7), is located within PCSK6. Two independent cohorts with RD show the same trend, with the minor allele conferring greater relative right-hand skill. Meta-analysis of all three RD samples is genome-wide significant (n = 744, P = 2.0 × 10−8). Conversely, in the general population (n = 2666), we observe a trend towards reduced laterality of hand skill for the minor allele (P = 0.0020). These results provide molecular evidence that cerebral asymmetry and dyslexia are linked. Furthermore, PCSK6 is a protease that cleaves the left–right axis determining protein NODAL. Functional studies of PCSK6 promise insights into mechanisms underlying cerebral lateralization and dyslexia.
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Affiliation(s)
- Thomas S. Scerri
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - William M. Brandler
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Silvia Paracchini
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Andrew P. Morris
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Susan M. Ring
- Department of Social Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Alex J. Richardson
- Department of Social Policy and Social Work, University of Oxford, OX1 2ER, UK
| | - Joel B. Talcott
- School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - John Stein
- Department of Physiology, University of Oxford, Parks Road, Oxford, OX1 3PT, UK and
| | - Anthony P. Monaco
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
- To whom correspondence should be addressed at: Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK. Tel: +44 1865287503; Fax: +44 1865287650;
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Activation and inactivation of the iron hormone hepcidin: Biochemical characterization of prohepcidin cleavage and sequential degradation to N-terminally truncated hepcidin isoforms. Blood Cells Mol Dis 2009; 43:169-79. [DOI: 10.1016/j.bcmd.2009.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 03/25/2009] [Indexed: 01/08/2023]
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25
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Johnsen LJAH. Post-translational modifications of heterologously expressed cholecystokinin in Saccharomyces cerevisiae. Scandinavian Journal of Clinical and Laboratory Investigation 2009. [DOI: 10.1080/clb.61.234.87.92] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Hall T, Fok KF, Liu MM, Zobel JF, Marino MH, Malfait AM, Tortorella MD, Tomasselli AG. A high performance liquid chromatography assay for monitoring proprotein convertase activity. J Chromatogr A 2007; 1148:46-54. [PMID: 17391681 DOI: 10.1016/j.chroma.2007.02.106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 02/19/2007] [Accepted: 02/23/2007] [Indexed: 11/28/2022]
Abstract
A rapid HPLC assay was developed for monitoring the activity of the two proprotein convertases, PACE-4 and furin. Six novel peptide substrates were synthesized containing the minimal PC recognition sequence (Arg-X-X-Arg), as well as tryptophan residue(s) for easy detection. Four of the peptides were cleaved by both PCs and their kinetic parameters determined. Two peptides were not cleaved but were shown to be good negative controls although not inhibitors of either PC. In addition, inhibition curves were plotted and IC(50) values calculated for PACE-4 and furin in the presence of two polyarginine peptides, hexa and deca-D-arginine.
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Affiliation(s)
- Troii Hall
- Pfizer Inc., 700 Chesterfield Parkway West, Chesterfield, MO 63017, USA.
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Tsuji A, Kikuchi Y, Sato Y, Koide S, Yuasa K, Nagahama M, Matsuda Y. A proteomic approach reveals transient association of reticulocalbin-3, a novel member of the CREC family, with the precursor of subtilisin-like proprotein convertase, PACE4. Biochem J 2006; 396:51-9. [PMID: 16433634 PMCID: PMC1449992 DOI: 10.1042/bj20051524] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
SPCs (subtilisin-like proprotein convertases) are a family of seven structurally related serine endoproteases that are involved in the proteolytic activation of proproteins. In an effort to examine the substrate protein for PACE4 (paired basic amino-acid-cleaving enzyme-4), an SPC, a potent protein inhibitor of PACE4, an alpha1-antitrypsin RVRR (Arg-Val-Arg-Arg) variant, was expressed in GH4C1 cells. Ectopic expression of the RVRR variant caused accumulation of the 48 kDa protein in cells. Sequence analysis indicates that the 48 kDa protein is a putative Ca2+-binding protein, RCN-3 (reticulocalbin-3), which had previously been predicted by bioinformatic analysis of cDNA from the human hypothalamus. RCN-3 is a member of the CREC (Cab45/reticulocalbin/ERC45/calumenin) family of multiple EF-hand Ca2+-binding proteins localized to the secretory pathway. The most interesting feature of the RCN-3 sequence is the presence of five Arg-Xaa-Xaa-Arg motifs, which represents the target sequence of SPCs. Biosynthetic studies showed that RCN-3 is transiently associated with proPACE4, but not with mature PACE4. Inhibition of PACE4 maturation by a Ca2+ ionophore resulted in accumulation of the proPACE4-RCN-3 complex in cells. Furthermore, autoactivation and secretion of PACE4 was increased upon co-expression with RCN-3. Our findings suggest that selective and transient association of RCN-3 with the precursor of PACE4 plays an important role in the biosynthesis of PACE4.
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Affiliation(s)
- Akihiko Tsuji
- Department of Biological Science and Technology, Faculty of Engineering, University of Tokushima, 2-1 Minamijosanjima, Tokushima, 770-8506, Japan.
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Bertrand S, Camasses A, Paris M, D. Holland N, Escriva H. Phylogenetic analysis of Amphioxus genes of the proprotein convertase family, including aPC6C, a marker of epithelial fusions during embryology. Int J Biol Sci 2006; 2:125-32. [PMID: 16763672 PMCID: PMC1474147 DOI: 10.7150/ijbs.2.125] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Accepted: 04/22/2006] [Indexed: 11/25/2022] Open
Abstract
The proprotein convertases (PCs) comprise a family of subtilisin-like endoproteases that activate precursor proteins (including, prohormones, growth factors, and adhesion molecules) during their transit through secretory pathways or at the cell surface. To explore the evolution of the PC gene family in chordates, we made a phylogenetic analysis of PC genes found in databases, with special attention to three PC genes of the cephalochordate amphioxus, the closest living invertebrate relative to the vertebrates. Since some vertebrate PC genes are essential for early development, we investigated the expression pattern of the C isoform of the amphioxus PC6 gene (aPC6C). In amphioxus embryos and larvae, aPC6C is expressed at places where epithelia fuse. Several kinds of fusions occur: ectoderm-to-ectoderm during neurulation; mesoderm-to-ectoderm during formation of the preoral ciliated pit; and endoderm-to-ectoderm during formation of the mouth, pharyngeal slits, anus, and external opening of the club-shaped gland. Presumably, at all these sites, aPC6C is activating proteins favoring association between previously disjunct cell populations.
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Affiliation(s)
- Stéphanie Bertrand
- 1. Laboratoire de Biologie Moléculaire de la Cellule, UMR 5161 CNRS/ENS de Lyon, Ecole Normale Supérieure de Lyon, IFR128 BioSciences Lyon-Gerland, 46, Allée d'Italie, 69364 Lyon Cedex 07, France
| | - Alain Camasses
- 2. Laboratoire Arago, UMR 7628, CNRS and University Pierre and Marie Curie, BP 44, F-66651 Banyuls sur Mer, France
| | - Mathilde Paris
- 1. Laboratoire de Biologie Moléculaire de la Cellule, UMR 5161 CNRS/ENS de Lyon, Ecole Normale Supérieure de Lyon, IFR128 BioSciences Lyon-Gerland, 46, Allée d'Italie, 69364 Lyon Cedex 07, France
| | - Nicholas D. Holland
- 3. Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
| | - Hector Escriva
- 2. Laboratoire Arago, UMR 7628, CNRS and University Pierre and Marie Curie, BP 44, F-66651 Banyuls sur Mer, France
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Abstract
The Xenopus egg extract translation system has proved an ideal tool with which to study the biosynthesis of the prohormone convertases. It provides a robust coupled translation/translocation system capable of efficient translocation of any protein containing an N-terminal signal sequence into the lumen of its microsomal membranes, with cotranslational cleavage of the signal peptide. Its main advantage over rival in vitro translation systems is that it will also carry out posttranslational modification of proteins, such as N-glycosylation, and, in the case of the proprotein convertases, support autocatalytic proregion removal. The egg extract also contains an endogenous, acidic pH optimum enzyme activity, suggestive of a proprotein convertase, that can undertake limited proteolysis of precursors containing multibasic processing sites.
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Affiliation(s)
- Kathleen I J Shennan
- Institute of Medical Sciences, School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, UK
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Discovery of the Proprotein Convertases and their Inhibitors. REGULATION OF CARCINOGENESIS, ANGIOGENESIS AND METASTASIS BY THE PROPROTEIN CONVERTASES (PCS) 2006. [PMCID: PMC7122317 DOI: 10.1007/1-4020-5132-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The members of the convertase family play a central role in the processing of various protein precursors ranging from hormones and growth factors to viral envelope proteins and bacterial toxins. The proteolysis of these precursors that occurs at basic residues is mediated by the proprotein convertases (PCs), namely: PC1, PC2, Furin, PACE4, PC4, PC5 and PC7. The proteolysis at non-basic residues is performed by subtilisin/kexin-like isozyme-1 (S1P/SKI-1) and the newly identified neural apoptosis-regulated convertase-1 (NARC-1/PCSK9). These proteases have key roles in many physiological processes and various pathologies including cancer, obesity, diabetes, neurodegenerative diseases and autosomal dominant hypercholesterolermia. Here we summarize the discovery of the proprotein convertases and their inhibitors, discuss their properties, roles, resemblance and differences
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Schuettrumpf J, Herzog RW, Schlachterman A, Kaufhold A, Stafford DW, Arruda VR. Factor IX variants improve gene therapy efficacy for hemophilia B. Blood 2005; 105:2316-23. [PMID: 15550487 DOI: 10.1182/blood-2004-08-2990] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractIntramuscular injection of adeno-associated viral (AAV) vector to skeletal muscle of humans with hemophilia B is safe, but higher doses are required to achieve therapeutic factor IX (F.IX) levels. The efficacy of this approach is hampered by the retention of F.IX in muscle extracellular spaces and by the limiting capacity of muscle to synthesize fully active F.IX at high expression rates. To overcome these limitations, we constructed AAV vectors encoding F.IX variants for muscle- or liver-directed expression in hemophilia B mice. Circulating F.IX levels following intramuscular injection of AAV-F.IX-K5A/V10K, a variant with low-affinity to extracellular matrix, were 2-5 fold higher compared with wild-type (WT) F.IX, while the protein-specific activities remained similar. Expression of F.IX-R338A generated a protein with 2- or 6-fold higher specific activity than F.IX-WT following vector delivery to skeletal muscle or liver, respectively. F.IX-WT and variant forms provide effective hemostasis in vivo upon challenge by tail-clipping assay. Importantly, intramuscular injection of AAV-F.IX variants did not trigger antibody formation to F.IX in mice tolerant to F.IX-WT. These studies demonstrate that F.IX variants provide a promising strategy to improve the efficacy for a variety of gene-based therapies for hemophilia B.
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Affiliation(s)
- Joerg Schuettrumpf
- The Children's Hospital of Philadelphia, 34th St and Civic Center Blvd, Philadelphia, PA 19104, USA
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Wang L, Yang G, Wu X. Identification of the role of a cysteine-rich region of PC6B by determining the enzymatic characteristics of its mutants. Mol Biotechnol 2004; 27:15-22. [PMID: 15122044 DOI: 10.1385/mb:27:1:15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In the proprotein convertases family, mouse PC6B (mPC6B) has a very large cysteine-rich region (CRR), consisting of 22 tandem cysteine-rich (Cys-rich) repeated segments. The role of this region remains elusive. In this report, to get insight on the possible role of the CRR, we constructed four truncated mPC6B mutant genes with 0, 5, 11, and 22 Cys-rich repeated segments remaining; using the baculovirus-expression system and a simple purification method, we obtained four enzyme mutants of mPC6B. By determining their optimal pH and calcium ion concentration for enzymatic activity and their thermal stability, we found that CRR did not affect pH optimum and Ca2+ optimum compared with the p-domain. However, CRR acted as a stabilizing domain in addition to the p-domain. By kinetic analyses of four mutants, we found that the long Cys-rich repeats in the native form of mPC6B reduced its Vmax. These facts suggest that CRR acts as an important part of functional domain.
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Affiliation(s)
- Lie Wang
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, 200031, P.R. China
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Dey A, Norrbom C, Zhu X, Stein J, Zhang C, Ueda K, Steiner DF. Furin and prohormone convertase 1/3 are major convertases in the processing of mouse pro-growth hormone-releasing hormone. Endocrinology 2004; 145:1961-71. [PMID: 14684599 DOI: 10.1210/en.2003-1472] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We investigated the proteolytic processing of mouse pro-GHRH [84 amino acids (aa)] by furin, PC1/3, PC2, and PC5/6A. We created six point mutations in the N- and C-terminal cleavage sites, RXXR decreased and RXRXXR decreased, respectively. The following results were obtained after transient transfection/cotransfection and metabolic pulse-chase labeling studies in several neuroendocrine cells. 1) Furin was the most efficient convertase in cleaving the N-terminal RXXR/RXRR site to generate intermediate I, 12-84aa, whereas PC1/3 was the most potent in processing the C-terminal RXRXXR site to yield mature GHRH, 12-53aa. 2) Both PC1/3 and PC5/6A also processed the N-terminal site but less efficiently than furin. 3) PC2 was much weaker in cleaving the C-terminal site relative to PC1/3 to generate mature GHRH. 4) The Q10R mutant was significantly more susceptible to furin cleavage at the N-terminal site than the wild-type pro-GHRH. And 5) the N- and C-terminal P1 Arg residues, R11 and R54, respectively, were essential for mature GHRH production. We also showed localization of the GHRH immunoreactive peptides in Golgi and secretory granules in neuroendocrine cells by an immunofluorescence assay. We conclude that the efficient production of mature GHRH from pro-GHRH is a stepwise process mediated predominantly by furin at the N-terminal cleavage site followed by PC1/3 at the C terminus.
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Affiliation(s)
- Arunangsu Dey
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60637, USA
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Bisgrove BW, Morelli SH, Yost HJ. Genetics of human laterality disorders: insights from vertebrate model systems. Annu Rev Genomics Hum Genet 2003; 4:1-32. [PMID: 12730129 DOI: 10.1146/annurev.genom.4.070802.110428] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many internal organs in the vertebrate body are asymmetrically oriented along the left-right (L-R) body axis. Organ asymmetry and some components of the molecular signaling pathways that direct L-R development are highly conserved among vertebrate species. Although individuals with full reversal of organ L-R asymmetry (situs inversus totalis) are healthy, significant morbidity and mortality is associated with perturbations in laterality that result in discordant orientation of organ systems and complex congenital heart defects. In humans and other vertebrates, genetic alterations of L-R signaling pathways can result in a wide spectrum of laterality defects. In this review we categorize laterality defects in humans, mice, and zebrafish into specific classes based on altered patterns of asymmetric gene expression, organ situs defects, and midline phenotypes. We suggest that this classification system provides a conceptual framework to help consolidate the disparate laterality phenotypes reported in humans and vertebrate model organisms, thereby refining our understanding of the genetics of L-R development. This approach helps suggest candidate genes and genetic pathways that might be perturbed in human laterality disorders and improves diagnostic criteria.
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Affiliation(s)
- Brent W Bisgrove
- Huntsman Cancer Institute, Center for Children, Department of Oncological Sciences, University of Utah, Salt Lake City, Utah 84112, USA.
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Ueda K, Lipkind GM, Zhou A, Zhu X, Kuznetsov A, Philipson L, Gardner P, Zhang C, Steiner DF. Mutational analysis of predicted interactions between the catalytic and P domains of prohormone convertase 3 (PC3/PC1). Proc Natl Acad Sci U S A 2003; 100:5622-7. [PMID: 12721373 PMCID: PMC156251 DOI: 10.1073/pnas.0631617100] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The subtilisin-like prohormone convertases (PCs) contain an essential downstream domain (P domain), which has been predicted to have a beta-barrel structure that interacts with and stabilizes the catalytic domain (CAT). To assess possible sites of hydrophobic interaction, a series of mutant PC3-enhanced GFP constructs were prepared in which selected nonpolar residues on the surface of CAT were substituted by the corresponding polar residues in subtilisin Carlsberg. To investigate the folding potential of the isolated P domain, signal peptide-P domain-enhanced GFP constructs with mutated andor truncated P domains were also made. All mutants were expressed in betaTC3 cells, and their subcellular localization and secretion were determined. The mutants fell into three main groups: (i) Golgisecreted, (ii) ERnonsecreted, and (iii) apoptosis inducing. The destabilizing CAT mutations indicate that the side chains of V292, T328, L351, Q408, H409, V412, and F441 and nonpolar fragments of the side chains of R405 and W413 form a hydrophobic patch on CAT that interacts with the P domain. We also have found that the P domain can fold independently, as indicated by its secretion. Interestingly, T594, which is near the P domain C terminus, was not essential for P domain secretion but is crucial for the stability of intact PC3. T594V produced a stable enzyme, but T594D did not, which suggests that T594 participates in important hydrophobic interactions within PC3. These findings support our conclusion that the catalytic and P domains contribute to the folding and thermodynamic stability of the convertases through reciprocal hydrophobic interactions.
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Affiliation(s)
- Kazuya Ueda
- Howard Hughes Medical Institute, Department of Biochemistry, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA
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36
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Li QL, Naqvi S, Shen X, Liu YJ, Lindberg I, Friedman TC. Prohormone convertase 2 enzymatic activity and its regulation in neuro-endocrine cells and tissues. REGULATORY PEPTIDES 2003; 110:197-205. [PMID: 12573800 DOI: 10.1016/s0167-0115(02)00207-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We used the fluorometric substrate, pGlu-Arg-Thr-Lys-Arg-MCA and the C-terminal peptide of human 7B2(155-185), a specific inhibitor of prohormone convertase 2 (PC2), to specifically measure the enzymatic activity of the prohormone convertases, PC2. Using lysates from the pancreatic alpha cell line, alphaTC1-6 cells, which contain moderate levels of PC2 enzymatic activity, we determined that the PC2 assay was linear with respect to time of incubation and protein added and had a pH optimum of 5.5 and a calcium optimum of 2.5 mM. Rat pituitary contained high levels of PC2 enzymatic activity, while the hypothalamus and other brain regions contained moderate levels. This enzyme assay was used to document that both mice null for PC2 as well as mice null for the PC2 cofactor, 7B2, had only trace levels of PC2 activity in various brain regions, while mice heterozygous for these alleles had approximately half of the PC2 activity in most brain regions. PC2 enzymatic activity and PC2 mRNA levels were somewhat discordant suggesting that PC2 mRNA levels do not always reflect PC2 enzymatic activity.
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Affiliation(s)
- Qiao-Ling Li
- Division of Endocrinology, Charles R. Drew University of Medicine and Sciences, UCLA School of Medicine, 1731 E. 120th Street, Los Angeles, CA 90059, USA
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Affiliation(s)
- William C Wetsel
- Departments of Psychiatry and Behavioral Sciences, Medicine (Endocrinology), and Cell Biology, Mouse Behavioral and Neuroendocrine Analysis Core Facility, Duke University Medical Center, Durham, NC 27710, USA.
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Gangnon F, Jégou S, Vallarino M, Vieau D, Vaudry H. Molecular characterization of the cDNA and localization of the mRNA encoding the prohormone convertase PC5-A in the European green frog. J Comp Neurol 2003; 456:60-72. [PMID: 12508314 DOI: 10.1002/cne.10485] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The structure and distribution of PC5-A, a prohormone convertase that is thought to be involved in post-translational processing of peptide hormone and neuropeptide precursors, have not been investigated in submammalian vertebrates. In the present study, we characterized the cDNA encoding PC5-A in the European green frog Rana esculenta. The frog PC5-A cDNA encodes a 913-amino acid protein that encompasses a 28-amino acid signal peptide, the Asp/His/Ser catalytic triad found in all serine proteinases of the subtilisin family, and two potential N-linked glycosylation sites located in a C-terminal cysteine-rich domain. Reverse transcriptase polymerase chain reaction amplification showed that PC5-A mRNA is expressed in various organs including the brain, spinal cord, pituitary, lung, liver, intestine, and testis, but not in the stomach and pancreas. The distribution of PC5-A mRNA in the frog brain was studied by in situ hybridization histochemistry. Intense expression was observed in the mitral cellular layer of the olfactory bulb, the nucleus of the diagonal band of Broca, the anterior preoptic area, and the suprachiasmatic and ventral hypothalamic nuclei. The expression pattern of PC5-A mRNA in the central nervous system of anuran amphibians was consistent with the implication of this prohormone convertase in the processing of various neuropeptide precursors.
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Affiliation(s)
- Françoise Gangnon
- European Institute for Peptide Research (IFRMP 23), Laboratory of Cellular and Molecular Neuroendocrinology, INSERM U-413, UA CNRS, University of Rouen, 76821 Mont-Saint-Aignan, France
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Harada N, Shimokawa O, Nagai T, Kato R, Kondoh T, Niikawa N, Matsumoto N. A 4-Mb critical region for intrauterine growth retardation at 15q26. Clin Genet 2002; 62:340-2. [PMID: 12372065 DOI: 10.1034/j.1399-0004.2002.620416.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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41
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Tangrea MA, Bryan PN, Sari N, Orban J. Solution structure of the pro-hormone convertase 1 pro-domain from Mus musculus. J Mol Biol 2002; 320:801-12. [PMID: 12095256 DOI: 10.1016/s0022-2836(02)00543-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solution structure of the mouse pro-hormone convertase (PC) 1 pro-domain was determined using heteronuclear NMR spectroscopy and is the first structure to be obtained for any of the domains in the convertase family. The ensemble of NMR-derived structures shows a well-ordered core consisting of a four-stranded antiparallel beta-sheet with two alpha-helices packed against one side of this sheet. Sequence homology suggests that the other eukaryotic PC pro-domains will have the same overall fold and most of the residues forming the hydrophobic core of PC1 are highly conserved within the PC family. However, some of the core residues are predicted by homology to be replaced by polar amino acid residues in other PC pro-domains and this may help to explain their marginal stability. Interestingly, the folding topology observed here is also seen for the pro-domain of bacterial subtilisin despite little or no sequence homology. Both the prokaryotic and eukaryotic structures have hydrophobic residues clustered on the solvent-accessible surface of their beta-sheets although the individual residue types differ. In the bacterial case this region is buried at the binding interface with the catalytic domain and, in the eukaryotic PC family, these surface residues are conserved. We therefore propose that the hydrophobic patch in the PC1 pro-domain is involved in the binding interface with its cognate catalytic domain in a similar manner to that seen for the bacterial system. The PC1 pro-domain structure also reveals potential mechanisms for the acid-induced dissociation of the complex between pro- and catalytic domains.
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Affiliation(s)
- Michael A Tangrea
- Center for Advanced Research in Biotechnology, University of Maryland Biotechnology Institute, 9600 Gudelsky Drive, Rockville, MD 20850, USA
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42
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Tsuji A, Ikoma T, Hashimoto E, Matsuda Y. Development of selectivity of alpha1-antitrypsin variant by mutagenesis in its reactive site loop against proprotein convertase. A crucial role of the P4 arginine in PACE4 inhibition. Protein Eng Des Sel 2002; 15:123-30. [PMID: 11917148 DOI: 10.1093/protein/15.2.123] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PACE4, furin and PC6 are Ca2+-dependent serine endoproteases that belong to the subtilisin-like proprotein convertase (SPC) family. Recent reports have supported the involvement of these enzymes in processing of growth/differentiation factors, viral replication, activation of bacterial toxins and tumorigenesis, indicating that these enzymes are a fascinating target for therapeutic agents. In this work, we evaluated the sensitivity and selectivity of three rat alpha1-antitrypsin variants which contained RVPR352, AVRR352 and RVRR352, respectively, within their reactive site loop using both inhibition of enzyme activity toward a fluorogenic substrate in vitro and formation of a SDS-stable protease/inhibitor complex ex vivo. The RVPR variant showed relatively broad selectivity, whereas the AVRR and RVRR variants were more selective than the RVPR variant. The AVRR variant inhibited furin and PC6 but not PACE4. This selectivity was further confirmed by complex formation and inhibition of pro-complement C3 processing. On the other hand, although the RVRR variant inhibited both PACE4 and furin effectively, it needed a 600-fold higher concentration than the RVPR variant to inhibit PC6 in vitro. These inhibitors will be useful tools in helping us to understand the roles of PACE4, furin and PC6.
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Affiliation(s)
- Akihiko Tsuji
- Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, 2-1 Minamijosanjima, Tokushima 770-8506, Japan
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Taniguchi T, Kuroda R, Sakurai K, Nagahama M, Wada I, Tsuji A, Matsuda Y. A critical role for the carboxy terminal region of the proprotein convertase, PACE4A, in the regulation of its autocatalytic activation coupled with secretion. Biochem Biophys Res Commun 2002; 290:878-84. [PMID: 11785985 DOI: 10.1006/bbrc.2001.6282] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PACE4A is a member of the mammalian subtilisin-like proprotein convertase family which is responsible for the proteolytic activation of precursors into their biologically active forms. Previously we reported that the maturation of proPACE4A occurs via a intramolecular autoactivation and cleavage of the propeptide is a rate-limiting step for the secretion of PACE4A (Nagahama et al., FEBS Lett. (1998) 434, 155-159). Although PACE4A is a putative secretory enzyme, it matures and is secreted much slower than general secretory proteins. In this study, we investigated the molecular mechanism underlying this slow maturation. The deletion of 25 amino acids at the carboxy terminus is sufficient for a marked acceleration in both the maturation and secretion of PACE4A. The carboxyl-truncated proPACE4A existed only as a monomer-sized form in the endoplasmic reticulum, whereas the wild type of proPACE4A existed in larger forms. Further, the fusion construct of yellow fluorescent protein and the carboxy-terminal sequence of PACE4A associated with the proPACE4A moiety and inhibited maturation. Thus the carboxy terminus of PACE4A functions as a potent autoinhibitor of its activation, resulting in the retention of proPACE4A in the endoplasmic reticulum. These findings indicate that PACE4A activity is highly controlled by a unique system at post-translational level.
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Affiliation(s)
- Takazumi Taniguchi
- Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima, 2-1 Minamijosanjima, Tokushima, 770-8506, Japan
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Dong W, Day R. Gene expression of proprotein convertases in individual rat anterior pituitary cells and their regulation in corticotrophs mediated by glucocorticoids. Endocrinology 2002; 143:254-62. [PMID: 11751617 DOI: 10.1210/endo.143.1.8570] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The subtilisin-like proprotein convertases (SPCs) are a family of serine proteinases that process secreted proteins at single or paired basic residues. Each SPC has been localized in the rat anterior pituitary, implying their importance in precursor processing in this tissue. The cellular distribution of each SPC has not been established in each hormone-producing cell type. We used double labeling in situ hybridization histochemistry to examine the mRNA distribution of five SPCs in relation to corticotrophs, thyrotrophs, lactotrophs, gonadotrophs, and somatotrophs. Our data demonstrated that SPC expression patterns were distinct, with each SPC expressed in more than one cell type. We noted that overlapping SPC expressions were the rule rather than the exception, suggesting potential SPC redundant functions. We examined the effects of adrenalectomy on corticotroph SPC expression. Most corticotrophs expressed SPC1, SPC3, and SPC4, but few corticotrophs expressed SPC2 or SPC6. After adrenalectomy, we observed increased mRNA levels for SPC1, SPC3, SPC4, and SPC6, but not for SPC2, in POMC-positive anterior pituitary cells. These increased levels were reversed by dexamethasone treatment. These data demonstrate the plasticity of SPCs expression in corticotrophs. SPCs may be directly involved in the mammalian stress response and may be important in hypothalamic-pituitary-adrenal axis homeostasis.
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Affiliation(s)
- Weijia Dong
- Département de Pharmacologie, Faculté de Médecine and Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, Québec, Canada J1H 5N4
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Mzhavia N, Qian Y, Feng Y, Che FY, Devi LA, Fricker LD. Processing of proSAAS in neuroendocrine cell lines. Biochem J 2002; 361:67-76. [PMID: 11742530 PMCID: PMC1222280 DOI: 10.1042/0264-6021:3610067] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
ProSAAS, a recently discovered granin-like protein, potently inhibits prohormone convertase (PC)1, and might also perform additional functions. In the present study, the processing of proSAAS was compared in two neuroendocrine cell lines overexpressing this protein: the AtT-20 mouse pituitary corticotrophic line and the PC12 rat adrenal phaeochromocytoma line. The processing of proSAAS was examined by pulse-chase analysis using [(3)H]leucine, by MS, and by chromatography and radioimmunoassay. Various smaller forms of proSAAS were detected, including peptides designated as little SAAS, PEN and big LEN. Because the PC-12 cells used in the present study do not express either PC1 or PC2, the finding that these cells efficiently cleave proSAAS indicates that these cleavages do not require either enzyme. Two of the peptides identified in AtT-20 media represent novel C-terminally truncated forms of PEN. In both cell lines, the secretion of the small proSAAS-derived peptides is stimulated by secretagogues. However, long-term treatment of wild-type AtT-20 cells with two different secretagogues (8-bromo-cAMP and a phorbol ester) does not affect levels of proSAAS mRNA; this treatment significantly increases PC1 mRNA by approx. 60-80%. The lack of co-regulation of proSAAS and PC1 mRNA implies that enzyme activity can be induced without an accompanying increase in the inhibitor. In addition, the finding that the peptides are secreted via the regulated pathway is consistent with the proposal that they may function as neuropeptides.
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Affiliation(s)
- Nino Mzhavia
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, U.S.A
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Bassi DE, Mahloogi H, Al-Saleem L, Lopez De Cicco R, Ridge JA, Klein-Szanto AJ. Elevated furin expression in aggressive human head and neck tumors and tumor cell lines. Mol Carcinog 2001; 31:224-32. [PMID: 11536372 DOI: 10.1002/mc.1057] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pro-protein convertases (PCs) are proteases that recognize and cleave precursor proteins. Furin, a well-studied PC, is ubiquitously expressed, and it has been implicated in many physiological and pathological processes. Some substrates for furin, such as membrane type 1 (MT1) matrix metalloproteinase (MMP), an MMP that activates gelatinase, a collagen-degrading enzyme, are associated with the advanced malignant phenotype. This report examines the expression of furin in carcinoma cell lines of different invasive ability. The levels of furin mRNA and protein correlated with the aggressiveness of tumor cell lines derived from head and neck and lung cancers. Furin expression also was investigated in primary head and neck squamous cell carcinomas (HNSCCs). Furin mRNA was not detected in nonmetastasizing carcinomas. In contrast, furin mRNA was expressed in metastasizing HNSCCs. Immunohistochemistry and Western blot analysis confirmed these results at the protein level. Furin activity was investigated indirectly by evaluating the expression of the pro-form and the processed form of MT1-MMP. Metastasizing HNSCCs showed increased expression of MT1-MMP. Furthermore, pro-MT1-MMP expression was noted in most of the nonmetastasizing HNSCCs analyzed by Western blot, and it was absent in the metastasizing HNSCCs. This finding suggests a lower level of furin-mediated MT1-MMP activation in the less aggressive cancers. These observations indicate that furin plays a role in tumor progression. Its overexpression in more aggressive or metastasizing cancers resulted in increased MMP processing.
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Affiliation(s)
- D E Bassi
- Department of Pathology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
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Dubois CM, Blanchette F, Laprise MH, Leduc R, Grondin F, Seidah NG. Evidence that furin is an authentic transforming growth factor-beta1-converting enzyme. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:305-16. [PMID: 11141505 PMCID: PMC1850265 DOI: 10.1016/s0002-9440(10)63970-3] [Citation(s) in RCA: 178] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Transforming growth factor (TGF)-beta1 plays an essential role in cell growth and differentiation. It is also considered as a gatekeeper of immune homeostasis with gene disruption leading to autoimmune and inflammatory diseases. TGF-beta1 is produced as an inactive precursor polypeptide that can be efficiently secreted but correct proteolytic cleavage is an essential step for its activation. Assessment of the cleavage site has revealed a unique R-H-R-R sequence reminiscent of proprotein convertase (PC) recognition motifs and has previously demonstrated that this PC-like cleavage site is correctly cleaved by furin, a member of the PC family. Here we report that among PC members, furin more closely satisfies the requirements needed to fulfill the role of a genuine TGF-beta1 convertase. Even though six members of the PC family have the ability to cleave TGF-beta1, ectopic expression of alpha(1)-antitrypsin Portland (alpha(1)-AT-PDX), a potent furin inhibitor, blocked 80% of TGF-beta1 processing mediated by endogenous enzymes as demonstrated in an in vitro digestion assay. Genetic complementation of a furin-deficient LoVo cell line with the wild-type gene restores the production of mature and bioactivable TGF-beta1. Moreover, both furin and TGF-beta are coordinately expressed and regulated in vitro and in vivo in the hematopoietic and immune system, an important tissue target. These results demonstrate for the first time that furin is an authentic and adaptive TGF-beta1-converting enzyme whereas other members of the PC family might substitute or supplement furin activity. Our study advances our comprehension of the complexity of the TGF-beta system and should facilitate the development of therapeutically useful TGF-beta inhibitors.
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Affiliation(s)
- C M Dubois
- Immunology Division and Department of Pharmacology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Canada.
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Li QL, Jansen E, Brent GA, Naqvi S, Wilber JF, Friedman TC. Interactions between the prohormone convertase 2 promoter and the thyroid hormone receptor. Endocrinology 2000; 141:3256-66. [PMID: 10965896 DOI: 10.1210/endo.141.9.7674] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The majority of prohormones are cleaved at paired basic residues to generate bioactive hormones by prohormone convertases (PCs). As PC1 and PC2, two neuroendocrine-specific PCs, appear to be the key enzymes capable of processing a variety of prohormones, alterations of PC2 and/or PC1 levels will probably have a profound effect on hormonal homeostasis. We investigated the regulation of PC2 messenger RNA (mRNA) by thyroid hormone using GH3 cells to demonstrate that T3 negatively regulated PC2 mRNA levels in a dose- and time-dependent fashion. Functional analysis of progressive 5'-deletions of the human (h) PC2 promoter luciferase constructs in GH3 cells demonstrated that the regulation probably occurs at the transcriptional level, and that putative negative thyroid hormone response elements were located within the region from -44 to + 137 bp relative to the transcriptional start site. Transient transfections in JEG-3 cells and COS-1 cells showed that the suppressive effect of T3 was equally mediated by the thyroid hormone receptor (TR) isoforms TRalpha1 and TRbeta1. Electrophoretic mobility shift assays using purified TRal and retinoid X receptor-beta protein as well as GH3 nuclear extracts showed that regions from +51 to +71 bp and from +118 to +137 bp of the hPC2 promoter bind to TRalpha1 as both a monomer and a homodimer and with TRalpha1/retinoid X receptor-beta as a heterodimer. Finally, the in vivo regulation of pituitary PC2 mRNA by thyroid status was demonstrated in rats. These results demonstrate that T3 negatively regulates PC2 expression at the transcriptional level and that functional negative thyroid hormone response elements exist in the hPC2 promoter. We postulate that the alterations of PC2 activity may mediate some of the pathophysiological consequences of hypo- or hyperthyroidism.
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Affiliation(s)
- Q L Li
- Department of Medicine, Cedars-Sinai Research Institute, University of California School of Medicine, Los Angeles 90048, USA
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