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Singh DK, Basit A, Rettie AE, Alade N, Thummel K, Prasad B. Characterization of Gla proteoforms and non-Gla peptides of gamma carboxylated proteins: Application to quantification of prothrombin proteoforms in human plasma. Anal Chim Acta 2023; 1284:341972. [PMID: 37996163 PMCID: PMC10789187 DOI: 10.1016/j.aca.2023.341972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/17/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023]
Abstract
Gamma (γ) carboxylation is an essential post-translational modification in vitamin K-dependent proteins (VKDPs), involved in maintaining critical biological homeostasis. Alterations in the abundance or activity of these proteins have pharmacological and pathological consequences. Importantly, low levels of fully γ-carboxylated clotting factors increase plasma des-γ-carboxy precursors resulting in little or no biological activity. Therefore, it is important to characterize the levels of γ-carboxylation that reflect the active state of these proteins. The conventional enzyme-linked immunosorbent assay for protein induced by vitamin K absence or antagonist II (PIVKA-II) quantification uses an antibody that is not applicable to distinguish different γ-carboxylation states. Liquid chromatography-mass spectrometry (LC-MS) approaches have been utilized to distinguish different γ-carboxylated proteoforms, however, these attempts were impeded by poor sensitivity due to spontaneous neutral loss of CO2 and simultaneous cleavage of the backbone bond in the collision cell. In this study, we utilized an alkaline mobile phase in combination with polarity switching (positive and negative ionization modes) to simultaneously identify and quantify γ-carboxylated VKDPs. The method was applied to compare Gla proteomics of prothrombin (FII) in 10 μL plasma samples of healthy control and warfarin-treated adults. We also identified surrogate non-Gla peptides for seven other VKDPs to quantify total (active plus inactive) protein levels. The total protein approach (TPA) was used to quantify absolute levels of the VKDPs in human plasma.
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Affiliation(s)
- Dilip Kumar Singh
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| | - Abdul Basit
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| | - Allan E Rettie
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Nathan Alade
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Kenneth Thummel
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Bhagwat Prasad
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA, USA.
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2
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De Pablo-Moreno JA, Miguel-Batuecas A, Rodríguez-Merchán EC, Liras A. Treatment of congenital coagulopathies, from biologic to biotechnological drugs: The relevance of gene editing (CRISPR/Cas). Thromb Res 2023; 231:99-111. [PMID: 37839151 DOI: 10.1016/j.thromres.2023.10.001] [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: 07/17/2023] [Revised: 09/09/2023] [Accepted: 10/02/2023] [Indexed: 10/17/2023]
Abstract
Congenital coagulopathies have, throughout the history of medicine, been a focus of scientific study and of great interest as they constitute an alteration of one of the most important and conserved pathways of evolution. The first therapeutic strategies developed to address them were aimed at restoring the blood components lost during hemorrhage by administering whole blood or plasma. Later on, the use of cryoprecipitates was a significant breakthrough as it made it possible to decrease the volumes of blood infused. In the 1970' and 80', clotting factor concentrates became the treatment and, from the 1990's to the present day, recombinant factors -with increasingly longer half-lives- have taken over as the treatment of choice for certain coagulopathies in a seamless yet momentous transition from biological to biotechnological drugs. The beginning of this century, however, saw the emergence of new advanced (gene and cell) treatments, which are currently transforming the therapeutic landscape. The possibility to use cells and viruses as well as specific or bispecific antibodies as medicines is likely to spark a revolution in the world of pharmacology where therapies will be individualized and have long-term effects. Specifically, attention is nowadays focused on the development of gene editing strategies, chiefly those based on CRISPR/Cas technology. Rare coagulopathies such as hemophilia A and B, or even ultra-rare ones such as factor V deficiency, could be among those deriving the greatest benefit from these new developments.
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Affiliation(s)
- Juan A De Pablo-Moreno
- Department of Genetic, Physiology and Microbiology, Biology School, Complutense University of Madrid, Spain
| | - Andrea Miguel-Batuecas
- Department of Genetic, Physiology and Microbiology, Biology School, Complutense University of Madrid, Spain
| | - E Carlos Rodríguez-Merchán
- Osteoarticular Surgery Research, Hospital La Paz Institute for Health Research-IdiPAZ (La Paz University Hospital-Autonomous University of Madrid), Spain
| | - Antonio Liras
- Department of Genetic, Physiology and Microbiology, Biology School, Complutense University of Madrid, Spain.
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3
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A genome-wide CRISPR-Cas9 knockout screen identifies FSP1 as the warfarin-resistant vitamin K reductase. Nat Commun 2023; 14:828. [PMID: 36788244 PMCID: PMC9929328 DOI: 10.1038/s41467-023-36446-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/26/2023] [Indexed: 02/16/2023] Open
Abstract
Vitamin K is a vital micronutrient implicated in a variety of human diseases. Warfarin, a vitamin K antagonist, is the most commonly prescribed oral anticoagulant. Patients overdosed on warfarin can be rescued by administering high doses of vitamin K because of the existence of a warfarin-resistant vitamin K reductase. Despite the functional discovery of vitamin K reductase over eight decades ago, its identity remained elusive. Here, we report the identification of warfarin-resistant vitamin K reductase using a genome-wide CRISPR-Cas9 knockout screen with a vitamin K-dependent apoptotic reporter cell line. We find that ferroptosis suppressor protein 1 (FSP1), a ubiquinone oxidoreductase, is the enzyme responsible for vitamin K reduction in a warfarin-resistant manner, consistent with a recent discovery by Mishima et al. FSP1 inhibitor that inhibited ubiquinone reduction and thus triggered cancer cell ferroptosis, displays strong inhibition of vitamin K-dependent carboxylation. Intriguingly, dihydroorotate dehydrogenase, another ubiquinone-associated ferroptosis suppressor protein parallel to the function of FSP1, does not support vitamin K-dependent carboxylation. These findings provide new insights into selectively controlling the physiological and pathological processes involving electron transfers mediated by vitamin K and ubiquinone.
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4
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Rishavy MA, Hallgren KW, Wilson LA, Hiznay JM, Runge KW, Berkner KL. GGCX mutants that impair hemostasis reveal the importance of processivity and full carboxylation to VKD protein function. Blood 2022; 140:1710-1722. [PMID: 35767717 PMCID: PMC9707401 DOI: 10.1182/blood.2021014275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 06/09/2022] [Indexed: 12/14/2022] Open
Abstract
γ-Glutamyl carboxylase (GGCX) generates multiple carboxylated Glus (Glas) in vitamin K-dependent (VKD) proteins that are required for their functions. GGCX is processive, remaining bound to VKD proteins throughout multiple Glu carboxylations, and this study reveals the essentiality of processivity to VKD protein function. GGCX mutants (V255M and S300F) whose combined heterozygosity in a patient causes defective clotting and calcification were studied using a novel assay that mimics in vivo carboxylation. Complexes between variant carboxylases and VKD proteins important to hemostasis (factor IX [FIX]) or calcification (matrix Gla protein [MGP]) were reacted in the presence of a challenge VKD protein that could potentially interfere with carboxylation of the VKD protein in the complex. The VKD protein in the complex with wild-type carboxylase was carboxylated before challenge protein carboxylation occurred and became fully carboxylated. In contrast, the V255M mutant carboxylated both forms at the same time and did not completely carboxylate FIX in the complex. S300F carboxylation was poor with both FIX and MGP. Additional studies analyzed FIX- and MGP-derived peptides containing the Gla domain linked to sequences that mediate carboxylase binding. The total amount of carboxylated peptide generated by the V255M mutant was higher than that of wild-type GGCX; however, the individual peptides were partially carboxylated. Analysis of the V255M mutant in FIX HEK293 cells lacking endogenous GGCX revealed poor FIX clotting activity. This study shows that disrupted processivity causes disease and explains the defect in the patient. Kinetic analyses also suggest that disrupted processivity may occur in wild-type carboxylase under some conditions (eg, warfarin therapy or vitamin K deficiency).
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Affiliation(s)
- Mark A. Rishavy
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
| | - Kevin W. Hallgren
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
| | - Lee A. Wilson
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
| | - James M. Hiznay
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
| | - Kurt W. Runge
- Department of Inflammation and Immunity, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
| | - Kathleen L. Berkner
- Department of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University School of Medicine, Cleveland, OH
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5
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Berkner KL, Runge KW. Vitamin K-Dependent Protein Activation: Normal Gamma-Glutamyl Carboxylation and Disruption in Disease. Int J Mol Sci 2022; 23:5759. [PMID: 35628569 PMCID: PMC9146348 DOI: 10.3390/ijms23105759] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 05/11/2022] [Accepted: 05/14/2022] [Indexed: 12/12/2022] Open
Abstract
Vitamin K-dependent (VKD) proteins undergo an unusual post-translational modification, which is the conversion of specific Glu residues to carboxylated Glu (Gla). Gla generation is required for the activation of VKD proteins, and occurs in the endoplasmic reticulum during their secretion to either the cell surface or from the cell. The gamma-glutamyl carboxylase produces Gla using reduced vitamin K, which becomes oxygenated to vitamin K epoxide. Reduced vitamin K is then regenerated by a vitamin K oxidoreductase (VKORC1), and this interconversion of oxygenated and reduced vitamin K is referred to as the vitamin K cycle. Many of the VKD proteins support hemostasis, which is suppressed during therapy with warfarin that inhibits VKORC1 activity. VKD proteins also impact a broad range of physiologies beyond hemostasis, which includes regulation of calcification, apoptosis, complement, growth control, signal transduction and angiogenesis. The review covers the roles of VKD proteins, how they become activated, and how disruption of carboxylation can lead to disease. VKD proteins contain clusters of Gla residues that form a calcium-binding module important for activity, and carboxylase processivity allows the generation of multiple Glas. The review discusses how impaired carboxylase processivity results in the pseudoxanthoma elasticum-like disease.
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Affiliation(s)
- Kathleen L. Berkner
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine at CWRU, Cleveland, OH 44195, USA
| | - Kurt W. Runge
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine at CWRU, Cleveland, OH 44195, USA;
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6
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Shum W, Zhang BL, Cao AS, Zhou X, Shi SM, Zhang ZY, Gu LY, Shi S. Calcium Homeostasis in the Epididymal Microenvironment: Is Extracellular Calcium a Cofactor for Matrix Gla Protein-Dependent Scavenging Regulated by Vitamins. Front Cell Dev Biol 2022; 10:827940. [PMID: 35252193 PMCID: PMC8893953 DOI: 10.3389/fcell.2022.827940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/19/2022] [Indexed: 12/23/2022] Open
Abstract
In the male reproductive tract, the epididymis is an essential organ for sperm maturation, in which sperm cells acquire mobility and the ability to fertilize oocytes while being stored in a protective microenvironment. Epididymal function involves a specialized luminal microenvironment established by the epithelial cells of epididymal mucosa. Low-calcium concentration is a unique feature of this epididymal luminal microenvironment, its relevance and regulation are, however, incompletely understood. In the rat epididymis, the vitamin D-related calcium-dependent TRPV6-TMEM16A channel-coupler has been shown to be involved in fluid transport, and, in a spatially complementary manner, vitamin K2-related γ-glutamyl carboxylase (GGCX)-dependent carboxylation of matrix Gla protein (MGP) plays an essential role in promoting calcium-dependent protein aggregation. An SNP in the human GGCX gene has been associated with asthenozoospermia. In addition, bioinformatic analysis also suggests the involvement of a vitamin B6-axis in calcium-dependent MGP-mediated protein aggregation. These findings suggest that vitamins interact with calcium homeostasis in the epididymis to ensure proper sperm maturation and male fertility. This review article discusses the regulation mechanisms of calcium homeostasis in the epididymis, and the potential role of vitamin interactions on epididymal calcium homeostasis, especially the role of matrix calcium in the epididymal lumen as a cofactor for the carboxylated MGP-mediated scavenging function.
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Affiliation(s)
- Winnie Shum
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
- Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
- *Correspondence: Winnie Shum,
| | - Bao Li Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
- Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
- NHC Key Lab of Reproduction Regulation, Shanghai Institute for Biomedical and Pharmaceutical Technologies, Reproduction and Development Institution, Fudan University, Shanghai, China
| | - Albert Shang Cao
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Xin Zhou
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Su Meng Shi
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ze Yang Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Lou Yi Gu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Shuo Shi
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, China
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7
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Ghosh S, Oldenburg J, Czogalla-Nitsche KJ. The Role of GRP and MGP in the Development of Non-Hemorrhagic VKCFD1 Phenotypes. Int J Mol Sci 2022; 23:798. [PMID: 35054981 PMCID: PMC8775833 DOI: 10.3390/ijms23020798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/05/2022] [Accepted: 01/08/2022] [Indexed: 11/21/2022] Open
Abstract
Vitamin K dependent coagulation factor deficiency type 1 (VKCFD1) is a rare hereditary bleeding disorder caused by mutations in γ-Glutamyl carboxylase (GGCX) gene. The GGCX enzyme catalyzes the γ-carboxylation of 15 different vitamin K dependent (VKD) proteins, which have function in blood coagulation, calcification, and cell signaling. Therefore, in addition to bleedings, some VKCFD1 patients develop diverse non-hemorrhagic phenotypes such as skin hyper-laxity, skeletal dysmorphologies, and/or cardiac defects. Recent studies showed that GGCX mutations differentially effect γ-carboxylation of VKD proteins, where clotting factors are sufficiently γ-carboxylated, but not certain non-hemostatic VKD proteins. This could be one reason for the development of diverse phenotypes. The major manifestation of non-hemorrhagic phenotypes in VKCFD1 patients are mineralization defects. Therefore, the mechanism of regulation of calcification by specific VKD proteins as matrix Gla protein (MGP) and Gla-rich protein (GRP) in physiological and pathological conditions is of high interest. This will also help to understand the patho-mechanism of VKCFD1 phenotypes and to deduce new treatment strategies. In the present review article, we have summarized the recent findings on the function of GRP and MGP and how these proteins influence the development of non-hemorrhagic phenotypes in VKCFD1 patients.
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Affiliation(s)
- Suvoshree Ghosh
- Institute of Experimental Haematology and Transfusion Medicine, Venusberg Campus 1, University Clinic Bonn, 53127 Bonn, Germany; (S.G.); (J.O.)
| | - Johannes Oldenburg
- Institute of Experimental Haematology and Transfusion Medicine, Venusberg Campus 1, University Clinic Bonn, 53127 Bonn, Germany; (S.G.); (J.O.)
- Center for Rare Diseases Bonn, Venusberg Campus 1, University Clinic Bonn, 53127 Bonn, Germany
| | - Katrin J. Czogalla-Nitsche
- Institute of Experimental Haematology and Transfusion Medicine, Venusberg Campus 1, University Clinic Bonn, 53127 Bonn, Germany; (S.G.); (J.O.)
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8
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Bus K, Szterk A. Relationship between Structure and Biological Activity of Various Vitamin K Forms. Foods 2021; 10:foods10123136. [PMID: 34945687 PMCID: PMC8701896 DOI: 10.3390/foods10123136] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 01/06/2023] Open
Abstract
Vitamin K is involved many biological processes, such as the regulation of blood coagulation, prevention of vascular calcification, bone metabolism and modulation of cell proliferation. Menaquinones (MK) and phylloquinone vary in biological activity, showing different bioavailability, half-life and transport mechanisms. Vitamin K1 and MK-4 remain present in the plasma for 8–24 h, whereas long-chain menaquinones can be detected up to 96 h after administration. Geometric structure is also an important factor that conditions their properties. Cis-phylloquinone shows nearly no biological activity. An equivalent study for menaquinone is not available. The effective dose to decrease uncarboxylated osteocalcin was six times lower for MK-7 than for MK-4. Similarly, MK-7 affected blood coagulation system at dose three to four times lower than vitamin K1. Both vitamin K1 and MK-7 inhibited the decline in bone mineral density, however benefits for the occurrence of cardiovascular diseases have been observed only for long-chain menaquinones. There are currently no guidelines for the recommended doses and forms of vitamin K in the prevention of osteoporosis, atherosclerosis and other cardiovascular disorders. Due to the presence of isomers with unknown biological properties in some dietary supplements, quality and safety of that products may be questioned.
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Affiliation(s)
- Katarzyna Bus
- Department of Spectrometric Methods, National Medicines Institute, 30/34 Chełmska, 00-725 Warsaw, Poland
- Correspondence:
| | - Arkadiusz Szterk
- Center for Translational Medicine, Warsaw University of Life Sciences, Nowoursynowska 100, 02-797 Warsaw, Poland;
- Transfer of Science Sp. z o.o., Strzygłowska 15, 04-866 Warsaw, Poland
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9
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Mokgalaboni K, Nkambule BB, Ntamo Y, Ziqubu K, Nyambuya TM, Mazibuko-Mbeje SE, Gabuza KB, Chellan N, Cirilli I, Tiano L, Dludla PV. Vitamin K: A vital micronutrient with the cardioprotective potential against diabetes-associated complications. Life Sci 2021; 286:120068. [PMID: 34688697 DOI: 10.1016/j.lfs.2021.120068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/12/2021] [Accepted: 10/17/2021] [Indexed: 12/14/2022]
Abstract
Cardiovascular disease (CVD) remains the leading cause of mortality in patients with type 2 diabetes (T2D). The conventional therapies seem to offer minimal long-term cardioprotection against diabetes-related complications in patients living with T2D. There is a growing interest in understanding the therapeutic effects of food-derived bioactive compounds in protecting or managing these metabolic diseases. This includes uncovering the therapeutic potential of fat-soluble micronutrients such as vitamin K, which are abundantly found in green leafy vegetables. We searched the major electronic databases including PubMed, Web of Sciences, Scopus, Google Scholar and Science direct. The search retrieved randomized clinical trials and preclinical studies, reporting on the impact of vitamin K on CVD-related complications in T2D. The current review updates clinical evidence on the therapeutic benefits of vitamin K by attenuating CVD-risk factors such as blood lipid profiles, blood pressure, as well as markers of oxidative stress and inflammation in patients with T2D. Importantly, the summarized preclinical evidence provides a unique perspective into the pathophysiological mechanisms that could be targeted by vitamin K in the primary prevention of T2D-related complications. Lastly, this review further explores the controversies related to the cardioprotective effects of vitamin K, and also provides the basic information such as the source and bioavailability profile of this micronutrient is covered to highlight its therapeutic potential.
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Affiliation(s)
- Kabelo Mokgalaboni
- School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban 4001, South Africa
| | - Bongani B Nkambule
- School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban 4001, South Africa
| | - Yonela Ntamo
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Khanyisani Ziqubu
- Department of Biochemistry, North West University, Mafikeng Campus, Mmabatho 2735, South Africa
| | - Tawanda M Nyambuya
- Department of Health Sciences, Namibia University of Science and Technology, Windhoek 9000, Namibia
| | | | - Kwazikwakhe B Gabuza
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa
| | - Nireshni Chellan
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa; Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg 7505, South Africa
| | - Ilenia Cirilli
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona 60131, Italy; School of Pharmacy, University of Camerino, Camerino 62032, Italy
| | - Luca Tiano
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona 60131, Italy
| | - Phiwayinkosi V Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg 7505, South Africa.
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10
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Ghosh S, Kraus K, Biswas A, Müller J, Forin F, Singer H, Höning K, Hornung V, Watzka M, Oldenburg J, Czogalla-Nitsche KJ. GGCX variants leading to biallelic deficiency to γ-carboxylate GRP cause skin laxity in VKCFD1 patients. Hum Mutat 2021; 43:42-55. [PMID: 34816548 DOI: 10.1002/humu.24300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 09/06/2021] [Accepted: 10/19/2021] [Indexed: 12/17/2022]
Abstract
γ-Glutamyl carboxylase (GGCX) catalyzes the γ-carboxylation of 15 different vitamin K dependent (VKD) proteins. Pathogenic variants in GGCX cause a rare hereditary bleeding disorder called Vitamin K dependent coagulation factor deficiency type 1 (VKCFD1). In addition to bleedings, some VKCFD1 patients develop skin laxity and skeletal dysmorphologies. However, the pathophysiological mechanisms underlying these non-hemorrhagic phenotypes remain elusive. Therefore, we have analyzed 20 pathogenic GGCX variants on their ability to γ-carboxylate six non-hemostatic VKD proteins in an in vitro assay, where GGCX variants were expressed in GGCX-/- cells and levels of γ-carboxylated co-expressed VKD proteins were detected by a functional ELISA. We observed that GGCX variants causing markedly reduced γ-carboxylation of Gla rich protein (GRP) in vitro were reported in patients with skin laxity. Reduced levels of γ-carboxylated Matrix gla protein (MGP) are not exclusive for causing skeletal dysmorphologies in VKCFD1 patients. In silico docking of vitamin K hydroquinone on a GGCX model revealed a binding site, which was validated by in vitro assays. GGCX variants affecting this site result in disability to γ-carboxylate VKD proteins and hence are involved in the most severe phenotypes. This genotype-phenotype analysis will help to understand the development of non-hemorrhagic phenotypes and hence improve treatment in VKCFD1 patients.
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Affiliation(s)
- Suvoshree Ghosh
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Katrin Kraus
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Arijit Biswas
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Jens Müller
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Francesco Forin
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Heike Singer
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Klara Höning
- Unit for Clinical Biochemistry, Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital, University of Bonn, Bonn, Germany
| | - Veit Hornung
- Unit for Clinical Biochemistry, Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital, University of Bonn, Bonn, Germany.,GeneCenter and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Matthias Watzka
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany.,Center for Rare Diseases Bonn, University Clinic Bonn, Bonn, Germany
| | - Johannes Oldenburg
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany.,Center for Rare Diseases Bonn, University Clinic Bonn, Bonn, Germany
| | - Katrin J Czogalla-Nitsche
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
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11
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Chen X, Furukawa N, Jin DY, Liu Y, Stafford DW, Williams CM, Suhara Y, Tie JK. Naturally occurring UBIAD1 mutations differentially affect menaquinone biosynthesis and vitamin K-dependent carboxylation. FEBS J 2021; 289:2613-2627. [PMID: 34813684 PMCID: PMC9064899 DOI: 10.1111/febs.16291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 10/15/2021] [Accepted: 11/22/2021] [Indexed: 11/30/2022]
Abstract
UbiA prenyltransferase domain-containing protein-1 (UBIAD1) is responsible for the biosynthesis of menaquinone-4 (MK-4), a cofactor for extrahepatic carboxylation of vitamin K-dependent (VKD) proteins. Genetic variations of UBIAD1 are mainly associated with Schnyder corneal dystrophy (SCD), a disease characterized by abnormal accumulation of cholesterol in the cornea. Results from in vitro studies demonstrate that SCD-associated UBIAD1 mutations are defective in MK-4 biosynthesis. However, SCD patients do not exhibit typical phenotypes associated with defects of MK-4 or VKD carboxylation. Here, we coupled UBIAD1's biosynthetic activity of MK-4 with VKD carboxylation in HEK293 cells that stably express a chimeric VKD reporter protein. The endogenous Ubiad1 gene in these cells was knocked out by CRISPR-Cas9-mediated genome editing. The effect of UBIAD1 mutations on MK-4 biosynthesis and VKD carboxylation was evaluated in Ubiad1-deficient reporter cells by determining the production of MK-4 or by measuring the efficiency of reporter-protein carboxylation. Our results show that the hot-spot mutation N102S has a moderate impact on MK-4 biosynthesis (retained ˜ 82% activity) but does not affect VKD carboxylation. However, the G186R mutation significantly affected both MK-4 biosynthesis and VKD carboxylation. Other mutations exhibit varying degrees of effects on MK-4 biosynthesis and VKD carboxylation. These results are consistent with in vivo results obtained from gene knock-in mice and SCD patients. Our findings suggest that UBIAD1's MK-4 biosynthetic activity does not directly correlate with the phenotypes of SCD patients. The established cell-based assays in this study provide a powerful tool for the functional studies of UBIAD1 in a cellular milieu.
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Affiliation(s)
- Xuejie Chen
- Department of Biology, University of North Carolina at Chapel Hill, NC, USA
| | - Natsuko Furukawa
- Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Saitama, Japan
| | - Da-Yun Jin
- Department of Biology, University of North Carolina at Chapel Hill, NC, USA
| | - Yizhou Liu
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD, Australia
| | - Darrel W Stafford
- Department of Biology, University of North Carolina at Chapel Hill, NC, USA
| | - Craig M Williams
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD, Australia
| | - Yoshitomo Suhara
- Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Saitama, Japan
| | - Jian-Ke Tie
- Department of Biology, University of North Carolina at Chapel Hill, NC, USA
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12
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Mathonnet A, Cunat S, Allias F, Caillot S, Thonnon C, Till M, Attié-Bitach T, Touraine R, Meunier S, Cartellier C, Rossi M, Attia J, Putoux A. GGCX-related congenital combined vitamin K-dependent clotting factors deficiency-1: Description of a fetus with chondrodysplasia punctata. Am J Med Genet A 2021; 188:314-318. [PMID: 34558179 DOI: 10.1002/ajmg.a.62503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/01/2021] [Accepted: 08/05/2021] [Indexed: 11/06/2022]
Abstract
Congenital combined vitamin K-dependent clotting factors deficiency (VKCFD) is a rare autosomal recessive disease resulting in hemorrhagic symptoms usually associated with developmental disorders and bone abnormalities. Pathogenic variants in two genes encoding enzymes of the vitamin K cycle, GGCX and VKORC1, can lead to this disorder. We present the case of a male fetus with a brachytelephalangic chondrodysplasia punctata (CDP), absence of nasal bone, growth restriction, and bilateral ventriculomegaly at 18 weeks of gestation. Pathological examination showed a Binder phenotype, hypoplastic distal phalanges, stippled epiphyses, and brain abnormalities suggestive of a brain hemorrhage. Two GGCX pathogenic variants inherited respectively from the mother and the father were identified. To our knowledge, this is the first prenatal description of VKCFD. Even if it remains a rare etiology, which is mostly described in children or adult patients, VKCFD should be considered in fetuses with CDP.
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Affiliation(s)
- Alix Mathonnet
- Hospices Civils de Lyon, Centre Pluridisciplinaire de Diagnostic Prénatal, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Séverine Cunat
- Département d'Hématologie Biologique, Hôpital Saint Eloi, Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Fabienne Allias
- Hospices Civils de Lyon, Service d'Anatomo-Pathologie, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Sandrine Caillot
- Hospices Civils de Lyon, Centre Pluridisciplinaire de Diagnostic Prénatal, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Cyrielle Thonnon
- Hospices Civils de Lyon, Centre Pluridisciplinaire de Diagnostic Prénatal, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Marianne Till
- Hospices Civils de Lyon, Service de Génétique, Centre de Référence Anomalies du Développement et Centre de Compétence Maladies Osseuses Constitutionnelles, Groupement Hospitalier Est, Bron, France
| | - Tania Attié-Bitach
- Service d'Histologie-Embryologie-Cytogenetique, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France.,INSERM UMR1163, Imagine Institute, Université de Paris, Paris, France
| | | | - Sandrine Meunier
- Hospices Civils de Lyon, Unité d'Hémostase Clinique, Centre de Référence Maladies Hémorragiques Constitutionnelles (CR-MHC), Hôpital Cardiologique, Bron, France
| | - Charline Cartellier
- Hospices Civils de Lyon, Centre Pluridisciplinaire de Diagnostic Prénatal, Hôpital Femme Mère Enfant, Bron, France
| | - Massimiliano Rossi
- Hospices Civils de Lyon, Service de Génétique, Centre de Référence Anomalies du Développement et Centre de Compétence Maladies Osseuses Constitutionnelles, Groupement Hospitalier Est, Bron, France.,Équipe GENDEV, Centre de Recherche en Neurosciences de Lyon, INSERM U1028 CNRS UMR5292, Université Claude Bernard Lyon 1, Lyon, France
| | - Jocelyne Attia
- Hospices Civils de Lyon, Centre Pluridisciplinaire de Diagnostic Prénatal, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Audrey Putoux
- Hospices Civils de Lyon, Service de Génétique, Centre de Référence Anomalies du Développement et Centre de Compétence Maladies Osseuses Constitutionnelles, Groupement Hospitalier Est, Bron, France.,Équipe GENDEV, Centre de Recherche en Neurosciences de Lyon, INSERM U1028 CNRS UMR5292, Université Claude Bernard Lyon 1, Lyon, France
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13
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Ghosh S, Kraus K, Biswas A, Müller J, Buhl AL, Forin F, Singer H, Höning K, Hornung V, Watzka M, Czogalla-Nitsche KJ, Oldenburg J. GGCX mutations show different responses to vitamin K thereby determining the severity of the hemorrhagic phenotype in VKCFD1 patients. J Thromb Haemost 2021; 19:1412-1424. [PMID: 33590680 DOI: 10.1111/jth.15238] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/22/2020] [Accepted: 01/04/2021] [Indexed: 01/09/2023]
Abstract
BACKGROUND Vitamin K dependent coagulation factor deficiency type 1 (VKCFD1) is a rare hereditary bleeding disorder caused by mutations in γ-glutamyl carboxylase (GGCX). VKCFD1 patients are treated life-long with high doses of vitamin K in order to correct the bleeding phenotype. However, normalization of clotting factor activities cannot be achieved for all VKCFD1 patients. OBJECTIVE The current study aims to investigate the responsiveness to vitamin K for all reported GGCX mutations with respect to clotting factors in order to optimize treatment. METHODS This study developed an assay using genetically engineered GGCX-/- cells, in which GGCX mutations were analyzed with respect to their ability to γ-carboxylate vitamin K dependent pro-coagulatory and anti-coagulatory clotting factors by ELISA. Additionally, factor VII activity was measured in order to proof protein functionality. For specific GGCX mutations immunofluorescent staining was performed to assess the intracellular localization of clotting factors with respect to GGCX wild-type and mutations. RESULTS All GGCX mutations were categorized into responder and low responder mutations, thereby determining the efficiency of vitamin K supplementation. Most VKCFD1 patients have at least one vitamin K responsive GGCX allele that is able to γ-carboxylate clotting factors. In few patients, the hemorrhagic phenotype cannot be reversed by vitamin K administration because GGCX mutations on both alleles affect either structural or catalytically important sites thereby resulting in residual ability to γ-carboxylate clotting factors. CONCLUSION With these new functional data we can predict the hemorrhagic outcome of each VKCFD1 genotype, thus recommending treatments with either vitamin K or prothrombin complex concentrate.
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Affiliation(s)
- Suvoshree Ghosh
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Katrin Kraus
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Arijit Biswas
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Jens Müller
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Anna-Lena Buhl
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Francesco Forin
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Heike Singer
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Klara Höning
- Institute for Clinical Chemistry and Clinical Pharmacology, Unit for Clinical Biochemistry, University Hospital, University of Bonn, Bonn, Germany
| | - Veit Hornung
- Institute for Clinical Chemistry and Clinical Pharmacology, Unit for Clinical Biochemistry, University Hospital, University of Bonn, Bonn, Germany
- GeneCenter and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Matthias Watzka
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
- Center for Rare Diseases Bonn, University Clinic Bonn, Bonn, Germany
| | - Katrin J Czogalla-Nitsche
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - Johannes Oldenburg
- Institute of Experimental Haematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
- Center for Rare Diseases Bonn, University Clinic Bonn, Bonn, Germany
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14
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Pratt VM, Turner A, Broeckel U, Dawson DB, Gaedigk A, Lynnes TC, Medeiros EB, Moyer AM, Requesens D, Vetrini F, Kalman LV. Characterization of Reference Materials with an Association for Molecular Pathology Pharmacogenetics Working Group Tier 2 Status: CYP2C9, CYP2C19, VKORC1, CYP2C Cluster Variant, and GGCX: A GeT-RM Collaborative Project. J Mol Diagn 2021; 23:952-958. [PMID: 34020041 DOI: 10.1016/j.jmoldx.2021.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/26/2021] [Accepted: 04/29/2021] [Indexed: 10/21/2022] Open
Abstract
Pharmacogenetic testing is increasingly available from clinical and research laboratories. However, only a limited number of quality control and other reference materials are currently available for many of the variants that are tested. The Association for Molecular Pathology Pharmacogenetic Work Group has published a series of papers recommending alleles for inclusion in clinical testing. Several of the alleles were not considered for tier 1 because of a lack of reference materials. To address this need, the Division of Laboratory Systems, Centers for Disease Control and Prevention-based Genetic Testing Reference Material (GeT-RM) program, in collaboration with members of the pharmacogenetic testing and research communities and the Coriell Institute for Medical Research, has characterized 18 DNA samples derived from Coriell cell lines. DNA samples were distributed to five volunteer testing laboratories for genotyping using three commercially available and laboratory developed tests. Several tier 2 variants, including CYP2C9∗13, CYP2C19∗35, the CYP2C cluster variant (rs12777823), two variants in VKORC1 (rs61742245 and rs72547529) related to warfarin resistance, and two variants in GGCX (rs12714145 and rs11676382) related to clotting factor activation, were identified among these samples. These publicly available materials complement the pharmacogenetic reference materials previously characterized by the GeT-RM program and will support the quality assurance and quality control programs of clinical laboratories that perform pharmacogenetic testing.
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Affiliation(s)
- Victoria M Pratt
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Amy Turner
- RPRD Diagnostics, Milwaukee, Wisconsin; Department of Pediatrics, Section on Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Ulrich Broeckel
- RPRD Diagnostics, Milwaukee, Wisconsin; Department of Pediatrics, Section on Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - D Brian Dawson
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio; Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio; Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas City, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri
| | - Ty C Lynnes
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Elizabeth B Medeiros
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Ann M Moyer
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | | | - Francesco Vetrini
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Lisa V Kalman
- Division of Laboratory Systems, Centers for Disease Control and Prevention, Atlanta, Georgia.
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15
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Recurrent Intracranial Bleed in 3 Siblings: Short of a Shot of Vitamin K! J Pediatr Hematol Oncol 2021; 43:e580-e582. [PMID: 32404684 DOI: 10.1097/mph.0000000000001833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 04/13/2020] [Indexed: 11/26/2022]
Abstract
We present a family who suffered recurrent sibling losses due to vitamin K deficiency bleed. The index child was asymptomatic at presentation, had normal clinical examination, and was investigated for coagulation disorders in view of previous 3 sibling losses as a result of intracranial hemorrhage. His investigations showed deranged coagulogram and clotting factors' assay. The baby was given vitamin K1 1 mg intramuscularly following which his coagulogram and clotting factors' assay returned to normal. The genetic analysis did not identify any inherited cause of bleeding tendency. The significant family history, exclusive breastfeeding, no diarrhea, failure to thrive or drug use, no prophylaxis with vitamin K at birth, recovery of clotting factors on vitamin K administration, and a corroborative molecular analysis confirmed diagnosis of vitamin K deficiency in the index child. This case gives a strong reminder not to miss birth dose of vitamin K in any neonate.
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16
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Cancela ML, Laizé V, Conceição N, Kempf H, Murshed M. Keutel Syndrome, a Review of 50 Years of Literature. Front Cell Dev Biol 2021; 9:642136. [PMID: 33996798 PMCID: PMC8117146 DOI: 10.3389/fcell.2021.642136] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/16/2021] [Indexed: 11/13/2022] Open
Abstract
Keutel syndrome (KS) is a rare autosomal recessive genetic disorder that was first identified in the beginning of the 1970s and nearly 30 years later attributed to loss-of-function mutations in the gene coding for the matrix Gla protein (MGP). Patients with KS are usually diagnosed during childhood (early onset of the disease), and the major traits include abnormal calcification of cartilaginous tissues resulting in or associated with malformations of skeletal tissues (e.g., midface hypoplasia and brachytelephalangism) and cardiovascular defects (e.g., congenital heart defect, peripheral pulmonary artery stenosis, and, in some cases, arterial calcification), and also hearing loss and mild developmental delay. While studies on Mgp -/- mouse, a faithful model of KS, show that pathologic mineral deposition (ectopic calcification) in cartilaginous and vascular tissues is the primary cause underlying many of these abnormalities, the mechanisms explaining how MGP prevents abnormal calcification remain poorly understood. This has negative implication for the development of a cure for KS. Indeed, at present, only symptomatic treatments are available to treat hypertension and respiratory complications occurring in the KS patients. In this review, we summarize the results published in the last 50 years on Keutel syndrome and present the current status of the knowledge on this rare pathology.
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Affiliation(s)
- M. Leonor Cancela
- Centre of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
- Algarve Biomedical Center, University of Algarve, Faro, Portugal
| | - Vincent Laizé
- Centre of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal
| | - Natércia Conceição
- Centre of Marine Sciences (CCMAR), University of Algarve, Faro, Portugal
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
- Algarve Biomedical Center, University of Algarve, Faro, Portugal
| | - Hervé Kempf
- UMR 7365 CNRS-Université de Lorraine, IMoPA, Vandoeuvre-lès-Nancy, France
| | - Monzur Murshed
- Department of Medicine and Faculty of Dentistry, McGill University, Montreal, QC, Canada
- Shriners Hospital for Children, Montreal, QC, Canada
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17
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Chen X, Liu Y, Furukawa N, Jin DY, Savage GP, Stafford DW, Suhara Y, Williams CM, Tie JK. A novel vitamin K derived anticoagulant tolerant to genetic variations of vitamin K epoxide reductase. J Thromb Haemost 2021; 19:689-700. [PMID: 33314621 PMCID: PMC7925372 DOI: 10.1111/jth.15209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/20/2020] [Accepted: 11/02/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Vitamin K antagonists (VKAs), such as warfarin, have remained the cornerstone of oral anticoagulation therapy in the prevention and treatment of thromboembolism for more than half a century. They function by impairing the biosynthesis of vitamin K-dependent (VKD) clotting factors through the inhibition of vitamin K epoxide reductase (VKOR). The challenge of VKAs therapy is their narrow therapeutic index and highly variable dosing requirements, which are partially the result of genetic variations of VKOR. OBJECTIVES The goal of this study was to search for an improved VKA that is tolerant to the genetic variations of its target enzyme. METHODS A series of vitamin K derivatives with benzyl and related side-chain substitutions at the 3-position of 1,4-naphthoquinone were synthesized. The role of these compounds in VKD carboxylation was evaluated by mammalian cell-based assays and conventional in vitro activity assays. RESULTS Our results showed that replacing the phytyl side-chain with a methylene cyclooctatetraene (COT) moiety at the 3-position of vitamin K1 converted it from a substrate to an inhibitor for VKD carboxylation. Strikingly, this COT-vitamin K derivative displayed a similar inhibition potency in warfarin-resistant VKOR mutations whose warfarin resistance varied more than 400-fold. Further characterization of COT-vitamin K for the inhibition of VKD carboxylation suggested that this compound targets multiple enzymes in the vitamin K redox cycle. Importantly, the anticoagulation effect of COT-vitamin K can be rescued with high doses of vitamin K1 . CONCLUSION We discovered a vitamin K analogue that functions as a VKA and is tolerant to genetic variations in the target enzyme.
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Affiliation(s)
- Xuejie Chen
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Yizhou Liu
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Queensland, Australia
| | - Natsuko Furukawa
- Laboratory of Organic Synthesis and Medicinal Chemistry, Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570, Japan
| | - Da-Yun Jin
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - G. Paul Savage
- CSIRO Manufacturing, Ian Wark Laboratory, Melbourne 3168, Victoria, Australia
| | - Darrel W. Stafford
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Yoshitomo Suhara
- Laboratory of Organic Synthesis and Medicinal Chemistry, Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570, Japan
| | - Craig M. Williams
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Queensland, Australia
| | - Jian-Ke Tie
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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18
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Hao Z, Jin DY, Chen X, Schurgers LJ, Stafford DW, Tie JK. γ-Glutamyl carboxylase mutations differentially affect the biological function of vitamin K-dependent proteins. Blood 2021; 137:533-543. [PMID: 33507293 PMCID: PMC7845004 DOI: 10.1182/blood.2020006329] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/28/2020] [Indexed: 12/14/2022] Open
Abstract
γ-Glutamyl carboxylase (GGCX) is an integral membrane protein that catalyzes posttranslational carboxylation of a number of vitamin K-dependent (VKD) proteins involved in a wide variety of physiologic processes, including blood coagulation, vascular calcification, and bone metabolism. Naturally occurring GGCX mutations are associated with multiple distinct clinical phenotypes. However, the genotype-phenotype correlation of GGCX remains elusive. Here, we systematically examined the effect of all naturally occurring GGCX mutations on the carboxylation of 3 structure-function distinct VKD proteins in a cellular environment. GGCX mutations were transiently introduced into GGCX-deficient human embryonic kidney 293 cells stably expressing chimeric coagulation factor, matrix Gla protein (MGP), or osteocalcin as VKD reporter proteins, and then the carboxylation efficiency of these reporter proteins was evaluated. Our results show that GGCX mutations differentially affect the carboxylation of these reporter proteins and the efficiency of using vitamin K as a cofactor. Carboxylation of these reporter proteins by a C-terminal truncation mutation (R704X) implies that GGCX's C terminus plays a critical role in the binding of osteocalcin but not in the binding of coagulation factors and MGP. This has been confirmed by probing the protein-protein interaction between GGCX and its protein substrates in live cells using bimolecular fluorescence complementation and chemical cross-linking assays. Additionally, using a minigene splicing assay, we demonstrated that several GGCX missense mutations affect GGCX's pre-messenger RNA splicing rather than altering the corresponding amino acid residues. Results from this study interpreted the correlation of GGCX's genotype and its clinical phenotypes and clarified why vitamin K administration rectified bleeding disorders but not nonbleeding disorders.
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Affiliation(s)
- Zhenyu Hao
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Da-Yun Jin
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Xuejie Chen
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Leon J Schurgers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands
| | - Darrel W Stafford
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Jian-Ke Tie
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC; and
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19
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Guillen-Climent S, García-Vázquez A, Silva E, Estebanez A, Cuesta Peredo A, Rengel Ruiz MD, Monteagudo C, Ramón Quiles MD. Pseudoxanthoma elasticum-like syndrome with coagulation deficiency associated with carotid artery hypoplasia and a novel gamma-glutamyl carboxylase gene mutation. Int J Dermatol 2020; 60:e13-e15. [PMID: 32808310 DOI: 10.1111/ijd.15147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/21/2020] [Accepted: 07/27/2020] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - Esmeralda Silva
- Department of Dermatology, Clinical University Hospital of Valencia, Valencia, Spain
| | - Andrea Estebanez
- Department of Dermatology, Clinical University Hospital of Valencia, Valencia, Spain
| | - Ana Cuesta Peredo
- Department of Genetics, Clinical University Hospital of Valencia, Valencia, Spain
| | | | - Carlos Monteagudo
- Department of Pathology, Clinical University Hospital of Valencia, Valencia, Spain.,Department of Pathology, University of Valencia, Valencia, Spain
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20
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Mokgalaboni K, Dludla PV, Nkambule BB. The prophylactic effects of vitamin K supplementation on coagulopathies associated with type 2 diabetes mellitus: A protocol for a systematic review and meta-analysis. Medicine (Baltimore) 2020; 99:e21143. [PMID: 32871982 PMCID: PMC7437854 DOI: 10.1097/md.0000000000021143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 06/05/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The impact of vitamin K in ameliorating diabetes-associated complications, especially those linked with platelet activation and coagulation remains unclear. The current study aims to systematically explore and discuss the available evidence on the impact of vitamin K on the diabetes-cardiovascular disease (CVD)-associated complications. METHODS A systematic review of studies published on the MEDLINE (PubMed), EMBASE, and Google Scholar electronic database will be conducted. The review will include studies published from inception until May 25, 2020, reporting on the effect of vitamin K on CVD-related markers, especially coagulation factors and platelet activation in type 2 diabetes mellitus. Before the full-text screening, all studies will be screened by title, abstract, and keywords. The Downs and Black checklist will be used to assess the quality of the studies. Additionally, the Cochrane collaboration tool will also be used to evaluate the risk of bias across the included studies. Kappa Cohen's calculator will be used to assess the level of agreement between the authors. DISCUSSIONS This systematic review will not require ethical approval, and the results will be distributed through conference and peer-reviewed publications. Our results will assist current and future research scientists on the potential use of vitamin K as a protective therapy against CVD-related complications. SYSTEMATIC REVIEW REGISTRATION This protocol is registered on the International Prospective Register of Systematic Reviews (PROSPERO) registration number: CRD42020151667.
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Affiliation(s)
- Kabelo Mokgalaboni
- School of Laboratory Medicine and Medical Sciences (SLMMS), College of Health Sciences, University of KwaZulu-Natal, Durban
| | - Phiwayinkosi V. Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Bongani B. Nkambule
- School of Laboratory Medicine and Medical Sciences (SLMMS), College of Health Sciences, University of KwaZulu-Natal, Durban
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21
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Vitamin K therapy to reduce bleeding. Blood 2020; 136:780-782. [PMID: 32790852 DOI: 10.1182/blood.2020006563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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22
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Chen X, Li C, Jin DY, Ingram B, Hao Z, Bai X, Stafford DW, Hu K, Tie JK. A cell-based high-throughput screen identifies drugs that cause bleeding disorders by off-targeting the vitamin K cycle. Blood 2020; 136:898-908. [PMID: 32374827 PMCID: PMC7426647 DOI: 10.1182/blood.2019004234] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 04/16/2020] [Indexed: 12/11/2022] Open
Abstract
Drug-induced bleeding disorders contribute to substantial morbidity and mortality. Antithrombotic agents that cause unintended bleeding of obvious cause are relatively easy to control. However, the mechanisms of most drug-induced bleeding disorders are poorly understood, which makes intervention more difficult. As most bleeding disorders are associated with the dysfunction of coagulation factors, we adapted our recently established cell-based assay to identify drugs that affect the biosynthesis of active vitamin K-dependent (VKD) coagulation factors with possible adverse off-target results. The National Institutes of Health (NIH) Clinical Collection (NCC) library containing 727 drugs was screened, and 9 drugs were identified, including the most commonly prescribed anticoagulant warfarin. Bleeding complications associated with most of these drugs have been clinically reported, but the pathogenic mechanisms remain unclear. Further characterization of the 9 top-hit drugs on the inhibition of VKD carboxylation suggests that warfarin, lansoprazole, and nitazoxanide mainly target vitamin K epoxide reductase (VKOR), whereas idebenone, clofazimine, and AM404 mainly target vitamin K reductase (VKR) in vitamin K redox cycling. The other 3 drugs mainly affect vitamin K availability within the cells. The molecular mechanisms underlying the inactivation of VKOR and VKR by these drugs are clarified. Results from both cell-based and animal model studies suggest that the anticoagulation effect of drugs that target VKOR, but not VKR, can be rescued by the administration of vitamin K. These findings provide insights into the prevention and management of drug-induced bleeding disorders. The established cell-based, high-throughput screening approach provides a powerful tool for identifying new vitamin K antagonists that function as anticoagulants.
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Affiliation(s)
- Xuejie Chen
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Caihong Li
- Research Center for Integrative Medicine, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Da-Yun Jin
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Brian Ingram
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Zhenyu Hao
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Xue Bai
- Research Center for Integrative Medicine, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Darrel W Stafford
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
| | - Keping Hu
- Research Center for Integrative Medicine, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Jian-Ke Tie
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC; and
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23
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Gao W, Xu Y, Liu H, Gao M, Cao Q, Wang Y, Cui L, Huang R, Shen Y, Li S, Yang H, Chen Y, Li C, Yu H, Li W, Shen G. Characterization of missense mutations in the signal peptide and propeptide of FIX in hemophilia B by a cell-based assay. Blood Adv 2020; 4:3659-3667. [PMID: 32766856 PMCID: PMC7422117 DOI: 10.1182/bloodadvances.2020002520] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/06/2020] [Indexed: 11/20/2022] Open
Abstract
Many mutations in the signal peptide and propeptide of factor IX (FIX) cause hemophilia B. A FIX variants database reports 28 unique missense mutations in these regions that lead to FIX deficiency, but the underlying mechanism is known only for the mutations on R43 that interfere with propeptide cleavage. It remains unclear how other mutations result in FIX deficiency and why patients carrying the same mutation have different bleeding tendencies. Here, we modify a cell-based reporter assay to characterize the missense mutations in the signal peptide and propeptide of FIX. The results show that the level of secreted conformation-specific reporter (SCSR), which has a functional γ-carboxyglutamate (Gla) domain of FIX, decreases significantly in most mutations. The decreased SCSR level is consistent with FIX deficiency in hemophilia B patients. Moreover, we find that the decrease in the SCSR level is caused by several distinct mechanisms, including interfering with cotranslational translocation into the endoplasmic reticulum, protein secretion, γ-carboxylation of the Gla domain, and cleavage of the signal peptide or propeptide. Importantly, our results also show that the SCSR levels of most signal peptide and propeptide mutations increase with vitamin K concentration, suggesting that the heterogeneity of bleeding tendencies may be related to vitamin K levels in the body. Thus, oral administration of vitamin K may alleviate the severity of bleeding tendencies in patients with missense mutations in the FIX signal peptide and propeptide regions.
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Affiliation(s)
- Wenwen Gao
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Yaqi Xu
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Hongli Liu
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Meng Gao
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Qing Cao
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Yiyi Wang
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Longteng Cui
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Rong Huang
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Yan Shen
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Sanqiang Li
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Haiping Yang
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
- First Affiliated Hospital, Henan University of Science and Technology, Luoyang, People's Republic of China
| | - Yixiang Chen
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
| | - Chaokun Li
- Sino-UK Joint Laboratory for Brain Function and Injury, School of Basic Medical Sciences, and
| | - Haichuan Yu
- Department of Biochemistry and Molecular Biology, School of Medical Laboratory, Xinxiang Medical University, Xinxiang, People's Republic of China; and
| | - Weikai Li
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - Guomin Shen
- Department of Medical Genetics, Institute of Hemostasis and Thrombosis, School of Basic Medical Sciences, and
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Pratt VM, Cavallari LH, Del Tredici AL, Hachad H, Ji Y, Kalman LV, Ly RC, Moyer AM, Scott SA, Whirl-Carrillo M, Weck KE. Recommendations for Clinical Warfarin Genotyping Allele Selection: A Report of the Association for Molecular Pathology and the College of American Pathologists. J Mol Diagn 2020; 22:847-859. [PMID: 32380173 DOI: 10.1016/j.jmoldx.2020.04.204] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 03/18/2020] [Accepted: 04/01/2020] [Indexed: 11/19/2022] Open
Abstract
The goal of the Association for Molecular Pathology (AMP) Clinical Practice Committee's AMP Pharmacogenomics (PGx) Working Group is to define the key attributes of PGx alleles recommended for clinical testing and a minimum set of variants that should be included in clinical PGx genotyping assays. This document series provides recommendations for a minimum panel of variant alleles (tier 1) and an extended panel of variant alleles (tier 2) that will aid clinical laboratories when designing assays for PGx testing. The AMP PGx Working Group considered functional impact of the variants, allele frequencies in multiethnic populations, the availability of reference materials, as well as other technical considerations for PGx testing when developing these recommendations. The ultimate goal is to promote standardization of PGx gene/allele testing across clinical laboratories. These recommendations are not to be interpreted as prescriptive but to provide a reference guide. Of note, a separate article with recommendations for CYP2C9 allele selection was previously developed by the PGx Working Group that can be applied broadly to CYP2C9-related medications. The warfarin allele recommendations in this report incorporate the previous CYP2C9 allele recommendations and additional genes and alleles that are specific to warfarin testing.
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Affiliation(s)
- Victoria M Pratt
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana.
| | - Larisa H Cavallari
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Pharmacotherapy and Translational Research and Center for Pharmacogenomics and Precision Medicine, University of Florida, Gainesville, Florida
| | - Andria L Del Tredici
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Millennium Health, LLC, San Diego, California
| | - Houda Hachad
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Translational Software, Bellevue, Washington
| | - Yuan Ji
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Pathology and ARUP Laboratories, University of Utah School of Medicine, Salt Lake City, Utah
| | - Lisa V Kalman
- Division of Laboratory Systems, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Reynold C Ly
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Ann M Moyer
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Stuart A Scott
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York; Sema4, a Mount Sinai venture, Stamford, Connecticut
| | - Michelle Whirl-Carrillo
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Department of Biomedical Data Science, Stanford University, Stanford, California
| | - Karen E Weck
- The Pharmacogenomics Working Group of the Clinical Practice Committee, Association for Molecular Pathology, Rockville, Maryland; Departments of Pathology and Laboratory Medicine and Genetics, University of North Carolina, Chapel Hill, North Carolina
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25
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Quaglino D, Boraldi F, Lofaro FD. The biology of vascular calcification. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 354:261-353. [PMID: 32475476 DOI: 10.1016/bs.ircmb.2020.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Vascular calcification (VC), characterized by different mineral deposits (i.e., carbonate apatite, whitlockite and hydroxyapatite) accumulating in blood vessels and valves, represents a relevant pathological process for the aging population and a life-threatening complication in acquired and in genetic diseases. Similarly to bone remodeling, VC is an actively regulated process in which many cells and molecules play a pivotal role. This review aims at: (i) describing the role of resident and circulating cells, of the extracellular environment and of positive and negative factors in driving the mineralization process; (ii) detailing the types of VC (i.e., intimal, medial and cardiac valve calcification); (iii) analyzing rare genetic diseases underlining the importance of altered pyrophosphate-dependent regulatory mechanisms; (iv) providing therapeutic options and perspectives.
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Affiliation(s)
- Daniela Quaglino
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy.
| | - Federica Boraldi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
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26
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Basit A, Prasad B, Estergreen JK, Sabath DE, Alade N, Veenstra DL, Rettie AE, Thummel KE. A Novel LC-MS/MS Assay for Quantification of Des-carboxy Prothrombin and Characterization of Warfarin-Induced Changes. Clin Transl Sci 2020; 13:718-726. [PMID: 32004415 PMCID: PMC7359935 DOI: 10.1111/cts.12757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 01/08/2020] [Indexed: 11/29/2022] Open
Abstract
Warfarin is a narrow therapeutic index anticoagulant drug and its use is associated with infrequent but significant adverse bleeding events. The international normalized ratio (INR) is the most commonly used biomarker to monitor and titrate warfarin therapy. However, INR is derived from a functional assay, which determines clotting efficiency at the time of measurement and is susceptible to technical variability. Protein induced by vitamin K antagonist-II (PIVKA-II) has been suggested as a biomarker of long-term vitamin K status, providing mechanistic insights about variation in the functional assay. However, the currently available antibody-based PIVKA-II assay does not inform on the position and number of des-carboxylation sites in prothrombin. The assay presented in this paper provides simultaneous quantification of carboxy and des-carboxy prothrombin that are essential for monitoring early changes in INR and, thus, serves as the superior tool for managing warfarin therapy. Additionally, this assay permits the quantification of total prothrombin level, which is affected by warfarin treatment. Prothrombin recovery from plasma was 95% and the liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was linear (r2 = 0.98) with a dynamic range of 1-100 µg/mL. The assay interday precision was within 20%. A des-carboxy peptide of prothrombin (GNLER) was negatively correlated with active prothrombin (Pearson r = 0.99, P < 0.0001), whereas its association was positively linked with INR values (Pearson r = 0.75, P < 0.015). This novel LC-MS/MS assay for active and inactive prothrombin quantification can be applied to titrate anticoagulant therapy and to monitor the impact of diseases, such as hepatocellular carcinoma on clotting physiology.
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Affiliation(s)
- Abdul Basit
- Department of Pharmaceutics, University of Washington, Seattle, Washington, USA
| | - Bhagwat Prasad
- Department of Pharmaceutics, University of Washington, Seattle, Washington, USA
| | - Joanne K Estergreen
- Departments of Laboratory Medicine and Medicine, University of Washington, Seattle, Washington, USA
| | - Daniel E Sabath
- Departments of Laboratory Medicine and Medicine, University of Washington, Seattle, Washington, USA
| | - Nathan Alade
- Department of Pharmaceutics, University of Washington, Seattle, Washington, USA
| | - David L Veenstra
- Department of Pharmacy, University of Washington, Seattle, Washington, USA
| | - Allan E Rettie
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Kenneth E Thummel
- Department of Pharmaceutics, University of Washington, Seattle, Washington, USA
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27
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Boraldi F, Lofaro FD, Costa S, Moscarelli P, Quaglino D. Rare Co-occurrence of Beta-Thalassemia and Pseudoxanthoma elasticum: Novel Biomolecular Findings. Front Med (Lausanne) 2020; 6:322. [PMID: 32039214 PMCID: PMC6989569 DOI: 10.3389/fmed.2019.00322] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 12/16/2019] [Indexed: 12/18/2022] Open
Abstract
A number of beta-thalassemia patients, independently from the type of beta-thalassemia (β0 or β+) and blood transfusion requirements, may develop, after puberty, dermal, cardiovascular, and ocular complications associated with an ectopic mineralization phenotype similar to that observed in another rare genetic disorder, namely, Pseudoxanthoma elasticum (PXE). To date, the causes of these alterations in beta-thalassemia patients are not known, but it has been suggested that they could be the consequence of oxidative stress-driven epigenetic regulatory mechanisms producing an ABCC6 down-regulation. Since, in the last years, several genes have been associated to the ectopic mineralization phenotype, this study, for the first time, applied, on beta-thalassemia patients with ectopic mineralization phenotype, a multigene testing strategy. Selection of genes to be analyzed was done on the basis of (i) their genetic involvement in calcification diseases or (ii) their role in calcium-phosphate equilibrium. Although, due to the rarity of these conditions, a limited number of patients was analyzed, the detection of pathogenic variants represents the proof of concept that PXE and beta-thalassemia traits co-occur on a genetic basis and that, in addition to causative mutations, functional polymorphisms may further influence connective tissue manifestations. The use of a multigene-based next-generation sequencing represents a useful time- and cost-effective approach, allowing to identify sequence variants that might improve prognostic assessment and better management of these patients, especially in the current era of precision medicine aiming to identify individual optimal care based on a unique personal profile.
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Affiliation(s)
- Federica Boraldi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Sonia Costa
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Pasquale Moscarelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Daniela Quaglino
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
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28
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Abstract
Ca2+ binding proteins (CBP) are of key importance for calcium to play its role as a pivotal second messenger. CBP bind Ca2+ in specific domains, contributing to the regulation of its concentration at the cytosol and intracellular stores. They also participate in numerous cellular functions by acting as Ca2+ transporters across cell membranes or as Ca2+-modulated sensors, i.e. decoding Ca2+ signals. Since CBP are integral to normal physiological processes, possible roles for them in a variety of diseases has attracted growing interest in recent years. In addition, research on CBP has been reinforced with advances in the structural characterization of new CBP family members. In this chapter we have updated a previous review on CBP, covering in more depth potential participation in physiopathological processes and candidacy for pharmacological targets in many diseases. We review intracellular CBP that contain the structural EF-hand domain: parvalbumin, calmodulin, S100 proteins, calcineurin and neuronal Ca2+ sensor proteins (NCS). We also address intracellular CBP lacking the EF-hand domain: annexins, CBP within intracellular Ca2+ stores (paying special attention to calreticulin and calsequestrin), proteins that contain a C2 domain (such as protein kinase C (PKC) or synaptotagmin) and other proteins of interest, such as regucalcin or proprotein convertase subtisilin kexins (PCSK). Finally, we summarise the latest findings on extracellular CBP, classified according to their Ca2+ binding structures: (i) EF-hand domains; (ii) EGF-like domains; (iii) ɣ-carboxyl glutamic acid (GLA)-rich domains; (iv) cadherin domains; (v) Ca2+-dependent (C)-type lectin-like domains; (vi) Ca2+-binding pockets of family C G-protein-coupled receptors.
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29
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Vitamin K2-Dependent GGCX and MGP Are Required for Homeostatic Calcium Regulation of Sperm Maturation. iScience 2019; 14:210-225. [PMID: 30981116 PMCID: PMC6461585 DOI: 10.1016/j.isci.2019.03.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 02/12/2019] [Accepted: 03/26/2019] [Indexed: 01/05/2023] Open
Abstract
A low-calcium microenvironment is essential for spermatozoa to mature in the epididymis; however, it remains unclear how dysregulation of epididymal luminal calcium is associated with male infertility. Using a warfarin-induced vitamin K2 deficiency rat model, we found that vitamin-K-dependent γ-glutamyl carboxylase (GGCX) and matrix Gla protein (MGP) were essential in extracellular calcium signaling of the intercellular communication required for epididymal sperm maturation. We found that GGCX and MGP co-localized in the vesicular structures of epididymal cells and spermatozoa. Calcium-regulated MGP binds to proteins in a biphasic manner; sub-millimolar calcium enhances, whereas excessive calcium inhibits, the binding. Bioinformatic analysis of the calcium-dependent MGP-bound proteome revealed that vesicle-mediated transport and membrane trafficking underlie the intercellular communication networks. We also identified an SNP mutation, rs699664, in the GGCX gene of infertile men with asthenozoospermia. Overall, we revealed that the GGCX-MGP system is integrated with the intercellular calcium signaling to promote sperm maturation. Epididymal sperm maturation requires VK2-dependent GGCX-mediated MGP carboxylation A GGCX SNP mutation is found in infertile men suffering from asthenozoospermia Carboxylated-MGP regulates intercellular calcium signaling in the epididymal lumen Calcium-regulated MGP binds to proteins in a biphasic-manner and favors low levels
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30
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Abstract
Vitamin K (VK) is an essential cofactor for the post-translational conversion of peptide-bound glutamate to γ-carboxyglutamate. The resultant vitamin K-dependent proteins are known or postulated to possess a variety of biological functions, chiefly in the maintenance of hemostasis. The vitamin K cycle is a cellular pathway that drives γ-carboxylation and recycling of VK via γ-carboxyglutamyl carboxylase (GGCX) and vitamin K epoxide reductase (VKOR), respectively. In this review, we show how novel molecular biological approaches are providing new insights into the pathophysiological mechanisms caused by rare mutations of both GGCX and VKOR. We also discuss how other protein regulators influence the intermediary metabolism of VK, first through intestinal absorption and second through a pathway that converts some dietary phylloquinone to menadione, which is prenylated to menaquinone-4 (MK-4) in target tissues by UBIAD1. The contribution of MK-4 synthesis to VK functions is yet to be revealed.
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Affiliation(s)
- Martin J Shearer
- Centre for Haemostasis and Thrombosis, Guy's and St Thomas' NHS Foundation Trust, London SE1 7EH, United Kingdom;
| | - Toshio Okano
- Department of Hygienic Sciences, Kobe Pharmaceutical University, Kobe 658-8558 Japan;
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31
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Justice ED, Barnum SJ, Kidd T. The WAGR syndrome gene PRRG4 is a functional homologue of the commissureless axon guidance gene. PLoS Genet 2017; 13:e1006865. [PMID: 28859078 PMCID: PMC5578492 DOI: 10.1371/journal.pgen.1006865] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/11/2017] [Indexed: 01/20/2023] Open
Abstract
WAGR syndrome is characterized by Wilm's tumor, aniridia, genitourinary abnormalities and intellectual disabilities. WAGR is caused by a chromosomal deletion that includes the PAX6, WT1 and PRRG4 genes. PRRG4 is proposed to contribute to the autistic symptoms of WAGR syndrome, but the molecular function of PRRG4 genes remains unknown. The Drosophila commissureless (comm) gene encodes a short transmembrane protein characterized by PY motifs, features that are shared by the PRRG4 protein. Comm intercepts the Robo axon guidance receptor in the ER/Golgi and targets Robo for degradation, allowing commissural axons to cross the CNS midline. Expression of human Robo1 in the fly CNS increases midline crossing and this was enhanced by co-expression of PRRG4, but not CYYR, Shisa or the yeast Rcr genes. In cell culture experiments, PRRG4 could re-localize hRobo1 from the cell surface, suggesting that PRRG4 is a functional homologue of Comm. Comm is required for axon guidance and synapse formation in the fly, so PRRG4 could contribute to the autistic symptoms of WAGR by disturbing either of these processes in the developing human brain.
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Affiliation(s)
- Elizabeth D. Justice
- Department of Biology/ms 314, University of Nevada, Reno, Nevada, United States of America
| | - Sarah J. Barnum
- Department of Biology/ms 314, University of Nevada, Reno, Nevada, United States of America
| | - Thomas Kidd
- Department of Biology/ms 314, University of Nevada, Reno, Nevada, United States of America
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Marulanda J, Eimar H, McKee MD, Berkvens M, Nelea V, Roman H, Borrás T, Tamimi F, Ferron M, Murshed M. Matrix Gla protein deficiency impairs nasal septum growth, causing midface hypoplasia. J Biol Chem 2017; 292:11400-11412. [PMID: 28487368 PMCID: PMC5500805 DOI: 10.1074/jbc.m116.769802] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 05/01/2017] [Indexed: 12/31/2022] Open
Abstract
Genetic and environmental factors may lead to abnormal growth of the orofacial skeleton, affecting the overall structure of the face. In this study, we investigated the craniofacial abnormalities in a mouse model for Keutel syndrome, a rare genetic disease caused by loss-of-function mutations in the matrix Gla protein (MGP) gene. Keutel syndrome patients show diffuse ectopic calcification of cartilaginous tissues and impaired midface development. Our comparative cephalometric analyses of micro-computed tomography images revealed a severe midface hypoplasia in Mgp-/- mice. In vivo reporter studies demonstrated that the Mgp promoter is highly active at the cranial sutures, cranial base synchondroses, and nasal septum. Interestingly, the cranial sutures of the mutant mice showed normal anatomical features. Although we observed a mild increase in mineralization of the spheno-occipital synchondrosis, it did not reduce the relative length of the cranial base in comparison with total skull length. Contrary to this, we found the nasal septum to be abnormally mineralized and shortened in Mgp-/- mice. Transgenic restoration of Mgp expression in chondrocytes fully corrected the craniofacial anomalies caused by MGP deficiency, suggesting a local role for MGP in the developing nasal septum. Although there was no up-regulation of markers for hypertrophic chondrocytes, a TUNEL assay showed a marked increase in apoptotic chondrocytes in the calcified nasal septum. Transmission electron microscopy confirmed unusual mineral deposits in the septal extracellular matrix of the mutant mice. Of note, the systemic reduction of the inorganic phosphate level was sufficient to prevent abnormal mineralization of the nasal septum in Mgp-/-;Hyp compound mutants. Our work provides evidence that modulation of local and systemic factors regulating extracellular matrix mineralization can be possible therapeutic strategies to prevent ectopic cartilage calcification and some forms of congenital craniofacial anomalies in humans.
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Affiliation(s)
- Juliana Marulanda
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Hazem Eimar
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Marc D McKee
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
- the Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec H3A 0C7, Canada
| | - Michelle Berkvens
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Valentin Nelea
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Hassem Roman
- the Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec H3A 0C7, Canada
- the Division of Experimental Medicine, Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Teresa Borrás
- the Department of Ophthalmology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27516
| | - Faleh Tamimi
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Mathieu Ferron
- the Institut de Recherches Cliniques de Montréal, Montréal, Quebec H2W 1R7, Canada, and
| | - Monzur Murshed
- From the Faculty of Dentistry, McGill University, Montreal, Quebec H3A 1G1, Canada,
- the Division of Experimental Medicine, Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
- the Shriners Hospital for Children, Montreal, Quebec H4A 0A9, Canada
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33
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Molecular basis of the first reported clinical case of congenital combined deficiency of coagulation factors. Blood 2017; 130:948-951. [PMID: 28679738 DOI: 10.1182/blood-2017-05-782367] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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34
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GGCX-Associated Phenotypes: An Overview in Search of Genotype-Phenotype Correlations. Int J Mol Sci 2017; 18:ijms18020240. [PMID: 28125048 PMCID: PMC5343777 DOI: 10.3390/ijms18020240] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 12/21/2016] [Accepted: 01/13/2017] [Indexed: 11/16/2022] Open
Abstract
Gamma-carboxylation, performed by gamma-glutamyl carboxylase (GGCX), is an enzymatic process essential for activating vitamin K-dependent proteins (VKDP) with important functions in various biological processes. Mutations in the encoding GGCX gene are associated with multiple phenotypes, amongst which vitamin K-dependent coagulation factor deficiency (VKCFD1) is best known. Other patients have skin, eye, heart or bone manifestations. As genotype–phenotype correlations were never described, literature was systematically reviewed in search of patients with at least one GGCX mutation with a phenotypic description, resulting in a case series of 47 patients. Though this number was too low for statistically valid correlations—a frequent problem in orphan diseases—we demonstrate the crucial role of the horizontally transferred transmembrane domain in developing cardiac and bone manifestations. Moreover, natural history suggests ageing as the principal determinant to develop skin and eye symptoms. VKCFD1 symptoms seemed more severe in patients with both mutations in the same protein domain, though this could not be linked to a more perturbed coagulation factor function. Finally, distinct GGCX functional domains might be dedicated to carboxylation of very specific VKDP. In conclusion, this systematic review suggests that there indeed may be genotype–phenotype correlations for GGCX-related phenotypes, which can guide patient counseling and management.
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35
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Abstract
Vitamin K-dependent carboxylation, an essential posttranslational modification catalyzed by gamma-glutamyl carboxylase, is required for the biological functions of proteins that control blood coagulation, vascular calcification, bone metabolism, and other important physiological processes. Concomitant with carboxylation, reduced vitamin K (KH2) is oxidized to vitamin K epoxide (KO). KO must be recycled back to KH2 by the enzymes vitamin K epoxide reductase and vitamin K reductase in a pathway known as the vitamin K cycle. Our current knowledge about the enzymes of the vitamin K cycle is mainly based on in vitro studies of each individual enzymes under artificial conditions, which are of limited usefulness in understanding how the complex carboxylation process is carried out in the physiological environment. In this chapter, we review the current in vitro activity assays for vitamin K cycle enzymes. We describe the rationale, establishment, and application of cell-based assays for the functional study of these enzymes in the native cellular milieu. In these cell-based assays, different vitamin K-dependent proteins were designed and stably expressed in mammalian cells as reporter proteins to accommodate the readily used enzyme-linked immunosorbent assay for carboxylation efficiency evaluation. Additionally, recently emerged genome-editing techniques TALENs and CRISPR-Cas9 were used to knock out the endogenous enzymes in the reporter cell lines to eliminate the background. These cell-based assays are easy to scale up for high-throughput screening of inhibitors of vitamin K cycle enzymes and have been successfully used to clarify the genotypes and their clinical phenotypes of enzymes of the vitamin K cycle.
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Affiliation(s)
- J-K Tie
- University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
| | - D W Stafford
- University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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36
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Abstract
In this issue of Blood, Tie et al report the development of a cleverly engineered, cell-based system for studying mutations in γ-glutamyl carboxylase (GGCX), the enzyme responsible for converting glutamate residues in certain proteins to γ-carboxyglutamate (Gla). They use this cell-based assay system to help explain the clinical manifestations of some otherwise puzzling GGCX gene mutations in humans that cause phenotypes ranging from severe bleeding to Keutel syndrome.
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Jin DY, Vermeer C, Stafford DW, Tie JK. Splice-Site Mutation of Exon 3 Deletion in the Gamma-Glutamyl Carboxylase Gene Causes Inactivation of the Enzyme. J Invest Dermatol 2016; 136:2314-2317. [PMID: 27394683 DOI: 10.1016/j.jid.2016.05.128] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 05/04/2016] [Accepted: 05/10/2016] [Indexed: 01/26/2023]
Affiliation(s)
- Da-Yun Jin
- Department of Biology, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Cees Vermeer
- R&D Group VitaK, Maastricht University, Maastricht, The Netherlands
| | - Darrel W Stafford
- Department of Biology, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Jian-Ke Tie
- Department of Biology, University of North Carolina at Chapel Hill, North Carolina, USA.
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Tie JK, Stafford DW. Structural and functional insights into enzymes of the vitamin K cycle. J Thromb Haemost 2016; 14:236-47. [PMID: 26663892 PMCID: PMC5073812 DOI: 10.1111/jth.13217] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/25/2015] [Indexed: 12/20/2022]
Abstract
Vitamin K-dependent proteins require carboxylation of certain glutamates for their biological functions. The enzymes involved in the vitamin K-dependent carboxylation include: gamma-glutamyl carboxylase (GGCX), vitamin K epoxide reductase (VKOR) and an as-yet-unidentified vitamin K reductase (VKR). Due to the hydrophobicity of vitamin K, these enzymes are likely to be integral membrane proteins that reside in the endoplasmic reticulum. Therefore, structure-function studies on these enzymes have been challenging, and some of the results are notably controversial. Patients with naturally occurring mutations in these enzymes, who mainly exhibit bleeding disorders or are resistant to oral anticoagulant treatment, provide valuable information for the functional study of the vitamin K cycle enzymes. In this review, we discuss: (i) the discovery of the enzymatic activities and gene identifications of the vitamin K cycle enzymes; (ii) the identification of their functionally important regions and their active site residues; (iii) the membrane topology studies of GGCX and VKOR; and (iv) the controversial issues regarding the structure and function studies of these enzymes, particularly, the membrane topology, the role of the conserved cysteines and the mechanism of active site regeneration of VKOR. We also discuss the possibility that a paralogous protein of VKOR, VKOR-like 1 (VKORL1), is involved in the vitamin K cycle, and the importance of and possible approaches for identifying the unknown VKR. Overall, we describe the accomplishments and the remaining questions in regard to the structure and function studies of the enzymes in the vitamin K cycle.
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Affiliation(s)
- J-K Tie
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - D W Stafford
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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