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ADAMTS
ADAMTS (short for a disintegrin and metalloproteinase with thrombospondin motifs) is a family of multidomain extracellular protease enzymes. 19 members of this family have been identified in humans, the first of which, ADAMTS1, was described in 1997. Known functions of the ADAMTS proteases include processing of procollagens and von Willebrand factor as well as cleavage of aggrecan, versican, brevican and neurocan, making them key remodeling enzymes of the extracellular matrix. They have been demonstrated to have important roles in connective tissue organization, coagulation, inflammation, arthritis, angiogenesis and cell migration. Homologous subfamily of ADAMTSL (ADAMTS-like) proteins, which lack enzymatic activity, has also been described. Most cases of thrombotic thrombocytopenic purpura arise from autoantibody-mediated inhibition of ADAMTS13. Like ADAMs, the name of the ADAMTS family refers to its disintegrin and metalloproteinase activity, and in the case of ADAMTS, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS4
A disintegrin and metalloproteinase with thrombospondin motifs 4 is an enzyme that in humans is encoded by the ''ADAMTS4'' gene. This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. The enzyme encoded by this gene lacks a C-terminal TS motif. It can degrade aggrecan, a major proteoglycan of cartilage, brevican, a brain-specific extracellular matrix protein, neurocan and versican. The cleavage of aggrecan and brevican suggests key roles of this enzyme in arthritic disease and in the central nervous system, potentially, in the progression of glioma. Structure ADAMTS4 is the shortest known ADAMTS, lacking the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS7
A disintegrin and metalloproteinase with thrombospondin motifs 7 (ADAMTS7) is an enzyme that in humans is encoded by the ''ADAMTS7'' gene on chromosome 15. It is ubiquitously expressed in many tissues and cell types. This enzyme catalyzes the degradation of cartilage oligomeric matrix protein (COMP) degradation. ADAMTS7 has been associated with cancer and arthritis in multiple tissue types. The ''ADAMTS7'' gene also contains one of 27 SNPs associated with increased risk of coronary artery disease. Structure Gene The ''ADAMTS7'' gene resides on chromosome 15 at the band 15q24.2 and contains 25 exons. Protein This 1686-amino acid protein belongs to the ADAMTS family and is one of 19 members known in humans. As an ADAMTS protein, ADAMTS7 contains a shared proteinase domain and an ancillary domain. The proteinase domain can be further divided into a signal peptide, a prodomain, a metalloproteinase domain, and a disintegrin-like domain. In particular, the metalloproteinase domai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS5
A disintegrin and metalloproteinase with thrombospondin motifs 5 also known as ADAMTS5 is an enzyme that in humans is encoded by the ''ADAMTS5'' gene. Function ADAMTS5 is a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. The enzyme encoded by this gene contains two C-terminal TS motifs and functions as aggrecanase to cleave aggrecan, a major proteoglycan of cartilage. ADAMTS5 may also have a role in the pathogenesis of human osteoarthritis. Animal studies Genetically modified mice in which the catalytic domain of ADAMTS5 was deleted are resistant to cartilage destruction in an experimental model of osteoarthritis. ADA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS13
ADAMTS13 (''a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13'')—also known as ''von Willebrand factor-cleaving protease'' (VWFCP)—is a zinc-containing metalloprotease enzyme that cleaves von Willebrand factor (vWf), a large protein involved in blood clotting. It is secreted into the blood and degrades large vWf multimers, decreasing their activity. Genetics The ''ADAMTS13'' gene maps to the ninth chromosome (9q34). Discovery Since 1982 it had been known that thrombotic thrombocytopenic purpura (TTP), one of the microangiopathic hemolytic anemias (see below), was characterized in its familial form by the presence in plasma of unusually large von Willebrand factor multimers (ULVWF). In 1994, vWF was shown to be cleaved between a tyrosine at position 1605 and a methionine at 1606 by a plasma metalloprotease enzyme when it was exposed to high levels of shear stress. In 1996, two research groups independently further characterized this enzy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombotic Thrombocytopenic Purpura
Thrombotic thrombocytopenic purpura (TTP) is a blood disorder that results in blood clots forming in small blood vessels throughout the body. This results in a low platelet count, low red blood cells due to their breakdown, and often kidney, heart, and brain dysfunction. Symptoms may include large bruises, fever, weakness, shortness of breath, confusion, and headache. Repeated episodes may occur. In about half of cases a trigger is identified, while in the remainder the cause remains unknown. Known triggers include bacterial infections, certain medications, autoimmune diseases such as lupus, and pregnancy. The underlying mechanism typically involves antibodies inhibiting the enzyme ADAMTS13. This results in decreased break down of large multimers of von Willebrand factor (vWF) into smaller units. Less commonly TTP is inherited from a person's parents, known as Upshaw–Schulman syndrome, such that ADAMTS13 dysfunction is present from birth. Diagnosis is typically based on s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrombospondin
Thrombospondins (TSPs) are a family of secreted glycoproteins with antiangiogenic functions. Due to their dynamic role within the extracellular matrix they are considered matricellular proteins. The first member of the family, thrombospondin 1 (THBS1), was discovered in 1971 by Nancy L. Baenziger. Types The thrombospondins are a family of multifunctional proteins. The family consists of thrombospondins 1-5 and can be divided into 2 subgroups: A, which contains TSP-1 and TSP-2, and B, which contains TSP-3, TSP-4 and TSP-5 (also designated cartilage oligomeric protein or COMP). TSP-1 and TSP-2 are homotrimers, consisting of three identical subunits, whereas TSP-3, TSP-4 and TSP-5 are homopentamers. TSP-1 and TSP-2 are produced by immature astrocytes during brain development, which promotes the development of new synapses. Thrombospondin 1 Thrombospondin 1 (TSP-1) is encoded by THBS1. It was first isolated from platelets that had been stimulated with thrombin, and so was designa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS2
A disintegrin and metalloproteinase with thrombospondin motifs 2 (ADAM-TS2) also known as procollagen I N-proteinase (PC I-NP) is an enzyme that in humans is encoded by the ''ADAMTS2'' gene. Gene The ADAMTS2 gene is located on the long (q) arm of chromosome 5 at the end (terminus) of the arm, from base pair 178,473,473 to base pair 178,704,934. Function ADAMTS2 is responsible for processing several types of procollagen proteins. Procollagens are the precursors of collagens, the proteins that add strength and support to many body tissues. Specifically, this enzyme clips a short chain of amino acids off one end of the procollagen. This clipping step is necessary for collagen molecules to function normally and assemble into fibrils outside cells. Clinical significance Ehlers-Danlos syndrome, dermatosparaxis type is caused by mutations in the ADAMTS2 gene. Several mutations in the ADAMTS2 gene have been identified in people with this syndrome. These mutations greatly r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS3
A disintegrin and metalloproteinase with thrombospondin motifs 3 is an enzyme that in humans is encoded by the ''ADAMTS3'' gene. The protein encoded by this gene is the major procollagen II N-propeptidase. Structure This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. The protein encoded by this gene is the major procollagen II N-propeptidase. Function Because of the high similarity to ADAMTS2, the major substrate of ADAMTS3 had been erroneously assumed to be procollagen II. However, ADAMTS3 appears largely irrelevant for collagen maturation but instead is required for the activation of the lymphan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS9
A disintegrin and metalloproteinase with thrombospondin motifs 9 is an enzyme that in humans is encoded by the ''ADAMTS9'' gene. This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. Members of the ADAMTS family have been implicated in the cleavage of proteoglycans, the control of organ shape during development, and the inhibition of angiogenesis. This gene is localized to chromosome 3p14.3-p14.2, an area known to be lost in hereditary renal tumors. References Further reading * * * * * * * * * External links * The MEROPS MEROPS is an online database for peptidases (also known as proteases, proteinases a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS8
A disintegrin and metalloproteinase with thrombospondin motifs 8 is an enzyme that in humans is encoded by the ''ADAMTS8'' gene. Function This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS) motif. Individual members of this family differ in the number of C-terminal TS motifs, and some have unique C-terminal domains. The enzyme encoded by this gene contains two C-terminal TS motifs, and disrupts angiogenesis in vivo. Clinical significance A number of disorders have been mapped in the vicinity of this gene, most notably lung neoplasms. References Further reading * * * * * * * * External links * The MEROPS MEROPS is an online database for peptidases (also known as proteases, proteinases and proteolytic enzymes) and thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADAMTS12
A disintegrin and metalloproteinase with thrombospondin motifs 12 is an enzyme that in humans is encoded by the ''ADAMTS12'' gene. This gene encodes a member of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) protein family. Members of the family share several distinct protein modules, including a propeptide region, a metalloproteinase domain, a disintegrin-like domain, and a thrombospondin type 1 (TS-1) motif. Individual members of this family differ in the number of C-terminal TS-1 motifs, and some have unique C-terminal domains. The enzyme encoded by this gene contains eight TS-1 motifs. It may play roles in pulmonary cells during fetal development or in tumor processes through its proteolytic activity or as a molecule potentially involved in regulation of cell adhesion. References Further reading * * * * * * * * External links * The MEROPS MEROPS is an online database for peptidases (also known as proteases, proteinases and proteolytic enz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Von Willebrand Factor
Von Willebrand factor (VWF) () is a blood glycoprotein involved in hemostasis, specifically, platelet adhesion. It is deficient and/or defective in von Willebrand disease and is involved in many other diseases, including thrombotic thrombocytopenic purpura, Heyde's syndrome, and possibly hemolytic–uremic syndrome. Increased plasma levels in many cardiovascular, neoplastic, metabolic (e.g. diabetes), and connective tissue diseases are presumed to arise from adverse changes to the endothelium, and may predict an increased risk of thrombosis. Biochemistry Synthesis VWF is a large multimeric glycoprotein present in blood plasma and produced constitutively as ultra-large VWF in endothelium (in the Weibel–Palade bodies), megakaryocytes (α-granules of platelets), and subendothelial connective tissue. Structure The basic VWF monomer is a 2050-amino acid protein. Every monomer contains a number of specific domains with a specific function; elements of note are: * the D'/D3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |