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Hemojuvelin
Hemojuvelin (HJV), also known as repulsive guidance molecule C (RGMc) or hemochromatosis type 2 protein (HFE2), is a membrane-bound and soluble protein in mammals that is responsible for the iron overload condition known as juvenile hemochromatosis in humans, a severe form of hemochromatosis. In humans, the hemojuvelin protein is encoded by the ''HFE2'' gene. Hemojuvelin is a member of the repulsive guidance molecule family of proteins. Both RGMa and RGMb are found in the nervous system, while hemojuvelin is found in skeletal muscle and the liver. Function For many years the signal transduction pathways that regulate systemic iron homeostasis have been unknown. However it has been demonstrated that hemojuvelin interacts with bone morphogenetic protein (BMP), possibly as a co-receptor, and may signal via the SMAD pathway to regulate hepcidin expression. Associations with BMP2 and BMP4 have been described. Mouse HJV knock-out models confirmed that HJV is the gene responsib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juvenile Hemochromatosis
Juvenile hemochromatosis, also known as hemochromatosis type 2, is a rare form of hereditary hemochromatosis, which emerges in young individuals, typically between 15 and 30 years of age, but occasionally later. It is characterized by an inability to control how much iron is absorbed by the body, in turn leading to iron overload, where excess iron accumulates in many areas of the body and causes damage to the places it accumulates. It is a genetic disorder that can be caused by mutations in either the HJV (also called HFE2) or HAMP genes, and is inherited in an autosomal recessive fashion. Depending on which of these genes is affected, the disease can be further subdivided into types 2A and 2B. Signs and Symptoms The most common symptoms of juvenile hemochromatosis are as follows: * Weakness * Lethargy * Hyperpigmentation (darkening of the skin) * Arthropathy (joint disease) * Diabetes * Heart disease (dilated cardiomyopathy). Complications of heart disease are the main cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RGMB
Repulsive guidance molecule B (RGMb), also known as DRAGON (DRG11-responsive axonal guidance and outgrowth of neurite), is a bone morphogenetic protein (BMP) co-receptor of the repulsive guidance molecule family. In humans this protein is encoded by the ''RGMB'' gene. Function RGMB is a glycosylphosphatidylinositol (GPI)-anchored member of the repulsive guidance molecule family (see also RGMA and RGMC) and contributes to the patterning of the developing nervous system. There is a potential association between RGMs and cancer bone metastasis, as RGMs coordinate bone morphogenetic protein (BMP) signaling. RGMB may act as a negative regulator ''in vitro'' in breast cancer and prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that sur ... through BMP signalling. Furthermore, ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HAMP
Hepcidin is a protein that in humans is encoded by the ''HAMP'' gene. Hepcidin is a key regulator of the entry of iron into the circulation in mammals. During conditions in which the hepcidin level is abnormally high, such as inflammation, serum iron falls due to iron trapping within macrophages and liver cells and decreased gut iron absorption. This typically leads to anemia due to an inadequate amount of serum iron being available for developing red blood cells. When the hepcidin level is abnormally low such as in hemochromatosis, iron overload occurs due to increased ferroportin mediated iron efflux from storage and increased gut iron absorption. Structure Hepcidin exists as a preprohormone (84 amino acids), prohormone (60 amino acids), and hormone (25 amino acids). Twenty- and 22-amino acid metabolites of hepcidin also exist in the urine. Deletion of 5 ''N''-terminal amino acids results in loss of function. The conversion of prohepcidin to hepcidin is mediated by the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepcidin
Hepcidin is a protein that in humans is encoded by the ''HAMP'' gene. Hepcidin is a key regulator of the entry of iron into the circulation in mammals. During conditions in which the hepcidin level is abnormally high, such as inflammation, serum iron falls due to iron trapping within macrophages and liver cells and decreased gut iron absorption. This typically leads to anemia due to an inadequate amount of serum iron being available for developing red blood cells. When the hepcidin level is abnormally low such as in hemochromatosis, iron overload occurs due to increased ferroportin mediated iron efflux from storage and increased gut iron absorption. Structure Hepcidin exists as a preprohormone (84 amino acids), prohormone (60 amino acids), and hormone (25 amino acids). Twenty- and 22-amino acid metabolites of hepcidin also exist in the urine. Deletion of 5 ''N''-terminal amino acids results in loss of function. The conversion of prohepcidin to hepcidin is mediated by the pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RGMA
Repulsive guidance molecule A (RGMa) is a bone morphogenetic protein (BMP) co-receptor of the repulsive guidance molecule family. Together with BMPR1A and BMPR1B, as well as ACVR2A and BMPR2, it binds BMPs thereby activating the intracellular SMAD1/5/8 signalling pathway. In humans this protein is encoded by the ''RGMA'' gene. Function RGMa is a repulsive guidance molecule for retinal axons. Furthermore, neogenin functions as a receptor for RGM. Neogenin overexpression and RGM downexpression in the developing embryonic neural tube induces apoptosis. The apoptotic activity of neogenin in the neural tube is associated with cleavage of its cytoplasmic domain by caspases. RGMA belongs to a family of repulsive guidance molecules that are (glycosylphosphatidylinositol)-linked cell-membrane-associated proteins. The three proteins, RGMa (this protein), RGMb and RGMc are 40-50% identical to each other, and share similarities in predicted protein domains and overall structure. All t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proprotein Convertase
Proprotein convertases (PPCs) are a family of proteins that activate other proteins. Many proteins are inactive when they are first synthesized, because they contain chains of amino acids that block their activity. Proprotein convertases remove those chains and activate the protein. The prototypical proprotein convertase is furin. Proprotein convertases have medical significance, because they are involved in many important biological processes, such as cholesterol synthesis. Compounds called proprotein convertase inhibitors can block their action, and block the target proteins from becoming active. Many proprotein convertases, especially furin and PACE4, are involved in pathological processes such as viral infection, inflammation, hypercholesterolemia, and cancer, and have been postulated as therapeutic targets for some of these diseases. History The phenomenon of prohormone conversion was discovered by Donald F. Steiner while examining the biosynthesis of insulin in 1967. At the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furin
Furin is a protease, a proteolytic enzyme that in humans and other animals is encoded by the ''FURIN'' gene. Some proteins are inactive when they are first synthesized, and must have sections removed in order to become active. Furin cleaves these sections and activates the proteins. It was named furin because it was in the upstream region of an oncogene known as FES. The gene was known as FUR (FES Upstream Region) and therefore the protein was named furin. Furin is also known as PACE (Paired basic Amino acid Cleaving Enzyme). A member of family S8, furin is a subtilisin-like peptidase. Function The protein encoded by this gene is an enzyme that belongs to the subtilisin-like proprotein convertase family. The members of this family are proprotein convertases that process latent precursor proteins into their biologically active products. This encoded protein is a calcium-dependent serine endoprotease that can efficiently cleave precursor proteins at their paired basic amino acid pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
E-box
An E-box (enhancer box) is a DNA response element found in some eukaryotes that acts as a protein-binding site and has been found to regulate gene expression in neurons, muscles, and other tissues. Its specific DNA sequence, CANNTG (where N can be any nucleotide), with a palindromic canonical sequence of CACGTG, is recognized and bound by transcription factors to initiate gene transcription. Once the transcription factors bind to the promoters through the E-box, other enzymes can bind to the promoter and facilitate transcription from DNA to mRNA. Discovery The E-box was discovered in a collaboration between Susumu Tonegawa's and Walter Gilbert's laboratories in 1985 as a control element in immunoglobulin heavy-chain enhancer. They found that a region of 140 base pairs in the tissue-specific transcriptional enhancer element was sufficient for different levels of transcription enhancement in different tissues and sequences. They suggested that proteins made by specific tissues acted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosetta@home
Rosetta@home is a volunteer computing project researching protein structure prediction on the Berkeley Open Infrastructure for Network Computing (BOINC) platform, run by the Baker laboratory at the University of Washington. Rosetta@home aims to predict protein–protein docking and design new proteins with the help of about fifty-five thousand active volunteered computers processing at over 487,946 GigaFLOPS on average as of September 19, 2020. Foldit, a Rosetta@home videogame, aims to reach these goals with a crowdsourcing approach. Though much of the project is oriented toward basic research to improve the accuracy and robustness of proteomics methods, Rosetta@home also does applied research on malaria, Alzheimer's disease, and other pathologies. Like all BOINC projects, Rosetta@home uses idle computer processing resources from volunteers' computers to perform calculations on individual workunits. Completed results are sent to a central project server where they are validate ... [...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 do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosylation
Glycosylation is the reaction in which a carbohydrate (or ' glycan'), i.e. a glycosyl donor, is attached to a hydroxyl or other functional group of another molecule (a glycosyl acceptor) in order to form a glycoconjugate. In biology (but not always in chemistry), glycosylation usually refers to an enzyme-catalysed reaction, whereas glycation (also 'non-enzymatic glycation' and 'non-enzymatic glycosylation') may refer to a non-enzymatic reaction (though in practice, 'glycation' often refers more specifically to Maillard-type reactions). Glycosylation is a form of co-translational and post-translational modification. Glycans serve a variety of structural and functional roles in membrane and secreted proteins. The majority of proteins synthesized in the rough endoplasmic reticulum undergo glycosylation. Glycosylation is also present in the cytoplasm and nucleus as the ''O''-GlcNAc modification. Aglycosylation is a feature of engineered antibodies to bypass glycosylation. Five clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
