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Desmoglein-2
Desmoglein-2 is a protein that in humans is encoded by the ''DSG2'' gene. Desmoglein-2 is highly expressed in epithelial cells and cardiomyocytes. Desmoglein-2 is localized to desmosome structures at regions of cell-cell contact and functions to structurally adhere adjacent cells together. In cardiac muscle, these regions are specialized regions known as intercalated discs. Mutations in desmoglein-2 have been associated with arrhythmogenic right ventricular cardiomyopathy and familial dilated cardiomyopathy. Structure Desmoglein-2 is a 122.2 kDa protein composed of 1118 amino acids. Desmoglein-2 is a calcium-binding transmembrane glycoprotein component of desmosomes in vertebrate cells. Currently, four desmoglein subfamily members have been identified and all are members of the cadherin cell adhesion molecule superfamily. These desmoglein gene family members are located in a cluster on chromosome 18. This second family member, desmoglein-2 is expressed in desmosome-containing tis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmosome
A desmosome (; "binding body"), also known as a macula adherens (plural: maculae adherentes) (Latin for ''adhering spot''), is a cell structure specialized for cell-to-cell adhesion. A type of junctional complex, they are localized spot-like adhesions randomly arranged on the lateral sides of plasma membranes. Desmosomes are one of the stronger cell-to-cell adhesion types and are found in tissue that experience intense mechanical stress, such as cardiac muscle tissue, bladder tissue, gastrointestinal mucosa, and epithelia. Structure Desmosomes are composed of desmosome-intermediate filament complexes (DIFCs), a network of cadherin proteins, linker proteins and intermediate filaments. The DIFCs can be broken into three regions: the extracellular core region ("desmoglea"), the outer dense plaque (ODP), and the inner dense plaque (IDP). The extracellular core region, approximately 34 nm in length, contains desmoglein and desmocollin, which are in the cadherin family of cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arrhythmogenic Right Ventricular Cardiomyopathy
Arrhythmogenic cardiomyopathy (ACM) is an inherited heart disease. ACM is caused by genetic defects of parts of the cardiac muscle known as desmosomes, areas on the surface of muscle cells which link them together. The desmosomes are composed of several proteins, and many of those proteins can have harmful mutations. ARVC can also develop in intense endurance training, endurance athletes in the absence of desmosomal abnormalities. Exercise-induced ARVC is possibly a result of excessive right ventricular wall stress during high intensity exercise. The disease is a type of Ischemia, non-ischemic cardiomyopathy that primarily involves the Ventricle (heart), right ventricle, though cases of exclusive left ventricular disease have been reported. It is characterized by hypokinesia, hypokinetic areas involving the free wall of the ventricle, with fibrofatty replacement of the myocardium, with associated Heart arrhythmia, arrhythmias often originating in the right ventricle. The nomenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plakoglobin
Plakoglobin, also known as junction plakoglobin or gamma-catenin, is a protein that in humans is encoded by the ''JUP'' gene. Plakoglobin is a member of the catenin protein family and homologous to β-catenin. Plakoglobin is a cytoplasmic component of desmosomes and adherens junctions structures located within intercalated discs of cardiac muscle that function to anchor sarcomeres and join adjacent cells in cardiac muscle. Mutations in plakoglobin are associated with arrhythmogenic right ventricular dysplasia. Structure Human plakoglobin is 81.7 kDa in molecular weight and 745 amino acids long. The ''JUP'' gene contains 13 exons spanning 17 kb on chromosome 17q21. Plakoglobin is a member of the catenin family, since it contains a distinct repeating amino acid motif called the armadillo repeat. Plakoglobin is highly similar to β-catenin; both have 12 armadillo repeats as well as N-terminal and C-terminal globular domains of unknown structure. Plakoglobin was originally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adherens Junctions
In cell biology, adherens junctions (or zonula adherens, intermediate junction, or "belt desmosome") are protein complexes that occur at cell–cell junctions and cell–matrix junctions in epithelial and endothelial tissues, usually more basal than tight junctions. An adherens junction is defined as a cell junction whose cytoplasmic face is linked to the actin cytoskeleton. They can appear as bands encircling the cell (zonula adherens) or as spots of attachment to the extracellular matrix (focal adhesion). Adherens junctions uniquely disassemble in uterine epithelial cells to allow the blastocyst to penetrate between epithelial cells. A similar cell junction in non-epithelial, non-endothelial cells is the fascia adherens. It is structurally the same, but appears in ribbonlike patterns that do not completely encircle the cells. One example is in cardiomyocytes. Proteins Adherens junctions are composed of the following proteins: * cadherins. The cadherins are a family o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the proteinogenic amino acids. Only the L- stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, '' sericum''. Serine's structure was established in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asparagine
Asparagine (symbol Asn or N) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain carboxamide, classifying it as a polar (at physiological pH), aliphatic amino acid. It is non-essential in humans, meaning the body can synthesize it. It is encoded by the codons AAU and AAC. The one-letter symbol N for asparagine was assigned arbitrarily, with the proposed mnemonic asparagi''N''e; History Asparagine was first isolated in 1806 in a crystalline form by French chemists Louis Nicolas Vauquelin and Pierre Jean Robiquet (then a young assistant). It was isolated from asparagus juice, in which it is abundant, hence the chosen name. It was the first amino acid to be isolated. Three years later, in 1809, Pierre Jean Robiquet identified a substance from l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart Arrhythmia
Arrhythmias, also known as cardiac arrhythmias, are irregularities in the cardiac cycle, heartbeat, including when it is too fast or too slow. Essentially, this is anything but normal sinus rhythm. A resting heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a resting heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be presyncope, lightheadedness, Syncope (medicine), passing out, shortness of breath, chest pain, or decreased level of consciousness. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in cardiac arrest, sudden death. Arrhythmias are often categorized into four groups: premature heart beat, extra beats, supraventricular tachycard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibrosis
Fibrosis, also known as fibrotic scarring, is the development of fibrous connective tissue in response to an injury. Fibrosis can be a normal connective tissue deposition or excessive tissue deposition caused by a disease. Repeated injuries, chronic inflammation and repair are susceptible to fibrosis, where an accidental excessive accumulation of extracellular matrix components, such as the collagen, is produced by fibroblasts, leading to the formation of a permanent fibrotic scar. In response to injury, this is called scarring, and if fibrosis arises from a single cell line, this is called a fibroma. Physiologically, fibrosis acts to deposit connective tissue, which can interfere with or totally inhibit the normal architecture and function of the underlying organ or tissue. Fibrosis can be used to describe the pathological state of excess deposition of fibrous tissue, as well as the process of connective tissue deposition in healing. Defined by the pathological accumulation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Left Ventricle
A ventricle is one of two large chambers located toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the upper heart that is smaller than a ventricle. Interventricular means between the ventricles (for example the interventricular septum), while intraventricular means within one ventricle (for example an intraventricular block). In a four-chambered heart, such as that in humans, there are two ventricles that operate in a double circulatory system: the right ventricle pumps blood into the pulmonary circulation to the lungs, and the left ventricle pumps blood into the systemic circulation through the aorta. Structure Ventricles have thicker walls than atria and generate higher blood pressures. The physiological load on the ventricles requiring pumping of blood throughout the body and lungs is much greater than the pressure generated by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammation
Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', ''dolor'', ''rubor'', ''tumor'', and ''functio laesa''). Inflammation is a generic response, and therefore is considered a mechanism of innate immunity, whereas adaptive immunity is specific to each pathogen. Inflammation is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out damaged cells and tissues, and initiate tissue repair. Too little inflammation could lead to progressive tissue destruction by the harmful stimulus (e.g. bacteria) and compromise the survival of the organism. However inflammation can also have negative effects. Too much inflammation, in the form of chronic inflammation, is associated with variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine disrupts the formation of alpha-helices in secondary protein structure. Its small side chain causes it to favor random coils instead. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a '' Clostridium tetani'' infection) can cause spastic paralysis due to uninhibited muscle contraction. It is the only achiral proteinogenic amino acid. It can fit into both hydrophilic and hydrophobic environments, due to its minimal side chain of only one hydrogen atom. History and etymology Glycine was discovered in 1820 by French chemist Henri Braconnot when he hydrolyzed gelatin by boiling it with sulfuric acid. He originally called it "sugar of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
