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Desmin Related Myopathy
Desmin is a protein that in humans is encoded by the ''DES'' gene. Desmin is a muscle-specific, type III intermediate filament that integrates the sarcolemma, Z disk, and nuclear membrane in sarcomeres and regulates sarcomere architecture. Structure Desmin is a 53.5 kD protein composed of 470 amino acids, encoded by the human ''DES'' gene located on the long arm of chromosome 2. There are three major domains to the desmin protein: a conserved alpha helix rod, a variable non alpha helix head, and a carboxy-terminal tail. Desmin, as all intermediate filaments, shows no polarity when assembled. The rod domain consists of 308 amino acids with parallel alpha helical coiled coil dimers and three linkers to disrupt it. The rod domain connects to the head domain. The head domain 84 amino acids with many arginine, serine, and aromatic residues is important in filament assembly and dimer-dimer interactions. The tail domain is responsible for the integration of filaments and inte ... [...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 residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 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 peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CRYAB
Alpha-crystallin B chain is a protein that in humans is encoded by the ''CRYAB'' gene. It is part of the small heat shock protein family and functions as molecular chaperone that primarily binds misfolded proteins to prevent protein aggregation, as well as inhibit apoptosis and contribute to intracellular architecture. Post-translational modifications decrease the ability to chaperone. Mutations in ''CRYAB'' cause different cardiomyopathies, skeletal myopathies mainly myofibrillar myopathy, and also cataracts. In addition, defects in this gene/protein have been associated with cancer and neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Structure Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystalli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urothelial Carcinoma
Transitional epithelium also known as urothelium is a type of stratified epithelium. Transitional epithelium is a type of tissue that changes shape in response to stretching (stretchable epithelium). The transitional epithelium usually appears cuboidal when relaxed and squamous when stretched. This tissue consists of multiple layers of epithelial cells which can contract and expand in order to adapt to the degree of distension needed. Transitional epithelium lines the organs of the urinary system and is known here as urothelium. The bladder for example has a need for great distension. Structure The appearance of transitional epithelium differs according to its cell layer. Cells of the basal layer are cuboidal (cube-shaped), or columnar (column-shaped), while the cells of the superficial layer vary in appearance depending on the degree of distension. These cells appear to be cuboidal with a domed apex when the organ or the tube in which they reside is not stretched. When the orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoplasm
In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. The main components of the cytoplasm are cytosol (a gel-like substance), the organelles (the cell's internal sub-structures), and various cytoplasmic inclusions. The cytoplasm is about 80% water and is usually colorless. The submicroscopic ground cell substance or cytoplasmic matrix which remains after exclusion of the cell organelles and particles is groundplasm. It is the hyaloplasm of light microscopy, a highly complex, polyphasic system in which all resolvable cytoplasmic elements are suspended, including the larger organelles such as the ribosomes, mitochondria, the plant plastids, lipid droplets, and vacuoles. Most cellular activities take place within the cytoplasm, such as many metabolic pathways including glycolysis, and proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Filament
In biology, a protein filament is a long chain of protein monomers, such as those found in hair, muscle, or in flagella. Protein filaments form together to make the cytoskeleton of the cell. They are often bundled together to provide support, strength, and rigidity to the cell. When the filaments are packed up together, they are able to form three different cellular parts. The three major classes of protein filaments that make up the cytoskeleton include: actin filaments, microtubules and intermediate filaments. Cellular types Microfilaments Compared to the other parts of the cytoskeletons, the microfilaments contain the thinnest filaments, with a diameter of approximately 7 nm. Microfilaments are part of the cytoskeleton that are composed of protein called actin. Two strands of actin intertwined together form a filamentous structure allowing for the movement of motor proteins. Microfilaments can either occur in the monomeric G-actin or filamentous F-actin. Microfilamen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmin-related Myofibrillar Myopathy
Desmin-related myofibrillar myopathy, is a subgroup of the myofibrillar myopathy diseases and is the result of a mutation in the gene that codes for desmin which prevents it from forming protein filaments, instead forming aggregates of desmin and other proteins throughout the cell. Presentation Common symptoms of the disease are weakness and atrophy in the distal muscles of the lower limbs which progresses to the hands and arms, then to the trunk, neck and face. Respiratory impairment often follows. Genetics There are three major types of inheritance for this disease: Autosomal dominant, autosomal recessive and de novo. * The most severe form is autosomal recessive and it also has the earliest onset. It usually involves all three muscle tissues and leads to cardiac and respiratory failure as well as intestinal obstruction. * Autosomal Dominant inheritance shows a later onset and slower progression. It usually involves only one or two of the muscle tissues. * De novo diseases occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmosomes
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 (DIFC), which is a network of cadherin proteins, linker proteins and intermediate filaments. The DIFCs can be broken into three regions: the extracellular core region, or desmoglea, the outer dense plaque, or ODP, and the inner dense plaque, or IDP. The extracellular core region, approximately 34 nm in length, contains desmoglein and desmocollin, which are in the cadherin famil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extracellular Matrix
In biology, the extracellular matrix (ECM), also called intercellular matrix, is a three-dimensional network consisting of extracellular macromolecules and minerals, such as collagen, enzymes, glycoproteins and hydroxyapatite that provide structural and biochemical support to surrounding cells. Because multicellularity evolved independently in different multicellular lineages, the composition of ECM varies between multicellular structures; however, cell adhesion, cell-to-cell communication and differentiation are common functions of the ECM. The animal extracellular matrix includes the interstitial matrix and the basement membrane. Interstitial matrix is present between various animal cells (i.e., in the intercellular spaces). Gels of polysaccharides and fibrous proteins fill the Interstitial fluid, interstitial space and act as a compression buffer against the stress placed on the ECM. Basement membranes are sheet-like depositions of ECM on which various epithelial cells rest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondria
A mitochondrion (; ) is an organelle found in the Cell (biology), cells of most Eukaryotes, such as animals, plants and Fungus, fungi. Mitochondria have a double lipid bilayer, membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into mitosome, other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitocho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Nucleus
The cell nucleus (pl. nuclei; from Latin or , meaning ''kernel'' or ''seed'') is a membrane-bound organelle found in eukaryotic cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have no nuclei, and a few others including osteoclasts have many. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm; and the nuclear matrix, a network within the nucleus that adds mechanical support. The cell nucleus contains nearly all of the cell's genome. Nuclear DNA is often organized into multiple chromosomes – long stands of DNA dotted with various proteins, such as histones, that protect and organize the DNA. The genes within these chromosomes are structured in such a way to promote cell function. The nucleus maintains the integrity of genes and controls the activities of the cell by regulating gene expres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myofibril
A myofibril (also known as a muscle fibril or sarcostyle) is a basic rod-like organelle of a muscle cell. Skeletal muscles are composed of long, tubular cells known as muscle fibers, and these cells contain many chains of myofibrils. Each myofibril has a diameter of 1–2 micrometres. They are created during embryonic development in a process known as myogenesis. Myofibrils are composed of long proteins including actin, myosin, and titin, and other proteins that hold them together. These proteins are organized into thick, thin, and elastic myofilaments, which repeat along the length of the myofibril in sections or units of contraction called sarcomeres. Muscles contract by sliding the thick myosin, and thin actin myofilaments along each other. Structure Each myofibril has a diameter of between 1 and 2 micrometres (μm). The filaments of myofibrils, myofilaments, consist of three types, thick, thin, and elastic filaments. *Thin filaments consist primarily of the protein acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy (HCM, or HOCM when obstructive) is a condition in which the heart becomes thickened without an obvious cause. The parts of the heart most commonly affected are the interventricular septum and the ventricles. This results in the heart being less able to pump blood effectively and also may cause electrical conduction problems. People who have HCM may have a range of symptoms. People may be asymptomatic, or may have fatigue, leg swelling, and shortness of breath. It may also result in chest pain or fainting. Symptoms may be worse when the person is dehydrated. Complications may include heart failure, an irregular heartbeat, and sudden cardiac death. HCM is most commonly inherited from a person's parents in an autosomal dominant pattern. It is often due to mutations in certain genes involved with making heart muscle proteins. Other inherited causes of left ventricular hypertrophy may include Fabry disease, Friedreich's ataxia, and certain medica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
