Sarcolemma: The excitable plasma membrane of a muscle cell. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)Dystrophin: A muscle protein localized in surface membranes which is the product of the Duchenne/Becker muscular dystrophy gene. Individuals with Duchenne muscular dystrophy usually lack dystrophin completely while those with Becker muscular dystrophy have dystrophin of an altered size. It shares features with other cytoskeletal proteins such as SPECTRIN and alpha-actinin but the precise function of dystrophin is not clear. One possible role might be to preserve the integrity and alignment of the plasma membrane to the myofibrils during muscle contraction and relaxation. MW 400 kDa.Muscular Dystrophy, AnimalUtrophin: An autosomally-encoded 376-kDa cytoskeletal protein that is similar in structure and function to DYSTROPHIN. It is a ubiquitously-expressed protein that plays a role in anchoring the CYTOSKELETON to the PLASMA MEMBRANE.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.Dystrophin-Associated Proteins: A group of proteins that associate with DYSTROPHIN at the CELL MEMBRANE to form the DYSTROPHIN-ASSOCIATED PROTEIN COMPLEX.Mice, Inbred mdx: A strain of mice arising from a spontaneous MUTATION (mdx) in inbred C57BL mice. This mutation is X chromosome-linked and produces viable homozygous animals that lack the muscle protein DYSTROPHIN, have high serum levels of muscle ENZYMES, and possess histological lesions similar to human MUSCULAR DYSTROPHY. The histological features, linkage, and map position of mdx make these mice a worthy animal model of DUCHENNE MUSCULAR DYSTROPHY.Dystroglycans: Dystrophin-associated proteins that play role in the formation of a transmembrane link between laminin-2 and DYSTROPHIN. Both the alpha and the beta subtypes of dystroglycan originate via POST-TRANSLATIONAL PROTEIN PROCESSING of a single precursor protein.Caveolin 3: A caveolin that is expressed exclusively in MUSCLE CELLS and is sufficient to form CAVEOLAE in SARCOLEMMA. Mutations in caveolin 3 are associated with multiple muscle diseases including DISTAL MYOPATHY and LIMB-GIRDLE MUSCULAR DYSTROPHY.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Sarcoglycans: A family of transmembrane dystrophin-associated proteins that play a role in the membrane association of the DYSTROPHIN-ASSOCIATED PROTEIN COMPLEX.Muscles: Contractile tissue that produces movement in animals.Muscular Dystrophies: A heterogeneous group of inherited MYOPATHIES, characterized by wasting and weakness of the SKELETAL MUSCLE. They are categorized by the sites of MUSCLE WEAKNESS; AGE OF ONSET; and INHERITANCE PATTERNS.Muscle Proteins: The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.Muscle Fibers, Skeletal: Large, multinucleate single cells, either cylindrical or prismatic in shape, that form the basic unit of SKELETAL MUSCLE. They consist of MYOFIBRILS enclosed within and attached to the SARCOLEMMA. They are derived from the fusion of skeletal myoblasts (MYOBLASTS, SKELETAL) into a syncytium, followed by differentiation.4-Nitrophenylphosphatase: An enzyme that catalyzes the hydrolysis of nitrophenyl phosphates to nitrophenols. At acid pH it is probably ACID PHOSPHATASE (EC 3.1.3.2); at alkaline pH it is probably ALKALINE PHOSPHATASE (EC 3.1.3.1). EC 3.1.3.41.Sodium-Potassium-Exchanging ATPase: An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.Muscular Dystrophy, Duchenne: An X-linked recessive muscle disease caused by an inability to synthesize DYSTROPHIN, which is involved with maintaining the integrity of the sarcolemma. Muscle fibers undergo a process that features degeneration and regeneration. Clinical manifestations include proximal weakness in the first few years of life, pseudohypertrophy, cardiomyopathy (see MYOCARDIAL DISEASES), and an increased incidence of impaired mentation. Becker muscular dystrophy is a closely related condition featuring a later onset of disease (usually adolescence) and a slowly progressive course. (Adams et al., Principles of Neurology, 6th ed, p1415)Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Nitric Oxide Synthase Type I: A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in NERVE TISSUE.Costameres: STRIATED MUSCLE cell components which anchor the MYOFIBRILS from the Z-bands to the SARCOLEMMA and EXTRACELLULAR MATRIX. Costameric proteins include the proteins of FOCAL ADHESIONS.Sarcoplasmic Reticulum: A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.Freeze Fracturing: Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.Shadowing (Histology): The technique of spraying a tissue specimen with a thin coat of a heavy metal such as platinum. The specimen is sprayed from an oblique angle, which results in the uneven deposition of the coating. The varying thicknesses create a shadow effect and give a three-dimensional appearance to the specimen.Sodium-Calcium Exchanger: An electrogenic ion exchange protein that maintains a steady level of calcium by removing an amount of calcium equal to that which enters the cells. It is widely distributed in most excitable membranes, including the brain and heart.Caveolins: The main structural proteins of CAVEOLAE. Several distinct genes for caveolins have been identified.Wheat Germ Agglutinins: Lectins purified from the germinating seeds of common wheat (Triticum vulgare); these bind to certain carbohydrate moieties on cell surface glycoproteins and are used to identify certain cell populations and inhibit or promote some immunological or physiological activities. There are at least two isoforms of this lectin.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Plectin: A cytoskeletal linker protein with a molecular weight of greater than 500 kDa. It binds INTERMEDIATE FILAMENTS; MICROTUBULES; and ACTIN CYTOSKELETON and plays a central role in the organization and stability of the CYTOSKELETON. Plectin is phosphorylated by CALMODULIN KINASE; PROTEIN KINASE A; and PROTEIN KINASE C.Myofibrils: The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .Myocytes, Cardiac: Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Heart Ventricles: The lower right and left chambers of the heart. The right ventricle pumps venous BLOOD into the LUNGS and the left ventricle pumps oxygenated blood into the systemic arterial circulation.Cytoskeletal Proteins: Major constituent of the cytoskeleton found in the cytoplasm of eukaryotic cells. They form a flexible framework for the cell, provide attachment points for organelles and formed bodies, and make communication between parts of the cell possible.Aquaporin 4: Aquaporin 4 is the major water-selective channel in the CENTRAL NERVOUS SYSTEM of mammals.Ligusticum: A plant genus of the family APIACEAE.Chemistry, Bioinorganic: Field of chemistry pertaining to the study of inorganic compounds or ions and their interactions with biological ligands at the molecular level.Calcium-Transporting ATPases: Cation-transporting proteins that utilize the energy of ATP hydrolysis for the transport of CALCIUM. They differ from CALCIUM CHANNELS which allow calcium to pass through a membrane without the use of energy.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Vinculin: A cytoskeletal protein associated with cell-cell and cell-matrix interactions. The amino acid sequence of human vinculin has been determined. The protein consists of 1066 amino acid residues and its gene has been assigned to chromosome 10.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Desmin: An intermediate filament protein found predominantly in smooth, skeletal, and cardiac muscle cells. Localized at the Z line. MW 50,000 to 55,000 is species dependent.Heart: The hollow, muscular organ that maintains the circulation of the blood.Myocardial Contraction: Contractile activity of the MYOCARDIUM.Muscle Contraction: A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.Glucose Transporter Type 4: A glucose transport protein found in mature MUSCLE CELLS and ADIPOCYTES. It promotes transport of glucose from the BLOOD into target TISSUES. The inactive form of the protein is localized in CYTOPLASMIC VESICLES. In response to INSULIN, it is translocated to the PLASMA MEMBRANE where it facilitates glucose uptake.Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.Muscular Diseases: Acquired, familial, and congenital disorders of SKELETAL MUSCLE and SMOOTH MUSCLE.Muscle Fibers, Fast-Twitch: Skeletal muscle fibers characterized by their expression of the Type II MYOSIN HEAVY CHAIN isoforms which have high ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment. Several fast types have been identified.Receptors, Albumin: Cell surface proteins that bind albumin with high affinity and trigger intracellular changes influencing the behavior of cells.Neuromuscular Junction: The synapse between a neuron and a muscle.Saxitoxin: A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.Spectrin: A high molecular weight (220-250 kDa) water-soluble protein which can be extracted from erythrocyte ghosts in low ionic strength buffers. The protein contains no lipids or carbohydrates, is the predominant species of peripheral erythrocyte membrane proteins, and exists as a fibrous coating on the inner, cytoplasmic surface of the membrane.Ouabain: A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.Dihydroalprenolol: Hydrogenated alprenolol derivative where the extra hydrogens are often tritiated. This radiolabeled form of ALPRENOLOL, a beta-adrenergic blocker, is used to label the beta-adrenergic receptor for isolation and study.Myotonia: Prolonged failure of muscle relaxation after contraction. This may occur after voluntary contractions, muscle percussion, or electrical stimulation of the muscle. Myotonia is a characteristic feature of MYOTONIC DISORDERS.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Nitrendipine: A calcium channel blocker with marked vasodilator action. It is an effective antihypertensive agent and differs from other calcium channel blockers in that it does not reduce glomerular filtration rate and is mildly natriuretic, rather than sodium retentive.Annexin A6: Protein of the annexin family with a probable role in exocytotic and endocytotic membrane events.Ca(2+) Mg(2+)-ATPaseCalcium-Binding Proteins: Proteins to which calcium ions are bound. They can act as transport proteins, regulator proteins, or activator proteins. They typically contain EF HAND MOTIFS.Subcellular Fractions: Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)Cocos: A plant genus of the family ARECACEAE. It is a tropical palm tree that yields a large, edible hard-shelled fruit from which oil and fiber are also obtained.Dystrophin-Associated Protein Complex: A macromolecular complex of proteins that includes DYSTROPHIN and DYSTROPHIN-ASSOCIATED PROTEINS. It plays a structural role in the linking the CYTOSKELETON to the EXTRACELLULAR MATRIX.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
  • Protein Metabolism o Proteolysis- process of breaking down proteins o Protease- enzyme that breaks down proteins o Keto acids- class of breakdown products formed from the deamination oxidative acids. (majortests.com)
  • Does not form homofilaments nor heterofilaments with other IF proteins. (genecards.org)
  • Several of the muscular dystrophies, including DMD, BMD, CMD, and most forms of LGMD, are due to defects in the genes for a complex of muscle proteins. (encyclopedia.com)
  • Two classes of proteins help form caveolae: Caveolins and Cavins. (pubmedcentralcanada.ca)
  • The induction of MyoD on day 1 denoted the beginning of muscle regeneration and was followed by the reemergence of the embryonic forms of muscle contractile proteins, which peaked at day 7 . (physiology.org)
  • While the idea of ion channels consisting of only pore-forming subunits persisted in the early days of ion channel research, it is now recognized that most ion channels function within macromolecular complexes, comprised not only of the pore-forming subunits, but also of associated auxiliary subunits, regulatory enzymes, and targeting proteins. (pubmedcentralcanada.ca)
  • Thereafter, the role of non-pore-forming Nav-β-subunits channel proteins in trafficking of sodium and also the potassium channels and their importance in normal channel distribution within the cardiomyocyte are discussed by Edokobi and Isom . (frontiersin.org)
  • The insulin and exercise signaling pathways are thought to converge at the level of the Rab GAP proteins TBC1D1 and AS160, which allow for the release of the GLUT4-containing vesicles from intracellular stores, translocation to the transverse tubules and sarcolemma, and an increase in glucose uptake. (nih.gov)
  • However, the release of Ca 2+ does not occur uniformly throughout the cytoplasm but often into a localized area before being transmitted to other regions of the cell in the form of Ca 2+ waves and oscillations to actively spread information within and between cells. (portlandpress.com)
  • Myofibrils run parallel to the myocyte and typically run for its entire length, attaching to the sarcolemma at either end. (lumenlearning.com)
  • Component of the dystrophin-associated glycoprotein complex which accumulates at the neuromuscular junction (NMJ) and at a variety of synapses in the peripheral and central nervous systems and has a structural function in stabilizing the sarcolemma. (abcam.com)
  • Activated DHPR's open, forming a channel, that allows Ca2+ to pass into the cell. (wikipedia.org)
  • The cells of the inner cell mass (embryoblast), known as human embryonic stem cells (hESCs), differentiate to form four structures: the amnion, the yolk sac, the allantois, and the embryo itself. (lumenlearning.com)
  • The first differentiation of the hESCs that form the embryo proper, is in three cell types known as the germ layers: the ectoderm , the mesoderm , and the endoderm . (lumenlearning.com)
  • A myoblast is a type of embryonic progenitor cell that differentiates to form muscle cells. (lumenlearning.com)
  • indeed, the myonuclei, which are located at the periphery of the myofiber, under the sarcolemma, are arrested in the G0 phase of the cell cycle and are unable to proliferate 1,2 . (jove.com)
  • The sarcolemma possess microdomains specialized to cell-signaling events and ion channels called caveolae. (wikidoc.org)
  • Moreover, they absorb water more effectively and faster diffusion is facilitated through the increased migration of curing brine components as a result of the disrupted cell structure and the ruptured muscle fiber sarcolemma . (media.pl)
  • LGMD2D is caused by mutations in the gene encoding α-sarcoglycan (α-SG), a dystrophin-associated glycoprotein that plays a key role in the maintenance of sarcolemma integrity in striated muscles. (nature.com)
  • The mesoderm forms the skeleton and muscles, heart and circulatory system, urinary and reproductive systems, and connective tissues inside the body. (lumenlearning.com)
  • Smooth muscle cells respond to Ins P 3 -generating (sarcolemma-acting) neurotransmitters and hormones by releasing Ca 2+ from the internal store. (portlandpress.com)
  • Here, we report that a novel form of a local Ca 2+ signaling in arterial smooth muscle is linked to the development of angiotensin II-induced hypertension. (ahajournals.org)
  • In response to muscle damage or under increased workload these cells activate, migrate into damaged sites, proliferate, and fuse with existing myofibers or with each other to form new myofibers, whereas a small portion of these cells returns into quiescence [11, (thefreelibrary.com)
  • Following an injury or disease, SCs become activated, proliferate, migrate to the damaged areas, and eventually differentiate, giving rise to newly forming myofibers 5 . (jove.com)
  • There is an extensive literature addressing the subcellular structural alterations in HF, 4 - 8 with some variability in structural and functional remodeling in differing forms of experimental and human HF. (ahajournals.org)
  • Maturation and stabilization of AChR clusters ensure proper synaptic development, which forms the basis for nerve-evoked muscle contractibility. (jneurosci.org)
  • Mutations in the human laminin α 2 ( LAMA2 ) gene result in the most common form of congenital muscular dystrophy (MDC1A). (pnas.org)
  • While it is widely-accepted that mutations in ion channel pore-forming genes underlie a number of cardiac arrhythmias, current research is now focusing on the roles of auxiliary subunits in the development of arrhythmia syndromes. (pubmedcentralcanada.ca)
  • The X-linked and dominant CNM forms result from mutations in the phosphoinositide phosphatase myotubularin ( MTM1 ) and the large GTPase dynamin 2 ( DNM2 ), respectively , . (prolekare.cz)
  • However, mutations in MTM1 have also been recognized as the underlying cause of "atypical" forms of XLMTM in newborn boys, female infants, female manifesting carriers and adult men. (gu.se)
  • o Oxidative deamination- taking an amino group off of an amino acid and form ammonia and a keto acid Oxidative deamination: take one amino acid and make it into another one and can basically break down amino acids that ultimately wind up being how to get rid of excess amino acids in the system. (majortests.com)
  • We report here on the development of a new in vitro high-throughput screening assay that allows the monitoring of the proper localization of the most prevalent mutant form of α-SG (R77C substitution). (nature.com)
  • Specifically, the divergence of single-celled life forms into organisms composed of multiple cells types with specific functions required intercellular/intracellular communication, tissue synchronicity, homeostatic measures, and movement. (pubmedcentralcanada.ca)