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DMD (gene)
Dystrophin is a rod-shaped cytoplasmic protein, and a vital part of a protein complex that connects the cytoskeleton of a muscle fiber to the surrounding extracellular matrix through the cell membrane. This complex is variously known as the costamere or the dystrophin-associated protein complex (DAPC). Many muscle proteins, such as α-dystrobrevin, syncoilin, synemin, sarcoglycan, dystroglycan, and sarcospan, colocalize with dystrophin at the costamere. It has a molecular weight of 427 kDa Dystrophin is coded for by the ''DMD'' gene – the largest known human gene, covering 2.4 megabases (0.08% of the human genome) at Locus (genetics), locus X chromosome, Xp21. The primary transcript in muscle measures about 2,100 kilobases and takes 16 hours to transcribe; the Mature messenger RNA, mature mRNA measures 14.0 kilobases. The 79-exon muscle transcript codes for a protein of 3685 amino acid residues. Spontaneous or inherited mutations in the dystrophin gene can cause different form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DMD Gene Location
DMD may refer to: Science and medicine * Dimethyldioxirane, an organic molecule * Dental degree#Degrees, Doctor of Dental Medicine, an academic degree for the profession of Dentistry * Duchenne muscular dystrophy, a neurodegenerative disease * Dysmyelogenic leukodystrophy, a neurodegenerative disease * Dystrophin, a gene and protein involved in Duchenne muscular dystrophy Technology * Differential mode delay, a form of signal distortion in optical fiber * Digital Message Device, a portable terminal which an artillery forward observer could use to communicate firing instructions * Digital micromirror device, an optical semiconductor on which DLP technology is based * Digital Multilayer Disk, the fluorescent multilayer optical disc format * Direct Metal/Material Deposition, a multilayer cladding process where a precisely controlled laser beam is used to melt metal powders onto a substrate * Dot Matrix Display, an information display device * Dynamic mode decomposition, method to de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabase
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding protei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dystroglycan
Dystroglycan is a protein that in humans is encoded by the ''DAG1'' gene. Dystroglycan is one of the dystrophin-associated glycoproteins, which is encoded by a 5.5 kb transcript in ''Homo sapiens'' on chromosome 3. There are two exons that are separated by a large intron. The spliced exons code for a protein product that is finally cleaved into two non-covalently associated subunits, lpha(N-terminal) and eta(C-terminal). Function In skeletal muscle the dystroglycan complex works as a transmembrane linkage between the extracellular matrix and the cytoskeleton. lphadystroglycan is extracellular and binds to merosin lpha2 laminin in the basement membrane, while etadystroglycan is a transmembrane protein and binds to dystrophin, which is a large rod-like cytoskeletal protein, absent in Duchenne muscular dystrophy patients. Dystrophin binds to intracellular actin cables. In this way, the dystroglycan complex, which links the extracellular matrix to the intracellular actin cable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actin
Actin is a protein family, family of Globular protein, globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in myofibril, muscle fibrils. It is found in essentially all Eukaryote, eukaryotic cells, where it may be present at a concentration of over 100 micromolar, μM; its mass is roughly 42 kDa, with a diameter of 4 to 7 nm. An actin protein is the monomeric Protein subunit, subunit of two types of filaments in cells: microfilaments, one of the three major components of the cytoskeleton, and thin filaments, part of the Muscle contraction, contractile apparatus in muscle cells. It can be present as either a free monomer called G-actin (globular) or as part of a linear polymer microfilament called F-actin (filamentous), both of which are essential for such important cellular functions as the Motility, mobility and contraction of cell (biology), cells during cell division. Actin participates in many important cellular pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myofiber
A muscle cell is also known as a myocyte when referring to either a cardiac muscle cell (cardiomyocyte), or a smooth muscle cell as these are both small cells. A skeletal muscle cell is long and threadlike with many nuclei and is called a muscle fiber. Muscle cells (including myocytes and muscle fibers) develop from embryonic precursor cells called myoblasts. Myoblasts fuse to form multinucleated skeletal muscle cells known as syncytia in a process known as myogenesis. Skeletal muscle cells and cardiac muscle cells both contain myofibrils and sarcomeres and form a striated muscle tissue. Cardiac muscle cells form the cardiac muscle in the walls of the heart chambers, and have a single central nucleus. Cardiac muscle cells are joined to neighboring cells by intercalated discs, and when joined in a visible unit they are described as a ''cardiac muscle fiber''. Smooth muscle cells control involuntary movements such as the peristalsis contractions in the esophagus and stomach. Sm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myofilament
Myofilaments are the three protein filaments of myofibrils in muscle cells. The main proteins involved are myosin, actin, and titin. Myosin and actin are the ''contractile proteins'' and titin is an elastic protein. The myofilaments act together in muscle contraction, and in order of size are a thick one of mostly myosin, a thin one of mostly actin, and a very thin one of mostly titin. Types of muscle tissue are striated skeletal muscle and cardiac muscle, obliquely striated muscle (found in some invertebrates), and non-striated smooth muscle. Various arrangements of myofilaments create different muscles. Striated muscle has transverse bands of filaments. In obliquely striated muscle, the filaments are staggered. Smooth muscle has irregular arrangements of filaments. Structure There are three different types of myofilaments: thick, thin, and elastic filaments. *Thick filaments consist primarily of a type of myosin, a motor protein – myosin II. Each thick filament is approxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcolemma
The sarcolemma (''sarco'' (from ''sarx'') from Greek; flesh, and ''lemma'' from Greek; sheath) also called the myolemma, is the cell membrane surrounding a skeletal muscle fiber or a cardiomyocyte. It consists of a lipid bilayer and a thin outer coat of polysaccharide material (glycocalyx) that contacts the basement membrane. The basement membrane contains numerous thin collagen fibrils and specialized proteins such as laminin that provide a scaffold to which the muscle fiber can adhere. Through transmembrane proteins in the plasma membrane, the actin skeleton inside the cell is connected to the basement membrane and the cell's exterior. At each end of the muscle fiber, the surface layer of the sarcolemma fuses with a tendon fiber, and the tendon fibers, in turn, collect into bundles to form the muscle tendons that adhere to bones. The sarcolemma generally maintains the same function in muscle cells as the plasma membrane does in other eukaryote cells. It acts as a barrier be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duchenne Muscular Dystrophy
Duchenne muscular dystrophy (DMD) is a severe type of muscular dystrophy that primarily affects boys. Muscle weakness usually begins around the age of four, and worsens quickly. Muscle loss typically occurs first in the thighs and pelvis followed by the arms. This can result in trouble standing up. Most are unable to walk by the age of 12. Affected muscles may look larger due to increased fat content. Scoliosis is also common. Some may have intellectual disability. Females with a single copy of the defective gene may show mild symptoms. The disorder is X-linked recessive. About two thirds of cases are inherited from a person's mother, while one third of cases are due to a new mutation. It is caused by a mutation in the gene for the protein dystrophin. Dystrophin is important to maintain the muscle fiber's cell membrane. Genetic testing can often make the diagnosis at birth. Those affected also have a high level of creatine kinase in their blood. Although there is no know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscular Dystrophy
Muscular dystrophies (MD) are a genetically and clinically heterogeneous group of rare neuromuscular diseases that cause progressive weakness and breakdown of skeletal muscles over time. The disorders differ as to which muscles are primarily affected, the degree of weakness, how fast they worsen, and when symptoms begin. Some types are also associated with problems in other organs. Over 30 different disorders are classified as muscular dystrophies. Of those, Duchenne muscular dystrophy (DMD) accounts for approximately 50% of cases and affects males beginning around the age of four. Other relatively common muscular dystrophies include Becker muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy, whereas limb–girdle muscular dystrophy and congenital muscular dystrophy are themselves groups of several – usually ultrarare – genetic disorders. Muscular dystrophies are caused by mutations in genes, usually those involved in making muscle prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exon
An exon is any part of a gene that will form a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing. The term ''exon'' refers to both the DNA sequence within a gene and to the corresponding sequence in RNA transcripts. In RNA splicing, introns are removed and exons are covalently joined to one another as part of generating the mature RNA. Just as the entire set of genes for a species constitutes the genome, the entire set of exons constitutes the exome. History The term ''exon'' derives from the expressed region and was coined by American biochemist Walter Gilbert in 1978: "The notion of the cistron… must be replaced by that of a transcription unit containing regions which will be lost from the mature messengerwhich I suggest we call introns (for intragenic regions)alternating with regions which will be expressedexons." This definition was originally made for protein-coding transcripts that are spliced before being translated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mature Messenger RNA
Mature messenger RNA, often abbreviated as mature mRNA is a eukaryotic RNA transcript that has been spliced and processed and is ready for translation in the course of protein synthesis. Unlike the eukaryotic RNA immediately after transcription known as precursor messenger RNA, mature mRNA consists exclusively of exons and has all introns removed. Mature mRNA is also called "mature transcript", "mature RNA" or "mRNA". The production of a mature mRNA molecule occurs in 3 steps: # Capping of the 5' end # Polyadenylation of the 3' end # RNA Splicing of the introns Capping the 5' End During capping, a 7-methylguanosine residue is attached to the 5'-terminal end of the primary transcripts.This is otherwise known as the GTP or 5' cap. The 5' cap is used to increase mRNA stability. Further, the 5' cap is used as an attachment point for ribosomes. Beyond this, the 5' cap has also been shown to have a role in exporting the mature mRNA from the nucleus and into the cytoplasm. Pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilobase
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine– thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
