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Glycine—tRNA Ligase
Glycine—tRNA ligase also known as glycyl–tRNA synthetase is an enzyme that in humans is encoded by the ''GARS1'' gene. Function This gene encodes glycyl-tRNA synthetase, one of the aminoacyl-tRNA synthetases that charge tRNAs with their cognate amino acids. The encoded enzyme is an (alpha)2 dimer which belongs to the class II family of tRNA synthetases. Reaction In enzymology, a glycine—tRNA ligase () is an enzyme that catalyzes the chemical reaction :ATP + glycine + tRNAGly \rightleftharpoons AMP + diphosphate + glycyl-tRNAGly The 3 substrates of this enzyme are ATP, glycine, and tRNA(Gly), whereas its 3 products are AMP, diphosphate, and glycyl-tRNA(Gly). This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. The systematic name of this enzyme class is glycine:tRNAGly ligase (AMP-forming). Other names in common use include glycyl-tRNA synthetase, glycyl-transfer ribonucleate synt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuromuscular Junction
A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. Muscles require innervation to function—and even just to maintain muscle tone, avoiding atrophy. In the neuromuscular system nerves from the central nervous system and the peripheral nervous system are linked and work together with muscles. Synaptic transmission at the neuromuscular junction begins when an action potential reaches the presynaptic terminal of a motor neuron, which activates voltage-gated calcium channels to allow calcium ions to enter the neuron. Calcium ions bind to sensor proteins (synaptotagmins) on synaptic vesicles, triggering vesicle fusion with the cell membrane and subsequent neurotransmitter release from the motor neuron into the synaptic cleft. In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axon
An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action potentials away from the nerve cell body. The function of the axon is to transmit information to different neurons, muscles, and glands. In certain sensory neurons (pseudounipolar neurons), such as those for touch and warmth, the axons are called afferent nerve fibers and the electrical impulse travels along these from the periphery to the cell body and from the cell body to the spinal cord along another branch of the same axon. Axon dysfunction can be the cause of many inherited and acquired neurological disorders that affect both the peripheral and central neurons. Nerve fibers are classed into three typesgroup A nerve fibers, group B nerve fibers, and group C nerve fibers. Groups A and B are myelinated, and group C are unmyelinated. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatomyositis
Dermatomyositis (DM) is a long-term inflammatory disorder which affects skin and the muscles. Its symptoms are generally a skin rash and worsening muscle weakness over time. These may occur suddenly or develop over months. Other symptoms may include weight loss, fever, lung inflammation, or light sensitivity. Complications may include calcium deposits in muscles or skin. The cause is unknown. Theories include that it is an autoimmune disease or a result of a viral infection. Dermatomyositis may develop as a paraneoplastic syndrome associated with several forms of malignancy. It is a type of inflammatory myopathy. Diagnosis is typically based on some combination of symptoms, blood tests, electromyography, and muscle biopsies. While no cure for the condition is known, treatments generally improve symptoms. Treatments may include medication, physical therapy, exercise, heat therapy, orthotics and assistive devices, and rest. Medications in the corticosteroids family are typic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymyositis
Polymyositis (PM) is a type of chronic inflammation of the muscles (inflammatory myopathy) related to dermatomyositis and inclusion body myositis. Its name means "inflammation of many muscles" ('' poly-'' + '' myos-'' + ''-itis''). The inflammation of polymyositis is mainly found in the endomysial layer of skeletal muscle, whereas dermatomyositis is characterized primarily by inflammation of the perimysial layer of skeletal muscles. Signs and symptoms The hallmark of polymyositis is weakness and/or loss of muscle mass in the proximal musculature, as well as flexion of the neck and torso. These symptoms can be associated with marked pain in these areas as well. The hip extensors are often severely affected, leading to particular difficulty in climbing stairs and rising from a seated position. The skin involvement of dermatomyositis is absent in polymyositis. Dysphagia (difficulty swallowing) or other problems with esophageal motility occur in as many as 1/3 of patients. Low grad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trk Receptor
Trk receptors are a family of tyrosine kinases that regulates synaptic strength and plasticity in the mammalian nervous system. Trk receptors affect neuronal survival and differentiation through several signaling cascades. However, the activation of these receptors also has significant effects on functional properties of neurons. The common ligands of trk receptors are neurotrophins, a family of growth factors critical to the functioning of the nervous system. The binding of these molecules is highly specific. Each type of neurotrophin has different binding affinity toward its corresponding Trk receptor. The activation of Trk receptors by neurotrophin binding may lead to activation of signal cascades resulting in promoting survival and other functional regulation of cells. Origin of the name ''trk'' The abbreviation ''trk'' (often pronounced 'track') stands for tropomyosin receptor kinase or ''tyrosine'' receptor kinase (and not "''tyrosine'' kinase receptor" nor "tropomyosi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuropilin 1
Neuropilin-1 is a protein that in humans is encoded by the ''NRP1'' gene. In humans, the neuropilin 1 gene is located at 10p11.22. This is one of two human neuropilins. Function NRP1 is a membrane-bound coreceptor to a tyrosine kinase receptor for both vascular endothelial growth factor (for example, VEGFA) and semaphorin (for example, SEMA3A) family members. NRP1 plays versatile roles in angiogenesis, axon guidance, cell survival, migration, and invasion. upplied by OMIMref name="entrez"/> Interactions Neuropilin 1 has been shown to interact with Vascular endothelial growth factor A. Role in COVID-19 Research has shown that neuropilin 1 facilitates entry of SARS-CoV-2 into cells, making it a possible target for future antiviral drugs. Implication in cancer Neuropilin 1 has been implicated in the vascularization and progression of cancers. NRP1 expression has been shown to be elevated in a number of human patient tumor samples, including brain, prostate, breast, col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peripheral Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon, within the nerve, is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. Finally, the entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EEF1D
Elongation factor 1-delta is a protein that in humans is encoded by the ''EEF1D'' gene. Function This gene encodes a subunit of the elongation factor-1 complex, which is responsible for the enzymatic delivery of aminoacyl tRNAs to the ribosome. This subunit functions as guanine nucleotide exchange factor. It is reported that this subunit interacts with HIV-1 Tat, and thus it represses the translation of host-cell, but not HIV-1, mRNAs. Several alternatively spliced transcript variants have been found for this gene, however, the full length nature of only two variants has been determined. Interactions EEF1D has been shown to interact with Glycyl-tRNA synthetase, EEF1G and KTN1, and is predicted to interact with TMEM63A Transmembrane protein 63A is a protein that in humans is encoded by the ''TMEM63A'' gene. The mature human protein is approximately 92.1 kilodaltons (kDa), with a relatively high conservation of mass in orthologs. The protein contains eleven tran .... Ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
