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Proteolipid Protein 1
Proteolipid protein 1 (PLP1) is a form of myelin proteolipid protein (PLP). Mutations in ''PLP1'' are associated with Pelizaeus–Merzbacher disease. It is a 4 transmembrane domain protein which is proposed to bind other copies of itself on the extracellular side of the membrane. In a myelin sheath, as the layers of myelin wraps come together, PLP will bind itself and tightly hold the cellular membranes together. This gene encodes a transmembrane proteolipid protein that is the predominant myelin protein present in the central nervous system (CNS). The encoded protein functions in myelination. This protein may play a role in the compaction, stabilization, and maintenance of myelin sheaths, as well as in oligodendrocyte development and axonal survival. Mutations associated with this gene cause X-linked Pelizaeus–Merzbacher disease and spastic paraplegia type 2. Two transcript variants encoding distinct isoforms have been identified for this gene. In melanocytic cells PLP1 gene e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelin Proteolipid Protein
Myelin proteolipid protein (PLP or lipophilin) is the major myelin protein from the central nervous system (CNS). It plays an important role in the formation or maintenance of the multilamellar structure of myelin. The myelin sheath is a multi-layered membrane, unique to the nervous system, that functions as an insulator to greatly increase the efficiency of axonal impulse conduction. In humans, point mutations in PLP are the cause of Pelizaeus–Merzbacher disease (PMD), a neurologic disorder of myelin metabolism. In animals demyelinating diseases such as mouse 'jimpy' or dog 'shaking pup' are also caused by mutations in PLP. PLP is a highly conserved hydrophobic protein of 276 to 280 amino acids which seems to contain four transmembrane segments, two disulfide bonds and which covalently binds lipids (at least six palmitate groups in mammals). PLP is highly related to GPM6A, a neuronal membrane glycoprotein Glycoproteins are proteins which contain oligosaccharide chains co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication (translesion synthesis). Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelizaeus–Merzbacher Disease
Pelizaeus– Merzbacher disease is an X-linked neurological disorder that damages oligodendrocytes in the central nervous system. It is caused by mutations in proteolipid protein 1 (''PLP1''), a major myelin protein. It is characterized by a decrease in the amount of insulating myelin surrounding the nerves (hypomyelination) and belongs to a group of genetic diseases referred to as leukodystrophies. Signs and symptoms The hallmark signs and symptoms of Pelizaeus–Merzbacher disease include little or no movement in the arms or legs, respiratory difficulties, and characteristic horizontal movements of the eyes left to right. The onset of Pelizaeus–Merzbacher disease is usually in early infancy. The most characteristic early signs are nystagmus (rapid, involuntary, rhythmic motion of the eyes) and low muscle tone. Motor abilities are delayed or never acquired, mostly depending upon the severity of the mutation. Most children with Pelizaeus–Merzbacher disease learn to underst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelin
Myelin is a lipid-rich material that surrounds nerve cell axons (the nervous system's "wires") to insulate them and increase the rate at which electrical impulses (called action potentials) are passed along the axon. The myelinated axon can be likened to an electrical wire (the axon) with insulating material (myelin) around it. However, unlike the plastic covering on an electrical wire, myelin does not form a single long sheath over the entire length of the axon. Rather, myelin sheaths the nerve in segments: in general, each axon is encased with multiple long myelinated sections with short gaps in between called nodes of Ranvier. Myelin is formed in the central nervous system (CNS; brain, spinal cord and optic nerve) by glial cells called oligodendrocytes and in the peripheral nervous system (PNS) by glial cells called Schwann cells. In the CNS, axons carry electrical signals from one nerve cell body to another. In the PNS, axons carry signals to muscles and glands or from senso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Nervous System
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric and triploblastic animals—that is, all multicellular animals except sponges and diploblasts. It is a structure composed of nervous tissue positioned along the rostral (nose end) to caudal (tail end) axis of the body and may have an enlarged section at the rostral end which is a brain. Only arthropods, cephalopods and vertebrates have a true brain (precursor structures exist in onychophorans, gastropods and lancelets). The rest of this article exclusively discusses the vertebrate central nervous system, which is radically distinct from all other animals. Overview In vertebrates, the brain and spinal cord are both enclosed in the meninges. The meninges provide a barrier to chemicals dissolv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microphthalmia-associated Transcription Factor
Microphthalmia-associated transcription factor also known as class E basic helix-loop-helix protein 32 or bHLHe32 is a protein that in humans is encoded by the ''MITF'' gene. MITF is a basic helix-loop-helix leucine zipper transcription factor involved in lineage-specific pathway regulation of many types of cells including melanocytes, osteoclasts, and mast cells. The term "lineage-specific", since it relates to MITF, means genes or traits that are only found in a certain cell type. Therefore, MITF may be involved in the rewiring of signaling cascades that are specifically required for the survival and physiological function of their normal cell precursors. MITF, together with transcription factor EB (TFEB), TFE3 and TFEC, belong to a subfamily of related bHLHZip proteins, termed the MiT-TFE family of transcription factors. The factors are able to form stable DNA-binding homo- and heterodimers. The gene that encodes for MITF resides at the ''mi'' locus in mice, and its protumor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelin Basic Protein
Myelin basic protein (MBP) is a protein believed to be important in the process of myelination of nerves in the nervous system. The myelin sheath is a multi-layered membrane, unique to the nervous system, that functions as an insulator to greatly increase the velocity of axonal impulse conduction. MBP maintains the correct structure of myelin, interacting with the lipids in the myelin membrane. MBP was initially sequenced in 1971 after isolation from bovine myelin membranes. MBP knockout mice called shiverer mice were subsequently developed and characterized in the early 1980s. ''Shiverer'' mice exhibit decreased amounts of CNS myelination and a progressive disorder characterized by tremors, seizures, and early death. The human gene for MBP is on chromosome 18; the protein localizes to the CNS and to various cells of the hematopoietic lineage. The pool of MBP in the central nervous system is very diverse, with several splice variants being expressed and a large number of pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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