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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 hypomyelination and belongs to a group of genetic diseases referred to as leukodystrophies.
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Gap junction beta-1 protein (GJB1), also known as connexin 32 (Cx32) is a transmembrane protein that in humans is encoded by the GJB1 gene. Gap junction beta-1 protein is a member of the gap junction connexin family of proteins that regulates and controls the transfer of communication signals across cell membranes, primarily in the liver and peripheral nervous system.
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Acetylcholinesterase, also known as AChE or acetylhydrolase, is the primary cholinesterase in the body. It is an enzyme that catalyzes the breakdown of acetylcholine and of some other choline esters that function as neurotransmitters. AChE is found at mainly neuromuscular junctions and in chemical synapses of the cholinergic type, where its activity serves to terminate synaptic transmission. It belongs to carboxylesterase family of enzymes. It is the primary target of inhibition by organophosphorus compounds such as nerve agents and pesticides.
The EGF-like domain is an evolutionary conserved protein domain, which derives its name from the epidermal growth factor where it was first described. It comprises about 30 to 40 amino-acid residues and has been found in a large number of mostly animal proteins. Most occurrences of the EGF-like domain are found in the extracellular domain of membrane-bound proteins or in proteins known to be secreted. An exception to this is the prostaglandin-endoperoxide synthase. The EGF-like domain includes 6 cysteine residues which in the epidermal growth factor have been shown to form 3 disulfide bonds. The structures of 4-disulfide EGF-domains have been solved from the laminin and integrin proteins. The main structure of EGF-like domains is a two-stranded β-sheet followed by a loop to a short C-terminal, two-stranded β-sheet. These two β-sheets are usually denoted as the major (N-terminal) and minor (C-terminal) sheets. EGF-like domains frequently occur in numerous tandem copies in proteins: these repeats typically fold together to form a single, linear solenoid domain block as a functional unit.
Glycoprotein Ib (platelet), beta polypeptide (GP1BB) also known as CD42c, is a protein that in humans is encoded by the GP1BB gene.
Glycophorin B also known as sialoglycoprotein delta and SS-active sialoglycoprotein is a protein which in humans is encoded by the GYPB gene. GYPB has also recently been designated CD235b.
Neuronal membrane glycoprotein M6-b is a protein that in humans is encoded by the GPM6B gene.
Myelin P2 protein is a protein that in humans is encoded by the PMP2 gene. Myelin protein P2 is a constituent of peripheral nervous system (PNS) myelin, also present in small amounts in central nervous system (CNS) myelin. As a structural protein, P2 is thought to stabilize the myelin membranes, and may play a role in lipid transport in Schwann cells. Structurally, P2 belongs to the family of cytoplasmic fatty acid-binding proteins (FABPs).
A proteolipid is a protein covalently linked to lipid molecules, which can be fatty acids or sterols. The process of such a linkage is known as protein lipidation, and falls into the wider category of acylation and post-translational modification. Proteolipids are abundant in brain tissue, and are also present in many other animal and plant tissues. They are proteins covalenently bound to fatty acid chains, often granting them an interface for interacting with biological membranes. They are not to be confused with lipoproteins, a kind of spherical assembly made up of many molecules of lipids and some apolipoproteins.
References
- ↑ Dautigny A, Popot JL, Pham Dinh D (1991). "Major Myelin proteolipid: the 4-alpha-helix topology". J. Membr. Biol. 120 (3): 233–246. doi:10.1007/BF01868534. PMID 1711121. S2CID 24450880.
- ↑ Kitamura K, Sakamoto Y, Yoshimura K, Nishijima T, Uyemura K (1987). "Complete amino acid sequence of PO protein in bovine peripheral nerve myelin". J. Biol. Chem. 262 (9): 4208–4214. PMID 2435734.
- ↑ Stoffel W, Schliess F (1991). "Evolution of the myelin integral membrane proteins of the central nervous system". Biol. Chem. Hoppe-Seyler. 372 (9): 865–874. doi:10.1515/bchm3.1991.372.2.865. PMID 1722981.
- ↑ Weimbs T, Sto ffel W (1992). "Proteolipid protein (PLP) of CNS myelin: positions of free, disulfide-bonded, and fatty acid thioester-linked cysteine residues and implications for the membrane topology of PLP". Biochemistry. 31 (49): 12289–12296. doi:10.1021/bi00164a002. PMID 1281423.
- ↑ Yan Y, Lagenaur C, Narayanan V (1993). "Molecular cloning of M6: identification of a PLP/DM20 gene family". Neuron. 11 (3): 423–431. doi:10.1016/0896-6273(93)90147-J. PMID 8398137. S2CID 46719251.