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Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
Aliases | MOG, BTN6, BTNL11, MOGIG2, NRCLP7, myelin oligodendrocyte glycoprotein | ||||||||||||||||||||||||||||||||||||||||||||||||||
External IDs | OMIM: 159465; MGI: 97435; HomoloGene: 111009; GeneCards: MOG; OMA: MOG - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Myelin oligodendrocyte glycoprotein (MOG) is a glycoprotein believed to be important in the myelination of nerves in the central nervous system (CNS). In humans this protein is encoded by the MOG gene. [5] [6] [7] It is speculated to serve as a necessary "adhesion molecule" to provide structural integrity to the myelin sheath and is known to develop late on the oligodendrocyte. [8]
While the primary molecular function of MOG is not yet known, its likely role with the myelin sheath is either in sheath "completion and/or maintenance". [7] More specifically, MOG is speculated to be "necessary" as an "adhesion molecule" on the myelin sheath of the CNS to provide the structural integrity of the myelin sheath. [8]"
MOG's cDNA coding region in humans have been shown to be "highly homologous" [9] to rats, mice, and bovine, and hence highly conserved. This suggests "an important biological role for this protein". [7]
The gene for MOG, found on chromosome 6 p21.3-p22, [10] was first sequenced in 1995. [3] It is a transmembrane protein expressed on the surface of oligodendrocyte cell and on the outermost surface of myelin sheaths. "MOG is a quantitatively minor type I transmembrane protein, [11] and is found exclusively in the CNS. "A single Ig-domain is exposed to the extracellular space" [11] and consequently allows autoantibodies easy access. and therefore is easily accessible to autoantibodies too. [7] [11] The MOG "primary nuclear transcript … is 15,561 nucleotides in length" [7] and, for humans, it has eight exons which are "separated by seven introns". [7] The introns "contain numerous reptitive [ sic] DNA [7]" sequences, among which are "14 Alu sequences within 3 introns", [7] and have a range varying from 242 to 6484 bp.
Alternatively spliced human mRNA of the MOG gene form at least nine isoforms. [12]
The crystal structure of myelin oligodendrocyte glycoprotein was determined by x-ray diffraction at a resolution of 1.45 Angstroms, using protein from the Norway rat. This protein is 139 residues long, and is a member of the immunoglobulin superfamily. [13] The dssp secondary structure of the protein is 6% helical and 43% beta sheet: there are three short helical segments and ten beta strands. [14] The beta strands are within two antiparallel beta sheets that form an immunoglobulin-like beta-sandwich fold. [15] Several features of the protein structure suggest MOG has a role as an "adhesin in the completion and/or compaction of the myelin sheath." There is a "significant strip" of electronegative charge beginning near the N-terminus and running about half the length of the molecule. Also, MOG was shown to dimerize in solution, and the shape complementarity index is high at the dimer interface, suggesting a "biologically relevant MOG dimer." [16]
Developmentally, MOG is formed "very late on oligodendrocytes and the myelin sheath". [8]
Interest in MOG has centered on its role in demyelinating diseases. Some of them are not-inflammatory, such as adrenoleukodystrophy, vanishing white matter disease, and Rubella induced mental retardation. [17]
MOG has received much of its laboratory attention in studies dealing with MS. Several studies have shown a role for antibodies against MOG in the pathogenesis of MS, [8] [18] though most of them were written before the discovery of NMO-IgG and the NMO spectrum of diseases.
Anti-MOG status is different depending whether it is measured by ELISA or by microarray ( CBA). The proper way to identify it is by microarray, reacting patient serum with living cells, and detecting the binding IgG via a fluorescent-labeled secondary antibody. [19]
Animal models of MS, namely Experimental Autoimmune Encephalomyelitis (EAE) models, have shown that "MOG-specific EAE models (of different animal strains) display/mirror human multiple sclerosis", [8] but basically explains the part involved in the optic neuritis. [20] These models with anti-MOG antibodies have been investigated extensively and are considered the only antibodies with demyelinating capacity [8] but again, EAE pathology is closer to NMO and ADEM than to the confluent demyelination observed in MS.
Anti-MOG antibodies have been shown to behave similarly to AQP4 antibodies in animal models, [20] and are considered a biomarker against the MS diagnosis [21] [22]
Anti-MOG autoimmunity has been found to be involved in most AQP4-seronegative NMO [23] [24] and also in optic neuritis and some fulminant forms of ADEM. [25] MOG antibodies in NMOSD are variable depending on the seropositivity status. [26]
The presence of anti-MOG autoantibodies has been associated with the following conditions [27]
MOG | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
Aliases | MOG, BTN6, BTNL11, MOGIG2, NRCLP7, myelin oligodendrocyte glycoprotein | ||||||||||||||||||||||||||||||||||||||||||||||||||
External IDs | OMIM: 159465; MGI: 97435; HomoloGene: 111009; GeneCards: MOG; OMA: MOG - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Myelin oligodendrocyte glycoprotein (MOG) is a glycoprotein believed to be important in the myelination of nerves in the central nervous system (CNS). In humans this protein is encoded by the MOG gene. [5] [6] [7] It is speculated to serve as a necessary "adhesion molecule" to provide structural integrity to the myelin sheath and is known to develop late on the oligodendrocyte. [8]
While the primary molecular function of MOG is not yet known, its likely role with the myelin sheath is either in sheath "completion and/or maintenance". [7] More specifically, MOG is speculated to be "necessary" as an "adhesion molecule" on the myelin sheath of the CNS to provide the structural integrity of the myelin sheath. [8]"
MOG's cDNA coding region in humans have been shown to be "highly homologous" [9] to rats, mice, and bovine, and hence highly conserved. This suggests "an important biological role for this protein". [7]
The gene for MOG, found on chromosome 6 p21.3-p22, [10] was first sequenced in 1995. [3] It is a transmembrane protein expressed on the surface of oligodendrocyte cell and on the outermost surface of myelin sheaths. "MOG is a quantitatively minor type I transmembrane protein, [11] and is found exclusively in the CNS. "A single Ig-domain is exposed to the extracellular space" [11] and consequently allows autoantibodies easy access. and therefore is easily accessible to autoantibodies too. [7] [11] The MOG "primary nuclear transcript … is 15,561 nucleotides in length" [7] and, for humans, it has eight exons which are "separated by seven introns". [7] The introns "contain numerous reptitive [ sic] DNA [7]" sequences, among which are "14 Alu sequences within 3 introns", [7] and have a range varying from 242 to 6484 bp.
Alternatively spliced human mRNA of the MOG gene form at least nine isoforms. [12]
The crystal structure of myelin oligodendrocyte glycoprotein was determined by x-ray diffraction at a resolution of 1.45 Angstroms, using protein from the Norway rat. This protein is 139 residues long, and is a member of the immunoglobulin superfamily. [13] The dssp secondary structure of the protein is 6% helical and 43% beta sheet: there are three short helical segments and ten beta strands. [14] The beta strands are within two antiparallel beta sheets that form an immunoglobulin-like beta-sandwich fold. [15] Several features of the protein structure suggest MOG has a role as an "adhesin in the completion and/or compaction of the myelin sheath." There is a "significant strip" of electronegative charge beginning near the N-terminus and running about half the length of the molecule. Also, MOG was shown to dimerize in solution, and the shape complementarity index is high at the dimer interface, suggesting a "biologically relevant MOG dimer." [16]
Developmentally, MOG is formed "very late on oligodendrocytes and the myelin sheath". [8]
Interest in MOG has centered on its role in demyelinating diseases. Some of them are not-inflammatory, such as adrenoleukodystrophy, vanishing white matter disease, and Rubella induced mental retardation. [17]
MOG has received much of its laboratory attention in studies dealing with MS. Several studies have shown a role for antibodies against MOG in the pathogenesis of MS, [8] [18] though most of them were written before the discovery of NMO-IgG and the NMO spectrum of diseases.
Anti-MOG status is different depending whether it is measured by ELISA or by microarray ( CBA). The proper way to identify it is by microarray, reacting patient serum with living cells, and detecting the binding IgG via a fluorescent-labeled secondary antibody. [19]
Animal models of MS, namely Experimental Autoimmune Encephalomyelitis (EAE) models, have shown that "MOG-specific EAE models (of different animal strains) display/mirror human multiple sclerosis", [8] but basically explains the part involved in the optic neuritis. [20] These models with anti-MOG antibodies have been investigated extensively and are considered the only antibodies with demyelinating capacity [8] but again, EAE pathology is closer to NMO and ADEM than to the confluent demyelination observed in MS.
Anti-MOG antibodies have been shown to behave similarly to AQP4 antibodies in animal models, [20] and are considered a biomarker against the MS diagnosis [21] [22]
Anti-MOG autoimmunity has been found to be involved in most AQP4-seronegative NMO [23] [24] and also in optic neuritis and some fulminant forms of ADEM. [25] MOG antibodies in NMOSD are variable depending on the seropositivity status. [26]
The presence of anti-MOG autoantibodies has been associated with the following conditions [27]