Multiple sclerosis: Difference between revisions
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===Interferon Alpha, Interferon Beta, and Interferon Receptors 1 & 2 === | ===Interferon Alpha, Interferon Beta, and Interferon Receptors 1 & 2 === | ||
Since a PDB reference does not exist for interferon beta interacting with interferon receptors 1 or 2, and a multitude of files exist on <scene name='Multiple_sclerosis/Ifna/1'>Interferon-α</scene> interacting with the receptor, a comparison to interferon-α will be made prior to demonstrating the types of bonding that occur between the interferon and its receptor. To see more information regarding interferons, please visit the [[Interferons]] site. | Since a PDB reference does not exist for interferon beta interacting with interferon receptors 1 or 2, and a multitude of files exist on <scene name='Multiple_sclerosis/Ifna/1'>Interferon-α</scene> interacting with the receptor, a comparison to interferon-α will be made prior to demonstrating the types of bonding that occur between the interferon and its receptor. To see more information regarding interferons, please visit the [[Interferons]] site. | ||
Interferon alpha has a 31% sequence homology to interferon beta. It, too, has many <scene name='Multiple_sclerosis/Ifna_labeled/1'>identifiable regions</scene> with two <scene name='Multiple_sclerosis/Ifna_disulfide_bonds/1'>disulfide bonds</scene>: one between the <scene name='Multiple_sclerosis/Ifna_disulfide_bondsn-e/1'>N-terminus and Helix E</scene>, and the other between <scene name='Multiple_sclerosis/Ifna_disulfide_bonds_ab-g/1'>Loop AB and Helix G</scene>. It has seven <scene name='Multiple_sclerosis/Ifna_alphahelices/1'>alpha helices</scene>, as compared to the five of interferon-β, and therefore has several more <scene name='Multiple_sclerosis/Ifna_loops_regions/1'>loop regions.</scene> The helices A, C, and F run <scene name='Multiple_sclerosis/Ifna_parallelacf/2'>parallel</scene> to one another, and <scene name='Multiple_sclerosis/Ifna_antiparallel/1'>anti-parallel</scene> to B, E, and G which run <scene name='Multiple_sclerosis/Ifna_parallel_beg/2'>parallel</scene> to each other. | Interferon alpha has a 31% sequence homology to interferon beta. It, too, has many <scene name='Multiple_sclerosis/Ifna_labeled/1'>identifiable regions</scene> with two <scene name='Multiple_sclerosis/Ifna_disulfide_bonds/1'>disulfide bonds</scene>: one between the <scene name='Multiple_sclerosis/Ifna_disulfide_bondsn-e/1'>N-terminus and Helix E</scene>, and the other between <scene name='Multiple_sclerosis/Ifna_disulfide_bonds_ab-g/1'>Loop AB and Helix G</scene>. It has seven <scene name='Multiple_sclerosis/Ifna_alphahelices/1'>alpha helices</scene>, as compared to the five of interferon-β, and therefore has several more <scene name='Multiple_sclerosis/Ifna_loops_regions/1'>loop regions.</scene> The helices A, C, and F run <scene name='Multiple_sclerosis/Ifna_parallelacf/2'>parallel</scene> to one another, and <scene name='Multiple_sclerosis/Ifna_antiparallel/1'>anti-parallel</scene> to B, E, and G which run <scene name='Multiple_sclerosis/Ifna_parallel_beg/2'>parallel</scene> to each other. | ||
<scene name='Multiple_sclerosis/Ifna_notparalleltoanyoned/1'>Helix D</scene> does not run parallel or anti-parallel to either set, but rather runs at a 45-90 degree angle to them. Helix A consists of residues 10-12; Helix B of 40-43; Helix C of 53-68; Helix D of 70-75; Helix E of 78-100; Helix F of 109-132; and Helix G of 137-158. | <scene name='Multiple_sclerosis/Ifna_notparalleltoanyoned/1'>Helix D</scene> does not run parallel or anti-parallel to either set, but rather runs at a 45-90 degree angle to them. Helix A consists of residues 10-12; Helix B of 40-43; Helix C of 53-68; Helix D of 70-75; Helix E of 78-100; Helix F of 109-132; and Helix G of 137-158. | ||
Interferons -α and -β interact with a receptor at the cell surface.<ref>[http://www.jbc.org/content/282/28/20045.full?sid=cbf08059-44d4-4957-8ea7-0351cab9c2ac] Samuel, C.E. "Interferons, Interferon Receptors, Signal Transducer and Transcriptional Activators, and Inteferon Regulatory Factors." ''J Biol Chem'' 2007 282: 20045-20046. First Published on May 14, 2007, doi:10.1074/jbc.R700025200</ref> This receptor has <scene name='Multiple_sclerosis/Ifnr_domains_labeled/1'>three domains</scene>: an | Interferons -α and -β interact with a receptor at the cell surface.<ref>[http://www.jbc.org/content/282/28/20045.full?sid=cbf08059-44d4-4957-8ea7-0351cab9c2ac] Samuel, C.E. "Interferons, Interferon Receptors, Signal Transducer and Transcriptional Activators, and Inteferon Regulatory Factors." ''J Biol Chem'' 2007 282: 20045-20046. First Published on May 14, 2007, doi:10.1074/jbc.R700025200</ref> This receptor has <scene name='Multiple_sclerosis/Ifnr_domains_labeled/1'>three domains</scene>: an | ||
<scene name='Multiple_sclerosis/Ifnr_n_domain_labeled/1'>N-domain, with two disulfide bonds</scene>, a <scene name='Multiple_sclerosis/Ifnr_c_domain_labeled/1'>C-domain, with one disulfide bond</scene>, and a <scene name='Multiple_sclerosis/Ifnr_linker_region_labeled/1'>linker region</scene>. The <scene name='Multiple_sclerosis/Ifnr_termini_labeled/1'>termini regions</scene> of the receptor have no secondary structure, allowing for some serious flexibility, leading to <scene name='Multiple_sclerosis/Ifnr_clash_n-c/1'>eight clashes amongst the domains</scene>.<ref name="Interferon Receptor Structure">PMID:12842042</ref> | <scene name='Multiple_sclerosis/Ifnr_n_domain_labeled/1'>N-domain, with two disulfide bonds</scene>, a <scene name='Multiple_sclerosis/Ifnr_c_domain_labeled/1'>C-domain, with one disulfide bond</scene>, and a <scene name='Multiple_sclerosis/Ifnr_linker_region_labeled/1'>linker region</scene>. The <scene name='Multiple_sclerosis/Ifnr_termini_labeled/1'>termini regions</scene> of the receptor have no secondary structure, allowing for some serious flexibility, leading to <scene name='Multiple_sclerosis/Ifnr_clash_n-c/1'>eight clashes amongst the domains</scene>.<ref name="Interferon Receptor Structure">PMID:12842042</ref> | ||
Interferon-α <scene name='Multiple_sclerosis/Ifnawithreceptorcolored/1'>binds</scene> to an interferon receptor mainly with helices C and G. There are many <scene name='Multiple_sclerosis/Ifnawithreceptorintrxns/2'>residues</scene> within 4 angstroms of one another. These residues could form many <scene name='Multiple_sclerosis/Ifnawithreceptorintrxns/5'>different types of bonds</scene>, illustrated in white dotted lines. | Interferon-α <scene name='Multiple_sclerosis/Ifnawithreceptorcolored/1'>binds</scene> to an interferon receptor mainly with helices C and G. There are many <scene name='Multiple_sclerosis/Ifnawithreceptorintrxns/2'>residues</scene> within 4 angstroms of one another. These residues could form many <scene name='Multiple_sclerosis/Ifnawithreceptorintrxns/5'>different types of bonds</scene>, illustrated in white dotted lines. Given that interferon-α does not undergo many structural changes upon binding to interferon receptor II, Quadt-Akabayov et al. have concluded that the binding mechanism is similar to that of a lock and key. | ||
===Interferon Beta and MS=== | ===Interferon Beta and MS=== | ||