2k91
From Proteopedia
(Difference between revisions)
| (7 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | [[Image:2k91.png|left|200px]] | ||
| - | + | ==Enhancing the activity of insulin by stereospecific unfolding== | |
| + | <StructureSection load='2k91' size='340' side='right'caption='[[2k91]]' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[2k91]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2K91 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2K91 FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 20 models</td></tr> | ||
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2k91 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2k91 OCA], [https://pdbe.org/2k91 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2k91 RCSB], [https://www.ebi.ac.uk/pdbsum/2k91 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2k91 ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Disease == | ||
| + | [https://www.uniprot.org/uniprot/INS_HUMAN INS_HUMAN] Defects in INS are the cause of familial hyperproinsulinemia (FHPRI) [MIM:[https://omim.org/entry/176730 176730].<ref>PMID:3470784</ref> <ref>PMID:2196279</ref> <ref>PMID:4019786</ref> <ref>PMID:1601997</ref> Defects in INS are a cause of diabetes mellitus insulin-dependent type 2 (IDDM2) [MIM:[https://omim.org/entry/125852 125852]. IDDM2 is a multifactorial disorder of glucose homeostasis that is characterized by susceptibility to ketoacidosis in the absence of insulin therapy. Clinical fetaures are polydipsia, polyphagia and polyuria which result from hyperglycemia-induced osmotic diuresis and secondary thirst. These derangements result in long-term complications that affect the eyes, kidneys, nerves, and blood vessels.<ref>PMID:18192540</ref> Defects in INS are a cause of diabetes mellitus permanent neonatal (PNDM) [MIM:[https://omim.org/entry/606176 606176]. PNDM is a rare form of diabetes distinct from childhood-onset autoimmune diabetes mellitus type 1. It is characterized by insulin-requiring hyperglycemia that is diagnosed within the first months of life. Permanent neonatal diabetes requires lifelong therapy.<ref>PMID:17855560</ref> <ref>PMID:18162506</ref> Defects in INS are a cause of maturity-onset diabetes of the young type 10 (MODY10) [MIM:[https://omim.org/entry/613370 613370]. MODY10 is a form of diabetes that is characterized by an autosomal dominant mode of inheritance, onset in childhood or early adulthood (usually before 25 years of age), a primary defect in insulin secretion and frequent insulin-independence at the beginning of the disease.<ref>PMID:18192540</ref> <ref>PMID:18162506</ref> <ref>PMID:20226046</ref> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/INS_HUMAN INS_HUMAN] Insulin decreases blood glucose concentration. It increases cell permeability to monosaccharides, amino acids and fatty acids. It accelerates glycolysis, the pentose phosphate cycle, and glycogen synthesis in liver. | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | A central tenet of molecular biology holds that the function of a protein is mediated by its structure. An inactive ground-state conformation may nonetheless be enjoined by the interplay of competing biological constraints. A model is provided by insulin, well characterized at atomic resolution by x-ray crystallography. Here, we demonstrate that the activity of the hormone is enhanced by stereospecific unfolding of a conserved structural element. A bifunctional beta-strand mediates both self-assembly (within beta-cell storage vesicles) and receptor binding (in the bloodstream). This strand is anchored by an invariant side chain (Phe(B24)); its substitution by Ala leads to an unstable but native-like analog of low activity. Substitution by d-Ala is equally destabilizing, and yet the protein diastereomer exhibits enhanced activity with segmental unfolding of the beta-strand. Corresponding photoactivable derivatives (containing l- or d-para-azido-Phe) cross-link to the insulin receptor with higher d-specific efficiency. Aberrant exposure of hydrophobic surfaces in the analogs is associated with accelerated fibrillation, a form of aggregation-coupled misfolding associated with cellular toxicity. Conservation of Phe(B24), enforced by its dual role in native self-assembly and induced fit, thus highlights the implicit role of misfolding as an evolutionary constraint. Whereas classical crystal structures of insulin depict its storage form, signaling requires engagement of a detachable arm at an extended receptor interface. Because this active conformation resembles an amyloidogenic intermediate, we envisage that induced fit and self-assembly represent complementary molecular adaptations to potential proteotoxicity. The cryptic threat of misfolding poses a universal constraint in the evolution of polypeptide sequences. | ||
| - | + | Enhancing the activity of a protein by stereospecific unfolding: conformational life cycle of insulin and its evolutionary origins.,Hua QX, Xu B, Huang K, Hu SQ, Nakagawa S, Jia W, Wang S, Whittaker J, Katsoyannis PG, Weiss MA J Biol Chem. 2009 May 22;284(21):14586-96. Epub 2009 Mar 25. PMID:19321436<ref>PMID:19321436</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 2k91" style="background-color:#fffaf0;"></div> | |
| - | + | ||
==See Also== | ==See Also== | ||
| - | *[[ | + | *[[Insulin 3D Structures|Insulin 3D Structures]] |
| - | + | == References == | |
| - | == | + | <references/> |
| - | < | + | __TOC__ |
| + | </StructureSection> | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
| - | [[Category: Hu | + | [[Category: Large Structures]] |
| - | [[Category: Hua | + | [[Category: Hu SQ]] |
| - | [[Category: Huang | + | [[Category: Hua QX]] |
| - | [[Category: Jia | + | [[Category: Huang K]] |
| - | [[Category: Katsoyannis | + | [[Category: Jia WH]] |
| - | [[Category: Nakarawa | + | [[Category: Katsoyannis PG]] |
| - | [[Category: Philips | + | [[Category: Nakarawa S]] |
| - | [[Category: Weiss | + | [[Category: Philips NFP]] |
| - | [[Category: Wittaker | + | [[Category: Weiss MA]] |
| - | [[Category: Wittaker | + | [[Category: Wittaker J]] |
| - | [[Category: Xu | + | [[Category: Wittaker L]] |
| - | + | [[Category: Xu B]] | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
Current revision
Enhancing the activity of insulin by stereospecific unfolding
| |||||||||||
Categories: Homo sapiens | Large Structures | Hu SQ | Hua QX | Huang K | Jia WH | Katsoyannis PG | Nakarawa S | Philips NFP | Weiss MA | Wittaker J | Wittaker L | Xu B
