View source for 6ck2


==Insulin analog containing a YB26W mutation==
<StructureSection load='6ck2' size='340' side='right' caption='[[6ck2]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ck2]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CK2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6CK2 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=IPH:PHENOL'>IPH</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=ORN:L-ORNITHINE'>ORN</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ck2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ck2 OCA], [http://pdbe.org/6ck2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ck2 RCSB], [http://www.ebi.ac.uk/pdbsum/6ck2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ck2 ProSAT]</span></td></tr>
</table>
== Disease ==
[[http://www.uniprot.org/uniprot/INS_HUMAN INS_HUMAN]] Defects in INS are the cause of familial hyperproinsulinemia (FHPRI) [MIM:[http://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:[http://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:[http://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:[http://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 ==
[[http://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. 
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== Publication Abstract from PubMed ==
Key contributions to protein structure and stability are provided by weakly polar interactions, which arise from asymmetric electronic distributions within amino acids and peptide bonds. Of particular interest are aromatic side chains whose directional pi systems commonly stabilize protein interiors and interfaces. Here, we consider aromatic-aromatic interactions within a model protein assembly: the dimer interface of insulin. Semi-classical simulations of aromatic-aromatic interactions at this interface suggested that substitution of residue Tyr(B26) by Trp would preserve native structure while enhancing dimerization (and hence hexamer stability). The crystal structure of a Trp(B26)-insulin analog (determined as a T3R(f)3 zinc hexamer at a resolution of 2.25 A) was observed to be essentially identical to that of wild-type insulin. Remarkably and yet in general accordance with theoretical expectations, spectroscopic studies demonstrated a 150-fold increase in the in vitro lifetime of the variant hexamer, a key pharmacokinetic parameter influencing design of long-acting formulations. Functional studies in diabetic rats indeed revealed prolonged action following subcutaneous injection. The potency of the Trp(B26)-modified analog was equal to or greater than an unmodified control. Thus exploiting a general quantum-chemical feature of protein structure and stability, our results exemplify a mechanism-based approach to the optimization of a therapeutic protein assembly.

Structure-Based Stabilization of Insulin as a Therapeutic Protein Assembly via Enhanced Aromatic-Aromatic Interactions.,Rege NK, Wickramasinghe NP, Tustan AN, Phillips NFB, Yee VC, Ismail-Beigi F, Weiss MA J Biol Chem. 2018 Jun 7. pii: RA118.003650. doi: 10.1074/jbc.RA118.003650. PMID:29880646<ref>PMID:29880646</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 6ck2" style="background-color:#fffaf0;"></div>

==See Also==
*[[Molecular Playground/Insulin|Molecular Playground/Insulin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Rege, N K]]
[[Category: Weiss, M A]]
[[Category: Yee, V C]]
[[Category: Basal]]
[[Category: Biomolecular engineering]]
[[Category: Diabetes]]
[[Category: Hormone]]
[[Category: Long-acting]]
[[Category: Peptide hormone]]
[[Category: Therapeutic]]