3bxq

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (05:43, 17 October 2024) (edit) (undo)
 
(2 intermediate revisions not shown.)
Line 3: Line 3:
<StructureSection load='3bxq' size='340' side='right'caption='[[3bxq]], [[Resolution|resolution]] 1.30&Aring;' scene=''>
<StructureSection load='3bxq' size='340' side='right'caption='[[3bxq]], [[Resolution|resolution]] 1.30&Aring;' scene=''>
== Structural highlights ==
== Structural highlights ==
-
<table><tr><td colspan='2'>[[3bxq]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3BXQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3BXQ FirstGlance]. <br>
+
<table><tr><td colspan='2'>[[3bxq]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3BXQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3BXQ FirstGlance]. <br>
-
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
+
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.3&#8491;</td></tr>
-
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[4ins|4ins]]</div></td></tr>
+
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></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=3bxq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3bxq OCA], [https://pdbe.org/3bxq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3bxq RCSB], [https://www.ebi.ac.uk/pdbsum/3bxq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3bxq ProSAT]</span></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=3bxq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3bxq OCA], [https://pdbe.org/3bxq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3bxq RCSB], [https://www.ebi.ac.uk/pdbsum/3bxq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3bxq ProSAT]</span></td></tr>
</table>
</table>
== Disease ==
== 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>
+
[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 ==
== 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.
+
[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.
== Evolutionary Conservation ==
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
[[Image:Consurf_key_small.gif|200px|right]]
Line 17: Line 17:
<jmolCheckbox>
<jmolCheckbox>
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bx/3bxq_consurf.spt"</scriptWhenChecked>
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bx/3bxq_consurf.spt"</scriptWhenChecked>
-
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
+
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
<text>to colour the structure by Evolutionary Conservation</text>
<text>to colour the structure by Evolutionary Conservation</text>
</jmolCheckbox>
</jmolCheckbox>
Line 24: Line 24:
<div style="background-color:#fffaf0;">
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
== Publication Abstract from PubMed ==
-
Single-chain insulin (SCI) analogs provide insight into the inter-relation of hormone structure, function, and dynamics. Although compatible with wild-type structure, short connecting segments (&lt;3 residues) prevent induced fit upon receptor binding and so are essentially without biological activity. Substantial but incomplete activity can be regained with increasing linker length. Here, we describe the design, structure, and function of a single-chain insulin analog (SCI-57) containing a 6-residue linker (GGGPRR). Native receptor-binding affinity (130 +/- 8% relative to the wild type) is achieved as hindrance by the linker is offset by favorable substitutions in the insulin moiety. The thermodynamic stability of SCI-57 is markedly increased (DeltaDeltaG(u) = 0.7 +/- 0.1 kcal/mol relative to the corresponding two-chain analog and 1.9 +/- 0.1 kcal/mol relative to wild-type insulin). Analysis of inter-residue nuclear Overhauser effects demonstrates that a native-like fold is maintained in solution. Surprisingly, the glycine-rich connecting segment folds against the insulin moiety: its central Pro contacts Val(A3) at the edge of the hydrophobic core, whereas the final Arg extends the A1-A8 alpha-helix. Comparison between SCI-57 and its parent two-chain analog reveals striking enhancement of multiple native-like nuclear Overhauser effects within the tethered protein. These contacts are consistent with wild-type crystal structures but are ordinarily attenuated in NMR spectra of two-chain analogs, presumably due to conformational fluctuations. Linker-specific damping of fluctuations provides evidence for the intrinsic flexibility of an insulin monomer. In addition to their biophysical interest, ultrastable SCIs may enhance the safety and efficacy of insulin replacement therapy in the developing world.
+
The zinc insulin hexamer undergoes allosteric reorganization among three conformational states, designated T(6), T(3)R(3)(f), and R(6). Although the free monomer in solution (the active species) resembles the classical T-state, an R-like conformational change is proposed to occur upon receptor binding. Here, we distinguish between the conformational requirements of receptor binding and the crystallographic TR transition by design of an active variant refractory to such reorganization. Our strategy exploits the contrasting environments of His(B5) in wild-type structures: on the T(6) surface but within an intersubunit crevice in R-containing hexamers. The TR transition is associated with a marked reduction in His(B5) pK(a), in turn predicting that a positive charge at this site would destabilize the R-specific crevice. Remarkably, substitution of His(B5) (conserved among eutherian mammals) by Arg (occasionally observed among other vertebrates) blocks the TR transition, as probed in solution by optical spectroscopy. Similarly, crystallization of Arg(B5)-insulin in the presence of phenol (ordinarily a potent inducer of the TR transition) yields T(6) hexamers rather than R(6) as obtained in control studies of wild-type insulin. The variant structure, determined at a resolution of 1.3A, closely resembles the wild-type T(6) hexamer. Whereas Arg(B5) is exposed on the protein surface, its side chain participates in a solvent-stabilized network of contacts similar to those involving His(B5) in wild-type T-states. The substantial receptor-binding activity of Arg(B5)-insulin (40% relative to wild type) demonstrates that the function of an insulin monomer can be uncoupled from its allosteric reorganization within zinc-stabilized hexamers.
-
Design of an active ultrastable single-chain insulin analog: synthesis, structure, and therapeutic implications.,Hua QX, Nakagawa SH, Jia W, Huang K, Phillips NB, Hu SQ, Weiss MA J Biol Chem. 2008 May 23;283(21):14703-16. Epub 2008 Mar 10. PMID:18332129<ref>PMID:18332129</ref>
+
The structure of a mutant insulin uncouples receptor binding from protein allostery. An electrostatic block to the TR transition.,Wan ZL, Huang K, Hu SQ, Whittaker J, Weiss MA J Biol Chem. 2008 Jul 25;283(30):21198-210. Epub 2008 May 20. PMID:18492668<ref>PMID:18492668</ref>
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
Line 38: Line 38:
__TOC__
__TOC__
</StructureSection>
</StructureSection>
 +
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Large Structures]]
-
[[Category: Hu, S Q]]
+
[[Category: Hu SQ]]
-
[[Category: Huang, K]]
+
[[Category: Huang K]]
-
[[Category: Wan, Z L]]
+
[[Category: Wan ZL]]
-
[[Category: Weiss, M A]]
+
[[Category: Weiss MA]]
-
[[Category: Whittaker, J]]
+
[[Category: Whittaker J]]
-
[[Category: Electrostatic block]]
+
-
[[Category: Hormone]]
+
-
[[Category: Protein allostery]]
+
-
[[Category: Receptor binding]]
+
-
[[Category: Tr transition]]
+

Current revision

The structure of a mutant insulin uncouples receptor binding from protein allostery. An electrostatic block to the TR transition

PDB ID 3bxq

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools