View source for 1hd4


==SOLUTION STRUCTURE OF THE A-SUBUNIT OF HUMAN CHORIONIC GONADOTROPIN [MODELED WITH DIANTENNARY GLYCAN AT ASN78]==
<StructureSection load='1hd4' size='340' side='right'caption='[[1hd4]], [[NMR_Ensembles_of_Models | 26 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1hd4]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HD4 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1HD4 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1dz7|1dz7]], [[1e9j|1e9j]], [[1qfw|1qfw]], [[1xul|1xul]], [[1hrp|1hrp]], [[1hcn|1hcn]]</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=1hd4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hd4 OCA], [http://pdbe.org/1hd4 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1hd4 RCSB], [http://www.ebi.ac.uk/pdbsum/1hd4 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1hd4 ProSAT]</span></td></tr>
</table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/hd/1hd4_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1hd4 ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
To gain insight into intramolecular carbohydrate-protein interactions at the molecular level, the solution structure of differently deglycosylated variants of the alpha-subunit of human chorionic gonadotropin have been studied by NMR spectroscopy. Significant differences in chemical shifts and NOE intensities were observed for amino acid residues close to the carbohydrate chain at Asn78 upon deglycosylation beyond Asn78-bound GlcNAc. As no straightforward strategy is available for the calculation of the NMR structure of intact glycoproteins, a suitable computational protocol had to be developed. To this end, the X-PLOR carbohydrate force field designed for structure refinement was extended and modified. Furthermore, a computational strategy was devised to facilitate successful protein folding in the presence of extended glycans during the simulation. The values for phi and psi dihedral angles of the glycosidic linkages of the oligosaccharide core fragments GlcNAc2(beta1-4)GlcNAc1 and Man3(beta1-4)GlcNAc2 are restricted to a limited range of the broad conformational energy minima accessible for free glycans. This demonstrates that the protein core affects the dynamic behavior of the glycan at Asn78 by steric hindrance. Reciprocally, the NMR structures indicate that the glycan at Asn78 affects the stability of the protein core. The backbone angular order parameters and displacement data of the generated conformers display especially for the beta-turn 20-23 a decreased structural order upon splitting off the glycan beyond the Asn78-bound GlcNAc. In particular, the Asn-bound GlcNAc shields the protein surface from the hydrophilic environment through interaction with predominantly hydrophobic amino acid residues located in both twisted beta-hairpins consisting of residues 10-28 and 59-84.

Effects of the N-linked glycans on the 3D structure of the free alpha-subunit of human chorionic gonadotropin.,Erbel PJ, Karimi-Nejad Y, van Kuik JA, Boelens R, Kamerling JP, Vliegenthart JF Biochemistry. 2000 May 23;39(20):6012-21. PMID:10821673<ref>PMID:10821673</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 1hd4" style="background-color:#fffaf0;"></div>

==See Also==
*[[Hormone|Hormone]]
*[[Human Follicle-Stimulating Hormone Complexed with its Receptor|Human Follicle-Stimulating Hormone Complexed with its Receptor]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Boelens, R]]
[[Category: Erbel, P J.A]]
[[Category: Kamerling, J P]]
[[Category: Karimi-Nejad, Y]]
[[Category: Kuik, J A.van]]
[[Category: Vliegenthart, J F.G]]
[[Category: Chorionic gonadotropin]]
[[Category: Glycoprotein]]
[[Category: Glycoprotein structure]]
[[Category: Hcg]]
[[Category: Xplor]]