This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


1olm

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (09:01, 9 May 2024) (edit) (undo)
 
(16 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:1olm.jpg|left|200px]]<br /><applet load="1olm" size="450" color="white" frame="true" align="right" spinBox="true"
 
-
caption="1olm, resolution 1.95&Aring;" />
 
-
'''SUPERNATANT PROTEIN FACTOR IN COMPLEX WITH RRR-ALPHA-TOCOPHERYLQUINONE: A LINK BETWEEN OXIDIZED VITAMIN E AND CHOLESTEROL BIOSYNTHESIS'''<br />
 
-
==Overview==
+
==Supernatant Protein Factor in Complex with RRR-alpha-Tocopherylquinone: A Link between Oxidized Vitamin E and Cholesterol Biosynthesis==
-
The vast majority of monomeric lipid transport in nature is performed by, lipid-specific protein carriers. This class of proteins can enclose, cognate lipid molecules in a hydrophobic cavity and transport them across, the aqueous environment. Supernatant protein factor (SPF) is an enigmatic, representative of monomeric lipid transporters belonging to the SEC14, family. SPF stimulates squalene epoxidation, a downstream step of the, cholesterol biosynthetic pathway, by an unknown mechanism. Here, we, present the three-dimensional crystal structure of human SPF in complex, with RRR-alpha-tocopherylquinone, the major physiological oxidation, product of RRR-alpha-tocopherol, at a resolution of 1.95A. The structure, of the complex reveals how SPF sequesters RRR-alpha-tocopherylquinone, (RRR-alpha-TQ) in its protein body and permits a comparison with the, recently solved structure of human alpha-tocopherol transfer protein, (alpha-TTP) in complex with RRR-alpha-tocopherol. Recent findings have, shown that RRR-alpha-TQ is reduced in vivo to RRR-alpha-TQH(2), the latter, has been suggested to protect low-density lipoprotein (LDL) particles from, oxidation. Hence, the antioxidant function of the redox couple, RRR-alpha-TQ/RRR-alpha-TQH(2) in blocking LDL oxidation may reduce, cellular cholesterol uptake and thus explain how SPF upregulates, cholesterol synthesis.
+
<StructureSection load='1olm' size='340' side='right'caption='[[1olm]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
 +
== Structural highlights ==
 +
<table><tr><td colspan='2'>[[1olm]] is a 3 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=1OLM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1OLM FirstGlance]. <br>
 +
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.95&#8491;</td></tr>
 +
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=VTQ:RRR-ALPHA-TOCOPHERYLQUINONE'>VTQ</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=1olm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1olm OCA], [https://pdbe.org/1olm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1olm RCSB], [https://www.ebi.ac.uk/pdbsum/1olm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1olm ProSAT]</span></td></tr>
 +
</table>
 +
== Function ==
 +
[https://www.uniprot.org/uniprot/S14L2_HUMAN S14L2_HUMAN] Carrier protein. Binds to some hydrophobic molecules and promotes their transfer between the different cellular sites. Binds with high affinity to alpha-tocopherol. Also binds with a weaker affinity to other tocopherols and to tocotrienols. May have a transcriptional activatory activity via its association with alpha-tocopherol. Probably recognizes and binds some squalene structure, suggesting that it may regulate cholesterol biosynthesis by increasing the transfer of squalene to a metabolic active pool in the cell.
 +
== 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/ol/1olm_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=1olm ConSurf].
 +
<div style="clear:both"></div>
 +
<div style="background-color:#fffaf0;">
 +
== Publication Abstract from PubMed ==
 +
The vast majority of monomeric lipid transport in nature is performed by lipid-specific protein carriers. This class of proteins can enclose cognate lipid molecules in a hydrophobic cavity and transport them across the aqueous environment. Supernatant protein factor (SPF) is an enigmatic representative of monomeric lipid transporters belonging to the SEC14 family. SPF stimulates squalene epoxidation, a downstream step of the cholesterol biosynthetic pathway, by an unknown mechanism. Here, we present the three-dimensional crystal structure of human SPF in complex with RRR-alpha-tocopherylquinone, the major physiological oxidation product of RRR-alpha-tocopherol, at a resolution of 1.95A. The structure of the complex reveals how SPF sequesters RRR-alpha-tocopherylquinone (RRR-alpha-TQ) in its protein body and permits a comparison with the recently solved structure of human alpha-tocopherol transfer protein (alpha-TTP) in complex with RRR-alpha-tocopherol. Recent findings have shown that RRR-alpha-TQ is reduced in vivo to RRR-alpha-TQH(2), the latter has been suggested to protect low-density lipoprotein (LDL) particles from oxidation. Hence, the antioxidant function of the redox couple RRR-alpha-TQ/RRR-alpha-TQH(2) in blocking LDL oxidation may reduce cellular cholesterol uptake and thus explain how SPF upregulates cholesterol synthesis.
-
==About this Structure==
+
Supernatant protein factor in complex with RRR-alpha-tocopherylquinone: a link between oxidized Vitamin E and cholesterol biosynthesis.,Stocker A, Baumann U J Mol Biol. 2003 Sep 26;332(4):759-65. PMID:12972248<ref>PMID:12972248</ref>
-
1OLM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with VTQ as [http://en.wikipedia.org/wiki/ligand ligand]. Known structural/functional Site: <scene name='pdbsite=AC1:Vtq Binding Site For Chain E'>AC1</scene>. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1OLM OCA].
+
-
==Reference==
+
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
-
Supernatant protein factor in complex with RRR-alpha-tocopherylquinone: a link between oxidized Vitamin E and cholesterol biosynthesis., Stocker A, Baumann U, J Mol Biol. 2003 Sep 26;332(4):759-65. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=12972248 12972248]
+
</div>
 +
<div class="pdbe-citations 1olm" style="background-color:#fffaf0;"></div>
 +
== References ==
 +
<references/>
 +
__TOC__
 +
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Homo sapiens]]
-
[[Category: Protein complex]]
+
[[Category: Large Structures]]
-
[[Category: Baumann, U.]]
+
[[Category: Baumann U]]
-
[[Category: Stocker, A.]]
+
[[Category: Stocker A]]
-
[[Category: VTQ]]
+
-
[[Category: activator]]
+
-
[[Category: cholesterol biosynthesis]]
+
-
[[Category: lipid-binding]]
+
-
[[Category: oxidized vitamin e]]
+
-
[[Category: transcription regulation]]
+
-
[[Category: transport]]
+
-
 
+
-
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Dec 18 17:49:30 2007''
+

Current revision

Supernatant Protein Factor in Complex with RRR-alpha-Tocopherylquinone: A Link between Oxidized Vitamin E and Cholesterol Biosynthesis

PDB ID 1olm

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools