2ou1

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|ACTIVITY=
|ACTIVITY=
|GENE=
|GENE=
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|DOMAIN=
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|RELATEDENTRY=[[1l6l|1L6L]]
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|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2ou1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ou1 OCA], [http://www.ebi.ac.uk/pdbsum/2ou1 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2ou1 RCSB]</span>
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==Overview==
==Overview==
Apolipoproteins A-I and A-II form the major protein constituents of high-density lipid particles (HDL), the concentration of which is inversely correlated with the frequency of heart disease in humans. Although the physiological role of apolipoprotein A-II is unclear, evidence for its involvement in free fatty acid metabolism in mice has recently been obtained. Currently, the best characterized activity of apolipoprotein A-II is its potent antagonism of the anti-atherogenic and anti-inflammatory activities of apolipoprotein A-I, probably due to its competition with the latter for lipid acyl side chains in HDL. Many interactions of apolipoprotein A-I with enzymes and proteins involved in reverse cholesterol transport and HDL maturation are mediated by lipid-bound protein. The structural bases of interaction with lipids are expected to be common to exchangeable apolipoproteins and attributable to amphipathic alpha-helices present in each of them. Thus, characterization of apolipoprotein-lipid interactions in any apolipoprotein is likely to provide information that is applicable to the entire class. We report structures of human apolipoprotein A-II and its complex with beta-octyl glucoside, a widely used lipid surrogate. The former shows that disulfide-linked dimers of apolipoprotein A-II form amphipathic alpha-helices which aggregate into tetramers. Dramatic changes, observed in the presence of beta-octyl glucoside, might provide clues to the structural basis for its antagonism of apolipoprotein A-I. Additionally, excursions of individual molecules of apolipoprotein A-II from a common helical architecture in both structures indicate that lipid-bound apolipoproteins are likely to have an ensemble of related conformations. These structures provide the first experimental paradigm for description of apolipoprotein-lipid interactions at the atomic level.
Apolipoproteins A-I and A-II form the major protein constituents of high-density lipid particles (HDL), the concentration of which is inversely correlated with the frequency of heart disease in humans. Although the physiological role of apolipoprotein A-II is unclear, evidence for its involvement in free fatty acid metabolism in mice has recently been obtained. Currently, the best characterized activity of apolipoprotein A-II is its potent antagonism of the anti-atherogenic and anti-inflammatory activities of apolipoprotein A-I, probably due to its competition with the latter for lipid acyl side chains in HDL. Many interactions of apolipoprotein A-I with enzymes and proteins involved in reverse cholesterol transport and HDL maturation are mediated by lipid-bound protein. The structural bases of interaction with lipids are expected to be common to exchangeable apolipoproteins and attributable to amphipathic alpha-helices present in each of them. Thus, characterization of apolipoprotein-lipid interactions in any apolipoprotein is likely to provide information that is applicable to the entire class. We report structures of human apolipoprotein A-II and its complex with beta-octyl glucoside, a widely used lipid surrogate. The former shows that disulfide-linked dimers of apolipoprotein A-II form amphipathic alpha-helices which aggregate into tetramers. Dramatic changes, observed in the presence of beta-octyl glucoside, might provide clues to the structural basis for its antagonism of apolipoprotein A-I. Additionally, excursions of individual molecules of apolipoprotein A-II from a common helical architecture in both structures indicate that lipid-bound apolipoproteins are likely to have an ensemble of related conformations. These structures provide the first experimental paradigm for description of apolipoprotein-lipid interactions at the atomic level.
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==Disease==
 
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Known diseases associated with this structure: Apolipoprotein A-II deficiency OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=107670 107670]], Hypercholesterolemia, familial, modification of OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=107670 107670]]
 
==About this Structure==
==About this Structure==
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[[Category: high density lipoprotein]]
[[Category: high density lipoprotein]]
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''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 18:04:28 2008''
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''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 04:23:05 2008''

Revision as of 01:23, 31 March 2008


PDB ID 2ou1

Drag the structure with the mouse to rotate
, resolution 2.0Å
Related: 1L6L


Resources: FirstGlance, OCA, PDBsum, RCSB
Coordinates: save as pdb, mmCIF, xml



Structures of apolipoprotein A-II and a lipid surrogate complex provide insights into apolipoprotein-lipid interactions


Overview

Apolipoproteins A-I and A-II form the major protein constituents of high-density lipid particles (HDL), the concentration of which is inversely correlated with the frequency of heart disease in humans. Although the physiological role of apolipoprotein A-II is unclear, evidence for its involvement in free fatty acid metabolism in mice has recently been obtained. Currently, the best characterized activity of apolipoprotein A-II is its potent antagonism of the anti-atherogenic and anti-inflammatory activities of apolipoprotein A-I, probably due to its competition with the latter for lipid acyl side chains in HDL. Many interactions of apolipoprotein A-I with enzymes and proteins involved in reverse cholesterol transport and HDL maturation are mediated by lipid-bound protein. The structural bases of interaction with lipids are expected to be common to exchangeable apolipoproteins and attributable to amphipathic alpha-helices present in each of them. Thus, characterization of apolipoprotein-lipid interactions in any apolipoprotein is likely to provide information that is applicable to the entire class. We report structures of human apolipoprotein A-II and its complex with beta-octyl glucoside, a widely used lipid surrogate. The former shows that disulfide-linked dimers of apolipoprotein A-II form amphipathic alpha-helices which aggregate into tetramers. Dramatic changes, observed in the presence of beta-octyl glucoside, might provide clues to the structural basis for its antagonism of apolipoprotein A-I. Additionally, excursions of individual molecules of apolipoprotein A-II from a common helical architecture in both structures indicate that lipid-bound apolipoproteins are likely to have an ensemble of related conformations. These structures provide the first experimental paradigm for description of apolipoprotein-lipid interactions at the atomic level.

About this Structure

2OU1 is a Single protein structure of sequence from Homo sapiens. This structure supersedes the now removed PDB entry 1L6K. Full crystallographic information is available from OCA.

Reference

Structures of apolipoprotein A-II and a lipid-surrogate complex provide insights into apolipoprotein-lipid interactions., Kumar MS, Carson M, Hussain MM, Murthy HM, Biochemistry. 2002 Oct 1;41(39):11681-91. PMID:12269810

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