1epb
From Proteopedia
(New page: 200px<br /><applet load="1epb" size="450" color="white" frame="true" align="right" spinBox="true" caption="1epb, resolution 2.2Å" /> '''STRUCTURE OF THE EPID...) |
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| - | [[Image:1epb.gif|left|200px]]<br /><applet load="1epb" size=" | + | [[Image:1epb.gif|left|200px]]<br /><applet load="1epb" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1epb, resolution 2.2Å" /> | caption="1epb, resolution 2.2Å" /> | ||
'''STRUCTURE OF THE EPIDIDYMAL RETINOIC ACID-BINDING PROTEIN AT 2.1 ANGSTROMS RESOLUTION'''<br /> | '''STRUCTURE OF THE EPIDIDYMAL RETINOIC ACID-BINDING PROTEIN AT 2.1 ANGSTROMS RESOLUTION'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Androgen-dependent proteins in the lumen of the epididymis are | + | BACKGROUND: Androgen-dependent proteins in the lumen of the epididymis are required for sperm maturation. One of these is a retinoic acid binding protein, E-RABP, which binds both all-trans and 9-cis retinoic acid. The other retinoid-binding proteins whose structures are known do not bind 9-cis retinoids. RESULTS: We describe the X-ray structure determination of E-RABP with and without bound ligand. The ligand binds deep in the beta-barrel of the protein, the beta-ionone ring innermost. The binding site, like the ligand, is amphipathic and the deepest part of the cavity is formed by a ring of aromatic amino acids. The isoprene tail of all-trans retinoic acid is bound in a folded conformation which resembles that of the 9-cis isomer. CONCLUSION: E-RABP achieves high-affinity binding of both all-trans and 9-cis isomers of retinoic acid by forcing the all-trans form to bind in a folded conformation. The RAR family of nuclear receptors for retinoic acid also binds both isomers, and their binding sites may therefore be similar. |
==About this Structure== | ==About this Structure== | ||
| - | 1EPB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with REA as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1EPB is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with <scene name='pdbligand=REA:'>REA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EPB OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Rattus norvegicus]] | [[Category: Rattus norvegicus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Newcomer, M | + | [[Category: Newcomer, M E.]] |
[[Category: REA]] | [[Category: REA]] | ||
[[Category: retinoic acid-binding protein]] | [[Category: retinoic acid-binding protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:30:08 2008'' |
Revision as of 10:30, 21 February 2008
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STRUCTURE OF THE EPIDIDYMAL RETINOIC ACID-BINDING PROTEIN AT 2.1 ANGSTROMS RESOLUTION
Overview
BACKGROUND: Androgen-dependent proteins in the lumen of the epididymis are required for sperm maturation. One of these is a retinoic acid binding protein, E-RABP, which binds both all-trans and 9-cis retinoic acid. The other retinoid-binding proteins whose structures are known do not bind 9-cis retinoids. RESULTS: We describe the X-ray structure determination of E-RABP with and without bound ligand. The ligand binds deep in the beta-barrel of the protein, the beta-ionone ring innermost. The binding site, like the ligand, is amphipathic and the deepest part of the cavity is formed by a ring of aromatic amino acids. The isoprene tail of all-trans retinoic acid is bound in a folded conformation which resembles that of the 9-cis isomer. CONCLUSION: E-RABP achieves high-affinity binding of both all-trans and 9-cis isomers of retinoic acid by forcing the all-trans form to bind in a folded conformation. The RAR family of nuclear receptors for retinoic acid also binds both isomers, and their binding sites may therefore be similar.
About this Structure
1EPB is a Single protein structure of sequence from Rattus norvegicus with as ligand. Full crystallographic information is available from OCA.
Reference
Structure of the epididymal retinoic acid binding protein at 2.1 A resolution., Newcomer ME, Structure. 1993 Sep 15;1(1):7-18. PMID:8069623
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