2nup

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'''Crystal Structure of the human Sec23a/24a heterodimer, complexed with the SNARE protein Sec22b'''
'''Crystal Structure of the human Sec23a/24a heterodimer, complexed with the SNARE protein Sec22b'''
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==Overview==
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The mechanism of cargo concentration into ER-derived vesicles involves interactions between the COPII vesicular coat complex and cargo transport signals--peptide sequences of 10-15 residues. The SNARE protein Sec22 contains a signal that binds the COPII subcomplex Sec23/24 and specifies its endoplasmic reticulum (ER) exit as an unassembled SNARE. The 200 kDa crystal structure of Sec22 bound to Sec23/24 reveals that the transport signal is a folded epitope rather than a conventional short peptide sequence. The NIE segment of the SNARE motif folds against the N-terminal longin domain, and this closed form of Sec22 binds at the Sec23/24 interface. Thus, COPII recognizes unassembled Sec22 via a folded epitope, whereas Sec22 assembly into SNARE complexes would mask the NIE segment. The concept of a conformational epitope as a transport signal suggests packaging mechanisms in which a coat is sensitive to the folded state of a cargo protein or the assembled state of a multiprotein complex.
==Disease==
==Disease==
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==About this Structure==
==About this Structure==
2NUP is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2NUP OCA].
2NUP is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2NUP OCA].
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==Reference==
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The transport signal on Sec22 for packaging into COPII-coated vesicles is a conformational epitope., Mancias JD, Goldberg J, Mol Cell. 2007 May 11;26(3):403-14. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17499046 17499046]
[[Category: Homo sapiens]]
[[Category: Homo sapiens]]
[[Category: Protein complex]]
[[Category: Protein complex]]
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[[Category: Mancias, J D.]]
[[Category: Mancias, J D.]]
[[Category: Human copii sec23/24 complexed with sec22]]
[[Category: Human copii sec23/24 complexed with sec22]]
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''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 09:56:01 2008''
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[[Category: Protein transport]]
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''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Jun 5 10:08:11 2008''

Revision as of 07:08, 5 June 2008

Template:STRUCTURE 2nup

Crystal Structure of the human Sec23a/24a heterodimer, complexed with the SNARE protein Sec22b


Contents

Overview

The mechanism of cargo concentration into ER-derived vesicles involves interactions between the COPII vesicular coat complex and cargo transport signals--peptide sequences of 10-15 residues. The SNARE protein Sec22 contains a signal that binds the COPII subcomplex Sec23/24 and specifies its endoplasmic reticulum (ER) exit as an unassembled SNARE. The 200 kDa crystal structure of Sec22 bound to Sec23/24 reveals that the transport signal is a folded epitope rather than a conventional short peptide sequence. The NIE segment of the SNARE motif folds against the N-terminal longin domain, and this closed form of Sec22 binds at the Sec23/24 interface. Thus, COPII recognizes unassembled Sec22 via a folded epitope, whereas Sec22 assembly into SNARE complexes would mask the NIE segment. The concept of a conformational epitope as a transport signal suggests packaging mechanisms in which a coat is sensitive to the folded state of a cargo protein or the assembled state of a multiprotein complex.

Disease

Known disease associated with this structure: Craniolenticulosutural dysplasia OMIM:[610511]

About this Structure

2NUP is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.

Reference

The transport signal on Sec22 for packaging into COPII-coated vesicles is a conformational epitope., Mancias JD, Goldberg J, Mol Cell. 2007 May 11;26(3):403-14. PMID:17499046 Page seeded by OCA on Thu Jun 5 10:08:11 2008

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