1gqf
From Proteopedia
(New page: 200px<br /><applet load="1gqf" size="450" color="white" frame="true" align="right" spinBox="true" caption="1gqf, resolution 2.90Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1gqf.gif|left|200px]]<br /><applet load="1gqf" size=" | + | [[Image:1gqf.gif|left|200px]]<br /><applet load="1gqf" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1gqf, resolution 2.90Å" /> | caption="1gqf, resolution 2.90Å" /> | ||
'''CRYSTAL STRUCTURE OF HUMAN PROCASPASE-7'''<br /> | '''CRYSTAL STRUCTURE OF HUMAN PROCASPASE-7'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Caspases form a family of proteinases required for the initiation and | + | Caspases form a family of proteinases required for the initiation and execution phases of apoptosis. Distinct proapoptotic stimuli lead to activation of the initiator caspases-8 and -9, which in turn activate the common executioner caspases-3 and -7 by proteolytic cleavage. Whereas crystal structures of several active caspases have been reported, no three-dimensional structure of an uncleaved caspase zymogen is available so far. We have determined the 2.9-A crystal structure of recombinant human C285A procaspase-7 and have elucidated the activation mechanism of caspases. The overall fold of the homodimeric procaspase-7 resembles that of the active tetrameric caspase-7. Each monomer is organized in two structured subdomains connected by partially flexible linkers, which asymmetrically occupy and block the central cavity, a typical feature of active caspases. This blockage is incompatible with a functional substrate binding site/active site. After proteolytic cleavage within the flexible linkers, the newly formed chain termini leave the cavity and fold outward to form stable structures. These conformational changes are associated with the formation of an intact active-site cleft. Therefore, this mechanism represents a formerly unknown type of proteinase zymogen activation. |
==About this Structure== | ==About this Structure== | ||
| - | 1GQF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1GQF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GQF OCA]. |
==Reference== | ==Reference== | ||
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[[Category: zymogen]] | [[Category: zymogen]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:52:51 2008'' |
Revision as of 10:52, 21 February 2008
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CRYSTAL STRUCTURE OF HUMAN PROCASPASE-7
Overview
Caspases form a family of proteinases required for the initiation and execution phases of apoptosis. Distinct proapoptotic stimuli lead to activation of the initiator caspases-8 and -9, which in turn activate the common executioner caspases-3 and -7 by proteolytic cleavage. Whereas crystal structures of several active caspases have been reported, no three-dimensional structure of an uncleaved caspase zymogen is available so far. We have determined the 2.9-A crystal structure of recombinant human C285A procaspase-7 and have elucidated the activation mechanism of caspases. The overall fold of the homodimeric procaspase-7 resembles that of the active tetrameric caspase-7. Each monomer is organized in two structured subdomains connected by partially flexible linkers, which asymmetrically occupy and block the central cavity, a typical feature of active caspases. This blockage is incompatible with a functional substrate binding site/active site. After proteolytic cleavage within the flexible linkers, the newly formed chain termini leave the cavity and fold outward to form stable structures. These conformational changes are associated with the formation of an intact active-site cleft. Therefore, this mechanism represents a formerly unknown type of proteinase zymogen activation.
About this Structure
1GQF is a Single protein structure of sequence from Homo sapiens with as ligand. Full crystallographic information is available from OCA.
Reference
Structural basis for the activation of human procaspase-7., Riedl SJ, Fuentes-Prior P, Renatus M, Kairies N, Krapp S, Huber R, Salvesen GS, Bode W, Proc Natl Acad Sci U S A. 2001 Dec 18;98(26):14790-5. PMID:11752425
Page seeded by OCA on Thu Feb 21 12:52:51 2008
Categories: Homo sapiens | Single protein | Bode, W. | Fuentes-Prior, P. | Riedl, S. | SO4 | Apoptosis | Caspase-7 | Hydrolase | Zymogen
