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1zp2
From Proteopedia
(New page: 200px<br /><applet load="1zp2" size="450" color="white" frame="true" align="right" spinBox="true" caption="1zp2, resolution 3.0Å" /> '''Structure of the Medi...) |
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| - | [[Image:1zp2.gif|left|200px]]<br /><applet load="1zp2" size=" | + | [[Image:1zp2.gif|left|200px]]<br /><applet load="1zp2" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1zp2, resolution 3.0Å" /> | caption="1zp2, resolution 3.0Å" /> | ||
'''Structure of the Mediator subunit cyclin C'''<br /> | '''Structure of the Mediator subunit cyclin C'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Cyclin C binds the cyclin-dependent kinases CDK8 and CDK3, which regulate | + | Cyclin C binds the cyclin-dependent kinases CDK8 and CDK3, which regulate mRNA transcription and the cell cycle, respectively. The crystal structure of cyclin C reveals two canonical five-helix repeats and a specific N-terminal helix. In contrast to other cyclins, the N-terminal helix is short, mobile, and in an exposed position that allows for interactions with proteins other than the CDKs. A model of the CDK8/cyclin C pair reveals two regions in the interface with apparently distinct roles. A conserved region explains promiscuous binding of cyclin C to CDK8 and CDK3, and a non-conserved region may be responsible for discrimination of CDK8 against other CDKs involved in transcription. A conserved and cyclin C-specific surface groove may recruit substrates near the CDK8 active site. Activation of CDKs generally involves phosphorylation of a loop at a threonine residue. In CDK8, this loop is longer and the threonine is absent, suggesting an alternative mechanism of activation that we discuss based on a CDK8-cyclin C model. |
==About this Structure== | ==About this Structure== | ||
| - | 1ZP2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Schizosaccharomyces_pombe Schizosaccharomyces pombe]. Full crystallographic information is available from [http:// | + | 1ZP2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Schizosaccharomyces_pombe Schizosaccharomyces pombe]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZP2 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: cyclin repeat domains]] | [[Category: cyclin repeat domains]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:17:43 2008'' |
Revision as of 14:17, 21 February 2008
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Structure of the Mediator subunit cyclin C
Overview
Cyclin C binds the cyclin-dependent kinases CDK8 and CDK3, which regulate mRNA transcription and the cell cycle, respectively. The crystal structure of cyclin C reveals two canonical five-helix repeats and a specific N-terminal helix. In contrast to other cyclins, the N-terminal helix is short, mobile, and in an exposed position that allows for interactions with proteins other than the CDKs. A model of the CDK8/cyclin C pair reveals two regions in the interface with apparently distinct roles. A conserved region explains promiscuous binding of cyclin C to CDK8 and CDK3, and a non-conserved region may be responsible for discrimination of CDK8 against other CDKs involved in transcription. A conserved and cyclin C-specific surface groove may recruit substrates near the CDK8 active site. Activation of CDKs generally involves phosphorylation of a loop at a threonine residue. In CDK8, this loop is longer and the threonine is absent, suggesting an alternative mechanism of activation that we discuss based on a CDK8-cyclin C model.
About this Structure
1ZP2 is a Single protein structure of sequence from Schizosaccharomyces pombe. Full crystallographic information is available from OCA.
Reference
Structure of the mediator subunit cyclin C and its implications for CDK8 function., Hoeppner S, Baumli S, Cramer P, J Mol Biol. 2005 Jul 29;350(5):833-42. PMID:15979093
Page seeded by OCA on Thu Feb 21 16:17:43 2008
