2ovr
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The ubiquitin-mediated proteolysis of cyclin E plays a central role in | + | The ubiquitin-mediated proteolysis of cyclin E plays a central role in cell-cycle progression, and cyclin E accumulation is a common event in cancer. Cyclin E degradation is triggered by multisite phosphorylation, which induces binding to the SCF(Fbw7) ubiquitin ligase complex. Structures of the Skp1-Fbw7 complex bound to cyclin E peptides identify a doubly phosphorylated pThr380/pSer384 cyclin E motif as an optimal, high-affinity degron and a singly phosphorylated pThr62 motif as a low-affinity one. Biochemical data indicate that the closely related yeast SCF(Cdc4) complex recognizes the multisite phosphorylated Sic1 substrate similarly and identify three doubly phosphorylated Sic1 degrons, each capable of high-affinity interactions with two Cdc4 phosphate binding sites. A model that explains the role of multiple cyclin E/Sic1 degrons is provided by the findings that Fbw7 and Cdc4 dimerize, that Fbw7 dimerization enhances the turnover of a weakly associated cyclin E in vivo, and that Cdc4 dimerization increases the rate and processivity of Sic1 ubiquitination in vitro. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | Structure of a Fbw7-Skp1- | + | Structure of a Fbw7-Skp1-cyclin E complex: multisite-phosphorylated substrate recognition by SCF ubiquitin ligases., Hao B, Oehlmann S, Sowa ME, Harper JW, Pavletich NP, Mol Cell. 2007 Apr 13;26(1):131-43. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17434132 17434132] |
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Hao, B.]] | [[Category: Hao, B.]] | ||
| - | [[Category: Harper, J | + | [[Category: Harper, J W.]] |
[[Category: Oehlmann, S.]] | [[Category: Oehlmann, S.]] | ||
| - | [[Category: Pavletich, N | + | [[Category: Pavletich, N P.]] |
| - | [[Category: Sowa, M | + | [[Category: Sowa, M E.]] |
[[Category: SO4]] | [[Category: SO4]] | ||
[[Category: f-box; wd40 domains; double phosphorylation]] | [[Category: f-box; wd40 domains; double phosphorylation]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:23:05 2008'' |
Revision as of 16:23, 21 February 2008
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Structure of the Skp1-Fbw7-CyclinEdegN complex
Overview
The ubiquitin-mediated proteolysis of cyclin E plays a central role in cell-cycle progression, and cyclin E accumulation is a common event in cancer. Cyclin E degradation is triggered by multisite phosphorylation, which induces binding to the SCF(Fbw7) ubiquitin ligase complex. Structures of the Skp1-Fbw7 complex bound to cyclin E peptides identify a doubly phosphorylated pThr380/pSer384 cyclin E motif as an optimal, high-affinity degron and a singly phosphorylated pThr62 motif as a low-affinity one. Biochemical data indicate that the closely related yeast SCF(Cdc4) complex recognizes the multisite phosphorylated Sic1 substrate similarly and identify three doubly phosphorylated Sic1 degrons, each capable of high-affinity interactions with two Cdc4 phosphate binding sites. A model that explains the role of multiple cyclin E/Sic1 degrons is provided by the findings that Fbw7 and Cdc4 dimerize, that Fbw7 dimerization enhances the turnover of a weakly associated cyclin E in vivo, and that Cdc4 dimerization increases the rate and processivity of Sic1 ubiquitination in vitro.
About this Structure
2OVR is a Protein complex structure of sequences from Homo sapiens with as ligand. Full crystallographic information is available from OCA.
Reference
Structure of a Fbw7-Skp1-cyclin E complex: multisite-phosphorylated substrate recognition by SCF ubiquitin ligases., Hao B, Oehlmann S, Sowa ME, Harper JW, Pavletich NP, Mol Cell. 2007 Apr 13;26(1):131-43. PMID:17434132
Page seeded by OCA on Thu Feb 21 18:23:05 2008
