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2eke
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The SUMO ubiquitin-like proteins play regulatory roles in cell division, transcription, DNA repair, and protein subcellular localization. | + | The SUMO ubiquitin-like proteins play regulatory roles in cell division, transcription, DNA repair, and protein subcellular localization. Paralleling other ubiquitin-like proteins, SUMO proteins are proteolytically processed to maturity, conjugated to targets by E1-E2-E3 cascades, and subsequently recognized by specific downstream effectors containing a SUMO-binding motif (SBM). SUMO and its E2 from the budding yeast Saccharomyces cerevisiae, Smt3p and Ubc9p, are encoded by essential genes. Here we describe the 1.9 A resolution crystal structure of a non-covalent Smt3p-Ubc9p complex. Unexpectedly, a heterologous portion of the crystallized complex derived from the expression construct mimics an SBM, and binds Smt3p in a manner resembling SBM binding to human SUMO family members. In the complex, Smt3p binds a surface distal from Ubc9's catalytic cysteine. The structure implies that a single molecule of Smt3p cannot bind concurrently to both the non-covalent binding site and the catalytic cysteine of a single Ubc9p molecule. However, formation of higher-order complexes can occur, where a single Smt3p covalently linked to one Ubc9p's catalytic cysteine also binds non-covalently to another molecule of Ubc9p. Comparison with other structures from the SUMO pathway suggests that formation of the non-covalent Smt3p-Ubc9p complex occurs mutually exclusively with many other Smt3p and Ubc9p interactions in the conjugation cascade. By contrast, high-resolution insights into how Smt3p-Ubc9p can also interact with downstream recognition machineries come from contacts with the SBM mimic. Interestingly, the overall architecture of the Smt3p-Ubc9p complex is strikingly similar to recent structures from the ubiquitin pathway. The results imply that non-covalent ubiquitin-like protein-E2 complexes are conserved platforms, which function as parts of larger assemblies involved in many protein post-translational regulatory pathways. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | Structure of a SUMO-binding-motif | + | Structure of a SUMO-binding-motif mimic bound to Smt3p-Ubc9p: conservation of a non-covalent ubiquitin-like protein-E2 complex as a platform for selective interactions within a SUMO pathway., Duda DM, van Waardenburg RC, Borg LA, McGarity S, Nourse A, Waddell MB, Bjornsti MA, Schulman BA, J Mol Biol. 2007 Jun 8;369(3):619-30. Epub 2007 Apr 10. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17475278 17475278] |
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Ubiquitin--protein ligase]] | [[Category: Ubiquitin--protein ligase]] | ||
| - | [[Category: Duda, D | + | [[Category: Duda, D M.]] |
| - | [[Category: Schulman, B | + | [[Category: Schulman, B A.]] |
[[Category: sbm]] | [[Category: sbm]] | ||
[[Category: smt3]] | [[Category: smt3]] | ||
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[[Category: ubc9]] | [[Category: ubc9]] | ||
| - | ''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 17:11:55 2008'' |
Revision as of 15:11, 21 February 2008
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Structure of a SUMO-binding-motif mimic bound to Smt3p-Ubc9p: conservation of a noncovalent Ubiquitin-like protein-E2 complex as a platform for selective interactions within a SUMO pathway
Overview
The SUMO ubiquitin-like proteins play regulatory roles in cell division, transcription, DNA repair, and protein subcellular localization. Paralleling other ubiquitin-like proteins, SUMO proteins are proteolytically processed to maturity, conjugated to targets by E1-E2-E3 cascades, and subsequently recognized by specific downstream effectors containing a SUMO-binding motif (SBM). SUMO and its E2 from the budding yeast Saccharomyces cerevisiae, Smt3p and Ubc9p, are encoded by essential genes. Here we describe the 1.9 A resolution crystal structure of a non-covalent Smt3p-Ubc9p complex. Unexpectedly, a heterologous portion of the crystallized complex derived from the expression construct mimics an SBM, and binds Smt3p in a manner resembling SBM binding to human SUMO family members. In the complex, Smt3p binds a surface distal from Ubc9's catalytic cysteine. The structure implies that a single molecule of Smt3p cannot bind concurrently to both the non-covalent binding site and the catalytic cysteine of a single Ubc9p molecule. However, formation of higher-order complexes can occur, where a single Smt3p covalently linked to one Ubc9p's catalytic cysteine also binds non-covalently to another molecule of Ubc9p. Comparison with other structures from the SUMO pathway suggests that formation of the non-covalent Smt3p-Ubc9p complex occurs mutually exclusively with many other Smt3p and Ubc9p interactions in the conjugation cascade. By contrast, high-resolution insights into how Smt3p-Ubc9p can also interact with downstream recognition machineries come from contacts with the SBM mimic. Interestingly, the overall architecture of the Smt3p-Ubc9p complex is strikingly similar to recent structures from the ubiquitin pathway. The results imply that non-covalent ubiquitin-like protein-E2 complexes are conserved platforms, which function as parts of larger assemblies involved in many protein post-translational regulatory pathways.
About this Structure
2EKE is a Protein complex structure of sequences from Saccharomyces cerevisiae. Active as Ubiquitin--protein ligase, with EC number 6.3.2.19 Full crystallographic information is available from OCA.
Reference
Structure of a SUMO-binding-motif mimic bound to Smt3p-Ubc9p: conservation of a non-covalent ubiquitin-like protein-E2 complex as a platform for selective interactions within a SUMO pathway., Duda DM, van Waardenburg RC, Borg LA, McGarity S, Nourse A, Waddell MB, Bjornsti MA, Schulman BA, J Mol Biol. 2007 Jun 8;369(3):619-30. Epub 2007 Apr 10. PMID:17475278
Page seeded by OCA on Thu Feb 21 17:11:55 2008
