The small ubiquitin-related modifier SUMO is a highly conserved member of the ubiquitin/ubiquitin-like protein family involved in post-translational modification of target proteins. The importance of the SUMOylation pathway is underscored by its involvement in all developmental stages in multicellular organisms. Unlike ubiquitin, which generally targets substrates for degradation by the 26S proteasome, SUMO does not target proteins for degradation, but is known to be involved in several pathways including signal transduction, transcription, chromatin remodeling, DMA repair, mitosis, viral infection, and nucleocytoplasmic trafficking. Several tumor suppressors such as the promyelocytic leukemia protein (PML) and p53 are SUMO modified as part of their normal regulation. Nonetheless, the mechanisms underlying its regulation still remain unclear. Using a multi-faceted approach, employing x-ray crystallography, yeast genetics and biochemical analysis, I intend to structurally and functionally characterize SUMO in complex with the E1 and E2 enzymes of the SUMO conjugation pathway. This structure, along with biochemical analysis, will provide a model for SUMO activation and transfer to an E2, advancing our current understanding of the molecular mechanisms underlying SUMO activation, as well as activation of other ubiquitin/ubiquitin-like proteins. This study, combined with previous structural studies, will offer a unique opportunity to understand the molecular recognition of SUMO, providing a basis to redesign a SUMO molecule with the ability to be precisely modulated by components of the pathway. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32GM075695-01
Application #
6998689
Study Section
Special Emphasis Panel (ZRG1-F04B (20))
Program Officer
Marino, Pamela
Project Start
2005-09-01
Project End
2008-08-31
Budget Start
2005-09-01
Budget End
2006-08-31
Support Year
1
Fiscal Year
2005
Total Cost
$42,068
Indirect Cost
Name
Sloan-Kettering Institute for Cancer Research
Department
Type
DUNS #
064931884
City
New York
State
NY
Country
United States
Zip Code
10065
Olsen, Shaun K; Capili, Allan D; Lu, Xuequan et al. (2010) Active site remodelling accompanies thioester bond formation in the SUMO E1. Nature 463:906-12
Lu, Xuequan; Olsen, Shaun K; Capili, Allan D et al. (2010) Designed semisynthetic protein inhibitors of Ub/Ubl E1 activating enzymes. J Am Chem Soc 132:1748-9
Mohideen, Firaz; Capili, Allan D; Bilimoria, Parizad M et al. (2009) A molecular basis for phosphorylation-dependent SUMO conjugation by the E2 UBC9. Nat Struct Mol Biol 16:945-52
Capili, Allan D; Lima, Christopher D (2007) Taking it step by step: mechanistic insights from structural studies of ubiquitin/ubiquitin-like protein modification pathways. Curr Opin Struct Biol 17:726-35
Capili, Allan D; Lima, Christopher D (2007) Structure and analysis of a complex between SUMO and Ubc9 illustrates features of a conserved E2-Ubl interaction. J Mol Biol 369:608-18