Proteome-wide identification of SUMO modification sites by mass spectrometry.
Nat Protoc
; 10(9): 1374-88, 2015 Sep.
Article
en En
| MEDLINE
| ID: mdl-26292070
ABSTRACT
The protein called 'small ubiquitin-like modifier' (SUMO) is post-translationally linked to target proteins at the É-amino group of lysine residues. This 'SUMOylation' alters the behavior of the target protein, a change that is utilized to regulate diverse cellular processes. Understanding the target-specific consequences of SUMO modification requires knowledge of the location of conjugation sites, and we have developed a straightforward protocol for the proteome-wide identification of SUMO modification sites using mass spectrometry (MS). The approach described herein requires the expression of a mutant form of SUMO, in which the residue preceding the C-terminal Gly-Gly (diGly) is replaced with a lysine (SUMO(KGG)). Digestion of SUMO(KGG) protein conjugates with endoproteinase Lys-C yields a diGly motif attached to target lysines. Peptides containing this adduct are enriched using a diGly-Lys (K-É-GG)-specific antibody and identified by MS. This diGly signature is characteristic of SUMO(KGG) conjugation alone, as no other ubiquitin-like protein (Ubl) yields this adduct upon Lys-C digestion. We have demonstrated the utility of the approach in SUMOylation studies, but, in principle, it may be adapted for the site-specific identification of proteins modified by any Ubl. Starting from cell lysis, this protocol can be completed in â¼5 d.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteómica
/
Sumoilación
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Nat Protoc
Año:
2015
Tipo del documento:
Article
País de afiliación:
Reino Unido