Direct identification of a G protein ubiquitination site by mass spectrometry.
Biochemistry
; 41(16): 5067-74, 2002 Apr 23.
Article
em En
| MEDLINE
| ID: mdl-11955054
ABSTRACT
Covalent attachment of ubiquitin is well-known to target proteins for degradation. Here, mass spectrometry was used to identify the site of ubiquitination in Gpa1, the G protein alpha subunit in yeast Saccharomyces cerevisiae. The modified residue is located at Lys165 within the alpha-helical domain of Galpha, a region of unknown function. Substitution of Lys165 with Arg (Gpa1(K165R)) results in a substantial decrease in ubiquitination. In addition, yeast expressing the Gpa1(K165R) mutant are moderately resistant to pheromone in growth inhibition assays-a phenotype consistent with enhanced Galpha signaling activity. These findings indicate that the alpha-helical domain may serve to regulate the turnover of Gpa1.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Heterotriméricas de Ligação ao GTP
/
Proteínas de Saccharomyces cerevisiae
/
Ubiquitina
/
Subunidades alfa de Proteínas de Ligação ao GTP
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Biochemistry
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Estados Unidos