Visualization of HRas Domains in the Plasma Membrane of Fibroblasts.
Biophys J
; 108(8): 1870-7, 2015 Apr 21.
Article
em En
| MEDLINE
| ID: mdl-25902427
ABSTRACT
The plasma membrane is a highly complex, organized structure where the lateral organization of signaling proteins is tightly regulated. In the case of Ras proteins, it has been suggested that the differential activity of the various isoforms is due to protein localization in separate membrane compartments. To date, direct visualization of such compartmentalization has been achieved only by electron microscopy on membrane sheets. Here, we combine photoactivated light microscopy with quantitative statistical analysis to visualize protein distribution in intact cells. In particular, we focus on the localization of HRas and its minimal anchoring domain, CAAX. We demonstrate the existence of a complex partitioning behavior, where small domains coexist with larger ones. The protein content in these domains varied from two molecules to tens of molecules. We found that 40% of CAAX and 60% of HRas were localized in domains. Subsequently, we were able to manipulate protein distributions by inducing coalescence of supposedly cholesterol-enriched domains. Clustering resulted in an increase of the localized fraction by 15%.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Membrana Celular
/
Proteínas Proto-Oncogênicas p21(ras)
/
Fibroblastos
/
Proteínas de Membrana
Limite:
Animals
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article