An AP-1/clathrin coat plays a novel and essential role in forming the Weibel-Palade bodies of endothelial cells.
J Cell Biol
; 170(4): 627-36, 2005 Aug 15.
Article
em En
| MEDLINE
| ID: mdl-16087708
ABSTRACT
Clathrin provides an external scaffold to form small 50-100-nm transport vesicles. In contrast, formation of much larger dense-cored secretory granules is driven by selective aggregation of internal cargo at the trans-Golgi network; the only known role of clathrin in dense-cored secretory granules formation is to remove missorted proteins by small, coated vesicles during maturation of these spherical organelles. The formation of Weibel-Palade bodies (WPBs) is also cargo driven, but these are cigar-shaped organelles up to 5 mum long. We hypothesized that a cytoplasmic coat might be required to make these very different structures, and we found that new and forming WPBs are extensively, sometimes completely, coated. Overexpression of an AP-180 truncation mutant that prevents clathrin coat formation or reduced AP-1 expression by small interfering RNA both block WPB formation. We propose that, in contrast to other secretory granules, cargo aggregation alone is not sufficient to form immature WPBs and that an external scaffold that contains AP-1 and clathrin is essential.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Corpos de Weibel-Palade
/
Vesículas Revestidas por Clatrina
/
Complexo 1 de Proteínas Adaptadoras
/
Células Endoteliais
Limite:
Humans
Idioma:
En
Revista:
J Cell Biol
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Reino Unido