The peroxisomal receptor Pex19p forms a helical mPTS recognition domain.
EMBO J
; 29(15): 2491-500, 2010 Aug 04.
Article
em En
| MEDLINE
| ID: mdl-20531392
ABSTRACT
The protein Pex19p functions as a receptor and chaperone of peroxisomal membrane proteins (PMPs). The crystal structure of the folded C-terminal part of the receptor reveals a globular domain that displays a bundle of three long helices in an antiparallel arrangement. Complementary functional experiments, using a range of truncated Pex19p constructs, show that the structured alpha-helical domain binds PMP-targeting signal (mPTS) sequences with about 10 muM affinity. Removal of a conserved N-terminal helical segment from the mPTS recognition domain impairs the ability for mPTS binding, indicating that it forms part of the mPTS-binding site. Pex19p variants with mutations in the same sequence segment abolish correct cargo import. Our data indicate a divided N-terminal and C-terminal structural arrangement in Pex19p, which is reminiscent of a similar division in the Pex5p receptor, to allow separation of cargo-targeting signal recognition and additional functions.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Peroxissomos
/
Proteínas de Membrana
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article