Structural basis for membrane binding specificity of the Bin/Amphiphysin/Rvs (BAR) domain of Arfaptin-2 determined by Arl1 GTPase.
J Biol Chem
; 287(30): 25478-89, 2012 Jul 20.
Article
em En
| MEDLINE
| ID: mdl-22679020
ABSTRACT
Membrane-sculpting BAR (Bin/Amphiphysin/Rvs) domains form a crescent-shaped homodimer that can sense and induce membrane curvature through its positively charged concave face. We have recently shown that Arfaptin-2, which was originally identified as a binding partner for the Arf and Rac1 GTPases, binds to Arl1 through its BAR domain and is recruited onto Golgi membranes. There, Arfaptin-2 induces membrane tubules. Here, we report the crystal structure of the Arfaptin-2 BAR homodimer in complex with two Arl1 molecules bound symmetrically to each side, leaving the concave face open for membrane association. The overall structure of the Arl1·Arfaptin-2 BAR complex closely resembles that of the PX-BAR domain of sorting nexin 9, suggesting similar mechanisms underlying BAR domain targeting to specific organellar membranes. The Arl1·Arfaptin-2 BAR structure suggests that one of the two Arl1 molecules competes with Rac1, which binds to the concave face of the Arfaptin-2 BAR homodimer and may hinder its membrane association.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fatores de Ribosilação do ADP
/
Proteínas Adaptadoras de Transdução de Sinal
/
Multimerização Proteica
/
Proteínas de Membrana
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article