Identifier: R-HSA-8867754
Compartment:
plasma membrane
BAR (BIN/amphiphysin/Rvs) domain proteins sense and contribute to membrane curvature. BAR domain proteins generally form long, coiled-coil homo- or hetero-dimers with a concave inner surface that interacts with membranes (reviewed in Gallop and McMahon, 2005; Daumke et al, 2014). F-BAR domain proteins such as FCHo 1 and 2 recognize shallow membrane curvature and are generally recruited early in the formation of clathrin-coated pit (Itoh et al, 2005; Kamioka et al, 2004; Henne et al, 2007; Shimada et al, 2007; Henne et al, 2010). FNBP proteins and N-BAR containing endocytic proteins such as SNX9 and 18, amphiphysin (AMPH) and endophilins recognize regions of membrane with greater curvature, interact with dynamin and likely play a later role in CCP formation with spatiotemporal coupling to vesicle scission (Kamioka et al, 2004; Itoh et al, 2005; Soulet et al, 2005; Shimada et al, 2007; Shin et al, 2008; Taylor et al, 2011; reveiwed in McMahon and Boucrot, 2011). These proteins are recruited to the complex through interactions with core components of the clathrin-coated pit, and in the case of SNX9, also through interaction with PI(3,4)P2, which is generated at late stages by clathrin-associated PIK3C2A (Lundmark and Carlson, 2003; Schmid et al, 2006; Dergai et al, 2010; Brett et al, 2002 : Posor et al, 2013; reviewed in Daumke et al, 2014). Early BAR domain containing proteins such as FCHo1 and 2 are not present in either late stage clathrin-coated pits or in free clathrin-coated vesicles. Although the precise timing of their dissociation is not known, in this pathway, they are shown leaving the clathrin-coated pit upon recruitment of the more highly curved N-BAR proteins (Taylor et al, 2011).