A novel GTP-binding protein–adaptor protein complex responsible for export of Vangl2 from the trans Golgi network

Abstract

Planar cell polarity (PCP) requires the asymmetric sorting of distinct signaling receptors to distal and proximal surfaces of polarized epithelial cells. We have examined the transport of one PCP signaling protein, Vangl2, from the trans Golgi network (TGN) in mammalian cells. Using siRNA knockdown experiments, we find that the GTP-binding protein, Arfrp1, and the clathrin adaptor complex 1 (AP-1) are required for Vangl2 transport from the TGN. In contrast, TGN export of Frizzled 6, which localizes to the opposing epithelial surface from Vangl2, does not depend on Arfrp1 or AP-1. Mutagenesis studies identified a YYXXF sorting signal in the C-terminal cytosolic domain of Vangl2 that is required for Vangl2 traffic and interaction with the μ subunit of AP-1. We propose that Arfrp1 exposes a binding site on AP-1 that recognizes the Vangl2 sorting motif for capture into a transport vesicle destined for the proximal surface of a polarized epithelial cell.DOI: http://dx.doi.org/10.7554/eLife.00160.001

Control of vertebrate core PCP protein localization and dynamics by Prickle2

“…1N). This pattern might reflect the vesicular transport proteins known to be important for the processing and trafficking of Vangl proteins (Guo et al, 2013;Merte et al, 2009;Yin et al, 2012). Both the cortical localization and asymmetry of these accumulations increased as development proceeded, with a timeframe similar to that for Dvl1 and Pk2 (Fig.…”

Planar cell polarity in moving cells: think globally, act locally

“…Mutations in a number of other vertebrate genes result in PCP phenotypes, implicating these genes either in the establishment of polarized protein domains or in the reception and transduction of PCP signals uniquely in vertebrates. With respect to the establishment of PCP protein localization, Sec24b, a component of the CopII coat protein complex, trafficks Vangl2 from the endoplasmic reticulum (Merte et al, 2010;Wansleeben et al, 2010), and the GTP-binding protein Arfrp1 transports Vangl2 from the trans Golgi network (Guo et al, 2013). Additionally, the adaptor protein Gipc1 interacts with Vangl2 to promote its endocytic internalization and trafficking away from inappropriate membranes (Giese et al, 2012).…”

A BAR-Domain Protein SH3P2, Which Binds to Phosphatidylinositol 3-Phosphate and ATG8, Regulates Autophagosome Formation in Arabidopsis

“…The signals were detected following the ECL Plus immunoblot method. For the liposome flotation assay, liposomes were prepared as described previously (Guo et al, 2013). Five micrograms of His-MBP-SH3P2 or His-MBP proteins was incubated with 8 mL of 1.8 mg/mL of liposomes in HKM buffer (20 mM HEPES, pH 7.4, 100 mM KCl, and 5 mM MgCl 2 ) containing 100 mM nucleotides at room temperature.…”