Membrane-trafficking sorting hubs: Cooperation between PI4P and small GTPases at the trans-Golgi network

Department of Molecular Biology and Genetics, 107 Biotechnology Bldg., Cornell University, Ithaca, NY 14853-7202, USA.
Trends in cell biology (Impact Factor: 12.31). 07/2011; 21(9):515-25. DOI: 10.1016/j.tcb.2011.05.005
Source: PubMed

ABSTRACT Cell polarity in eukaryotes requires constant sorting, packaging and transport of membrane-bound cargo within the cell. These processes occur in two sorting hubs: the recycling endosome for incoming material and the trans-Golgi network for outgoing material. Phosphatidylinositol 3-phosphate and phosphatidylinositol 4-phosphate are enriched at the endocytic and exocytic sorting hubs, respectively, where they act together with small GTPases to recruit factors to segregate cargo and regulate carrier formation and transport. In this review, we summarize the current understanding of how these lipids and GTPases regulate membrane trafficking directly, emphasizing the recent discoveries of phosphatidylinositol 4-phosphate functions at the trans-Golgi network.

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Available from: Felipe H Santiago-Tirado, Apr 30, 2014
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    • "For example, GBF1 binding to the viral 3A protein may recruit phosphatidylinositol 4-phosphate (PI4P) to the viral replication complex. PI4P is the principle phosphoinositide in the Golgi apparatus, and it acts as a targeting signal for Golgi-associated proteins [40]. EV71 replication requires the activity of PI4P [41], and Arf1 and GBF1 were shown to generate a PI4P-enriched environment to support viral replication [20]. "
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    PLoS ONE 06/2014; 9(6):e99768. DOI:10.1371/journal.pone.0099768 · 3.23 Impact Factor
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    • "Phosphatidylinositol 4-kinases (PI4Ks) regulate key aspects of the structure and function of the Golgi apparatus via effector proteins that bind phosphatidylinositol 4-phosphate (PtdIns4P) and coordinate lipid metabolism with vesicle-mediated trafficking pathways (Graham and Burd, 2011; Santiago-Tirado and Bretscher, 2011). PtdIns4P is most abundant on membranes of the trans-Golgi network (TGN; Godi et al., 2004; Cheong et al., 2010), in which PI4Ks reside at steady state (Strahl et al., 2005). "
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