The ADP-ribosylation factor family of small GTP-binding proteins are implicated in the regulation of vesicular transport and control of cytoskeletal and cell adhesion events. The phosphoinositide 3-kinase, phosphoinositide 4-P 5-kinase and phospholipase D signaling pathways are major regulators of ARF signaling cascades. Two families of ARF regulatory molecules, the cytohesin ARF-Guanine nucleotide Exchange Factors and the centaurin GTPase-Activating Proteins provide key targets for the action of these lipid signals. A critical feature of the regulation of ARF signaling is coordinated recruitment of exchange factors, ARFs and GAPs to appropriate subcellular locations. These complexes drive repetitive cycles of ARF activation and membrane association that... |