Arfs, phosphoinositides and membrane traffic.
Arf (ADP-ribosylation factor) GTP-binding proteins function in cells to regulate membrane traffic and structure. Arfs accomplish this task through modification of membrane lipids and the recruitment of proteins, including coat proteins and actin, to membrane surfaces. Arf1 and Arf6 are the most divergent and most studied human Arf proteins that localize predominantly to the Golgi complex and plasma membrane respectively. We have been studying the targeting of Arf1 and Arf6 to these specific compartments and the common and divergent activities that they exert on these membranes. We have found that Arf6 acts through activation of type I phosphatidylinositol 4-phosphate 5-kinases to generate phosphatidylinositol 4,5-bisphosphate and that this activity is instrumental in facilitating the actin cytoskeletal rearrangements and alterations in endosomal membrane trafficking observed with increased Arf6 activation. Arf1 can also stimulate the activity of phosphatidylinositol kinases and recruit coat proteins and actin cytoskeletal elements to the Golgi complex.
Donaldson
J G
JG
Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, Rm 2503, Bethesda, MD 20892, USA. jdonalds@helix.nih.gov
D020823:ADP-Ribosylation Factor 1 / Q000378:metabolism*; D000089982:ADP-Ribosylation Factor 6; D020727:ADP-Ribosylation Factors / Q000378:metabolism*; D001692:Biological Transport / Q000502:physiology; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D004705:Endocytosis / Q000502:physiology*; D011992:Endosomes / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015778:Minor Histocompatibility Antigens; D010716:Phosphatidylinositols / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism
D000089982:ADP-Ribosylation Factor 6; D015778:Minor Histocompatibility Antigens; D010716:Phosphatidylinositols; D017853:Phosphotransferases (Alcohol Group Acceptor); C402182:phosphatidylinositol phosphate 4-kinase; D020823:ADP-Ribosylation Factor 1; D020727:ADP-Ribosylation Factors; C000715348:ARF6 protein, human