Inhibition by brefeldin A of a Golgi membrane enzyme that catalyses exchange of guanine nucleotide bound to ARF

  title={Inhibition by brefeldin A of a Golgi membrane enzyme that catalyses exchange of guanine nucleotide bound to ARF},
  author={J. Bernd Helms and James E. Rothman},
A WIDE variety of membrane transformations important in intracellular transport are inhibited by the fungal metabolite brefeldin A (refs 1–4), implying that the target for this drug is central to the formation and maintenance of subcellular compartments5. Brefeldin A added to cells causes the rapid and reversible dissociation of a Golgi-associated peripheral membrane protein ( Mr 110,000)6 which was found to be identical to one of the subunits of the coat of Golgi-derived (non-clathrin) coated… 
Dissociation of Coatomer from Membranes Is Required for Brefeldin A–induced Transfer of Golgi Enzymes to the Endoplasmic Reticulum
The results suggest that enhanced binding of coatomer to membranes completely inhibits the BFA-induced retrograde transport of Golgi resident proteins to the ER, but does not interfere with the disassembly of the stacked Golgi cisternae and recycling of KDEL receptor to the IC.
Structural basis for the inhibitory effect of brefeldin A on guanine nucleotide-exchange proteins for ADP-ribosylation factors.
Chimeric molecules constructed by using sequences from the Sec7 domains of BFA-sensitive yeast Sec7 protein (ySec7d) and the insensitive human cytohesin-1 (C-1Sec7) were constructed, demonstrating that Asp965 and Met975 in ySec7D are major molecular determinants of B FA sensitivity.
Nucleotide exchange on ARF mediated by yeast Geal protein
It is proposed that Geal and ARNO, a human protein with a homologous Sec7 domain7, are members of a new family of ARF guanine-nucleotide exchange factors.
Molecular Cloning and Functional Characterization of Brefeldin A-ADP-ribosylated Substrate
The results suggest that BARS exerts a negative control on Golgi tubulation, with important consequences for the structure and function of the Golgi complex.
Purification and Cloning of a Brefeldin A-inhibited Guanine Nucleotide-exchange Protein for ADP-ribosylation Factors*
Two new clones for the ∼200-kDa BIG1 and BIG2 should facilitate characterization of this rather different family of proteins as well as the elucidation of mechanisms of regulation of BFA-sensitive ARF function in Golgi transport.
Comparative Activity of ADP-ribosylation Factor Family Members in the Early Steps of Coated Vesicle Formation on Rat Liver Golgi Membranes*
We have compared the abilities of mammalian ADP-ribosylation factors (ARFs) 1, 5, and 6 and Saccharomyces cerevisiae ARF2 to serve as substrates for the rat liver Golgi membrane guanine nucleotide
Brefeldin A-dependent membrane tubule formation reconstituted in vitro is driven by a cell cycle-regulated microtubule motor.
The results suggest that either the ATPase or microtubule-binding activity of the relevant motor is cell cycle regulated and this transport process in vitro using Xenopus egg cytosol and rat liver Golgi-enriched membrane fraction.
Binding of the cytosolic p200 protein to Golgi membranes is regulated by heterotrimeric G proteins.
The data presented here support the conclusion that the binding of the p200 protein to Golgi membranes involves regulation by the pertussis toxin-sensitive heterotrimeric G proteins, specifically the G alpha i-3 protein.
A family of ADP-ribosylation factor effectors that can alter membrane transport through the trans-Golgi.
It is proposed that GGAs are effectors for ARFs that function in the regulation of membrane traffic through the TGN, and these proteins have been named Golgi-localizing, gamma-adaptin ear homology domain, ARF-binding proteins, or GGAs.


Binding of ARF and beta-COP to Golgi membranes: possible regulation by a trimeric G protein.
Evidence is presented that a small guanosine triphosphate (GTP)-binding protein, the adenosine diphosphate ribosylation factor (ARF), reversibly associates with the Golgi apparatus in an energy, GTP, and fungal metabolite brefeldin A (BFA)-sensitive manner similar to, but distinguishable from, the 110-kilodalton cytosolic coat protein beta-COP.
ADP-ribosylation factor, a small GTP-binding protein, is required for binding of the coatomer protein beta-COP to Golgi membranes.
It is shown that Golgi coat protein binding involves a sequential reaction where an initial interaction of ARF and GTP[gamma S] with the membrane allows subsequent binding of beta-COP to take place in the absence of free ARF or free GTP, and the fungal metabolite brefeldin A is shown to exert this effect by interfering with the initial ARF-membrane interaction step.
Brefeldin A causes disassembly of the Golgi complex and accumulation of secretory proteins in the endoplasmic reticulum.
Results indicate that BFA primarily blocks the protein transport from the ER to the Golgi complex, consistent with the biochemical data previously reported.
A role for ADP-ribosylation factor in nuclear vesicle dynamics
It is reported here that purified ARF1 and GGBF have GTP-dependent soluble factor activity in the nuclear vesicle fusion assay, showing that the function of ARF is not limited to the Golgi apparatus, and indicating that there may be a link between the formation ofnuclear vesicles during mitosis and proteins involved in secretion.
ADP-ribosylation factor is functionally and physically associated with the Golgi complex.
Genetic and immunofluorescence results indicate that ARF functions in intracellular protein transport to or within the Golgi apparatus, a role not predicted by the previous in vitro biochemical studies.