Abstract
We have previously shown that ilimaquinone (IQ), a marine sponge metabolite, causes complete vesiculation of the Golgi stacks. By reconstituting the IQ-mediated vesiculation of the Golgi apparatus in permeabilized cells, we now demonstrate that this process does not require ARF and coatomers, which are necessary for the formation of Golgi-derived COPI vesicles. We find that IQ-mediated Golgi vesiculation is inhibited by G alpha(s)-GDP and G alpha(i3)-GDP. Interestingly, adding betagamma subunits in the absence of IQ is sufficient to vesiculate Golgi stacks. Our findings reveal that IQ-mediated Golgi vesiculation occurs through activation of heterotrimeric G proteins and that it is the free betagamma, and not the activated alpha subunit, that triggers Golgi vesiculation.
Publication types
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Animals
-
Cells, Cultured
-
Cytosol / chemistry
-
Cytosol / metabolism
-
Enzyme Inhibitors / pharmacology
-
GTP-Binding Protein alpha Subunits, Gs
-
GTP-Binding Proteins / chemistry
-
GTP-Binding Proteins / drug effects
-
GTP-Binding Proteins / metabolism*
-
Golgi Apparatus / chemistry
-
Golgi Apparatus / metabolism*
-
Guanosine 5'-O-(3-Thiotriphosphate) / pharmacology
-
Guanosine Diphosphate / analogs & derivatives
-
Guanosine Diphosphate / pharmacology
-
Guanosine Triphosphate / analogs & derivatives
-
Guanosine Triphosphate / pharmacology
-
Intracellular Membranes / chemistry
-
Intracellular Membranes / metabolism
-
Kidney / cytology
-
Quinones / pharmacology
-
Rats
-
Signal Transduction / physiology
Substances
-
Enzyme Inhibitors
-
Quinones
-
Guanosine Diphosphate
-
Guanosine 5'-O-(3-Thiotriphosphate)
-
illimaquinone
-
Guanosine Triphosphate
-
GTP-Binding Proteins
-
GTP-Binding Protein alpha Subunits, Gs