期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1994
卷号：91
期号：3
页码：1114-1118
DOI：10.1073/pnas.91.3.1114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Brefeldin A (BFA) is a fungal metabolite that exerts profound and generally inhibitory actions on membrane transport. At least some of the BFA effects are due to inhibition of the GDP-GTP exchange on the ADP-ribosylation factor (ARF) catalyzed by membrane protein(s). ARF activation is likely to be a key event in the association of non-clathrin coat components, including ARF itself, onto transport organelles. ARF, in addition to participating in membrane transport, is known to function as a cofactor in the enzymatic activity of cholera toxin, a bacterial ADP-ribosyltransferase. In this study we have examined whether BFA, in addition to inhibiting membrane transport, might affect endogenous ADP-ribosylation in eukaryotic cells. Two cytosolic proteins of 38 and 50 kDa were enzymatically ADP-ribosylated in the presence of BFA in cellular extracts. The 38-kDa substrate was tentatively identified as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase. The BFA-binding components mediating inhibition of membrane traffic and stimulation of ADP-ribosylation appear to have the same ligand specificity. These data demonstrate the existence of a BFA-sensitive mono(ADP-ribosyl)transferase that may play a role in membrane movements.
