ADP-ribosylation Factor Functions Synergistically with a 50-kDa Cytosolic Factor in Cell-free Activation of Human Neutrophil Phospholipase D
Year: 1995
Type: article
Abstract: Proteins in both the cytosol and plasma membrane are needed to reconstitute cell-free phospholipase D activity from phagocytes (Olson, S., Bowman, E. P., and Lambeth, J. D. (1991) J. Biol. Chem. 266, 17236-17242); membrane factors include a small GTP-binding protein in the Rho family (Bowman, E., Uhlinger, D. J., and Lambeth, J. D. (1993) J. Biol. Chem. 268, 21509-21512). ADP-ribosylation factor (ARF) was recently implicated as the cytosolic factor, as it activates phospholipase D in HL-60 membranes. Herein, we show that ion exchange chromatography separates ARF from the major phospholipase D-stimulating cytosolic factor. Both bovine brain ARF and recombinant human ARF-1 stimulated a small amount of phospholipase D activity in the absence of cytosol (about 10% of the response seen with cytosol). With a high concentration of ARF-depleted cytosol, ARF did not further activate. However, at low cytosol, ARF caused marked activation. Thus, ARF synergizes with the cytosolic factor in phospholipase D activation.
Source: Journal of Biological Chemistry
Institution: Emory University
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
Funder: National Cancer Institute
OpenAlex ID: W2079169500