ADRP is dissociated from lipid droplets by ARF1-dependent mechanism

• Published in: Biochemical and biophysical research communications 2004-09, Vol.322 (3), p.957-965
• Main Authors: Nakamura, Noriko, Akashi, Tomohiro, Taneda, Tsuya, Kogo, Hiroshi, Kikuchi, Akihiko, Fujimoto, Toyoshi
• Format: Article
• Language: English
• Subjects: 3T3 Cells; ADP-Ribosylation Factor 1 - physiology; ADRP; Animals; ARF1; Brefeldin A; Brefeldin A - pharmacology; Cell Line, Tumor; Cercopithecus aethiops; COS Cells; Guanosine Diphosphate - metabolism; Humans; Lipid droplet; Lipids - physiology; Membrane Proteins - drug effects; Membrane Proteins - physiology; Mice; Mice, Inbred BALB C; Perilipin-2; Recombinant Fusion Proteins - drug effects; Recombinant Fusion Proteins - metabolism; Recombinant Proteins - metabolism; Yeast two-hybrid
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2004.08.010

Adipocyte differentiation-related protein (ADRP) is a member of PAT proteins existing in lipid droplets (LDs). By yeast two-hybrid screening, we identified ADP-ribosylation factor 1 (ARF1) as a binding partner of ADRP. The interaction of ADRP and ARF1 was verified by GST pull-down and co-immunoprecipitation experiments. Interestingly, ADRP precipitated the GDP-bound ARF1 preferentially to the GTP-bound ARF1. Consistent with this, either brefeldin A (BFA), a fungal metabolite to inhibit ARF-GEF, or a dominant-negative mutant of ARF1 caused dissociation of ADRP from LD. On the other hand, overexpression of wild-type ARF1 did not promote the ADRP dissociation or new LD formation. By using deletion mutants, a central domain of ADRP, which is dispensable for LD binding, was shown to bind to ARF1. The present study showed that the GDP-bound ARF1 induces dissociation of ADRP from the LD surface, and that LD is a target of BFA action.