ARNO3, a Sec7-domain guanine nucleotide exchange factor for ADP ribosylation factor 1, is involved in the control of Golgi structure and function

• DOI: 10.1073/pnas.95.17.9926
• Publication Date: 2002-07-26T14:42:40Z
• Authors: Michel Franco; Joëlle Boretto; Sylviane Robineau; Solange Monier; Bruno Goud; Pierre Chardin; Philippe Chavrier
• Keywords: ADP ribosylation factor; Pleckstrin homology domain; Transport protein; COPI

Budding of transport vesicles in the Golgi apparatus requires recruitment coat proteins and is regulated by ADP ribosylation factor (ARF) 1. ARF1 activation promoted guanine nucleotide exchange factors (GEFs), which catalyze transition to GTP-bound ARF1. We recently have identified a human protein, ARNO (ARF nucleotide-binding-site opener), as an ARF1-GEF that shares conserved domain with yeast Sec7 protein. now describe domain-containing GEF referred ARNO3. ARNO3, well third called cytohesin-1, form family highly related identical structural organization consists central carboxy-terminal pleckstrin homology domain. show all three act vitro , whereas they no effect on ARF6, ARF protein implicated early endocytic pathway. Substrate specificity ARNO-like GEFs for depends solely Overexpression ARNO3 mammalian cells results ( i ) fragmentation apparatus, ii redistribution resident component β-COP, iii inhibition SEAP (secreted alkaline phosphatase). In contrast, distribution markers not affected. This study indicates control intracellular membrane compartment structure function through regulation specific cells.