Adenosyl ribosylation factor
| Adenosyl ribosylation factor | ||
|---|---|---|
|
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| Surface model of the ARF1-GDP-magnesium complex, according to PDB 1HUR | ||
| Mass / length primary structure | 174-180 amino acids | |
| Identifier | ||
| Gene name (s) | ARF1 , ARF3 , ARF4 , ARF5 , ARF6 | |
| External IDs | ||
| Occurrence | ||
| Homology family | ARF / ARF-like | |
| Parent taxon | Chordates | |
Adenosyl ribosylation factor ( ARF ) (also ADP ribosylation factor) is a protein that belongs to the family of small GTPases . It exists in several subversions (ARF1-6), the molecular mass of which is in the range of 21 kDa .
An important role for ARF1 in the study of cholera infection was discovered . It serves as a cofactor for permanent ADP-ribosylation of the adenylate cyclase- stimulating subunit of a trimeric G protein . The resulting increase in cAMP in the intestinal cells results in the diarrhea typical of cholera .
Another important function of ARF1 is the switch function in the genesis of intracellular protein transport vesicles in the Golgi apparatus . There it changes cyclically between a GTP- and GDP-bound form and recruits the envelope proteins necessary for vesicle formation, which are then put together and pinch off the vesicle from the membrane. The cyclic nucleotide change is catalyzed by nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs).
Like all GTPases, ARF also has a central Mg 2+ ion, which is necessary for the complexation of the GTP nucleotide.
Web links
- Gillespie / reactome: COPI Mediated Transport
- Gillespie / reactome: trans-Golgi Network Vesicle Budding
- Gillespie / reactome: Formation of a Nef: ARF1: CD4 complex