Structural highlights
Function
[ARF2_MOUSE] GTP-binding protein that functions as an allosteric activator of the cholera toxin catalytic subunit, an ADP-ribosyltransferase. Involved in protein trafficking; may modulate vesicle budding and uncoating within the Golgi apparatus. [GGA1_HUMAN] Plays a role in protein sorting and trafficking between the trans-Golgi network (TGN) and endosomes. Mediates the ARF-dependent recruitment of clathrin to the TGN and binds ubiquitinated proteins and membrane cargo molecules with a cytosolic acidic cluster-dileucine (AC-LL) motif.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
GGAs are critical for trafficking soluble proteins from the trans-Golgi network (TGN) to endosomes/lysosomes through interactions with TGN-sorting receptors, ADP-ribosylation factor (ARF) and clathrin. ARF-GTP bound to TGN membranes recruits its effector GGA by binding to the GAT domain, thus facilitating recognition of GGA for cargo-loaded receptors. Here we report the X-ray crystal structures of the human GGA1-GAT domain and the complex between ARF1-GTP and the N-terminal region of the GAT domain. When unbound, the GAT domain forms an elongated bundle of three a-helices with a hydrophobic core. Structurally, this domain, combined with the preceding VHS domain, resembles CALM, an AP180 homolog involved in endocytosis. In the complex with ARF1-GTP, a helix-loop-helix of the N-terminal part of GGA1-GAT interacts with the switches 1 and 2 of ARF1 predominantly in a hydrophobic manner. These data reveal a molecular mechanism underlying membrane recruitment of adaptor proteins by ARF-GTP.
Molecular mechanism of membrane recruitment of GGA by ARF in lysosomal protein transport.,Shiba T, Kawasaki M, Takatsu H, Nogi T, Matsugaki N, Igarashi N, Suzuki M, Kato R, Nakayama K, Wakatsuki S Nat Struct Biol. 2003 May;10(5):386-93. PMID:12679809[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Puertollano R, Randazzo PA, Presley JF, Hartnell LM, Bonifacino JS. The GGAs promote ARF-dependent recruitment of clathrin to the TGN. Cell. 2001 Apr 6;105(1):93-102. PMID:11301005
- ↑ Shiba T, Kawasaki M, Takatsu H, Nogi T, Matsugaki N, Igarashi N, Suzuki M, Kato R, Nakayama K, Wakatsuki S. Molecular mechanism of membrane recruitment of GGA by ARF in lysosomal protein transport. Nat Struct Biol. 2003 May;10(5):386-93. PMID:12679809 doi:http://dx.doi.org/10.1038/nsb920
