3LVQ

The crystal structure of ASAP3 in complex with Arf6 in transition state

Summary for 3LVQ

• Entry DOI: 10.2210/pdb3lvq/pdb
• Related: 3LVR
• Descriptor: Arf-GAP with SH3 domain, ANK repeat and PH domain-containing protein 3, ADP-ribosylation factor 6, ZINC ION, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: arf, gap, gdp, asap3, uplc1, arf6, arfgap, linkers, alternative splicing, ank repeat, coiled coil, cytoplasm, metal-binding, phosphoprotein, polymorphism, zinc, zinc-finger, cell membrane, endosome, er-golgi transport, golgi apparatus, gtp-binding, lipoprotein, myristate, nucleotide-binding, protein transport, transport
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 1
• Total formula weight: 55467.13

Authors

Ismail, S.A.,Vetter, I.R.,Sot, B.,Wittinghofer, A. (deposition date: 2010-02-22, release date: 2010-06-09, Last modification date: 2024-10-16)

Primary citation

Ismail, S.A.,Vetter, I.R.,Sot, B.,Wittinghofer, A.
The structure of an Arf-ArfGAP complex reveals a Ca2+ regulatory mechanism
Cell(Cambridge,Mass.), 141:812-821, 2010

PubMed Abstract: Arfs are small G proteins that have a key role in vesicle trafficking and cytoskeletal remodeling. ArfGAP proteins stimulate Arf intrinsic GTP hydrolysis by a mechanism that is still unresolved. Using a fusion construct we solved the structure of the ArfGAP ASAP3 in complex with Arf6 in the transition state. This structure clarifies the ArfGAP catalytic mechanism and shows a glutamine((Arf6)) and an arginine finger((ASAP3)) as the important catalytic residues. Unexpectedly the structure shows a calcium ion, liganded by both proteins in the complex interface, stabilizing the interaction and orienting the catalytic machinery. Calcium stimulates the GAP activity of ASAPs, but not other members of the ArfGAP family. This type of regulation is unique for GAPs and any other calcium-regulated processes and hints at a crosstalk between Ca(2+) and Arf signaling.

PubMed: 20510928
DOI: 10.1016/j.cell.2010.03.051

Experimental method

X-RAY DIFFRACTION (3.38 Å)