1TXU

Crystal Structure of the Vps9 Domain of Rabex-5

Summary for 1TXU

• Entry DOI: 10.2210/pdb1txu/pdb
• Descriptor: Rab5 GDP/GTP exchange factor, MAGNESIUM ION (3 entities in total)
• Functional Keywords: vps9 domain, rab5 guanine-nucleotide exchange factor, gef, protein transport
• Biological source: Homo sapiens
• Cellular location: Cytoplasm : Q9UJ41
• Total number of polymer chains: 1
• Total formula weight: 32388.09

Authors

Delprato, A.,Merithew, E.,Lambright, D.G. (deposition date: 2004-07-06, release date: 2004-09-21, Last modification date: 2018-01-31)

Primary citation

Delprato, A.,Merithew, E.,Lambright, D.G.
Structure, exchange determinants, and family-wide rab specificity of the tandem helical bundle and Vps9 domains of Rabex-5
Cell(Cambridge,Mass.), 118:607-617, 2004

PubMed Abstract: The Rab5 GTPase, an essential regulator of endocytosis and endosome biogenesis, is activated by guanine-nucleotide exchange factors (GEFs) that contain a Vps9 domain. Here, we show that the catalytic core of the Rab GEF Rabex-5 has a tandem architecture consisting of a Vps9 domain stabilized by an indispensable helical bundle. A family-wide analysis of Rab specificity demonstrates high selectivity for Rab5 subfamily GTPases. Conserved exchange determinants map to a common surface of the Vps9 domain, which recognizes invariant aromatic residues in the switch regions of Rab GTPases and selects for the Rab5 subfamily by requiring a small nonacidic residue preceding a critical phenylalanine in the switch I region. These and other observations reveal unexpected similarity with the Arf exchange site in the Sec7 domain.

PubMed: 15339665
DOI: 10.1016/j.cell.2004.08.009

Experimental method

X-RAY DIFFRACTION (2.35 Å)