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2fif
From Proteopedia
| |||||||
| , resolution 2.49Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | RABGEF1, RABEX5 (Bos taurus) | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of a Bovine Rabex-5 fragment complexed with ubiquitin
Overview
Rabex-5 is an exchange factor for Rab5, a master regulator of endosomal trafficking. Rabex-5 binds monoubiquitin, undergoes covalent ubiquitination and contains an intrinsic ubiquitin ligase activity, all of which require an N-terminal A20 zinc finger followed immediately by a helix. The structure of the N-terminal portion of Rabex-5 bound to ubiquitin at 2.5-A resolution shows that Rabex-5-ubiquitin interactions occur at two sites. The first site is a new type of ubiquitin-binding domain, an inverted ubiquitin-interacting motif, which binds with approximately 29-microM affinity to the canonical Ile44 hydrophobic patch on ubiquitin. The second is a diaromatic patch on the A20 zinc finger, which binds with approximately 22-microM affinity to a polar region centered on Asp58 of ubiquitin. The A20 zinc-finger diaromatic patch mediates ubiquitin-ligase activity by directly recruiting a ubiquitin-loaded ubiquitin-conjugating enzyme.
About this Structure
2FIF is a Protein complex structure of sequences from Bos taurus. Full crystallographic information is available from OCA.
Reference
Structural basis for ubiquitin recognition and autoubiquitination by Rabex-5., Lee S, Tsai YC, Mattera R, Smith WJ, Kostelansky MS, Weissman AM, Bonifacino JS, Hurley JH, Nat Struct Mol Biol. 2006 Mar;13(3):264-71. Epub 2006 Feb 5. PMID:16462746
Page seeded by OCA on Mon Mar 31 03:03:14 2008
