1w9c
From Proteopedia
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
| - | CRM1/Exportin1 mediates the nuclear export of proteins bearing a | + | CRM1/Exportin1 mediates the nuclear export of proteins bearing a leucine-rich nuclear export signal (NES) by forming a cooperative ternary complex with the NES-bearing substrate and the small GTPase Ran. We present a structural model of human CRM1 based on a combination of X-ray crystallography, homology modeling, and electron microscopy. The architecture of CRM1 resembles that of the import receptor transportin1, with 19 HEAT repeats and a large loop implicated in Ran binding. Residues critical for NES recognition are identified adjacent to the cysteine residue targeted by leptomycin B (LMB), a specific CRM1 inhibitor. We present evidence that a conformational change of the Ran binding loop accounts for the cooperativity of Ran- and substrate binding and for the selective enhancement of CRM1-mediated export by the cofactor RanBP3. Our findings indicate that a single architectural and mechanistic framework can explain the divergent effects of RanGTP on substrate binding by many import and export receptors. |
==About this Structure== | ==About this Structure== | ||
| Line 16: | Line 16: | ||
[[Category: Baudin, F.]] | [[Category: Baudin, F.]] | ||
[[Category: Bauer, U.]] | [[Category: Bauer, U.]] | ||
| - | [[Category: Mattaj, I | + | [[Category: Mattaj, I W.]] |
[[Category: Moulin, M.]] | [[Category: Moulin, M.]] | ||
| - | [[Category: Muller, C | + | [[Category: Muller, C W.]] |
[[Category: Petosa, C.]] | [[Category: Petosa, C.]] | ||
[[Category: Schoehn, G.]] | [[Category: Schoehn, G.]] | ||
| Line 27: | Line 27: | ||
[[Category: nuclear protein]] | [[Category: nuclear protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:41:50 2008'' |
Revision as of 13:41, 21 February 2008
|
PROTEOLYTIC FRAGMENT OF CRM1 SPANNING SIX C-TERMINAL HEAT REPEATS
Overview
CRM1/Exportin1 mediates the nuclear export of proteins bearing a leucine-rich nuclear export signal (NES) by forming a cooperative ternary complex with the NES-bearing substrate and the small GTPase Ran. We present a structural model of human CRM1 based on a combination of X-ray crystallography, homology modeling, and electron microscopy. The architecture of CRM1 resembles that of the import receptor transportin1, with 19 HEAT repeats and a large loop implicated in Ran binding. Residues critical for NES recognition are identified adjacent to the cysteine residue targeted by leptomycin B (LMB), a specific CRM1 inhibitor. We present evidence that a conformational change of the Ran binding loop accounts for the cooperativity of Ran- and substrate binding and for the selective enhancement of CRM1-mediated export by the cofactor RanBP3. Our findings indicate that a single architectural and mechanistic framework can explain the divergent effects of RanGTP on substrate binding by many import and export receptors.
About this Structure
1W9C is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Architecture of CRM1/Exportin1 suggests how cooperativity is achieved during formation of a nuclear export complex., Petosa C, Schoehn G, Askjaer P, Bauer U, Moulin M, Steuerwald U, Soler-Lopez M, Baudin F, Mattaj IW, Muller CW, Mol Cell. 2004 Dec 3;16(5):761-75. PMID:15574331
Page seeded by OCA on Thu Feb 21 15:41:50 2008
