1a2k
From Proteopedia
(New page: 200px<br /><applet load="1a2k" size="450" color="white" frame="true" align="right" spinBox="true" caption="1a2k, resolution 2.5Å" /> '''GDPRAN-NTF2 COMPLEX''...) |
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| - | [[Image:1a2k.gif|left|200px]]<br /><applet load="1a2k" size=" | + | [[Image:1a2k.gif|left|200px]]<br /><applet load="1a2k" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1a2k, resolution 2.5Å" /> | caption="1a2k, resolution 2.5Å" /> | ||
'''GDPRAN-NTF2 COMPLEX'''<br /> | '''GDPRAN-NTF2 COMPLEX'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Nuclear transport factor 2 (NTF2) and the Ras-family GTPase Ran are two | + | Nuclear transport factor 2 (NTF2) and the Ras-family GTPase Ran are two soluble components of the nuclear protein import machinery. NTF2 binds GDP-Ran selectively and this interaction is important for efficient nuclear protein import in vivo. We have used X-ray crystallography to determine the structure of the macromolecular complex formed between GDP-Ran and nuclear transport factor 2 (NTF2) at 2.5 A resolution. The interaction interface involves primarily the putative switch II loop of Ran (residues 65 to 78) and the hydrophobic cavity and surrounding surface of NTF2. The major contribution to the interaction made by the switch II loop accounts for the ability of NTF2 to discriminate between GDP and GTP-bound forms of Ran. The aromatic side-chain of Ran Phe72 inserts into the NTF2 cavity and accounts for 22% of the surface area buried by the interaction interface, while salt bridges are formed between Lys71 and Arg76 of Ran with Asp92/Asp94 and Glu42 of NTF2, respectively. These salt bridges account for the inhibition of the Ran-NTF2 interaction by NTF2 mutants such as E42 K and D92/94N in which the negatively charged residues surrounding the cavity were altered. Because the interaction interface maintains the positions of key Ran residues involved in binding MgGDP, NTF2 binding may help stabilize the switch state of Ran, possibly in the context of targeting it to other components of the nuclear protein import machinery to specify directionality of transport. The binding of GDP-Ran at the NTF2 cavity raises the possibility that this interaction might be modulated by a metabolite or small molecule substrate for NTF2's putative enzymatic activity. |
==About this Structure== | ==About this Structure== | ||
| - | 1A2K is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Canis_lupus_familiaris Canis lupus familiaris] and [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with MG, SO4 and GDP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1A2K is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Canis_lupus_familiaris Canis lupus familiaris] and [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=GDP:'>GDP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A2K OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Rattus norvegicus]] | [[Category: Rattus norvegicus]] | ||
| - | [[Category: Kent, H | + | [[Category: Kent, H M.]] |
| - | [[Category: Mccoy, A | + | [[Category: Mccoy, A J.]] |
[[Category: Stewart, M.]] | [[Category: Stewart, M.]] | ||
[[Category: GDP]] | [[Category: GDP]] | ||
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[[Category: gtp-binding]] | [[Category: gtp-binding]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:40:06 2008'' |
Revision as of 09:40, 21 February 2008
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GDPRAN-NTF2 COMPLEX
Overview
Nuclear transport factor 2 (NTF2) and the Ras-family GTPase Ran are two soluble components of the nuclear protein import machinery. NTF2 binds GDP-Ran selectively and this interaction is important for efficient nuclear protein import in vivo. We have used X-ray crystallography to determine the structure of the macromolecular complex formed between GDP-Ran and nuclear transport factor 2 (NTF2) at 2.5 A resolution. The interaction interface involves primarily the putative switch II loop of Ran (residues 65 to 78) and the hydrophobic cavity and surrounding surface of NTF2. The major contribution to the interaction made by the switch II loop accounts for the ability of NTF2 to discriminate between GDP and GTP-bound forms of Ran. The aromatic side-chain of Ran Phe72 inserts into the NTF2 cavity and accounts for 22% of the surface area buried by the interaction interface, while salt bridges are formed between Lys71 and Arg76 of Ran with Asp92/Asp94 and Glu42 of NTF2, respectively. These salt bridges account for the inhibition of the Ran-NTF2 interaction by NTF2 mutants such as E42 K and D92/94N in which the negatively charged residues surrounding the cavity were altered. Because the interaction interface maintains the positions of key Ran residues involved in binding MgGDP, NTF2 binding may help stabilize the switch state of Ran, possibly in the context of targeting it to other components of the nuclear protein import machinery to specify directionality of transport. The binding of GDP-Ran at the NTF2 cavity raises the possibility that this interaction might be modulated by a metabolite or small molecule substrate for NTF2's putative enzymatic activity.
About this Structure
1A2K is a Protein complex structure of sequences from Canis lupus familiaris and Rattus norvegicus with , and as ligands. Full crystallographic information is available from OCA.
Reference
Structural basis for molecular recognition between nuclear transport factor 2 (NTF2) and the GDP-bound form of the Ras-family GTPase Ran., Stewart M, Kent HM, McCoy AJ, J Mol Biol. 1998 Apr 3;277(3):635-46. PMID:9533885
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