1tr8
From Proteopedia
(New page: 200px<br /><applet load="1tr8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1tr8, resolution 2.27Å" /> '''Crystal Structure of...) |
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| - | [[Image:1tr8.gif|left|200px]]<br /><applet load="1tr8" size=" | + | [[Image:1tr8.gif|left|200px]]<br /><applet load="1tr8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1tr8, resolution 2.27Å" /> | caption="1tr8, resolution 2.27Å" /> | ||
'''Crystal Structure of archaeal Nascent Polypeptide-associated Complex (aeNAC)'''<br /> | '''Crystal Structure of archaeal Nascent Polypeptide-associated Complex (aeNAC)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Nascent polypeptide-associated complex (NAC) was identified in eukaryotes | + | Nascent polypeptide-associated complex (NAC) was identified in eukaryotes as the first cytosolic factor that contacts the nascent polypeptide chain emerging from the ribosome. NAC is highly conserved from yeast to humans. Mutations in NAC cause severe embryonically lethal phenotypes in mice, Drosophila, and Caenorhabditis elegans. NAC was suggested to protect the nascent chain from inappropriate early interactions with cytosolic factors. Eukaryotic NAC is a heterodimer with two subunits sharing substantial homology with each other. All sequenced archaebacterial genomes exhibit only one gene homologous to the NAC subunits. Here we present the first archaebacterial NAC homolog. It forms a homodimer, and as eukaryotic NAC it is associated with ribosomes and contacts the emerging nascent chain on the ribosome. We present the first crystal structure of a NAC protein revealing two structural features: (i) a novel unique protein fold that mediates dimerization of the complex, and (ii) a ubiquitin-associated domain that suggests a yet unidentified role for NAC in the cellular protein quality control system via the ubiquitination pathway. Based on the presented structure we propose a model for the eukaryotic heterodimeric NAC domain. |
==About this Structure== | ==About this Structure== | ||
| - | 1TR8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanothermobacter_marburgensis Methanothermobacter marburgensis]. Full crystallographic information is available from [http:// | + | 1TR8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanothermobacter_marburgensis Methanothermobacter marburgensis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TR8 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: ubiquitin]] | [[Category: ubiquitin]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:16:31 2008'' |
Revision as of 13:16, 21 February 2008
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Crystal Structure of archaeal Nascent Polypeptide-associated Complex (aeNAC)
Overview
Nascent polypeptide-associated complex (NAC) was identified in eukaryotes as the first cytosolic factor that contacts the nascent polypeptide chain emerging from the ribosome. NAC is highly conserved from yeast to humans. Mutations in NAC cause severe embryonically lethal phenotypes in mice, Drosophila, and Caenorhabditis elegans. NAC was suggested to protect the nascent chain from inappropriate early interactions with cytosolic factors. Eukaryotic NAC is a heterodimer with two subunits sharing substantial homology with each other. All sequenced archaebacterial genomes exhibit only one gene homologous to the NAC subunits. Here we present the first archaebacterial NAC homolog. It forms a homodimer, and as eukaryotic NAC it is associated with ribosomes and contacts the emerging nascent chain on the ribosome. We present the first crystal structure of a NAC protein revealing two structural features: (i) a novel unique protein fold that mediates dimerization of the complex, and (ii) a ubiquitin-associated domain that suggests a yet unidentified role for NAC in the cellular protein quality control system via the ubiquitination pathway. Based on the presented structure we propose a model for the eukaryotic heterodimeric NAC domain.
About this Structure
1TR8 is a Single protein structure of sequence from Methanothermobacter marburgensis. Full crystallographic information is available from OCA.
Reference
The crystal structure of archaeal nascent polypeptide-associated complex (NAC) reveals a unique fold and the presence of a ubiquitin-associated domain., Spreter T, Pech M, Beatrix B, J Biol Chem. 2005 Apr 22;280(16):15849-54. Epub 2005 Jan 22. PMID:15665334
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