2jx5
From Proteopedia
(New page: 200px<br /><applet load="2jx5" size="350" color="white" frame="true" align="right" spinBox="true" caption="2jx5" /> '''Solution structure of the ubiquitin domain N...) |
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==Overview== | ==Overview== | ||
| - | Encoded by a multigene family, ubiquitin is expressed in the form of three | + | Encoded by a multigene family, ubiquitin is expressed in the form of three precursor proteins, two of which are fusions to the ribosomal subunits S27a and L40. Ubiquitin assists in ribosome biogenesis and also functions as a post-translational modifier after its release from S27a or L40. However, several species do not conserve the ribosomal ubiquitin domains. We report here the solution structure of a distant variant of ubiquitin, found at the N-terminus of S27a in Giardia lamblia, referred to as GlUb(S27a). Despite the considerable evolutionary distance that separates ubiquitin from GlUb(S27a), the structure of GlUb(S27a) is largely identical to that of ubiquitin. The variant domain remains attached to S27a and is part of the assembled holoribosome. Thus, conservation of tertiary structure suggests a role of this variant as a chaperone, while conservation of the primary structure--necessary for ubiquitin's function as a post-translational modifier--is no longer required. Based on these observations, we propose a model to explain the origin of the widespread ubiquitin superfold in eukaryotes. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Catic, A.]] | [[Category: Catic, A.]] | ||
[[Category: Misaghi, S.]] | [[Category: Misaghi, S.]] | ||
| - | [[Category: Ploegh, H | + | [[Category: Ploegh, H L.]] |
| - | [[Category: Ratner, D | + | [[Category: Ratner, D M.]] |
[[Category: Samuelson, J.]] | [[Category: Samuelson, J.]] | ||
[[Category: Spooner, E.]] | [[Category: Spooner, E.]] | ||
| - | [[Category: Sun, Z | + | [[Category: Sun, Z J.]] |
[[Category: Wagner, G.]] | [[Category: Wagner, G.]] | ||
[[Category: evolution]] | [[Category: evolution]] | ||
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[[Category: ubiquitin]] | [[Category: ubiquitin]] | ||
| - | ''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 18:06:27 2008'' |
Revision as of 16:06, 21 February 2008
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Solution structure of the ubiquitin domain N-terminal to the S27a ribosomal subunit of Giardia lamblia
Overview
Encoded by a multigene family, ubiquitin is expressed in the form of three precursor proteins, two of which are fusions to the ribosomal subunits S27a and L40. Ubiquitin assists in ribosome biogenesis and also functions as a post-translational modifier after its release from S27a or L40. However, several species do not conserve the ribosomal ubiquitin domains. We report here the solution structure of a distant variant of ubiquitin, found at the N-terminus of S27a in Giardia lamblia, referred to as GlUb(S27a). Despite the considerable evolutionary distance that separates ubiquitin from GlUb(S27a), the structure of GlUb(S27a) is largely identical to that of ubiquitin. The variant domain remains attached to S27a and is part of the assembled holoribosome. Thus, conservation of tertiary structure suggests a role of this variant as a chaperone, while conservation of the primary structure--necessary for ubiquitin's function as a post-translational modifier--is no longer required. Based on these observations, we propose a model to explain the origin of the widespread ubiquitin superfold in eukaryotes.
About this Structure
2JX5 is a Single protein structure of sequence from Giardia lamblia atcc 50803. Full crystallographic information is available from OCA.
Reference
Sequence and structure evolved separately in a ribosomal ubiquitin variant., Catic A, Sun ZY, Ratner DM, Misaghi S, Spooner E, Samuelson J, Wagner G, Ploegh HL, EMBO J. 2007 Jul 25;26(14):3474-83. Epub 2007 Jun 28. PMID:17599068
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