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PDBsum entry 1cjs
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Contents |
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* Residue conservation analysis
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References listed in PDB file
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Key reference
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Title
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Archaeal ribosomal protein l1: the structure provides new insights into RNA binding of the l1 protein family.
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Authors
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N.Nevskaya,
S.Tischenko,
R.Fedorov,
S.Al-Karadaghi,
A.Liljas,
A.Kraft,
W.Piendl,
M.Garber,
S.Nikonov.
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Ref.
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Structure, 2000,
8,
363-371.
[DOI no: ]
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PubMed id
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Abstract
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BACKGROUND: L1 is an important primary rRNA-binding protein, as well as a
translational repressor that binds mRNA. It was shown that L1 proteins from some
bacteria and archaea are functionally interchangeable within the ribosome and in
the repression of translation. The crystal structure of bacterial L1 from
Thermus thermophilus (TthL1) has previously been determined. RESULTS: We report
here the first structure of a ribosomal protein from archaea, L1 from
Methanococcus jannaschii (MjaL1). The overall shape of the two-domain molecule
differs dramatically from that of its bacterial counterpart (TthL1) because of
the different relative orientations of the domains. Two strictly conserved
regions of the amino acid sequence, each belonging to one of the domains and
positioned close to each other in the interdomain cavity of TthL1, are separated
by about 25 A in MjaL1 owing to a significant opening of the structure. These
regions are structurally highly conserved and are proposed to be the specific
RNA-binding sites. CONCLUSIONS: The unusually high RNA-binding affinity of MjaL1
might be explained by the exposure of its highly conserved regions. The open
conformation of MjaL1 is strongly stabilized by nonconserved interdomain
interactions and suggests that the closed conformations of L1 (as in TthL1) open
upon RNA binding. Comparison of the two L1 protein structures reveals a high
conformational variability of this ribosomal protein. Determination of the MjaL1
structure offers an additional variant for fitting the L1 protein into
electron-density maps of the 50S ribosomal subunit.
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Figure 7.
Figure 7. The molecular surfaces of (a) TthL1 and (b) MjaL1
coloured by electrostatic potential (red, negative; blue,
positive; white, uncharged). A well-defined region of positive
charge is seen clearly in domain II of MjaL1. (This figure was
generated using WebLab ViewerPro [29].)
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The above figure is
reprinted
by permission from Cell Press:
Structure
(2000,
8,
363-371)
copyright 2000.
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