1cjs
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CRYSTAL STRUCTURE OF RIBOSOMAL PROTEIN L1 FROM METHANOCOCCUS JANNASCHII
OverviewOverview
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.
About this StructureAbout this Structure
1CJS is a Single protein structure of sequence from Methanocaldococcus jannaschii. Full crystallographic information is available from OCA.
ReferenceReference
Archaeal ribosomal protein L1: the structure provides new insights into RNA binding of the L1 protein family., Nevskaya N, Tischenko S, Fedorov R, Al-Karadaghi S, Liljas A, Kraft A, Piendl W, Garber M, Nikonov S, Structure. 2000 Apr 15;8(4):363-71. PMID:10801481
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