Domain II of Thermus thermophilus Ribosomal Protein L1 Hinders Recognition of Its mRNA (original) (raw)

Crystal structure of the RNA binding ribosomal protein L1 from Thermus thermophilus

The EMBO journal, 1996

L1 has a dual function as a ribosomal protein binding rRNA and as a translational repressor binding mRNA. The crystal structure of L1 from Thermus thermophilus has been determined at 1.85 angstroms resolution. The protein is composed of two domains with the N- and C-termini in domain I. The eight N-terminal residues are very flexible, as the quality of electron density map shows. Proteolysis experiments have shown that the N-terminal tail is accessible and important for 23S rRNA binding. Most of the conserved amino acids are situated at the interface between the two domains. They probably form the specific RNA binding site of L1. Limited non-covalent contacts between the domains indicate an unstable domain interaction in the present conformation. Domain flexibility and RNA binding by induced fit seems plausible.

New Insights into the Interaction of Ribosomal Protein L1 with RNA

Journal of Molecular Biology, 2006

The RNA-binding ability of ribosomal protein L1 is of profound interest, since L1 has a dual function as a ribosomal structural protein that binds rRNA and as a translational repressor that binds its own mRNA. Here, we report the crystal structure at 2.6 Å resolution of ribosomal protein L1 from the bacterium Thermus thermophilus in complex with a 38 nt fragment of L1 mRNA from Methanoccocus vannielii. The conformation of RNA-bound T. thermophilus L1 differs dramatically from that of the isolated protein.

Domain I of ribosomal protein L1 is sufficient for specific RNA binding

Nucleic Acids Research, 2007

Ribosomal protein L1 has a dual function as a ribosomal protein binding 23S rRNA and as a translational repressor binding its mRNA. L1 is a two-domain protein with N-and C-termini located in domain I. Earlier it was shown that L1 interacts with the same targets on both rRNA and mRNA mainly through domain I. We have suggested that domain I is necessary and sufficient for specific RNA-binding by L1. To test this hypothesis, a truncation mutant of L1 from Thermus thermophilus, representing domain I, was constructed by deletion of the central part of the L1 sequence, which corresponds to domain II. It was shown that the isolated domain I forms stable complexes with specific fragments of both rRNA and mRNA. The crystal structure of the isolated domain I was determined and compared with the structure of this domain within the intact protein L1. This comparison revealed a close similarity of both structures. Our results confirm our suggestion that in protein L1 its domain I alone is sufficient for specific RNA binding, whereas domain II stabilizes the L1-rRNA complex.

Structure of the ribosomal protein L1–mRNA complex at 2.1 Å resolution: common features of crystal packing of L1–RNA complexes

Acta Crystallographica Section D Biological Crystallography, 2006

The crystal structure of a hybrid complex between the bacterial ribosomal protein L1 from Thermus thermophilus and a Methanococcus vannielii mRNA fragment containing an L1-binding site was determined at 2.1 Å resolution. It was found that all polar atoms involved in conserved protein-RNA hydrogen bonds have high values of density in the electron-density map and that their hydrogen-bonding capacity is fully realised through interactions with protein atoms, water molecules and K + ions. Intermolecular contacts were thoroughly analyzed in the present crystals and in crystals of previously determined L1-RNA complexes. It was shown that extension of the RNA helices providing canonical helix stacking between open-open or open-closed ends of RNA fragments is a common feature of these and all known crystals of complexes between ribosomal proteins and RNAs. In addition, the overwhelming majority of complexes between ribosomal proteins and RNA molecules display crystal contacts formed by the central parts of the RNA fragments. These contacts are often very extensive and strong and it is proposed that they are formed in the saturated solution prior to crystal formation.

Studying the Properties of Domain I of the Ribosomal Protein L1: Incorporation into Ribosome and Regulation of the L1 Operon Expression

The protein journal, 2015

L1 is a conserved protein of the large ribosomal subunit. This protein binds strongly to the specific region of the high molecular weight rRNA of the large ribosomal subunit, thus forming a conserved flexible structural element-the L1 stalk. L1 protein also regulates translation of the operon that comprises its own gene. Crystallographic data suggest that L1 interacts with RNA mainly by means of its domain I. We show here for the first time that the isolated domain I of the bacterial protein L1 of Thermus thermophilus and Escherichia coli is able to incorporate in vivo into the E. coli ribosome. Furthermore, domain I of T. thermophilus L1 can regulate expression of the L1 gene operon of Archaea in the coupled transcription-translation system in vitro, as well as the intact protein. We have identified the structural elements of domain I of the L1 protein that may be responsible for its regulatory properties.

Crystal structure of ribosomal protein S8 from Thermus thermophilus reveals a high degree of structural conservation of a specific RNA binding site

Journal of Molecular Biology, 1998

S8 is one of the core ribosomal proteins. It binds to 16 S RNA with high af®nity and independently of other ribosomal proteins. It also acts as a translational repressor in Escherichia coli by binding to its own mRNA. The structure of Thermus thermophilus S8 has been determined by the method of multiple isomorphous replacement at 2.9 A Ê resolution and re®ned to a crystallographic R-factor of 16.2% (R free 27.5%). The two domains of the structure have an a/b fold and are connected by a long protruding loop. The two molecules in the asymmetric unit of the crystal interact through an extensive hydrophobic core and form a tightly associated dimer, while symmetry-related molecules form a joint b-sheet of mixed type. This type of protein± protein interaction could be realized within the ribosomal assembly. A comparison of the structures of T. thermophilus and Bacillus stearothermophilus S8 shows that the interdomain loop is eight residues longer in the former and reveals high structural conservation of an extensive region, located in the C-terminal domain. From mutational studies this region was proposed earlier to be involved in speci®c interaction with RNA. On the basis of these data and on the comparison of the two structures of S8, it is proposed that the threedimensional structure of speci®c RNA binding sites in ribosomal proteins is highly conserved among different species. Abbreviations used: r.m.s., root mean square; NMR, nuclear magnetic resonance; MIR, multiple isomorphous replacement.

Disruption of shape complementarity in the ribosomal protein L1-RNA contact region does not hinder specific recognition of the RNA target site

Journal of Molecular Recognition, 2011

The formation of a specific and stable complex between two (macro)molecules implies complementary contact surface regions. We used ribosomal protein L1, which specifically binds a target site on 23S rRNA, to study the influence of surface modifications on the proteinSRNA affinity. The threonine residue in the universally conserved triad ThrSMetSGly significant for RNA recognition and binding was substituted by phenylalanine, valine and alanine, respectively. The crystal structure of the mutant Thr217Val of the isolated domain I of L1 from Thermus thermophilus (TthL1) was determined. This structure and that of two other mutants, which had been determined earlier, were analysed and compared with the structure of the wild type L1 proteins. The influence of structural changes in the mutant L1 proteins on their affinity for the specific 23S rRNA fragment was tested by kinetic experiments using surface plasmon resonance (SPR) biosensor analysis. Association rate constants undergo minor changes, whereas dissociation rate constants displayed significantly higher values in comparison with that for the wild type protein. The analysed L1 mutants recognize the specific RNA target site, but the mutant L1S23S rRNA complexes are less stable compared to the wild type complexes.

Thermodynamics of protein-RNA recognition in a highly conserved region of the large-subunit ribosomal RNA

Biochemistry, 1989

Ribosomal protein L11 from Escherichia coli specifically binds to a highly conserved region of 23s ribosomal RNA. The thermodynamics of forming a complex between this protein and several different r R N A fragments have been investigated, by use of a nitrocellulose filter binding assay. A 57-nucleotide region of the R N A (C1052-U1108) contains all the protein recognition features, and an R N A fragment containing this region binds L11 103-104-fold more tightly than tRNA. Binding constants are on the order

Structural analysis of interdomain mobility in ribosomal L1 proteins

Acta Crystallographica Section D Biological Crystallography, 2011

The crystal structure of a hybrid complex between the bacterial ribosomal protein L1 from Thermus thermophilus and a Methanococcus vannielii mRNA fragment containing an L1-binding site was determined at 2.1 Å resolution. It was found that all polar atoms involved in conserved protein-RNA hydrogen bonds have high values of density in the electron-density map and that their hydrogen-bonding capacity is fully realised through interactions with protein atoms, water molecules and K + ions. Intermolecular contacts were thoroughly analyzed in the present crystals and in crystals of previously determined L1-RNA complexes. It was shown that extension of the RNA helices providing canonical helix stacking between open-open or open-closed ends of RNA fragments is a common feature of these and all known crystals of complexes between ribosomal proteins and RNAs. In addition, the overwhelming majority of complexes between ribosomal proteins and RNA molecules display crystal contacts formed by the central parts of the RNA fragments. These contacts are often very extensive and strong and it is proposed that they are formed in the saturated solution prior to crystal formation.