Ribosomal proteins are assumed to stabilize specific RNA structures and promote compact folding of the large rRNA. The conformational dynamics of the protein between the bound and unbound state play an important role in the binding process. We have studied those dynamical changes in detail for the highly conserved complex between the ribosomal protein L11 and the GTPase region of 23S rRNA. The ...

The c-Myc oncoprotein promotes cell growth by enhancing ribosomal biogenesis through upregulation of RNA polymerases I-, II-, and III-dependent transcription. Overexpression of c-Myc and aberrant ribosomal biogenesis leads to deregulated cell growth and tumorigenesis. Hence, c-Myc activity and ribosomal biogenesis must be regulated in cells. Here, we show that ribosomal protein L11, a component...

The ribosomal protein L11 binds to and suppresses the E3 ligase function of HDM2, thus activating p53. Despite being abundant as a component of the 60S large ribosomal subunit, L11 does not induce p53 under normal growth conditions. In search of mechanisms controlling L11-HDM2 interaction, we found that the induction of p53 under growth inhibitory conditions, such as low dose of actinomycin D o...

The L11 binding site is one of the most important functional sites in the ribosome. The N-terminal domain of L11 has been implicated as a "reversible switch" in facilitating the coordinated movements associated with EF-G-driven GTP hydrolysis. The reversible switch mechanism has been hypothesized to require conformational flexibility involving re-orientation and re-positioning of the two L11 do...

A newly identified class of highly thiostrepton-resistant mutants of the archaeon Halobacterium halobium carry a missense mutation at codon 18 within the gene encoding ribosomal protein L11. In the mutant proteins, a proline, conserved in archaea and bacteria, is converted to either serine or threonine. The mutations do not impair either the assembly of the mutant L11 into 70 S ribosomes in viv...

The L11 ribosomal protein operon of Escherichia coli contains the genes for L11 and L1 and is feedback regulated by the translational repressor L1. The mRNA target site for this repression is located close to the Shine-Dalgarno sequence for the first cistron, rp1K (L11). By use of a random mutagenesis procedure we have isolated and characterized a series of point mutations in the L11 leader mRN...

The ribosomal protein L11 in bacteria is posttranslationally trimethylated at multiple amino acid positions by the L11 methyltransferase PrmA, the product of the prmA gene. The role of L11 methylation in ribosome function or assembly has yet to be determined, although the deletion of Escherichia coli prmA has no apparent phenotype. We have constructed a mutant of the extreme thermophile Thermus...

Several studies have shown that ribosomal proteins (RPs) are important mediators of p53 activation in response to nucleolar disruption; however, the pathways that control this signalling function of RPs are currently unknown. We have recently shown that RPs are targets for the ubiquitin-like molecule NEDD8, and that NEDDylation protects RPs from destabilization. Here, we identify NEDD8 as a cru...