Rpf2p, an Evolutionarily Conserved Protein, Interacts with Ribosomal Protein L11 and Is Essential for the Processing of 27 SB Pre-rRNA to 25 S rRNA and the 60 S Ribosomal Subunit Assembly inSaccharomyces cerevisiae

ABSTRACT Ribosomal protein uS5 is an essential component of the small ribosomal subunit that is involved in subunit assembly, maintenance of translational fidelity, and the ribosome's response to the antibiotic spectinomycin. While many of the characterized uS5 mutations that affect decoding map to its interface with uS4, more recent work has shown that residues distant from the uS4-uS5 interface can also affect the decoding process. We targeted one such interface-remote area, the loop 2 region (residues 20 to 31), for mutagenesis in Escherichia. coli and generated 21 unique mutants. A majority of the loop 2 alterations confer resistance to spectinomycin and affect the fidelity of translation. However, only a minority show altered rRNA processing or ribosome biogenesis defects.

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Transcription of genes encoding trans-acting factors required for rRNA maturation/ribosomal subunit assembly is coordinately regulated with ribosomal protein genes and involves Rap1 in Saccharomyces cerevisiae

Nucleic Acids Research ◽

10.1093/nar/gkg278 ◽

2003 ◽

Vol 31 (7) ◽

pp. 1969-1973 ◽

Cited By ~ 15

Author(s):

K. Miyoshi

Keyword(s):

Saccharomyces Cerevisiae ◽

Ribosomal Protein ◽

Ribosomal Subunit ◽

Ribosomal Protein Genes ◽

Subunit Assembly ◽

Genes Encoding ◽

Rrna Maturation

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Interaction between the assembly of the ribosomal subunits: Disruption of 40S ribosomal assembly causes accumulation of extra-ribosomal 60S ribosomal protein uL18/L5

10.1101/756114 ◽

2019 ◽

Author(s):

Nusrat Rahman ◽

Md Shamsuzzaman ◽

Lasse Lindahl

Keyword(s):

Protein Synthesis ◽

Ribosomal Protein ◽

Ribosomal Subunit ◽

The Other ◽

Ribosomal Subunits ◽

Subunit Assembly ◽

Ribosomal Assembly ◽

Kinetics Of

AbstractInhibition of the synthesis of a ribosomal protein (r-protein) abrogates the assembly of its cognate subunit, while assembly of the other subunit continues. Ribosomal components that are not stably incorporated into ribosomal particles due to the disrupted assembly are rapidly degraded. The 60S protein uL18/L5 is an exception, because this protein accumulates extra-ribosomally during inhibition of 60S assembly. Since the r-proteins in each ribosomal subunit are essential only for formation of their own subunit, it would be predicted that accumulation of extra-ribosomal uL18/5 only occurs during restriction of 60S assembly, and not during abolition of 40S assembly. Contrary to this prediction, we report here that repression of 40S r-protein genes does in fact lead to accumulation of uL18/L5 does outside the ribosome due modified 60S assembly. Furthermore, the effect varies depending on which 40S ribosomal protein is repressed. We propose that disruption of early steps in the 40S subunit assembly changes the kinetics of 60S subunit assembly resulting in a buildup of extra-ribosomal uL18/L5, even though 60S formation continues. Finally, our results show that maintenance of the pool of extra-ribosomal uL18/L5 requires continual protein synthesis showing that extra-ribosomal protein is not stable, but is slowly “consumed” by incorporation into 60S subunits and/or turnover.

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PDCD2 functions as an evolutionarily conserved chaperone dedicated for the 40S ribosomal protein uS5 (RPS2)

Nucleic Acids Research ◽

10.1093/nar/gkaa1108 ◽

2020 ◽

Vol 48 (22) ◽

pp. 12900-12916

Author(s):

Anne-Marie Landry-Voyer ◽

Danny Bergeron ◽

Carlo Yague-Sanz ◽

Breac Baker ◽

Francois Bachand

Keyword(s):

Ribosomal Protein ◽

Nuclear Import ◽

Quantitative Proteomics ◽

Ribosomal Proteins ◽

Ribosomal Subunit ◽

Interaction Network ◽

Protein Protein Interaction ◽

40S Ribosomal Subunit ◽

Evolutionarily Conserved ◽

Protein Protein Interaction Network

Abstract PDCD2 is an evolutionarily conserved protein with previously characterized homologs in Drosophila (zfrp8) and budding yeast (Tsr4). Although mammalian PDCD2 is essential for cell proliferation and embryonic development, the function of PDCD2 that underlies its fundamental cellular role has remained unclear. Here, we used quantitative proteomics approaches to define the protein-protein interaction network of human PDCD2. Our data revealed that PDCD2 specifically interacts with the 40S ribosomal protein uS5 (RPS2) and that the PDCD2-uS5 complex is assembled co-translationally. Loss of PDCD2 expression leads to defects in the synthesis of the small ribosomal subunit that phenocopy a uS5 deficiency. Notably, we show that PDCD2 is important for the accumulation of soluble uS5 protein as well as its incorporation into 40S ribosomal subunit. Our findings support that the essential molecular function of PDCD2 is to act as a dedicated ribosomal protein chaperone that recognizes uS5 co-translationally in the cytoplasm and accompanies uS5 to ribosome assembly sites in the nucleus. As most dedicated ribosomal protein chaperones have been identified in yeast, our study reveals that similar mechanisms exist in human cells to assist ribosomal proteins coordinate their folding, nuclear import and assembly in pre-ribosomal particles.

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