Biomaterial Database

Interaction between the assembly of the ribosomal subunits: Disruption of 40S ribosomal assembly causes accumulation of extra-ribosomal 60S ribosomal protein uL18/L5. 2020

Nusrat Rahman, and Md Shamsuzzaman, and Lasse Lindahl

Department of Biological Sciences, University of Maryland, Baltimore County (UMBC), Baltimore, Maryland, United States of America.

Inhibition of the synthesis of an essential 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 and this protein accumulates extra-ribosomally during inhibition of 60S assembly. Since the r-proteins in each ribosomal subunit are essential only for the formation of their cognate subunit, it would be predicted that accumulation of extra-ribosomal uL18/L5 is specific to restriction of 60S assembly and does not occur abolition of 40S assembly. Contrary to this prediction, we report here that repression of 40S r-protein genes does lead to accumulation of uL18/L5 outside of the ribosome. Furthermore, the effect varies depending on which 40S ribosomal protein is repressed. Our results also show extra-ribosomal uL18/L5 is formed during 60S assembly, not during degradation of mature cytoplasmic 60S subunits. Finally, we propose a model for the accumulation of extra-ribosomal uL18 in response to the abolition of 40S r-proteins.

UI	MeSH Term	Description	Entries
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012269	Ribosomal Proteins	Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.	Proteins, Ribosomal,Ribosomal Protein,Protein, Ribosomal
D012270	Ribosomes	Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.	Ribosome
D012335	RNA, Ribosomal	The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)	Ribosomal RNA,15S RNA,RNA, 15S
D054682	Ribosome Subunits, Small, Eukaryotic	The small subunit of the 80s ribosome of eukaryotes. It is composed of the 18S RIBOSOMAL RNA and 32 different RIBOSOMAL PROTEINS.	40S Ribosomal Subunits,40S Ribosome Subunits,Eukaryotic Small Ribosomal Subunits,Eukaryotic Small Ribosome Subunits,Ribosomal Subunits, 40S,Ribosomal Subunits, Small, Eukaryotic,Ribosome Subunits, 40S,Small Ribosomal Subunits, Eukaryotic,Small Ribosome Subunits, Eukaryotic,40S Ribosomal Subunit,40S Ribosome Subunit,Ribosomal Subunit, 40S,Ribosome Subunit, 40S,Subunit, 40S Ribosomal,Subunit, 40S Ribosome,Subunits, 40S Ribosomal,Subunits, 40S Ribosome
D054683	Ribosome Subunits, Large, Eukaryotic	The large subunit of the 80s ribosome of eukaryotes. It is composed of the 28S RIBOSOMAL RNA, the 5.8S RIBOSOMAL RNA, the 5S RIBOSOMAL RNA, and about 50 different RIBOSOMAL PROTEINS.	60S Ribosomal Subunits,60S Ribosome Subunits,Eukaryotic Large Ribosomal Subunits,Eukaryotic Large Ribosome Subunits,Large Ribosomal Subunits, Eukaryotic,Large Ribosome Subunits, Eukaryotic,Ribosomal Subunits, 60S,Ribosomal Subunits, Large, Eukaryotic,Ribosome Subunits, 60S,60S Ribosomal Subunit,60S Ribosome Subunit,Ribosomal Subunit, 60S,Ribosome Subunit, 60S,Subunit, 60S Ribosomal,Subunit, 60S Ribosome,Subunits, 60S Ribosomal,Subunits, 60S Ribosome