Article

In vivo effect of inactivation of ribosome recycling factor - fate of ribosomes after unscheduled translation downstream of open reading frame.

Department of Clinical Biochemistry, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan.
Molecular Microbiology (impact factor: 5.01). 12/2004; 54(4):1011-21. DOI:10.1111/j.1365-2958.2004.04324.x pp.1011-21
Source: PubMed

ABSTRACT The post-termination ribosomal complex is disassembled by ribosome recycling factor (RRF) and elongation factor G. Without RRF, the ribosome is not released from mRNA at the termination codon and reinitiates translation downstream. This is called unscheduled translation. Here, we show that at the non-permissive temperature of a temperature-sensitive RRF strain, RRF is lost quickly, and some ribosomes reach the 3' end of mRNA. However, instead of accumulating at the 3' end of mRNA, ribosomes are released as monosomes. Some ribosomes are transferred to transfer-messenger RNA from the 3' end of mRNA. The monosomes thus produced are able to translate synthetic homopolymer but not natural mRNA with leader and canonical initiation signal. The pellet containing ribosomes appears to be responsible for rapid but reversible inhibition of most but not all of protein synthesis in vivo closely followed by decrease of cellular RNA and DNA synthesis.

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Keywords

canonical initiation signal
 
cellular RNA
 
decrease
 
DNA synthesis
 
mRNA
 
natural mRNA
 
non-permissive temperature
 
protein synthesis
 
reinitiates translation downstream
 
responsible
 
reversible inhibition
 
ribosome
 
ribosome recycling factor
 
ribosomes
 
RRF
 
temperature-sensitive RRF strain
 
termination codon
 
transfer-messenger RNA
 
unscheduled translation
 
vivo