RRC ID |
35318
|
著者 |
Chadani Y, Ono K, Ozawa S, Takahashi Y, Takai K, Nanamiya H, Tozawa Y, Kutsukake K, Abo T.
|
タイトル |
Ribosome rescue by Escherichia coli ArfA (YhdL) in the absence of trans-translation system.
|
ジャーナル |
Mol Microbiol
|
Abstract |
Although SsrA(tmRNA)-mediated trans-translation is thought to maintain the translation capacity of bacterial cells by rescuing ribosomes stalled on messenger RNA lacking an in-frame stop codon, single disruption of ssrA does not crucially hamper growth of Escherichia coli. Here, we identified YhdL (renamed ArfA for alternative ribosome-rescue factor) as a factor essential for the viability of E. coli in the absence of SsrA. The ssrA-arfA synthetic lethality was alleviated by SsrA(DD) , an SsrA variant that adds a proteolysis-refractory tag through trans-translation, indicating that ArfA-deficient cells require continued translation, rather than subsequent proteolysis of the truncated polypeptide. In accordance with this notion, depletion of SsrA in the ΔarfA background led to reduced translation of a model protein without affecting transcription, and puromycin, a codon-independent mimic of aminoacyl-tRNA, rescued the bacterial growth under such conditions. That ArfA takes over the role of SsrA was suggested by the observation that its overexpression enabled detection of the polypeptide encoded by a model non-stop mRNA, which was otherwise SsrA-tagged and degraded. In vitro, purified ArfA acted on a ribosome-nascent chain complex to resolve the peptidyl-tRNA. These results indicate that ArfA rescues the ribosome stalled at the 3' end of a non-stop mRNA without involving trans-translation.
|
巻・号 |
78(4)
|
ページ |
796-808
|
公開日 |
2010-11-1
|
DOI |
10.1111/j.1365-2958.2010.07375.x
|
PMID |
21062370
|
MeSH |
Escherichia coli / metabolism*
Escherichia coli Proteins / genetics
Escherichia coli Proteins / metabolism*
Gene Deletion
Genes, Bacterial
Genes, Essential
Protein Biosynthesis*
RNA, Bacterial / metabolism*
RNA-Binding Proteins / genetics
RNA-Binding Proteins / metabolism*
Ribosomes / metabolism*
|
IF |
3.418
|
引用数 |
85
|
WOS 分野
|
MICROBIOLOGY
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
リソース情報 |
原核生物(大腸菌) |
JW3253-KC |