Expression of both Bacillus subtilis threonyl-tRNA synthetase genes is autogenously regulated.
AUTOR(ES)
Gendron, N
RESUMO
The "housekeeping" threonyl-tRNA synthetase gene (thrS) of Bacillus subtilis is shown to be transcribed in vivo and in vitro from a single promoter. In vitro, 85% of all messages transcribed from the thrS promoter are terminated at a strong factor-independent terminator localized upstream of the thrS Shine-Dalgarno sequence, within the 305-nucleotide-long leader region. Overexpression of thrS represses transcriptional and translational thrS-lacZ fusions to a similar extent, suggesting that thrS is autoregulated at the transcriptional level. We show that autogenous control does not act at the level of transcription initiation but involves antitermination of the transcription mechanism. thrZ, the second threonyl-tRNA synthetase gene, is also autogenously regulated. However, the ability of the ThrS synthetase to repress thrS as well as thrZ expression is much greater than that of the ThrZ synthetase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=205072Documentos Relacionados
- Independent genes for two threonyl-tRNA synthetases in Bacillus subtilis.
- Co-ordinate expression of the two threonyl-tRNA synthetase genes in Bacillus subtilis: control by transcriptional antitermination involving a conserved regulatory sequence.
- The expression of E.coli threonyl-tRNA synthetase is regulated at the translational level by symmetrical operator-repressor interactions.
- Escherichia coli Mutants Overproducing Phenylalanyl- and Threonyl-tRNA Synthetase
- Identity elements of tRNA(Thr) towards Saccharomyces cerevisiae threonyl-tRNA synthetase.
