Instability of sensory histidine kinase mRNAs in Escherichia coli.
BACKGROUND
Regulating mRNA stability is one of the essential mechanisms in gene expression. In order to identify genes from Escherichia coli whole genome whose expression is effectively modulated during the process of mRNA decay, we previously performed differential display-PCR as the first step. In the screening, it was suggested that two mRNAs from the histidine kinase genes, narX and yojN, in a two-component signal transduction system, were extremely unstable. In this study we analysed the stability of sensory kinase mRNAs, e.g. arcB, barA, rcsC, narQ, narX and evgS mRNA.


RESULTS
The cellular level of the histidine kinase mRNAs was very low and the mRNAs were rapidly degraded in wild-type cells cultured at 37 degrees C in LB medium. Additional experiments using RNase E deficient cells indicated that the mRNAs existed abundantly and expressed a prolonged half-life in the cells. Monocistronic transcripts of the cognate response regulator genes, arcA, rcsB, narP and narL have a half-life of 1.5-3.4 min.


CONCLUSIONS
mRNAs of the six histidine kinase genes in E. coli are synthesized efficiently, but rapidly degraded in wild-type cells.
Aiso
Toshiko
T
Department of Molecular Biology, School of Health Sciences, Kyorin University, 476 Miyashita, Hachioji, Tokyo 192-8508, Japan.
Ohki
Reiko
R
D004926:Escherichia coli / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D000071677:Histidine Kinase; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
D012333:RNA, Messenger; D011494:Protein Kinases; D000071677:Histidine Kinase