Study Of The Transcriptional Regulation Of SRNA EsrE In Escherichia Coli

In Escherichia coli,sRNA EsrE is essential for aerobic growth,colony size,antibiotic sensitivity and other cellular process such as Q8 biosynthesis.Our previous studies had done some research on the transcriptional regulation of sRNA EsrE and several cis-regulatory elements upstream of esrE promoter were identified.Also,we screened and identified 54 potential transcriptional regulatory proteins.In this work,we focused on confirming the role of the potential regulatory proteins in the transcription of EsrE and understanding the regulatory mechanisms.We constructed the dual-plasmid reporter system based on former work and confirmed the regulatory function of potential regulatory factors with this system.Our date showed both FabZ and RpoH regulate the transcription of EsrE.FabZ,?-hydroxyacyl-ACP dehydratases in fatty acid synthesis system,was found that negatively regulate EsrE transcription with the dual-plasmid reporter analysis.However,FabZ could not bind the promoter S1V3 in vitro through electrophoretic mobility shift assay(EMSA).These suggested FabZ regulates EsrE transcription via an unknown way.RpoH,RNA polymerase ? unit,showed the ability of up-regulating EsrE transcription in vivo.In EMSA,RpoH bound the S1V3 fragment with the existence of RNA polymerase core enzyme.These results showed that RpoH regulates EsrE transcription.Based on the evidence that RpoH plays a key role in bacterial under heat shock response.We next explored the transcription of EsrE under heat shock.The ?-galactosidase activity assays and RT-qPCR proved the increasing transcription level of EsrE with high temperature.Taken together,our results found the ? factor involved in transcription of sRNA EsrE and the transcription of EsrE can be affected under heat shock responses.Our results shed light on the regulation of sRNA EsrE and uncover yet another unknown regulatory element involved in its regulation.