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Sigma regulatory network in Rhodococcus erythropolis CCM2595
Václav Štěpánek1, Hana Dostálová1, Tobias Busche2
1Institute of Microbiology of the CAS, v.v.i., Videňská 1083, CZ-14220 Prague 4, Czech Republic.
FEMS Microbiology Letters
|February 15, 2022
Summary
Researchers identified promoters controlling sigma factor genes in Rhodococcus erythropolis. This study reveals how these key regulators are controlled, aiding in understanding bacterial gene expression.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Sigma factors are crucial for RNA polymerase function and gene regulation in bacteria.
- Understanding promoter activity is key to deciphering transcriptional networks.
Purpose of the Study:
- To identify and classify promoters driving sigma factor gene expression in Rhodococcus erythropolis CCM2595.
- To elucidate the regulatory network governing sigma factor activity.
Main Methods:
- 5'-end-specific RNA sequencing to detect transcriptional start sites (TSSs).
- Identification of promoter -35 and -10 elements.
- In vivo and in vitro assays to demonstrate promoter regulation by sigma factors.
Main Results:
- Promoters for sigA, sigB, sigD, sigE, sigG, sigH, sigJ, and sigK genes were identified.
- Promoter sequences showed similarity to those in Corynebacterium glutamicum and Mycobacterium tuberculosis.
- Extracytoplasmic function (ECF) sigma factor genes are also regulated by additional housekeeping promoters.
Conclusions:
- A model of the basic sigma transcriptional regulatory network in R. erythropolis was developed.
- The study provides insights into the complex regulation of sigma factors in this bacterium.
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