Nejvíce citovaný článek - PubMed ID 22072964
Bacteria have evolved structured RNAs that can associate with RNA polymerase (RNAP). Two of them have been known so far-6S RNA and Ms1 RNA but it is unclear if any other types of RNAs binding to RNAP exist in bacteria. To identify all RNAs interacting with RNAP and the primary σ factors, we have established and performed native RIP-seq in Bacillus subtilis, Corynebacterium glutamicum, Streptomyces coelicolor, Mycobacterium smegmatis and the pathogenic Mycobacterium tuberculosis. Besides known 6S RNAs in B. subtilis and Ms1 in M. smegmatis, we detected MTS2823, a homologue of Ms1, on RNAP in M. tuberculosis. In C. glutamicum, we discovered novel types of structured RNAs that associate with RNAP. Furthermore, we identified other species-specific RNAs including full-length mRNAs, revealing a previously unknown landscape of RNAs interacting with the bacterial transcription machinery.
- MeSH
- Bacillus subtilis genetika metabolismus MeSH
- bakteriální proteiny * metabolismus genetika MeSH
- bakteriální RNA * metabolismus genetika MeSH
- Corynebacterium glutamicum genetika metabolismus MeSH
- DNA řízené RNA-polymerasy * metabolismus genetika MeSH
- genetická transkripce MeSH
- konformace nukleové kyseliny MeSH
- Mycobacterium smegmatis genetika metabolismus enzymologie MeSH
- Mycobacterium tuberculosis genetika metabolismus MeSH
- nekódující RNA MeSH
- regulace genové exprese u bakterií MeSH
- sigma faktor * metabolismus genetika MeSH
- Streptomyces coelicolor genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 6S RNA MeSH Prohlížeč
- bakteriální proteiny * MeSH
- bakteriální RNA * MeSH
- DNA řízené RNA-polymerasy * MeSH
- nekódující RNA MeSH
- sigma faktor * MeSH
Bacteria employ small non-coding RNAs (sRNAs) to regulate gene expression. Ms1 is an sRNA that binds to the RNA polymerase (RNAP) core and affects the intracellular level of this essential enzyme. Ms1 is structurally related to 6S RNA that binds to a different form of RNAP, the holoenzyme bearing the primary sigma factor. 6S RNAs are widespread in the bacterial kingdom except for the industrially and medicinally important Actinobacteria. While Ms1 RNA was identified in Mycobacterium, it is not clear whether Ms1 RNA is present also in other Actinobacteria species. Here, using a computational search based on secondary structure similarities combined with a linguistic gene synteny approach, we identified Ms1 RNA in Streptomyces. In S. coelicolor, Ms1 RNA overlaps with the previously annotated scr3559 sRNA with an unknown function. We experimentally confirmed that Ms1 RNA/scr3559 associates with the RNAP core without the primary sigma factor HrdB in vivo. Subsequently, we applied the computational approach to other Actinobacteria and identified Ms1 RNA candidates in 824 Actinobacteria species, revealing Ms1 RNA as a widespread class of RNAP binding sRNAs, and demonstrating the ability of our multifactorial computational approach to identify weakly conserved sRNAs in evolutionarily distant genomes.
- Klíčová slova
- 6S RNA, Actinobacteria, Ms1 RNA, Mycobacterium, Streptomyces, gene synteny, sRNA,
- Publikační typ
- časopisecké články MeSH
Small RNAs (sRNAs) are molecules essential for a number of regulatory processes in the bacterial cell. Here we characterize Ms1, a sRNA that is highly expressed in Mycobacterium smegmatis during stationary phase of growth. By glycerol gradient ultracentrifugation, RNA binding assay, and RNA co-immunoprecipitation, we show that Ms1 interacts with the RNA polymerase (RNAP) core that is free of the primary sigma factor (σA) or any other σ factor. This contrasts with the situation in most other species where it is 6S RNA that interacts with RNAP and this interaction requires the presence of σA. The difference in the interaction of the two types of sRNAs (Ms1 or 6S RNA) with RNAP possibly reflects the difference in the composition of the transcriptional machinery between mycobacteria and other species. Unlike Escherichia coli, stationary phase M. smegmatis cells contain relatively few RNAP molecules in complex with σA. Thus, Ms1 represents a novel type of small RNAs interacting with RNAP.
- MeSH
- bakteriální chromozomy MeSH
- DNA řízené RNA-polymerasy metabolismus MeSH
- konformace nukleové kyseliny MeSH
- malá nekódující RNA chemie genetika metabolismus MeSH
- Mycobacterium smegmatis enzymologie genetika růst a vývoj MeSH
- Mycobacterium genetika MeSH
- sigma faktor metabolismus MeSH
- syntenie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA řízené RNA-polymerasy MeSH
- malá nekódující RNA MeSH
- sigma faktor MeSH
Understanding the control of gene expression is critical for our understanding of the relationship between genotype and phenotype. The need for reliable assessment of transcript abundance in biological samples has driven scientists to develop novel technologies such as DNA microarray and RNA-Seq to meet this demand. This review focuses on comparing the two most useful methods for whole transcriptome gene expression profiling. Microarrays are reliable and more cost effective than RNA-Seq for gene expression profiling in model organisms. RNA-Seq will eventually be used more routinely than microarray, but right now the techniques can be complementary to each other. Microarrays will not become obsolete but might be relegated to only a few uses. RNA-Seq clearly has a bright future in bioinformatic data collection.
