RNA-seq for identifying toxin MazF and MqsR cleavage sites in toxin expression and subsequent recovery cultures of Escherichia coli (mRNA and ncRNA excluding rRNA)
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ABSTRACT:
PROVIDER: PRJEB27677 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| ERR2686030_1.fastq.gz | Fastqsanger.gz | |||
| ERR2686030_2.fastq.gz | Fastqsanger.gz | |||
| ERR2686031_1.fastq.gz | Fastqsanger.gz | |||
| ERR2686031_2.fastq.gz | Fastqsanger.gz | |||
| ERR2686032_1.fastq.gz | Fastqsanger.gz |
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Project description:Bacterial toxin-antitoxin systems are thought to help bacteria to reduce their metabolism in various stressful conditions. Many toxins of the bacterial toxin-antitoxin systems are ribonucleases. Such toxins have been mostly viewed as degraders of mRNA, however recently it was demonstrated that they are also capable of cleaving non-coding RNA. MazF toxin is also hypothesized to reprogram E. colis translational machinery. Current cDNA libraries are part of a project which aims to identify the major RNA cleavage sites (in mRNA, rRNA and regulatory non-coding RNA) of MazF and MqsR toxins in E. coli. We wanted to elaborate on the roles of MazF and MqsR in E. coli: is MazF really involved in reprogramming the translational machinery or is MazF, along with MqsR, just a robust cleaver of RNA? We extracted total RNA from cultures where the expression of MazF or MqsR was induced for 2h and from cultures that had been recovering from toxin production for 30 minutes; RNA from log phase culture was used as the control. We used strand specific random primed paired end RNA sequencing data to locate the major cleavage sites. To map the cleavage sites, we counted 5’ end stacks of forward reads in each genomic position and compared them with total coverage. MazF and MqsR cleave at specific recognition sequences, ˇACA and GˇC respectively, which allowed us to eliminate the false positives. One of our initial aims was also to look for irregular RNA ligation events following toxin expression, thus we used long, 300 base reads in sequencing.
2018-10-11 | E-MTAB-6993 | biostudies-arrayexpress
Project description:Bacterial toxin-antitoxin systems help bacteria to reduce their metabolism in various stressful conditions and also play a part in generating antibiotic tolerant bacterial subpopulation called persisters. Many toxins of the bacterial toxin-antitoxin systems are ribonucleases. Such toxins have been mostly viewed as degraders of mRNA, however recently it was demonstrated that they are also capable of cleaving non-coding RNA. Current libraries are a part of a project which aims to identify the major RNA cleavage sites (in mRNA, rRNA and regulatory non-coding RNA) of MazF and MqsR toxins in E. coli. We were also interested in the activity of promoters during toxin overexpression. We used a targeted RNA-sequencing approach that allowed us to map the distinct 5- and 3-ends of toxin-cleaved RNA and also the beginnings of transcripts. We extracted total RNA from cultures where the expression of MazF or MqsR was induced; RNA from log phase culture was used as the control. In addition, RNA extracted from stationary phase culture was used to test for the possible toxin cleavage in natural stress conditions. The cleaved RNA is rapidly recycled making it possible that we miss important cleavage sites due to RNA degradation during the prolonged stationary phase. Therefore, in addition to wt E. coli we also used stationary phase RNA from exoribonuclease deficient strain where RNA cleavage products accumulate. Identification of the 5 ends is based on ligation of RNA adapters to the cellular RNA molecules, which requires 5 -monophosphates. Mapping of the 3 -ends is based on poly(A) tailing of RNA, which requires 3 -OH groups. Transcription initiation, ordinary cellular RNases, and toxin endonucleases all produce different types of RNA ends. These can be enzymatically converted to 5 -phosphates and 3 -OHs, which allows one to separately quantify the RNA ends produced by each of these processes from a single biological sample. Briefly, (i) primary transcripts have 5 -triphosphate ends that can be converted to monophosphate by Tobacco Acid Pyrophosphatase (TAP), and 3 -hydroxyl ends that can be directly polyadenylated by poly(A) polymerase. (ii) Most cellular RNases (excluding RNase I and the toxins) produce 5 -monophosphates and 3 -hydroxyls, which are directly usable for ligation/polyadenylation. (iii) RNase I, MazF, and several other toxins produce 5 -hydroxyl ends that need to be phosphorylated by T4 Polynucleotide Kinase (PNK) prior to ligation, and 2,3 -cyclic phosphates that need to be dephosphorylated and converted to 3 -hydroxyls, also by T4 PNK. In short, for each of our RNA samples three 5 end and two 3 end libraries were made. The PNK treated libraries contain reads mapping specifically to 5- or 3-ends left by toxin (or RNaseI) cleavage and TAP treated libraries have extra reads mapping to beginnings of the transcripts.
2016-11-30 | E-MTAB-4204 | biostudies-arrayexpress
Project description:A crucial bacterial strategy to avoid killing by antibiotics is to enter a growth arrested state, yet the molecular mechanisms behind this process remain elusive. The conditional overexpression of MazF, the endoribonuclease toxin of the MazEF toxin-antitoxin system in Staphylococcus aureus, is one approach to induce bacterial growth arrest, but its targets remain largely unknown. We used overexpression of MazF and high-throughput sequence analysis following the exact mapping of non-phosphorylated transcriptome ends (nEMOTE) technique to reveal in vivo toxin cleavage sites on a global scale. We obtained a catalogue of MazF cleavage sites and unearthed an extended MazF cleavage specificity that goes beyond the previously reported one. We correlated transcript cleavage and abundance in a global transcriptomic profiling during mazF overexpression. We observed that MazF affects RNA molecules involved in ribosome biogenesis, cell wall synthesis, cell division and RNA turover and thus deliver a plausible explanation for how mazF overexpression induces stasis. We hypothesize that autoregulation of MazF occurs by directly modulating the MazEF operon, such as the rsbUVW genes that regulate the alternative SigB, including an observed cleavage site on the MazF mRNA that would ultimately play a role in entry and exit from bacterial stasis.
2020-07-10 | GSE141855 | GEO
Project description:Bacterial antibiotic resistance is as a serious health problem. Antibiotic resistance appears either because of mutations or as a result of a bacteria dormant state without heritable genetic change. This non-growing state allows bacteria to survive antibiotic treatment. The mechanisms of entrance to the bacterial dormant state are unknown. It has been suggested that toxin-antitoxin systems (TASs) are possible controlling factors for cell dormancy. In Staphylococcus aureus, the role of TASs genome-wide and their link to the dormancy induction mechanisms has not been investigated in detail. In this study, we analyzed the role of MazF toxin on transcriptome, translatome and proteome of S. aureus using RNA-Seq, Ribo-Seq and quantitative proteomics. We characterized the correlation between transcription, translation, and protein levels, and demonstrated that the MazF endonuclease decreases translation directly by cleaving mRNA, and indirectly, by decreasing translation factors and by promoting ribosome hibernation. Thus, MazF represses transcription and translation of many genes rather than a particular set of genes. Nevertheless, several specific pathways affected by MazF were identified: we demonstrated that cell wall thickness is increased and cell division is decreased upon MazF induction. MazF cleaves mRNA in vivo, creating stop-less transcripts and stalled ribosomes. These stalled ribosomes are rescued by SsrA-system, which is activated upon MazF induction. Finally, we described the overall impact of MazF on S. aureus metabolism, and propose one of the mechanisms by which MazF may induce bacterial dormancy.
2020-12-28 | GSE155036 | GEO
Project description:Escherichia coli (E. coli) mazEF is an extensively studied stress-induced toxin-antitoxin (TA) system. The toxin MazF is an endoribonuclease that cleaves RNAs at ACA sites. Thereby, under stress the induced MazF generates a Stress induced Translation Machinery (STM), composed of MazF processed mRNAs and selective ribosomes that specifically translate the processed mRNAs. Here we performed a proteomic analysis of all the E. coli stress-induced proteins that are mediated through chromosomally borne mazF gene . We show that the mRNAs of almost all of them is characterized by the presence of an ACA site up to 100 nucleotides upstream to the AUG initiator. Thereby, under stressful conditions the induced MazF is processing mRNAs that are translated by STM. Furthermore, the presence of the ACA site far enough upstream (up to 100 nucleotides) to the AUG initiator may still permit translation by the canonical translation machinery. Thus, such dual translation mechanisms, enable under stress also to prepare proteins for immediate functions while coming back to normal growth conditions.
2019-02-25 | PXD010101 | Pride
Project description:Differential RNA-seq for identifying toxin MazF and MqsR cleavage sites, beginning of transcripts and stationary phase cleavage sites in Escherichia coli (mRNA, rRNA and other ncRNA)
| PRJEB12329 | ENA
Project description:To help elucidate the effect of MazF-mt9 (Rv2063A) toxin expression on translation, we generated proteomic profiles of Mycobacterium tuberculosis H37Rv cells ectopically expressing MazF-mt9
2018-10-26 | MSV000083074 | MassIVE
Project description:To help elucidate the effect of MazF-mt9 (Rv2063A) toxin expression on translation, we generated proteomic profiles of newly synthesized proteins (labeled with Azidohomoalanine and captured with an alkyne resin) in mycobacterial cells ectopically expressing MazF-mt9
2019-04-08 | MSV000083670 | MassIVE
Project description:Synthetic circuits embedded in host-cells compete with cellular processes for limited intracellular resources. We show how funneling of cellular resources, after global transcriptome degradation by the sequence-dependent endoribonuclease MazF, to a synthetic circuit can increase production. Target genes are protected from MazF activity by recoding the gene sequence to eliminate recognition sites, while preserving the amino acid sequence. The expression of a protected fluorescent reporter and flux of a high-value metabolite are significantly enhanced using this genome-scale control strategy. Proteomics measurements discover a host factor in need of protection to improve resource redistribution activity. A computational model demonstrates that the MazF mRNA-decay feedback loop enables proportional control of MazF in an optimal operating regime. Transcriptional profiling of MazF-induced cells elucidates the dynamic shifts in transcript abundance and discovers regulatory design elements. Together, our results suggest that manipulation of cellular resource allocation is a key control parameter for synthetic circuit design.
2017-04-15 | GSE94998 | GEO
Project description:MazF toxin causes alterations in Staphylococcus aureus transcriptome, translatome and proteome that underlie bacterial dormancy
| PRJNA648316 | ENA