Unknown,Transcriptomics,Genomics,Proteomics

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Bacterial antisense RNAs are mainly the product of transcriptional noise

ABSTRACT: Cis-encoded antisense RNAs (asRNAs) are widespread along bacterial transcriptomes. However, the role of the vast majority of these RNAs remains unknown, and there is an ongoing discussion as to what extent these transcripts are the result of transcriptional noise. We show, by comparative transcriptomics of 20 bacterial species and one chloroplast, that the number of asRNAs is exponentially dependent on the genomic AT content, and that expression of asRNA at low levels exerts little impact in terms of energy consumption. A transcription model simulating mRNA and asRNA production indicates that the asRNA regulatory effect is only observed above certain expression thresholds, substantially higher than physiological transcript levels. These predictions were verified experimentally by overexpressing 9 different asRNAs in M. pneumoniae. Our results suggest that most of the antisense transcripts found in bacteria are the consequence of transcriptional noise, arising at spurious promoters throughout the genome.

INSTRUMENT(S): Illumina HiSeq 2000

ORGANISM(S): Mycoplasma pneumoniae

SUBMITTER: Vernica LlorASns-Rico

PROVIDER: E-MTAB-4081 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Project description:LlorénsRico2016 - Effects of cis-Encoded antisense RNAs (asRNAs) - Case1 Three putative effects of the asRNAs were considered in this study: in case 1 , the binding of the asRNA to the corresponding mRNA induces degradation of the duplex. In case 2 (this model) the binding of the asRNA to the mRNA induces degradation of the mRNA, but not of the asRNA. In case 3, the mRNA and the asRNA bind reversibly to form a stable duplex, preventing translation of the mRNA. In all the three cases, binding to the ribosome protects the mRNA from the effect of the asRNA. This model is described in the article: Bacterial antisense RNAs are mainly the product of transcriptional noise. Lloréns-Rico V, Cano J, Kamminga T, Gil R, Latorre A, Chen WH, Bork P, Glass JI, Serrano L, Lluch-Senar M. Sci Adv 2016 Mar; 2(3): e1501363 Abstract: cis-Encoded antisense RNAs (asRNAs) are widespread along bacterial transcriptomes. However, the role of most of these RNAs remains unknown, and there is an ongoing discussion as to what extent these transcripts are the result of transcriptional noise. We show, by comparative transcriptomics of 20 bacterial species and one chloroplast, that the number of asRNAs is exponentially dependent on the genomic AT content and that expression of asRNA at low levels exerts little impact in terms of energy consumption. A transcription model simulating mRNA and asRNA production indicates that the asRNA regulatory effect is only observed above certain expression thresholds, substantially higher than physiological transcript levels. These predictions were verified experimentally by overexpressing nine different asRNAs in Mycoplasma pneumoniae. Our results suggest that most of the antisense transcripts found in bacteria are the consequence of transcriptional noise, arising at spurious promoters throughout the genome. This model is hosted on BioModels Database and identified by: MODEL1511170001. To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication for more information.

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Bacterial antisense RNAs are mainly the product of transcriptional noise

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