Etude des mécanismes de reconnaissance du transcrit dans la terminaison de la transcription Rho-dépendante

Abstract : Transcripts at a free Rut (Rho-utilization) site from which Rho moves along the RNA in an ATP dependentfashion to catch up with and dissociate the transcription elongation complex. It is generally believed that the Rut sites are, respectively, rich and poor in Cytosines and Guanines as well as relatively poor in secondary structures. Studies at the genomic or transcriptomic scale have notrevealed any stronger consensus features or rules for predicting potential Rho-dependent termination sites. By combining biochemical and bioinformatics approaches, I have explored the mechanisms by which Rho recognizes transcripts to induce transcription termination. I have identified a complex set of sequence determinants which, taken together, have good predictive power and which I used to build the first computational model able to predict Rho-dependent termination at the scale of Escherichiacoli and Salmonella genomes. I have characterized in vitro some of these terminators, particularly in 5'UTRs, with the hope that they will be involved in conditional regulatory mechanisms. I have identified several candidates whose activity may be under the control of factors such as small non-coding RNAs(sRNA) or temperature. I have also developed a fluorogenic method to easily detect Rho-dependent termination in vitro and have begun to adapt the CLIP-seq approach to the study of the Rhodependent transcriptome in Salmonella. Collectively, my work offers new tools for the analysis and prediction of Rho-dependent termination, a better mapping of the sites of probable Rho action in E.coli and Salmonella, as well as several lines of investigation of the role of Rho in the conditional expression of bacterial genomes.
Document type :
Theses
Complete list of metadatas

Cited literature [53 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02103153
Contributor : Abes Star <>
Submitted on : Thursday, April 18, 2019 - 10:15:52 AM
Last modification on : Tuesday, May 21, 2019 - 8:56:53 PM

File

cedric-nadiras_3942_vm.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02103153, version 1

Collections

Citation

Cédric Nadiras. Etude des mécanismes de reconnaissance du transcrit dans la terminaison de la transcription Rho-dépendante. Sciences agricoles. Université d'Orléans, 2018. Français. ⟨NNT : 2018ORLE2033⟩. ⟨tel-02103153⟩

Share

Metrics

Record views

129

Files downloads

60