How to reach us:
Université de Sherbrooke
Faculté des Sciences
Département de biologie
2500, boul. de l'Université
Sherbrooke Québec J1K 2R1
Canada
Office:
Room D8-3064
Telephone:
(819) 821-8000, ext: 65011
Fax:
(819) 821-8049
Lab telephone:
(819) 821-8000, ext: 65413
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Daniel Lafontaine Professor, Chercheur-Boursier Senior FRSQ Adjunct professor, Université du Québec à Montréal (2002-2003) EMBO Post-doctoral Fellow, University of Dundee (UK, 1999-2002) daniel.lafontaine@usherbrooke.ca |
Member of the following organizations:
• Centre de recherche de la biologie de l'ARN
• Institut de Pharmacologie de Sherbrooke
• Centre de recherche clinique Étienne-Le Bel
Positions
Positions are available for postdocs, MSc and PhD students.
Research interests
Numerous regulatory mechanisms are known to control gene expression in response to cellular changes. Most well-characterized among these ones are the mechanisms controlling transcription, translation and mRNA stability. Within the past several years, discoveries have revealed that regulatory RNA structures are often used for transcriptional control of essential genes in bacteria and eukaryotes. Riboswitches are untranslated cis-acting mRNA elements that directly bind cellular metabolites and alter the expression of downstream genes that are almost always associated with biosynthesis or transport of a target metabolite. These RNA switches function in absence of protein cofactors and are essentially metabolite sensors using feedback control mechanisms to appropriately modulate the associated metabolite biosynthetic pathway(s). More than 2% of the genes in certain bacteria are riboswitch regulated where many are expected to be essential under most growth conditions; interference with riboswitch function is thus predicted to result in dramatic destabilization of vital metabolic pathways. It is therefore likely that small compounds can serve as antimicrobial drugs by targeting crucial bacterial riboswitches.
In our laboratory, we are studying how metabolites are used by riboswitches to perform their vital biological function. A wide array of techniques is used to monitor the cellular activity of riboswitches and their associated mechanism(s). In addition, we are interested to understand how the folding of RNA is involved in the riboswitch regulation process. Here, given the inherent dynamic nature of riboswitches, we are using Fluorescence Resonance Energy Transfer (FRET) which is one of the most powerful techniques to study the ligand binding-induced RNA folding of riboswitches. We would also like to use lessons learned to develop novel genetic control elements.
In the news
 | We have presented our research during the TEDxUdeS 2012 event. More information here. |
 | Our research concerning antibiotic development has been mentioned in the Innovation 2011 magazine. More information here. |
 | Our research has recently been honored during the "Gala d'excellence 2011 de la recherche médicale du CHUS". More information here. |
 | We have received from Québec Science the prize "Découverte de l'année 2010" which was awarded by the public. You can read the news here. |
 | Our research on the antibiotic design was selected by Québec Science as part of the 10 best discoveries of the year 2010. You can read the article here. |
 | Our research has been highlighted in a documentary by Le Code Chastenay in November 2010. You can see it here (in french). |
 | One of our papers has been published in Chemistry and Biology and we have made the cover page. The abstract of the paper is available on the NCBI. |
 | The Courrier des Sciences has published an article that talks about our research (in french) Moreover, our research perceived by the humoristic cartoon Le clin d'oeil du mois made by the biologist Benoît Leblanc. |
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Recent publications:
• A new telomerase RNA element that is critical for telomere elongation.
• Fluorescence monitoring of riboswitch transcription regulation using a dual molecular beacon assay.
• Regulatory RNAs and target mRNA decay in prokaryotes.
• Single-molecule denaturation of riboswitches.
• Experimental treatment of Staphylococcus aureus bovine intramammary infection using a guanine riboswitch ligand analog.
• Dual-acting riboswitch control of translation initiation and mRNA decay.
• Folding of the SAM-I riboswitch: A tale with a twist.
• Constitutive regulatory activity of an evolutionary-excluded riboswitch variant.
• New insights into riboswitch regulation mechanisms.
• Molecular insights into the ligand-controlled organization of the SAM-I riboswitch.
• Comparative study between transcriptionally- and translationally-acting adenine riboswitches reveals key differences in riboswitch regulatory mechanisms.
• Folding of the lysine riboswitch: importance of peripheral elements for transcriptional regulation.
• Novel riboswitch ligand analogs as selective inhibitors of guanine-related metabolic pathways.
• Therapeutic applications of ribozymes and riboswitches.
• Small RNA-mediated regulation at the level of transcript stability.
• Riboswitch structure: an internal residue mimicking the purine ligand.
• Functional Studies of DNA-Protein Interactions Using FRET Techniques.
• Molecular Basis of RNA-Mediated Gene Regulation on the Adenine Riboswitch by Single-Molecule Approaches.
• Application of Fluorescence Measurements for Characterization of Riboswitch-Ligand Interactions.
• Riboswitches: Ancient and Promising Genetic Regulators.
• Natural Functional Nucleic Acids: Ribozymes and Riboswitches.
• Folding of the SAM Aptamer is Determined by the Formation of a K-turn-dependent Pseudoknot.
• Ligand recognition determinants of guanine riboswitches.
• A loop loop interaction and a K-turn motif located in the lysine aptamer domain are important for the riboswitch gene regulation control.
• Core requirements of the adenine riboswitch aptamer for ligand binding.
• [The adenine riboswitch: a new gene regulation mechanism]
• Folding of the adenine riboswitch.
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