Since the discovery of the three domains of life (Eukarya, Bacteria and Archaea), Archaea which are major player in the microbial stage, are considered of universal emphasis to study the evolutionary history of life and promising for emergence of new technologies. The focus of the emerging project of B. Clouet-d’Orval in close collaboration with local, national and international partners is to explore the “RNA metabolism in Archaea”, a new field in archaeal molecular biology research, to unravel RNA processing pathways which are of fundamental standing in biology. This research theme is integrated into the genome dynamics axis of the “Centre de Biologie Intégrative” (CBI).
One of our challenges is to shed light on central aspects of gene expression control in Archaea by addressing the role of two major phylogenetically conserved archaeal β-CASP ribonucleases, aCFSF1 and aRNase J. This includes identifying and studying their mechanism of action and relating these enzymes to the decay and processing of RNAs. First hints towards identifying those pathways came from our recent phylogenomic studies and biochemical characterizations of aCPSF1 and aRNase J, which are orthologs of eukaryal CPSF73 and bacterial RNase J, respectively. This shows that Archaea might possess a composite RNA processing system sharing both eukaryal and bacterial features and highlights the advantage of the archaeal model to gain further mechanistic and evolutionary information on RNA processing pathways.
Furthermore using a combination of in silico and experimental approaches, we identified and characterized novel P. abyssi ncRNAs. The majority of them are subjected to processing events and two of which have features similar to known bacterial riboswitches. We proposed a revised annotation of CRISPR loci in P. abyssi and we reviewed available information on genetic elements infecting the Thermococcales and on the multiple CRISPR systems found in the Pyrococcales.
B. Clouet-d’Orval is a member board of national consortium “Groupement de Recherche -GDR 3635- Archaea: Biodiversité, Origine, Processus cellulaires fondamentaux, biotechnologies” (http://lbbe-dmz.univ-lyon1.fr/spip_archaea/) and leads the RNA axis.
RNA processing, β-CASP ribonucleases, non coding RNAs, CRISPR systems, Archaea