An Overview of Ribonuclease Repertoire and RNA Processing Pathways in Archaea

Abstract

RNA processing plays a crucial role in post-transcriptional regulation of gene expression. Work conducted in Bacteria and Eukarya has defined the predominant mRNA maturation and decay pathways, as well as enzymes and cofactors responsible for these processes. In contrast, our knowledge of the mechanisms controlling RNA quality and processing in Archaea is more fragmentary. In essence, the major actors of RNA processing are ribonucleases acting in cleaving or trimming RNA molecules according to their nature and fate, making these enzymes fascinating and important players to study. More than 30 families of ribonucleases have been described in Bacteria and Eukarya, while only few have been identified in Archaea. This chapter is focused on the major ribonucleases in Archaea. After an overview of archaeal cellular RNA biotypes, we present synthetic up-to-date repertoire of the archaeal ribonuclease families as well as our state of knowledge on their roles in dedicated RNA processing pathways. In addition to this general description of archaeal RNA processing actors, specific pathways involved in processing of rRNAs, tRNAs, crRNAs and C/D sRNAs are detailed in other chapters.