The diversity of RNAs inside living cells is amazing. We have known of the more “classic” RNA species: mRNA, tRNA, rRNA, snRNA and snoRNA for some time now, but in a steady stream new types of molecules are being described as it is becoming clear that most of the genomic information of cells ends up in RNA. To deal with the enormous load of resulting RNA processing and degradation reactions, cells need adequate and efficient molecular machines. The RNA exosome is arising as a major facilitator to this effect. Structural and functional data gathered over the last decade have illustrated the biochemical importance of this multimeric complex and its many co-factors, revealing its enormous regulatory power. By gathering some of the most prominent researchers in the exosome field, it is the aim of this volume to introduce this fascinating protein complex as well as to give a timely and rich account of its many functions. The exosome was discovered more than a decade ago by Phil Mitchell and David Tollervey by its ability to trim the 3’end of yeast, S. cerevisiae, 5. 8S rRNA. In a historic account they laid out the events surrounding this identification and the subsequent birth of the research field. In the chapter by Kurt Januszyk and Christopher Lima the structural organization of eukaryotic exosomes and their evolutionary counterparts in bacteria and archaea are discussed in large part through presentation of structures.
Discusses structural organization of eukaryotic exosomes and their evolutionary counterparts in bacteria and archaea Presents recently discovered roles in the elimination of transcriptional noise and in heterochromatization Gives a historic perspective on the parallel discovery of the exosome and discusses the occurrence of autoantibodies to exosome components in autoimmune diseases and the connection of the exosome with cancer
Finding The Exosome.- Structural Components And Architectures Of Rna Exosomes.- The Archaeal Exosome.- The Exosomes Of Trypanosomes And Other Protists.- The Exosome And 3??5? Rna Degradation In Plants.- Catalytic Properties Of The Eukaryotic Exosome.- Functions Of The Cytopl Asmic Exosome.- Rrp6, Rrp477 And Cofacto Rs Of The Nuclear Exosome.- The Exosome And Heterochromatin: Multilevel Regulation Of Gene Silencing.- Control Of Cryptic Transcription In Eukaryotes.- The Human Exosome And Disease