The 23S Ribosomal RNA From Pyrococcus furiosus Is Circularly Permuted

• Main Authors: Ulf Birkedal, Bertrand Beckert, Daniel N. Wilson, Henrik Nielsen
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2020-12-01
• Series: Frontiers in Microbiology
• Subjects: archaea; Pyrococcus; ribosomal RNA processing; circular permutation; fragmented ribosomal RNA
• Online Access: https://www.frontiersin.org/articles/10.3389/fmicb.2020.582022/full

Synthesis and assembly of ribosomal components are fundamental cellular processes and generally well-conserved within the main groups of organisms. Yet, provocative variations to the general schemes exist. We have discovered an unusual processing pathway of pre-rRNA in extreme thermophilic archaea exemplified by Pyrococcus furiosus. The large subunit (LSU) rRNA is produced as a circularly permuted form through circularization followed by excision of Helix 98. As a consequence, the terminal domain VII that comprise the binding site for the signal recognition particle is appended to the 5´ end of the LSU rRNA that instead terminates in Domain VI carrying the Sarcin-Ricin Loop, the primary interaction site with the translational GTPases. To our knowledge, this is the first example of a true post-transcriptional circular permutation of a main functional molecule and the first example of rRNA fragmentation in archaea.