Skip to main content
Article thumbnail
Location of Repository

The rnb Gene of Synechocystis PCC6803 Encodes a RNA Hydrolase Displaying RNase II and Not RNase R Enzymatic Properties

By Rute G. Matos, Arsénio M. Fialho, Mordechai Giloh, Gadi Schuster and Cecília M. Arraiano


Cyanobacteria are photosynthetic prokaryotic organisms that share characteristics with bacteria and chloroplasts regarding mRNA degradation. Synechocystis sp. PCC6803 is a model organism for cyanobacteria, but not much is known about the mechanism of RNA degradation. Only one member of the RNase II-family is present in the genome of Synechocystis sp PCC6803. This protein was shown to be essential for its viability, which indicates that it may have a crucial role in the metabolism of Synechocystis RNA. The aim of this work was to characterize the activity of the RNase II/R homologue present in Synechocystis sp. PCC6803. The results showed that as expected, it displayed hydrolytic activity and released nucleoside monophosphates. When compared to two E. coli counterparts, the activity assays showed that the Synechocystis protein displays RNase II, and not RNase R characteristics. This is the first reported case where when only one member of the RNase II/R family exists it displays RNase II and not RNase R characteristics

Topics: Research Article
Publisher: Public Library of Science
OAI identifier:
Provided by: PubMed Central
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://www.pubmedcentral.nih.g... (external link)
  • Suggested articles


    1. (2007). 59-to-39 exoribonuclease activity in bacteria: role of RNase J1 in rRNA maturation and 59 stability of mRNA.
    2. (2005). A single mutation in Escherichia coli ribonuclease II inactivates the enzyme without affecting RNA binding.
    3. (2007). A single subunit, Dis3, is essentially responsible for yeast exosome core activity.
    4. (2000). Action of RNase II and polynucleotide phosphorylase against RNAs containing stem-loops of defined structure.
    5. (1996). Addition of destabilizing poly (A)-rich sequences to endonuclease cleavage sites during the degradation of chloroplast mRNA.
    6. (2010). Barbas A
    7. (2009). Biochemical characterization of the RNase II family of exoribonucleases from the human pathogens Salmonella typhimurium and Streptococcus pneumoniae.
    8. (2006). Characterization of the functional domains of Escherichia coli RNase II.
    9. (2008). Characterizing ribonucleases in vitro examples of synergies between biochemical and structural analysis.
    10. (2003). Cold shock induction of RNase R and its role in the maturation of the quality control mediator SsrA/ tmRNA.
    11. (2001). Cold-regulated genes under control of the cold sensor Hik33 in Synechocystis.
    12. (1997). Comparative sequence analysis of ribonucleases HII, III,
    13. (2007). Dark-induced mRNA instability involves RNase E/G-type endoribonuclease cleavage at the AU-box and SD sequences in cyanobacteria. Mol Genet Genomics 278: 331–346. The Synechocystis Hydrolase Acts as a RNase II PLoS
    14. (2009). Determination of Key Residues for Catalysis and RNA Cleavage Specificity: one mutation turns RNase II into a ‘‘super-enzyme’’.
    15. (1998). Different cleavage specificities of RNases III from Rhodobacter capsulatus and Escherichia coli.
    16. (1991). Enzymatic basis for hydrolytic versus phosphorolytic mRNA degradation in Escherichia coli and Bacillus subtilis.
    17. (2001). Escherichia coli ribonuclease II.
    18. (2010). Escherichia coli RNase R has dual activities, helicase and RNase.
    19. (2007). Exoribonuclease R in Mycoplasma genitalium can carry out both RNA processing and degradative functions and is sensitive to RNA ribose methylation.
    20. (2003). Genomic analysis in Escherichia coli demonstrates differential roles for polynucleotide phosphorylase and RNase II in mRNA abundance and decay.
    21. (2008). Loss of RNase R induces competence development in Legionella pneumophila.
    22. (2004). MUSCLE: multiple sequence alignment with high accuracy and high throughput.
    23. (2008). New insights into the mechanism of RNA degradation by ribonuclease II: identification of the residue responsible for setting the RNase II end product.
    24. (2008). robust phylogenetic analysis for the non-specialist.
    25. (2001). Polynucleotide phosphorylase functions as both an exonuclease and a poly(A) polymerase in spinach chloroplasts.
    26. (2011). Proteomics Reveals a Role for the RNA Helicase crhR in the Modulation of Multiple Metabolic Pathways during Cold Acclimation of Synechocystis sp.
    27. (2002). Purification and characterization of the Escherichia coli exoribonuclease RNase R. Comparison with RNase II.
    28. (2003). Quality control of ribosomal RNA mediated by polynucleotide phosphorylase and RNase R.
    29. (2003). RNA polyadenylation and degradation in Cyanobacteria are similar to the chloroplast but different from Escherichia coli.
    30. (2006). RNA polyadenylation and degradation in different Archaea; roles of the exosome and RNase R.
    31. (2009). RNase R mutants elucidate the catalysis of structured RNA: RNA-binding domains select the RNAs targeted for degradation.
    32. (2000). Selection of conserved blocks from multiple alignments for their use in phylogenetic analysis.
    33. (2011). Swapping the domains of exoribonucleases RNase II and RNase R: conferring upon RNase II the ability to degrade dsRNA.
    34. (2003). SWISS-MODEL: An automated protein homology-modeling server.
    35. (2010). The critical role of RNA processing and degradation in the control of gene expression.
    36. (1997). The mechanism of preferential degradation of polyadenylated RNA in the chloroplast. The exoribonuclease 100RNP/polynucleotide phosphorylase displays high binding affinity for poly(A) sequence.
    37. (1994). The processive reaction mechanism of ribonuclease II.
    38. (2002). The PyMOL Molecular Graphics System, 0.83 ed. DeLano Scientific,
    39. (1999). The reaction mechanism of ribonuclease II and its interaction with nucleic acid secondary structures.
    40. (2007). The role of the S1 domain in exoribonucleolytic activity: substrate specificity and multimerization.
    41. (2006). The SWISS-MODEL workspace: a web-based environment for protein structure homology modelling.
    42. (2009). The SWISSMODEL Repository and associated resources.
    43. (2006). Unravelling the dynamics of RNA degradation by ribonuclease II and its RNAbound complex.

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.