Nucleasome

Nomenclature Proposal:
Nucleasome is a macromolecular complex that degrades mRNAs into nucleotides. Like Proteasome it exhibits a barrel-like architecture that appears to have evoled to restrict substrate access and prevent indiscriminate degradation.

Formerly this macromolecule is designated as "exosome". Particularly, because exosome is also defined as "a vesicle excreted by mammalian cells" - Exosome (vesicle), and the similar barrel-like structure that degrade peoteins is named proteasome, it is reasonable to name the "nucleotide chain degrading machine" nucleasome.

Discovery

The Nucleasome was discovered in 1997 by Mitchell et al.. ^[1]

Function

In July 2007 S. Vanacova & R. Stefl showed in an article in EMBO reports that the nucleasome acts as quality controller in the nucleus. These machines recognize and degrade not only RNA trimmings, but also incorrectly processed RNAs that contain defects. ^[2]

References

1. ^ L. Mitchell et al. (1997). "The Exosome: A Conserved Eukaryotic RNA Processing Complex Containing Multiple 3′→5′ Exoribonucleases". Cell 91 (4): 457–466. doi:10.1016/S0092-8674(00)80432-8. PMID 9390555. 
2. ^ S. Vanacova and R. Stefl (2007). "The Exosome and RNA quality control in the nucleus". EMBO reports 8 (7): 651–657. doi:10.1038/sj.embor.7401005. PMC 1905902. PMID 17603538. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1905902.