Abstract : tmRNA acts to rescue stalled bacterial ribosomes while encoding a peptide tag added trans-translationally to the nascent peptide, targeting it for proteolysis. The permuted gene structure found in a group of cyanobacteria is shown to produce a two-piece mature tmRNA, as had been observed previously for the independently permuted gene of alpha-proteobacteria. The pieces have been mapped onto the gene sequence and aligned for the permuted cyanobacterial tmRNA sequences, including four novel sequences. Structural probing and base pair co-variations support a secondary structure model in which two pairings in the tRNA-like domain hold the two pieces together, and the coding piece bearing the tag reading frame additionally contains a single transient pseudoknot and three other stem-loops. This represents a dramatic reduction in pseudoknot number from the five present in one-piece cyanobacterial tmRNA.
https://www.hal.inserm.fr/inserm-00718155 Contributor : Annick LefevreConnect in order to contact the contributor Submitted on : Monday, July 16, 2012 - 1:32:05 PM Last modification on : Wednesday, March 30, 2022 - 2:34:47 PM Long-term archiving on: : Wednesday, October 17, 2012 - 2:36:05 AM
Cyril Gaudin, Xiong Zhou, Kelly P. Williams, Brice Felden. Two-piece tmRNA in cyanobacteria and its structural analysis.. Nucleic Acids Research, Oxford University Press, 2002, 30 (9), pp.2018-24. ⟨10.1093/nar/30.9.2018⟩. ⟨inserm-00718155⟩