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Transfer-messenger RNA. Macromolecules II May 4, 2009 Jane Yu. Discovery of tmRNA a small, stable RNA. Jain, et al. 1982. Ray and Apirion, 1979. Where is tmRNA found?. All sequenced eubacteria Some rare mitochondrial and plastidial genomes in simple eukaryotes such as diatoms.
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Transfer-messenger RNA Macromolecules IIMay 4, 2009 Jane Yu
Discovery of tmRNAa small, stable RNA Jain, et al. 1982 Ray and Apirion, 1979
Where is tmRNA found? • All sequenced eubacteria • Some rare mitochondrial and plastidial genomes in simple eukaryotes such as diatoms. • Some phage genomes • No nuclear genomes
tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons. A ribosome stuck with nonstop RNA
tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons. A sad ribosome stuck with nonstop RNA
tmRNA also:1) mediates degradation of the aberrant mRNA 2) adds a degradation tag to the aberrant protein for directed proteolysis Functions of tmRNA
Role in human disease Vital for normal growth in: Mycobacterium pneumoniae Neisseria gonorrhaeae Vital for pathogenesis in: Salmonella typhimurium (MP survival) Yersinia pseudotuberculosis (T3SS)