Macromolecules II May 4, 2009 Jane Yu Transfer-messenger RNA.
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Macromolecules II May 4, 2009 Jane Yu Transfer-messenger RNA
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Transcript of Macromolecules II May 4, 2009 Jane Yu Transfer-messenger RNA.
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