The tmRNA website
نویسنده
چکیده
tmRNA (also known as 10Sa RNA) is so-named for its dual tRNA-like and mRNA-like nature. It is employed in a remarkable trans -translation process to add a C-terminal peptide tag to the incomplete protein product of a broken mRNA; the tag targets the abnormal protein for proteolysis. tmRNA sequences have been identified in genomes of diverse bacterial phyla, including the most deeply branching. They have also been identified in plastids of the 'red' lineage. The tmRNA Website (http://www.wi.mit. edu/bartel/tmRNA/home ) contains a database currently including sequences from 37 species, with provisional alignments, as well as the tentatively predicted proteolysis tag sequences. A brief review and guide to the literature is also provided.
منابع مشابه
The tmRNA website: reductive evolution of tmRNA in plastids and other endosymbionts
tmRNA combines tRNA- and mRNA-like properties and ameliorates problems arising from stalled ribosomes. Research on the mechanism, structure and biology of tmRNA is served by the tmRNA website (http://www.indiana.edu/~ tmrna), a collection of sequences, alignments, secondary structures and other information. Because many of these sequences are not in GenBank, a BLAST server has been added; anoth...
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tmRNA and SmpB are the main participants of trans-translation, a process which rescues the ribosome blocked during translation of non-stop mRNA. While a one-to-one stoichiometry of tmRNA to the ribosome is generally accepted, the number of SmpB molecules in the complex is still under question. We have isolated tmRNA-ribosome complexes blocked at different steps of the tmRNA path through the rib...
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