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How is tRNA Synthesised?

  1. Aug 17, 2011 #1
    mRNA is synthesized during transcription,but where and how are the tRNA's synthesized?
  2. jcsd
  3. Aug 17, 2011 #2


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    tRNAs are also made by transcription, by a different RNA polymerase (RNA polymerase III) than is used for mRNA synthesis (RNA polymerase II). Because the factors involved in mRNA capping and polyadenylation are physically associated with RNA polymerase II and not RNA polymerase III, tRNAs do not undergo capping and polyadenylation like mRNAs. tRNAs, however do undergo extensive post-transcriptional processing to get them into their final form.
  4. Aug 19, 2011 #3
    So you need tRNA molecules to create more tRNA molecules? Because I would think initial tRNA is necessary to create RNA polymerase, Thats interesting, wonder how the first tRNA evolved. And you would need a DNA sequence that aligned with the produced type of tRNA in order to create proteins, maybe DNA evolved around tRNA... Hmmmm Hahah, Off topic, I know.
  5. Aug 19, 2011 #4


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    What's fascinating about RNA is that it can act both as genetic material (like DNA) and as enzymatic molecules (like proteins) e.g http://en.wikipedia.org/wiki/Ribozyme" [Broken] posits that early life used RNA in both capacities until the evolution of proteins took over most of the jobs.
    Last edited by a moderator: May 5, 2017
  6. Aug 23, 2011 #5
    Ahh yeah I've head of Ribozymes before, I'll have to look more into that. http://www.newscientist.com/article/dn18623-did-midwife-molecule-assemble-first-life-on-earth.html might find this interesting aswell
    Last edited by a moderator: May 5, 2017
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