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You are correct in saying that Crick, in his Wobble Hypothesis, proposed that “the base on the third position of the codon and that on the anticodon need not be complementary”, but the “need not be” in your statement is a paraphrase of the “some” in Crick’s original statement: “It is suggested that while the standard base pairs may be used rather ...


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Apart from the polycistronic case there is another possibility of one mRNA yielding multiple proteins. By one mRNA, I mean that the RNA is not in any way altered because of RNA editing or other mechanisms. Translation can be initiated at alternative sites leading to production of different protein products (Touriol et al., 2003). VEGF is one of the genes ...


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I believe, your book refers to polycistronic mRNA. This is mRNA where multiple genes are encoded together in one mRNA and are often (but not necessarily) translated one after another. This is mainly found in prokaryotes where the proteins encoded on the same mRNA often form a metabolic pathway together.


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You can come at mRNA from two directions. Remember that human genes are largely monocistronic, in other words they often code for a single protein. If we look at prokaryotes, however, polycistronic genes such as those in operons are very much possible. From a single lac mRNA you can get multiple proteins. For humans with monocistronic genes, you can code ...


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As this question is a first post it is probably just a basic question about protein synthesis, which @Sean Johnson has answered adequately. However I’m not quite sure. And as I used to work in protein synthesis (but am a rather out of touch now) I decided to look at the recent literature a little to address some more esoteric or obscure questions it raised ...


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Whether or not there are multiple start and stop codons depends on what you mean by "start codon" and "stop codon". The start codon has the sequence "AUG", and the stop codon has the sequence "UAG", "UAA", or "UGA". Both the pre-mRNA and the mature-mRNA can, and usually do, contain multiple instances of all of these sequences. However, only one "AUG" ...


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Yes, tRNA can form dimers. For example it was shown that E. Coli tRNA GCC forms homodimers, i.e. two identical molecules interact with each other. In this case the dimerization occurs between the anti-codon loops (what was probably meant with UUU and AAA). References: Sequence and structure of naturally-occurring tRNA transcripts and site-directed ...



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