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Old 05-06-2011
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DNA mRNA Splicing of Introns

I read that when intron is spliced from mRNA, it is spliced at the 5' (donor) and 3' (acceptor) ends of the intron.

Can someone explain with a diagram on what the "donor" means and what the "acceptor" means?

Thanks!
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Old 05-07-2011
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I think it may have to do with the formation of the spliceosome during splicing. One snRNP binds to the 5' site, and another binds to the 3' site. These snRNP's, then some together, forming a loop of the intron to be excised. I think the donor/acceptor terms has something to do with that process (honestly I doubt we need to know more than that level of detail).

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Old 05-07-2011
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Thanks, Height. The splicing (donor and receptor) was mentioned in KLN. So why do we not need to know?
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Old 05-07-2011
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Quote:
Originally Posted by usluipek View Post
Thanks, Height. The splicing (donor and receptor) was mentioned in KLN. So why do we not need to know?
I think it's important to understand how splicing, and someone can please correct me if I'm wrong, but I don't think knowing the nitty gritty of donor/acceptor is high yield (especially since the USMLE test more clinical stuff). I think more important would be to understand that mutations can lead to splicing defects for example in the beta globin gene leading to some b-thalassemia.
You may be completely right that since it's in KLN it's important to know, but there's so much to know anyway I try to avoid minutiae
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Old 05-07-2011
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One simple rule of thumb for questions: if the question stem mentions a point mutation near either end on the intron, the answer is "splicing".
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