Uracil vs Thymine

[aftabac]

Hi

What is the reason that RNA have Uracil instead of Thymine, that is present in DNA??

hope we have nice discussion on this topic

regards
aftab

[admin]

Hello aftab,

that is a very interesting question! Im not sure I see the evolutionary aspect of this as it would be more efficient for DNA and RNA to share the same nucleotides.

Possibly this is a structural/chemical thing is that Uracil in RNA allows more properties consistent to a single stranded molecule (RNA).

Maybe it is used as recognition of RNA vs DNA by the cell machinery somehow?

Not sure, still have to think more about this one.

Any more ideas?

[kmunson779]

Current consensus seems to indicate the liability of cytosine to easily degrade into uracil: with the use of thymine in DNA, any uracil is easily recognized as a damaged cytosine and repaired. See [Only registered users see links. ], [Only registered users see links. ] (scroll to bottom of page), [Only registered users see links. ] (also suggests the extra methyl in thymine plays a role in protein-DNA recognition).

[Priyanka]

I`d like to add one more point to what kmunson has mentioned: Chemically uracil is similar to thymine, although uses less energy to be produced.

[dpriego]

I agree with kmunson779, indeed, the question should be "why DNA has thymine instead of uracil?", and kmunson already answered it.

[telemartnetwork]

This is interesting question. This is chemical bonding or pairing which is only the right one & have no problems in structures.