If an extra nucleotide is added to an mRNA what will happen?

Question

If an extra nucleotide is added to an mRNA what will happen?
If a nucleotide is taken away from an mRNA what will happen?

Answer 1

the stop codon will change and cause a mutation.

Answer 2

These are mutations in mRNA called FRAMESHIFT MUTATIONS. Adding is called insertion, and taking away is called a deletion. If you add or take away a nucleotide, you move the whole rest of the line down or up and screw up the pattern. Since mRNA codes for proteins, a frameshift mutation can cause all the proteins in a chain to change. And if a STOP codon is shifted, the transcription will not know where to stop and will create an abnormal protein chain. Remember, this is different from a point mutation, which is when one nucleotide is switched for another.

Answer 3

It depends upon where the changes take place. If the insertion or deletion of a single nucleotide takes place in the portion of the mRNA that encodes the information for a protein, then there would be a 'frameshift' mutation, changing the sequence of the protein that is being synthesized. Interestingly however, mRNA molecules have sequences beyond those that 'code' for the protein. These 'untranslated' sequences can influence the stability of the mRNA, how quickly it gets translated, and a number of other things. Changes in these regions of the mRNA will not change the synthesis of the protein at all.

Answer 4

This depends on where the nucleotide is added. Both might change the function of the protein that the mRNA translates into. This depends on whether the new nucleotide sequence leads to different amino acid sequence. If it does, the new protein will either have a new amino acid that shouldn't be there or it will lose an amino acid that it should have. As the overall protein structure is affected due to losing or gaining of the amino acid, both adding a nucleotide or losing a nucleotide from an mRNA might lead to a gain of a new function or losing of a function of the protein translated.

Answer 5

If a extra nucleotide is added the codons will shift.

If a nucleotide is taken away the codons will still shift

Answer 6

Addition or deletion of one nucleotide in a mRNA would result in a framshift mutation, since tRNA reads 3 nucleotides at a time to determine which nucleic acid to add to the protein.



For example, if the mRNA reads:

UUU-GCU-CAU-CGC

--it translates to:

Phe-Ala-His-Arg



But if you added an A somewhere:

UUA-UGC-UCA-UCG-C

--then it translates to:

Leu-Cys-Ser-Ser



The same thing would happen if you deleted one nucleotide.

Answer 7

Wherever the nucleotide is added, it shifts all the codons from that point on. Codons are sets of three base pairs.



If a sentence said

our car got old



and you add a letter in car, it changes all the groupings from there on



our caa rgo tol d



Not the same at all.

Answer 8

It shifts all the codons after it and could have several effects. Some of which are that the gene isn't expressed, or part of it are expressed, or it is expressed but incorectly. Sorry I can't give you a more in depth explanation.