how could one change in a dna molecule nucleotide alter the formation of the translated protein?

Answer 1

As explained in many other answers each nucleotide is part of a triplet codon that specifies an amino acid making up the translated protein. A change in one nucleotide may or may not alter the formation of the translated protein due to the degeneracy of the codons.

1) STRUCTURE of translated protein: Changing one nucleotide could mean that a different amino acid becomes incorporated into the protein forming a protein that may not produce the same tertiary structure or may not bind the same proteins it needs to efficiently, depending on what the protein's normal function is. Thus, function is decreased or lost due to a change in structure. Also, changes in structure can cause a dominant negative effect by binding and/or altering other processes or proteins the normal protein doesnt interact with.

2) LENGTH of translated protein: the formation of the translated protein could be altered in length meaning a start (methionine) AUG or stop , UAA, UAG, or UGA codon has been changed so that the protein is either longer or shorter in length. Again, its function is compromised or deleted.

3) NO FORMATION of translated protein OCCURS: It is possible that no protein will be made if the start codon is changed by one nucleotide.

Answer 2

This is because the information for synthesizing a protein is contained within the sequence of the DNA in a three "letter" code, the triplet code. Most of the amino acids can be specified in the triplet code by more than one specific triplet of nucleotides in the DNA. For example, while the amino acid methionine is specified by the triplet "codon" 'ATG', the amino acid proline can be specified by any of the following four triplet codons, CCA, CCG, CCT, or CCC. The changes that occur in the formation of proteins based on single nucleotide changes in DNA occur when they change the triplet codon to one that encodes a different amino acid. For instance a mutation that changes GGA (which codes for glycine) to GCA (which codes for alanine) leads to an alteration in the intended structure of the encoded protein.

Answer 3

DNA is composed of nucleotides. Three nucleotides in a row is called a Codon. Codons coorespond to a specific amino acid in a protein (proteins are composed of chains of amino acids). If one nucleotide is changed the codon sequence is changed and a different amino acid is produced. This different amino acid is then incorporated into the protein causing a difference in the translated protein.

Answer 4

Since each trinucleotide codes for an amino acid, a change in one of the triplet codons could alter the amino acid which is put into the growing protein. For example, substitution can lead to the mRNA codon going from AUG (methionine) to CUG (leucine). On the other hand, the code is somewhat degenerate (meaning that some triplets code for the same amino acid), so that a change from CCC to CCA would still code for proline and not be noticed.

Answer 5

It relies upon on the style of replace it particularly is. If it particularly is a element mutation, the replace could desire to be significant, or it may desire to have not have been given any result. the main straightforward style of genetic sickle cellular anemia is brought about by potential of a element mutation (substitution) that alters the amino acid in the 6th place of the beta hemoglobin chain. This makes the full hemoglobin molecule behave in a distinctive way. physique shift mutations could have a large result on the polypeptide, finding on the place the mutation happens. If the mutation is close to the front of the polypeptide, the full protein could desire to be inactive.

Answer 6

In sickle cell anaemia, GAA coding for glutamic acid is replaced by GUA coding for valine. That is, a single base difference. The valine has different properties to glutamine, and the haemoglobin molecule does not fold properly, so functions differently to normal haemoglobin.
This is one example of how a single change can influence the entire protein molecule. Folding in proteins affects such things as overall charge, and binding to other proteins and receptor sites.

Answer 7

The sequence of nucleiotides codes for the sequence of aminoacids in the protein. Three nucleotides stand for one aminoacid. If you change the sequence(say, TGC to GGC) the tRNA molecule will not recognize the code as the appropriate, and a different tRNA molecule (one which recognizes the GCG sequence) will attach to the site, introducing a different aminoacid into the nascent protein