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Nucleotides in the coding region of DNA are transcribed into mRNA.
mRNA, in turn, is translated into a polypeptide via the ribosome.
Three (3) nucleotides correspond to one amino acid. In other words, if the nucleotides in question are AAA, those nucleotides will be transcribed into their mRNA complement, UUU, which in turn will be translated into the amino acid phenylalanine via the ribosome.
Now, if you remove one of those nucleotides, say the first A of the AAA, everything gets screwed up. You get what is caused a frameshift. Say originally you had AAAUAG. As I mentioned, AAA would eventually become phenylalanine, and UAG is a stop codon, which would tell the ribosome to stop translating: the polypeptide is complete. But if the first A of the AAA is removed -- the ribosome still wants to read in threes! So it will read AAU, and code asparagine instead of phenylalanine, and moreover . .. it will keep translating making a polypeptide much longer than evolution intended!
Wiki User
∙ 13y ago
Wiki User
∙ 12y agoPolypeptide chains are formed by reading DNA base sequences in groups of three.
If one of the bases of DNA is deleted than all of the bases are shifted down one and the polypeptide chain is radically different because every group after the deletion is now different.
If an entire group is deleted it has less of an effect and sometimes no effect at all depending on how important the group was.
For insertion it is very similar. If one base is added then all the bases after it are shifted up on and all the groups after the insertion are different.
If a whole group is added (very unlikely in the natural world, only really happens in a lab) then the effect can be small or none at all.
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What mutations would be considered frameshift mutations?
In mature mRNA, there is a start codon (AUG) that instructs ribosome to begin translation. Thereafter, every 3 bases are read as a "code word" calling for a particular amino acid to enlogate the polypeptide chain or to STOP and release the polypeptide. If 1 or 2 nucleotides are deleted or inserted into this sequence, it causes the reading frame to shift. This usually results in misreading of the sequence here is an example: AUG - AGC - ACC - TAA - GGG - etc. (if we delete the first C we get....) AUG - AGA - CCT - AAG - GG ( this is obviously not going to code for the same amino acid sequence)
How could a change in a polypeptide affect cell activity?
Enzymes are derived from polypeptide chains, enzymes are responsible for adequate cell activity. Therefore, if a polypeptide chain is not properly composed, the enzyme will be dysfunctional, hence leading to a depletion in cell activity.
What do you call a chain of 25 amino acids?
a chain of 25 amino acids can be called a peptide chain ---------------------------------------------------------------------------------- Two or united amino acids form a *dipeptide* Three a *tripeptide* Ten or more a *polypeptide* More than 50 *protine* Therefore a chain of 25 amino acids is a polypeptide :D
Polypeptide chain looks like what?
A necklace with beads
Where is blueprint for the polypeptide chain that is insulin found?
DNA
What mutations would be considered frameshift mutations?
In mature mRNA, there is a start codon (AUG) that instructs ribosome to begin translation. Thereafter, every 3 bases are read as a "code word" calling for a particular amino acid to enlogate the polypeptide chain or to STOP and release the polypeptide. If 1 or 2 nucleotides are deleted or inserted into this sequence, it causes the reading frame to shift. This usually results in misreading of the sequence here is an example: AUG - AGC - ACC - TAA - GGG - etc. (if we delete the first C we get....) AUG - AGA - CCT - AAG - GG ( this is obviously not going to code for the same amino acid sequence)
What chain is sequences of amino acids that is the foundation for the basic structure of a protein?
polypeptide chain
Caused by the insertion or deletion of nucleotides in DNA?
The deletion or insertion of one nucleotide into the DNA sequence will result in a frameshift mutation which changes the reading frame that the tRNA follows when assembling amino acids from the DNA sequence. Each amino acid is coded for by a codon of three specific nucleotides. Shifting this frame can result in a different amino acid being added to the growing polypeptide chain. Also, a stop codon can be read and thus prematurely end the polypeptide chain. This creates incorrect and/or incomplete proteins. This could lead to serious problems if essential proteins are being saccrificed due to the mutation.
Is polypeptide chain a carbohydrate protein or lipid?
A polypeptide chain is a chain of amino acids, which make up proteins
A chain of 67amino acids would be called?
A polypeptide.
What chain is a sequence of amino acids that is the foundation for the basic structure of a protein?
polypeptide chain
A chain of amino acids forms what?
A chain of amino acids form a polypeptide chain. Once the polypeptide chain goes under a seris of folds, due to side chain reactions it becomes a functional protien.
How could a change in a polypeptide affect cell activity?
Enzymes are derived from polypeptide chains, enzymes are responsible for adequate cell activity. Therefore, if a polypeptide chain is not properly composed, the enzyme will be dysfunctional, hence leading to a depletion in cell activity.
What effect does deletion mutation have on the chain?
It will shorten the chain.
Is polypeptide chain a protein?
A polypeptide chain is made up amino acids that form from a peptide bond. The polypeptide chain makes up a protein; therefore, the type of protein is contingent on the number of chains present.
What do you call a chain of 25 amino acids?
a chain of 25 amino acids can be called a peptide chain ---------------------------------------------------------------------------------- Two or united amino acids form a *dipeptide* Three a *tripeptide* Ten or more a *polypeptide* More than 50 *protine* Therefore a chain of 25 amino acids is a polypeptide :D
A long chain of amino acids?
polypeptides - The Dude That is Friends with THE DUDE
