Question

If there was an error during transcription and the mRNA strand started with UCC, would this change the final

insulin protein? Explain why or why not.

Answer 1

A transcription error such as starting with UCC instead of the correct mRNA sequence could change the final insulin protein by altering the structure and function of the resultant protein due to the incorporation of different amino acids. This can have impacts on critical processes like blood glucose regulation.

Step-by-step explanation:

If there was an error during transcription and the mRNA strand started with UCC instead of the correct sequence, this could indeed alter the final insulin protein. During the translation process, mRNA codons are read in sets of three nucleotides to assemble the corresponding amino acids into a polypeptide chain. Each set of three nucleotides, or codon, corresponds to a specific amino acid or a stop signal during protein synthesis. If the mRNA strand starts with the wrong codon, this can lead to a different set of amino acids being incorporated into the protein, potentially changing its structure and function. This is known as a point mutation, and depending on where it occurs and whether it is a silent, missense, or nonsense mutation, it could have minor or severe effects on the protein's function.

Using a codon chart, we can identify the amino acid sequence produced by this DNA template. However, in the case of a mutation in the insulin gene, such as starting with UCC, the mRNA may encode for serine instead of the original amino acid. This could lead to changes in the protein's folding, stability, and function.

Mutations like this are significant because insulin is a critical hormone in the regulation of blood glucose levels. Any change in the structure of insulin can impair its ability to bind to its receptor, which in turn can disrupt glucose homeostasis in the body and potentially lead to conditions like diabetes.

Answer 2

If there was an error during transcription and the mRNA strand started with UCC instead of the correct start codon AUG, it would likely result in a change in the final insulin protein. This is because the start codon AUG serves as the initiation signal for protein synthesis, and it codes for the amino acid methionine, which is typically the first amino acid incorporated into a protein during translation.

Insulin is a hormone that is composed of two peptide chains, referred to as the A-chain and B-chain, which are connected by disulfide bonds. The synthesis of insulin involves the transcription of the insulin gene into mRNA and the subsequent translation of mRNA into a protein.

During translation, the mRNA is read in sets of three nucleotides called codons. Each codon corresponds to a specific amino acid, which is added to the growing protein chain. The start codon AUG initiates the process and signals the addition of methionine as the first amino acid.

If the mRNA strand starts with UCC instead of AUG, the translation process would likely result in the addition of a different amino acid instead of methionine at the beginning of the insulin protein. This alteration in the protein's primary structure can have significant effects on its folding, stability, and ultimately its function.

Therefore, the error during transcription, specifically in the start codon, could lead to an incorrect amino acid sequence at the beginning of the insulin protein, potentially impacting its structure and function.