Make a single base pair substitution mutation in the gene below that results in a protein that is shorter than the protein produce by the original gene. When you are satisfied with your change and its effect, click the "Final Check" button.

Note that a "single base pair substitution mutation" is when a single base is changed to another base. Deletions and insertions are not allowed.

To make a single base pair substitution mutation in a gene, we need to identify the gene sequence and select a specific base to change. In this case, we want to create a mutation that results in a shorter protein than the original gene.

Without knowing the specific gene sequence provided, I cannot give you an exact substitution. However, I can explain the process you should follow to make the mutation:

1. Identify the gene sequence: Obtain the DNA sequence of the gene you are working with. Ideally, this information should be provided or can be obtained from a reliable source.

2. Determine the reading frame: Genes are read in sets of three nucleotides called codons. Identify the reading frame by identifying the start codon (usually ATG) and finding subsequent codons. This will ensure that we are targeting a single amino acid change rather than causing a frameshift mutation.

3. Select a base to substitute: Choose a specific base in the gene sequence for substitution. It should be one that, when changed, results in a codon that codes for a stop codon (e.g., TAA, TAG, or TGA). This will cause the protein to be truncated and shorter in length.

4. Perform the substitution: Change the selected base to the appropriate base so that the new codon codes for a stop codon. For example, if the original base was "C," you could mutate it to "T" to create the stop codon "TAA."

5. Verify the mutation: Check the resulting protein sequence to confirm that it is shorter than the protein produced by the original gene. You may need to translate the gene sequence to its corresponding amino acids using the genetic code.

Once you have followed the steps and made the appropriate base substitution, you can click the "Final Check" button to confirm your alteration and its effect on protein length.