Bitter Taste (Activity)

Exercise: Coding Bitterness

Prior to this exercise, review the Central Dogma.
The full coding sequence of TAS2R38 is 1,002 bases (334 amino acids) long. A segment of the gene is shown below where the SNP (in red) occurs. Variant 1 is the version of the gene that encodes for the ability to taste PTC. Variant 2 is the version of the gene that is unable to bind to PTC. This SNP mutation is called a missense mutation because it changes the amino acid. Some mutations cause the insertion of a premature stop codon. This nonsense mutation results in a truncated protein and can be disastrous to the function. We already know that the simple substitution of one nucleotide translates to a change in one amino acid and determines the ability to taste PTC. Imagine if a large group of amino acids from the protein was missing.
With template strand (“Complement”) information:

  1. Write the sequence of the coding strand.
  2. Write the sequence of the mRNA
  3. Use the Genetic Code Chart to translate the amino acid sequence

Variant 1
Coding Strand : 5′-
Complement :    3′-TTC TCC GTC CGT GAC TCG-5′
mRNA : 5′-
Amino Acid :
Variant 2
Coding Strand : 5′-
Complement :    3′-TTC TCC GTC GGT GAC TCG-5′
mRNA : 5′-
Amino Acid :

 

 

Aminoacids table

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