To determine the DNA sequence that encodes for the protein sequence consisting of Serine (Ser), Histidine (His), Threonine (Thr), and a Stop codon, we first need to know the corresponding codons for these amino acids.
The codons for the amino acids are as follows:
- Serine (Ser): UCU, UCC, UCA, UCG, AGU, AGC (we can use UCU for this example)
- Histidine (His): CAC, CAU (we can use CAU for this example)
- Threonine (Thr): ACU, ACC, ACA, ACG (we can use ACU for this example)
- Stop codon: UAA, UAG, UGA (we can use UAA for this example)
Now, putting this together, the mRNA sequence corresponding to the amino acid sequence would be:
- UCU (Ser) - CAU (His) - ACU (Thr) - UAA (Stop)
Next, we need to convert this mRNA sequence to the corresponding DNA sequence. To do this, we will replace uracil (U) in the RNA with thymine (T) in the DNA:
- DNA sequence: ACT - GTA - TGA - ATT
So, the DNA sequence that encodes the amino acids Serine, Histidine, Threonine, and a Stop codon can be represented as: AGT CAT ACA TAA
Remember that DNA is double-stranded, so this would actually represent one strand, and the complementary strand would have the opposite bases. But the above sequence reflects one of the strands that encodes the desired protein sequence.