The following DNA nucleotides are found near the end of a pr

The following DNA nucleotides are found near the end of a prokaryotic transcription unit. Find the intrinsic terminator in this sequence. 3\'AGCATACAGCAGACCGTTGGTCTGAAAAAAGCATACA-5\' Mark the point at which termination will occur. Draw a picture of the RNA that will be transcribed from this DNA which includes the nucleotide sequence and any secondary structure form.

Solution

Please find the answers below:

Part 1: The parent sequence is:

3\'-AGCATACAGCAGACCGTTGGTCTGAAAAAAAGCATACA-5\'

Thus, the triplet codon sequence would be :

3\'-AGCATACAGCAGACCGTTGGTCTGAAAAAAAGCATACA-5\'

It can be seen that the stop codon TGA arrives at near middle of the whole sequence and thus, the chain will terminate at this position (bold and underlined)

Part 2: The RNA that will be transcribed from this DNA will be given by:

5\'- UCG-UAU-GUC-GUC-UGG-CAA-CCA-3\'

The secondary structure of this RNA will be dependent upon the nature of nucleotides it contains. Some mRNA structures containing self-complementary seqeunces or palndrome seqeunces make complex secondary setructures such as hairpin loops etc. However, since this mRNA does not contain any palindrome or self-complimentary seqeuences, its secondary structure will be linear only.