Question:
If the sequence of the coding strand in a transcription unit is written as follows:
5'-ATGCATGCATGCATGCATGCATGCATGC-3'
Write down the sequence of mRNA.
Solution:
If the coding strand in a transcription unit is
5’− ATGCATGCATGCATGCATGCATGCATGC-3’
Then, the template strand in 3’ to 5’ direction would be
3’ − TACGTACGTACGTACGTACGTACGTACG-5’
It is known that the sequence of mRNA is same as the coding strand of DNA.
However, in RNA, thymine is replaced by uracil.
Hence, the sequence of mRNA will be
5’ − AUGCAUGCAUGCAUGCAUGCAUGCAUGC-3’