If the sequence of the coding strand in a transcription unit is written as follows:
5-ATGCATGCATGCATGCATGCATGCATGC-3
Write down the sequence of mRNA.
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 and Explanation
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
Top Questions on Molecular Basis of Inheritance
- The RNA triplet UAG acts as a stop codon which terminates the synthesis of a polypeptide. Below is given a strand of DNA which codes for four amino acids.
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DNA strand:
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Concepts Used:
Transcription
The very first stage of gene expression is the procedure of transcription. In this procedure, mRNA is the place where the genetic information is stored which later aids in encoding a protein. In this process, the DNA strand acts as a guide in the making of mRNA. Despite the fact that there is one exception which is adenine base pairs with uracil instead of thymine.
Transcription Unit:
The transcription unit is a set of freshly combined RNA molecules that have been transcribed from DNA. The cause is to encode at least one gene. A protein that has been encoded or encrypted with a DNA transcription unit may have a coding sequence. Transcription has a lower copying fidelity rate when differentiated from DNA replication.
The Stages of Transcription:
The procedure of transcription is enzymatically catalyzed into three steps:
- Initiation
- Elongation
- Termination