Which of the Following Genetic Elements Is Transcribed Into A Single mRNA?
Gene expression is an essential process in the body, wherein the genetic code stored in DNA is converted into a functional protein. Transcripts, or mRNA molecules, are formed when a gene is transcribed from DNA. In the context of genetic elements, mRNA molecules may be formed from a single gene or several genes at once. In this article, we will discuss which of the following genetic elements is transcribed into a single mRNA.
The first genetic element we will discuss is the trp operon. This is a set of five genes found in bacteria, which are transcribed into a single mRNA molecule. The genes contained in the trp operon are responsible for the biosynthesis of the amino acid tryptophan. As this molecule is used for various biological purposes, the trp operon is kept under tight regulation.
The second genetic element is the tRNA gene. This is a single gene which codes for a transfer RNA molecule. This enzyme is responsible for the transfer of amino acids to the ribosome during protein synthesis. This ensures that the correct amino acids are incorporated in the correct order, so that a functional protein can be formed.
The third genetic element is the 5′ untranslated region (UTR) of a gene. This region is located upstream of the start codon of a gene and contains multiple sequences that regulate the behavior of the transcript. Unlike a single gene or tRNA gene, the 5′ UTR is not transcribed into a single mRNA molecule.
Finally, the fourth genetic element is an intron. Introns are sections of DNA that do not contain coding information. When a gene is transcribed, the introns are transcribed along with the exons into a single mRNA molecule. Introns are then removed from the mRNA molecule through a process called splicing, which allows the mRNA molecule to be translated into a functional protein.
In conclusion, three of the four genetic elements we discussed in this article can be transcribed into a single mRNA molecule. These are the trp operon, the tRNA gene, and the intron. The 5′ UTR, however, is not transcribed into a single mRNA molecule.