The key difference between transcription and translation is that transcription refers to the process of producing a mRNA molecule for the DNA of a gene while translation refers to the process of synthesizing an amino acid sequence from the transcribed mRNA molecule.
Genes are the units of heredity. Simply they are fragments of DNA. They contain the genetic information (genetic code) to make proteins. In order to produce proteins, they undergo gene expression. Hence, gene expression is the process of synthesizing a protein molecule (gene product) from the genetic information hidden in the gene. Gene expression occurs via two major steps such as transcription and translation. Transcription is the first step, and it is followed by the translation, which is the second major step of gene expression.
1. Overview and Key Difference
2. What is Transcription
3. What is Translation
4. Similarities Between Transcription and Translation
5. Side by Side Comparison – Transcription vs Translation in Tabular Form
What is Transcription?
Transcription is the first step of the gene expression. It is the process of producing a mRNA molecule from a DNA template. Transcription occurs inside the nucleus of eukaryotes. It is an enzyme-catalyzed reaction. RNA polymerase is the enzyme which catalyzes this process. Among the two strands of DNA in a gene, one serves as the coding sequence while the other is the non-coding sequence.
Non-coding sequence serves as the template in transcription since it is complementary to the coding sequence. RNA polymerase enzyme reads the nucleotides of the coding sequence and adds correct complementary ribonucleotides and constructs the mRNA molecule, which contains the genetic code of the coding sequence. Hence, the resulting mRNA sequence becomes identical to the coding sequence. However, since it is an RNA sequence, RNA polymerase adds uracil instead of thymine during the transcription.