How Your Body Creates Proteins
Protein Synthesis: How Does It Work?
Overview of Protein Synthesis
- Protein synthesis is the biological process through which cells create proteins, which are essential for various functions in the body.
- Proteins are made up of chains of amino acids; the specific amino acids used and their sequence determine the unique structure and function of each protein.
Stages of Protein Synthesis
Transcription
- The first stage, transcription, occurs in the nucleus where DNA instructions for assembling a protein are converted into messenger RNA (mRNA).
- RNA polymerase is the enzyme that initiates transcription by attaching to the DNA template and reading sequences called base triplets, which provide information for assembling amino acids.
- During transcription, uracil replaces thymine in mRNA. Introns (non-coding sections) are removed by enzymes, while exons (coding sections) are spliced together to form functional mRNA.
Translation
- The second stage, translation, takes place in the cytoplasm where ribosomes read mRNA to assemble amino acids into proteins.
- A ribosome attaches to mRNA at a start codon and reads subsequent codons that signal transfer RNA (tRNA), which carries matching anti-codon sequences and specific amino acids.