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Protein synthesis is the creation of proteins using DNA and RNA. Protein Synthesis is a two step process. Transcription - Protein synthesis starts in the nucleus, where the DNA is held. DNA structure is two chains of sugars and phosphates joined by pairs of nucleic acids; Adenine, Guanine, Cytosine, and Thymine. Similar to DNA replication, the DNA is "unzipped" by the enzyme helicase, leaving the single nucleotide chain open to be copied. RNA polymerase reads the DNA strand, and synthesizes a single strand of messenger RNA (mRNA). This single strand of mRNA leaves the nucleus through nuclear pores, and migrates into the cytoplasm where it joins with ribosomes.Where protein synthesis occurs by the formation of amino acids. Note: in the new RNA strand, the nucleotide Uracil takes the place of Thymine.
Translation - the process of converting the mRNA codon sequences into an amino acid polypeptide chain.
1. Initiation - A ribosome attaches to the mRNA and starts to code at the FMet codon (usually AUG, sometimes GUG or UUG).
2. Elongation - tRNA brings the corresponding amino acid to each codon as the ribosome moves down the mRNA strand.
3. Termination - Reading of the final mRNA codon (aka the STOP codon), which ends the synthesis of the peptide chain and releases it.