Eukaryotic translation

Eukaryotic translation is the biological process by which messenger RNA (mRNA) is translated into proteins in eukaryotes. It is part of the larger process of protein biosynthesis. The process is complex and involves numerous components and steps.

Overview

In eukaryotes, translation occurs in the cytoplasm, where the ribosomes are located. Ribosomes are made of a small and large subunit that surround the mRNA. In translation, messenger RNA (mRNA) is decoded to produce a specific polypeptide according to the rules specified by the trinucleotide genetic code.

Initiation

The initiation of eukaryotic translation involves the assembly of the components of the translation system, which are: the mRNA to be translated, the tRNA that carries the starting amino acid, the two subunits of the ribosome, and the various initiation factors.

The initiation phase begins with the binding of several initiation factors and a special initiator tRNA to the small ribosomal subunit. The mRNA then binds to this complex, followed by the large ribosomal subunit. The assembled initiation complex then begins to scan the mRNA for the start codon.

Elongation

Elongation is the stage where the amino acid chain gets longer. This stage involves the recognition of the tRNA anticodon, peptide bond formation, translocation, and the repeating of the process until a stop codon is reached.

Termination

Termination of the eukaryotic translation process occurs when a stop codon (UAA, UAG, or UGA) is encountered. When the ribosome encounters the stop codon, the growing polypeptide is released and the ribosome is disassembled.

Regulation

The regulation of eukaryotic translation can occur at the initiation phase. The rate of initiation is a major determinant of the rate of protein synthesis. Regulation of translation can impact the global rate of protein synthesis which is closely coupled to the metabolic and proliferative state of a cell.

See also

• Protein biosynthesis
• Translation (biology)
• Ribosome
• Messenger RNA
• Transfer RNA