Once mRNA has passed out of the nuclear pore, it determines the synthesis of a polypeptide.
- A ribosome attaches to the starting codon, at one end of an RNA molecule.
- The tRNA molecule with a complementary anticodon sequence moves to the ribosome, and pairs up with the sequence on the mRNA.
- A tRNA molecule with a complimentary anticodon pairs up with the next codon on the mRNA.
- The ribosome moves along the mRNA, bringing together two tRNA molecules, each pairing up with the corresponding two codons on the mRNA.
- By means of an enzyme, ATP and and two amino acids on the tRNA are joined by a peptide bond.
- The ribosome moves onto the third codon, on the mRNA linking the amino acids.
- As this happens the first tRNA is released from its amino acid, from the amino acid pool in the cell.
- This process continues until a complete polypeptide chain is created.