3. Translation process

Figure 19a Figure 19b Figure 19c

Figures 19a-c

3.1 Elongation of translation

Step 3: Translocation

The ribosome moves one codon (= 3 nucleotides) forward on mRNA towards the 3’ end in two steps: first, along the large subunit, and then along the small subunit.

tRNAs do not move along the mRNA , but transfer to another site on the ribosome:

  • tRNA devoid of an amino acid moves from the P-site to the E-site and then exits

  • Peptidyl tRNA moves from the A-site to the P-site

  • The A-site becomes free

The cycle can begin a new step.