Alternate conformational trajectories in ribosome translocation

Area of Science:

• Molecular Biology
• Biochemistry
• Structural Biology

Background:

• Protein synthesis relies on accurate mRNA-tRNA movement through the ribosome (translocation).
• A key step involves the small subunit head domain swiveling around rRNA hinge elements.

Purpose of the Study:

• To investigate alternative hinge elements that can facilitate ribosome translocation.
• To understand how modifications to hinge elements affect the dynamics of translocation.

Main Methods:

• Iterative selection techniques were used to identify novel hinge elements.
• Molecular dynamics simulations were employed to analyze ribosome conformational changes.
• Experiments were conducted both in vitro and in vivo.

Main Results:

• Successfully derived alternate hinge elements that support translocation.
• Observed diverse swivel kinetics, hinge motions, and head domain trajectories in altered pathways.
• Identified essential and malleable motions and intermediates during translocation.

Conclusions:

• Protein synthesis translocation exhibits significant plasticity.
• Understanding these alternate pathways deepens our knowledge of the conformational landscape of protein synthesis.