Measurement of internal movements within the 30 S ribosomal subunit using Forster resonance energy transfer

作者：Hickerson R; Majumdar ZK; Baucom A; Clegg RM; Noller HF^*

来源：Journal of Molecular Biology, 2005, 354(2): 459-472.

DOI：10.1016/j.jmb.2005.09.010

• FRET
• subunit association
• rRNA
• ribosomal proteins

We have used Forster resonance energy transfer (FRET) to study specific conformational changes in the Escherichia coli 30 S ribosomal subunit that occur upon association with the 50 S subunit. By measuring energy transfer between 13 different pairs of fluorescent probes attached to specific positions on 30 S subunit proteins, we have monitored changes in distance between different locations within the 30 S subunit in its free and 50 S-bound states. The measured distance changes provide restraints for modeling the movement that occurs within the 30 S subunit upon formation of the 70 S ribosome in solution. Treating the head, body, and platform domains of the 30 S subunit as simple rigid bodies, the lowest-energy solution converges on a model that satisfies each of the individual FRET restraints. In this model, the 30 S subunit head tilts towards the 50 S subunit, similar to the movement found in comparing 30 S subunits and 70 S ribosomes from X-ray and cryo-electron microscope structures, and the platform is predicted to undergo a clock-wise rotation upon association.

• 出版日期2005-11-25