Simulations and geometric analysis of the ribosome reveal precise single-molecule strategies for monitoring head dynamics during translocation

Abstract

The ribosome is a complex ribonucleoprotein machine that translates mRNA chains into polypeptide chains, which subsequently fold into proteins in all biological cells. The ribosome consists of a large subunit and a small subunit. The small subunit is further subdivided into a body domain and a head domain. The ribosome undergoes large-scale conformational changes during the elongation step of the process of translation. Structural studies and simulations reveal that the head domain undergoes coupled rotatory motions around multiple axes during mRNA-tRNA translocation.