Ribosomal Protein L11: A Cog in the Nanomachine

Abstract

Comprised of two major subunits of both rRNA and proteins, the ribosome is a biological nanomachine, acting as the central player in the process of protein translation. Recent advances in molecular imaging have enabled the visualization of the disparate functional centers within the ribosome, leading to the question of how these critical regions coordinate their actions and communicate with each other. This work examines the essential ribosomal protein L11, located in the central protuberance of the large subunit. L11 maintains connections with the 5S rRNA, H84 of the 25S rRNA, comes in close proximity to the T-loop of the bound peptidyl tRNA, and shares an intersubunit bridge with small subunit protein S18. L11 was found to have a critical dynamic loop which samples the occupancy status of the P-site pocket of the ribosome and communicates this information through H84. L11's intersubunit bridge (the B1b/c bridge) mediates an intersubunit communication network from the decoding center to the peptidyl transferase center of the ribosome. L11 is also involved in proper subunit joining. Mutations in L11 were found to have effects on A- and P-site tRNA binding, translational fidelity, and growth and viability of yeast cells.