The Role of Initiation Factor Dynamics in Translation Initiation

Like most biological polymerization reactions, ribosome-catalyzed protein synthesis, or translation, can be divided into initiation, elongation, and termination stages. Initiation is the rate-limiting stage of translation and a critical site for translational control of gene expression. Throughout all stages of protein synthesis, the ribosome is aided by essential protein co-factors known as translation factors. I have studied the role that two translation initiation factors, IF1 and IF3, play in the mechanism and regulation of translation initiation in Escherichia coli. Specifically, I have used single-molecule fluorescence resonance energy transfer (smFRET) as a primary tool for investigating how the dynamics of IF1 and IF3 regulate the accuracy with which the translational machinery selects an initiator transfer RNA (tRNA) and the correct messenger RNA (mRNA) start codon during the initiation stage of protein synthesis.