Final answer:
EF-Tu binds to aminoacyl-tRNA and GTP, facilitating the tRNA's entry to the ribosome's A site, where GTP is hydrolyzed to GDP upon correct codon-anticodon pairing, after which EF-Tu-GDP dissociates to allow peptide bond formation.
Step-by-step explanation:
The interaction of EF-Tu with aminoacyl-tRNAs is crucial for protein synthesis during the elongation phase of translation. Specifically, EF-Tu binds to GTP and aminoacyl-tRNA, facilitating the entry of this complex into the A site of the ribosome. Upon correct base-pairing between the tRNA anticodon and the mRNA codon, EF-Tu hydrolyzes GTP to GDP and then dissociates from the aminoacyl-tRNA, allowing it to fully enter the ribosome's A site for peptide bond formation. Subsequently, EF-Tu-GDP is recycled back to EF-Tu-GTP with the help of another elongation factor, known as EF-Ts, readying it for another round of elongation. The process is highly energy-dependent, utilizing GTP for both the binding of aminoacyl-tRNA to the A site and later for the translocation of the newly formed peptidyl-tRNA from the A site to the P site.