During translation, what is displaced by the moving ribosome?

During translation, the ribosome moves along the mRNA strand, facilitating the synthesis of a polypeptide chain. As the ribosome advances, it displaces the Exon Junction Complex (EJC). The EJC is a protein complex that is assembled on mRNA after the splicing of introns, playing a crucial role in mRNA stability, export from the nucleus, and the regulation of translation.

As the ribosome moves, it interacts with the mRNA at the junctions of exons, effectively pushing the EJC aside. This displacement ensures that only those portions of the mRNA that are currently being translated remain associated with the ribosome, allowing the translation process to proceed smoothly without interference from the EJC.

In contrast, the other components listed are involved in different aspects of mRNA management and protein synthesis but are not directly displaced by the ribosome's movement during translation. For example, Poly-A binding proteins function in the stabilization of the mRNA and regulation of its translation, while eukaryotic initiation factors are important at the beginning stages of translation rather than during the elongation phase where ribosomal movement occurs. The mRNA tail, consisting of the poly-A tail, also does not get displaced by the rib