Translation is a fundamental gene regulation mechanism crucial for all domains of life. During translation elongation, the anticodon of transfer RNA (tRNA) pairs with the corresponding codon on messenger RNA (mRNA) according to the reading frame at the ribosomal A site. However, this precise process can be disrupted under certain conditions, leading to a shift in the reading frame, known as frameshifting. This shift mainly occurs during the second phase of elongation, called translocation, which is facilitated by elongation factor G (EF-G). 

In this study, we focus on the translocation event, where mRNA-tRNA base pairs, initially located in the P and A sites of the ribosome, are translocated to the E and P sites, respectively, with the assistance of EF-G. To investigate whether frameshifting occurs, we employ specifically designed mRNA sequences encoding a frameshifting signal, along with tRNAs prone to frameshifting. Our goal is to understand how the mRNA-tRNA base pairs are stabilized within the ribosome following a frameshift in the mRNA reading frame. We will utilize cryogenic electron microscopy (cryo-EM) to observe this process at near-atomic resolution.

Literature:

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