Essential structural elements in tRNAPro for EF-P-mediated alleviation of translation stalling
Abstract
The ribosome stalls on translation of polyproline sequences due to inefficient peptide bond formation between consecutive prolines. The translation factor EF-P is able to alleviate this stalling by accelerating Pro-Pro formation. However, the mechanism by which EF-P recognizes the stalled complexes and accelerates peptide bond formation is not known. Here, we use genetic code reprogramming through a flexible in-vitro translation (FIT) system to investigate how mutations in tRNAPro affect EF-P function. We show that the 9-nt D-loop closed by the stable D-stem sequence in tRNAPro is a crucial recognition determinant for EF-P. Such D-arm structures are shared only among the tRNAPro isoacceptors and tRNAfMet in Escherichia coli, and the D-arm of tRNAfMet is essential for EF-P-induced acceleration of fMet-puromycin formation. Thus, the activity of EF-P is controlled by recognition elements in the tRNA D-arm.
- Publication:
-
Nature Communications
- Pub Date:
- May 2016
- DOI:
- 10.1038/ncomms11657
- Bibcode:
- 2016NatCo...711657K