Leveraging genome-wide datasets to quantify the functional role of the anti-Shine–Dalgarno sequence in regulating translation efficiency

Hockenberry AJ, Pah AR, Jewett MC, Amaral LAN
Open Biology 7,  160239 (2017)
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Abstract

Studies dating back to the 1970s established that sequence complementarity
between the anti-Shine–Dalgarno (aSD) sequence on prokaryotic ribosomes
and the 5’ untranslated region of mRNAs helps to facilitate translation
initiation. The optimal location of aSD sequence binding relative to the
start codon, the full extents of the aSD sequence and the functional form of
the relationship between aSD sequence complementarity and translation efficiency
have not been fully resolved. Here, we investigate these relationships
by leveraging the sequence diversity of endogenous genes and recently available
genome-wide estimates of translation efficiency. We show that—after
accounting for predicted mRNA structure—aSD sequence complementarity
increases the translation of endogenous mRNAs by roughly 50%. Further,
we observe that this relationship is nonlinear, with translation efficiency
maximized for mRNAs with intermediate levels of aSD sequence complementarity.
The mechanistic insights that we observe are highly robust: we
find nearly identical results in multiple datasets spanning three distantly
related bacteria. Further, we verify our main conclusions by re-analysing a
controlled experimental dataset.