Live-cell single RNA imaging reveals bursts of translational frameshifting

Kenneth Lyon; Luis U. Aguilera; Tatsuya Morisaki; Brian Munsky; Timothy J. Stasevich

The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. . https://doi.org/10.1101/478040 doi: bioRxiv preprint traffic jams would lead to longer run-off delays. Consistent with this, ribosomes within frameshifting sites took much longer to run-off (Fig. 4B) , with frameshifted ribosome levels fluctuating but remaining overall steady for upwards of 3000 s, despite an overall ribosome loss (Figs. S9 and S10). We observed this trend even at the single-molecule level, where the total number of ribosomes (marked by HA) dropped, but the number of Such a release can be seen in the single-molecule track at the ~1000 s time point, when the frameshift signal gets significantly brighter. Interestingly, this increase in brightness coincided with the association of an additional non-translating +FSS RNA (gray arrows in Fig. 4C ). This is consistent with the hypothesis that multi-RNA factories stimulate frameshifting. Although difficult to capture, we observed this type of stimulated frameshifting burst in another single frameshifting RNA track as well (Fig. S11 ).