PT  - JOURNAL ARTICLE
AU  - Boersma, Sanne
AU  - Khuperkar, Deepak
AU  - Verhagen, Bram M.P.
AU  - Sonneveld, Stijn
AU  - Grimm, Jonathan B.
AU  - Lavis, Luke D.
AU  - Tanenbaum, Marvin E.
TI  - Multi-color single molecule imaging uncovers extensive heterogeneity in mRNA decoding
AID  - 10.1101/477661
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 477661
4099  - http://biorxiv.org/content/early/2018/11/24/477661.short
4100  - http://biorxiv.org/content/early/2018/11/24/477661.full
AB  - mRNA translation is a key step in decoding genetic information. Genetic decoding is surprisingly heterogeneous, as multiple distinct polypeptides can be synthesized from a single mRNA sequence. To study translational heterogeneity, we developed the MoonTag, a new fluorescence labeling system to visualize translation of single mRNAs. When combined with the orthogonal SunTag system, the MoonTag enables dual readouts of translation, greatly expanding the possibilities to interrogate complex translational heterogeneity. By placing MoonTag and SunTag sequences in different translation reading frames, each driven by distinct translation start sites, start site selection of individual ribosomes can be visualized in real-time. We find that start site selection is largely stochastic, but that the probability of using a particular start site differs among mRNA molecules, and can be dynamically regulated over time. Together, this study provides key insights into translation start site selection heterogeneity, and provides a powerful toolbox to visualize complex translation dynamics.