TY - JOUR T1 - Dynamics of <em>hunchback</em> translation in real time and at single mRNA resolution in the <em>Drosophila</em> embryo JF - bioRxiv DO - 10.1101/2021.02.16.430474 SP - 2021.02.16.430474 AU - Daisy J. Vinter AU - Caroline Hoppe AU - Thomas G. Minchington AU - Catherine Sutcliffe AU - Hilary L. Ashe Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/02/22/2021.02.16.430474.abstract N2 - The Hunchback (Hb) transcription factor is critical for anterior-posterior patterning of the Drosophila embryo. Despite the maternal hb mRNA acting as a paradigm for translational regulation, due to its repression in the posterior of the embryo, little is known about the translatability of zygotically transcribed hb mRNAs. Here we adapt the SunTag system, developed for imaging translation at single mRNA resolution in tissue culture cells, to the Drosophila embryo to study the translation dynamics of zygotic hb mRNAs. Using singlemolecule imaging in fixed and live embryos, we provide evidence for translational repression of zygotic SunTag-hb mRNAs. While the proportion of SunTag-hb mRNAs translated is initially uniform, translation declines from the anterior over time until it becomes restricted to a posterior band in the expression domain. We discuss how regulated hb mRNA translation may help establish the sharp Hb expression boundary, which is a model for precision and noise during developmental patterning. Overall, our data show how use of the SunTag method on fixed and live embryos is a powerful combination for elucidating spatiotemporal regulation of mRNA translation in Drosophila.Competing Interest StatementThe authors have declared no competing interest. ER -