RT Journal Article SR Electronic T1 Precision of readout at the hunchback gene JF bioRxiv FD Cold Spring Harbor Laboratory SP 063784 DO 10.1101/063784 A1 Jonathan Desponds A1 Huy Tran A1 Teresa Ferraro A1 Tanguy Lucas A1 Carmina Perez Romero A1 Aurelien Guillou A1 Cecile Fradin A1 Mathieu Coppey A1 Nathalie Dostatni A1 Aleksandra M. Walczak YR 2016 UL http://biorxiv.org/content/early/2016/07/14/063784.abstract AB The simultaneous expression of the hunchback gene in the multiple nuclei of the developing fly embryo gives us a unique opportunity to study how transcription is regulated in functional organisms. A recently developed MS2-MCP technique for imaging transcription in living Drosophila embryos allows us to quantify the dynamics of the developmental transcription process. The initial measurement of the morphogens by the hunchback promoter takes place during very short cell cycles, not only giving each nucleus little time for a precise readout, but also resulting in short time traces. Additionally, the relationship between the measured signal and the promoter state depends on the molecular design of the reporting probe. We develop an analysis approach based on tailor made autocorrelation functions that overcomes the short trace problems and quantifies the dynamics of transcription initiation. Based on life imaging data, we identify signatures of bursty transcription initiation from the hunchback promoter. We show that the precision of the expression of the hunchback gene to measure its position along the anterior-posterior axis is low both at the boundary and in the anterior even at cycle 13, suggesting additional post-translational averaging mechanisms to provide the precision observed in fixed material.