||Fruit fly Drosophila melanogaster
||Garcia HG, Tikhonov M, Lin A, Gregor T. Quantitative imaging of transcription in living Drosophila embryos links polymerase activity to patterning. Curr Biol. 2013 Nov 4 23(21):2140-5. doi: 10.1016/j.cub.2013.08.054. p.2140 right column bottom paragraphPubMed ID24139738
||S.C. Little, M. Tikhonov, T. Gregor Precise developmental gene expression arises from globally stochastic transcriptional activity Cell, 154 (2013), pp. 789–800 doi: 10.1016/j.cell.2013.07.025.PubMed ID23953111
||P.2140 left column 2nd paragraph:"[Investigators’] technique allows for in vivo monitoring of nascent mRNA transcripts using a DNA sequence that upon transcription forms an mRNA stem loop. Cassettes with multiple copies of the stem loop are bound specifically by a constitutively expressed protein fused to GFP resulting in spatially localized fluorescence (Figure 1A). Using this technique, [investigators] examine the step-like expression of the Bicoid (Bcd) activated hunchback (hb) P2 enhancer and promoter (Figures S1A and S1B available online), one of the best-studied expression patterns in the fly embryo [refs 14, 15]."
||p.2140 right column bottom paragraph:"[Investigators] link the transcriptional dynamics of the 5’ construct to the emergence of the macroscopic pattern, whose formation results from the accumulation of cytoplasmic mRNA transcripts with a half-life of over 3 hr [ref 19] (in comparison, endogenous hb [hunchback] transcripts are stable for ~60 min [primary source])."