Figure 1
From: Control of endogenous gene expression timing by introns
Design and results of Hes7 In(-) and In(+) reporters studied by Takashima et al . [7]. The ubiquitinated luciferase (Ub-Luc) sequence tagged with either intronless In(-) or intron-containing In(+) Hes7 transcript sequence is placed under the control of the Hes7 promoter region (pHes7). From the mRNA, only the Ub-Luc sequence before the stop codon (red dot) is translated, and this is detected by luminescence imaging in vivo. In contrast to the In(-) reporter (a), the synthesis and processing of introns (dotted RNA segments) from the In(+) transcript introduce an additional delay into the expression timing of the In(+) reporter (b). Inset, the timing of Hes7 mRNA (black dashed line) and Hes7 protein (continuous black line) is compared with In(-) and In(+) luminescence reporter signals (green and yellow lines, respectively).