Figure 3

Gene reporter assays reveal the temporal dynamics driven by tested CRM. Right: Each CRM predicted by cisTargetX is schematically represented (see Additional file 1: Figure S2 for a detailed description). Vertical black lines represent evolutionarily conserved GCNF clusters as predicted by cisTargetX. Horizontal boxes summarize regions tested by transgenic assays. Left: Reporter activity was examined at different times after puparium formation (APF, indicated on top). A ventral and a dorsal view are shown in each case. Top: CG15545 was also analyzed using a GFP reporter (Figure 4) which serves as a control for βGal staining. No βGal expression is visible, except on pharate adults (96 h APF) in pericardiac cells, which indicate endogenous βGal activity in this tissue. 24 h APF: No βGal activity was observed, except in a few discrete tissues in CG3902-LacZ and CG10175-LacZ flies (respectively in the developing eye and in discrete spots at the basis of the head). 48 h APF: In all LacZ transgenic lines, reporter construct induce βGal expression in a variety of tissues (weak staining was occasionally observed at 42 h, not shown). a: antennae, e: eye, h: head, l: legs, m: muscles, w: wings. 72 h APF: Maximum βGal activity was observed around this time point. 96 h APF: X-Gal staining in pharate adults is due to stability of βGal, since no expression at this stage was observed on GFP-reporter constructs (see Figure 4).