Figure 6

Uri is on active chromatin in polytene chromosome spreads. A-F, Polytene chromosomes from wild type larvae stained for Uri (green), active RNAPII (red) and DNA (blue). Higher power single channel greyscale images of the boxed region are shown in A, B, and the merge of these is shown in C. Uri co-localises with active RNAPII on normal larval polytene chromosomes (A-C; overlap is yellow in C.). D-F, After heat shock, RNAPII activity is restricted to the heat-shock puffs (E), Uri co-localises to these puffs (D, F). G, RT-PCR of potential uri target genes from uri^110bhomozygous embryos and uri^110b/CyO GFP sibling control embryos. The results of three independent experiments are shown; size marker is shown on the left. mRNA levels of CG3999 and PP1β9C varied somewhat between experiments; CG3999 was slightly reduced in mutant compared to control embryos, PP1β9C on average was equal in mutant compared to control. CG1315 and ebony mRNA levels were significantly and reproducibly lower in the mutant embryos than in control embryos. GFP control primers confirm the accuracy of embryo selection based on fluorescence. Asterisks indicate primer dimer bands.