Fig. 4. Defects in caudal lobe formation following injection of At-Delta dsRNA. (A,B) Time-lapse recording of live embryos derived from Achaearanea females injected with gfp (A) or At-Delta^EB (B) dsRNA. The time after the start of observation (early stage 5) is shown at the bottom of each image (hour: minute). CM cells and the emerging caudal region are indicated by arrows and brackets, respectively. In B, an unusual invagination is seen at the emerging caudal region. (C-E) Timecourse of phenotype expression in caudal lobe after dsRNA injection. Each graph refers to one female injected with gfp (C), At-Delta^EB (D) or At-Delta^HH (E) dsRNA. #1-8 are identification numbers of individual females. Each vertical bar indicates relative numbers of embryos exhibiting normal (blue), invagination (red), and non-specific (yellow) phenotypes in each egg sac. The number at the top of each bar indicates the total number of embryos examined. Not all egg sacs produced by the females are presented. Unfertilized eggs and embryos that did not form morphologically normal germ disc were excluded from analysis. `Non-specific' phenotypes, which are often observed even in embryos derived from untreated females, include shrinking, thickening and destruction of germ disc. The asterisks in #1/gfp, #3/At-Delta^EB and #7/At-Delta^HH indicate egg sacs used for Fig. 5. Scale bar: 100 µm. ex, extra-embryonic area.