Figure 1. Mutant heph embryos manifest suppression of the CNS development in the ventral region, a phenotype linked to excess canonical Notch signaling phenotype.

Expression of Hunchback, a well-known neuronal marker, was used to assess the CNS development. Hunchback expression in Notch null and gain-of-canonical Notch signaling (N^intra/NICD) embryos is shown in Figure S2. Suppressed neurogenesis phenotype became apparent as early as stage 9 (about four hours of embryogenesis) and was severe at stage 14–15 (about 14–16 hours of embryogenesis). Variation in the suppression of neurogenesis in heph embryos was observed, which is presumably due to variable maternal contribution. All embryos shown were from the same experiment and were processed identically.