Fig. 3

Maternal zygotic ezh2 mutants form a normal body plan and display a pleiotropic phenotype at 2 dpf.

(a) MZezh2^{hu5670/hu5670} appear relatively normal at 1 dpf, although a clear mid-hindbrain boundary appears to be absent (arrow head). They display a pleiotropic phenotype at 2 dpf, having small eyes, a stringy heart, and blood accumulation (arrow heads). MZezh2^hu5670/+ show normal development. (b) The pleiotropic phenotypes of MZezh2^{hu5670/hu5670} can be rescued by injection of full-length ezh2 mRNA (300 pg). The numbers indicate the number of embryos with the displayed phenotype compared to the total number of embryos injected in two experiments. (c) Expression analysis of ezh1 and ezh2 in wildtype and MZezh2^{hu5670/hu5670} embryos at 0 hpf, 3.3 hpf, and 1 dpf. Expression of ezh1 is not detectable in MZezh2^{hu5670/hu5670} embryos and wildtype embryos at 0 hpf, 3.3 hpf, and 1 dpf. ezh1 is expressed in wildtype control embryos at 5 dpf. ezh2 is expressed in wildtype embryos at 0 hpf, 3.3 hpf, 1 dpf, and 5 dpf, showing a decrease in expression over time. ezh2 expression cannot be detected in MZezh2^{hu5670/hu5670} embryos. Relative expression was calculated based on expression of housekeeping genes β-actin and ef1α. Error bars represent standard deviation. n.d. is not done. (d) In situ hybridization for eng1 (muscle pioneer marker) and myoD (somite marker) at 1 dpf in MZezh2^{hu5670/hu5670} embryos and MZezh2^hu5670/+. Both eng1 and myoD are normally expressed in MZezh2^{hu5670/hu5670} and MZezh2^hu5670/+. Scale bar is 500 µm. (e) In situ hybridization for ntl at 1 dpf shows no difference in spatiotemporal expression between MZezh2^{hu5670/hu5670} embryos and the heterozygous siblings. At 2 dpf in situ hybridization for ntl showed expression in the notochord of MZezh2^{hu5670/hu5670} embryos, whereas this is not visible in MZezh2^hu5670/+ (arrow head). In situ hybridization for krox20 at 1 dpf showed normal expression in MZezh2^hu5670/+, but reduced expression in rhombomeres 3 and 5 in MZezh2^{hu5670/hu5670} embryos (arrow heads). Scale bar is 500 µm for lateral views and 250 µm for dorsal view of krox20 expression. The numbers indicate the number of embryos with the displayed phenotype compared to the total number of embryos analyzed.