Figure 10. SpAGS but not EtAGS and PmAGS can induce a functional ACD in pencil urchin (Et) embryos.

A, Representative brightfield images of Et embryos with or without micromere-like cells. Black arrowhead indicates micromere-like cells. B, Et embryos were injected with 0.3μg/μl stock of GFP-AGS mRNAs and 1μg/μl stock of Vasa-mCherry mRNA. The number of embryos making micromere-like cells was scored and normalized to that of the Vasa-mCherry only. Statistical analysis was performed against Vasa-mCh only by One-Way ANOVA. C, Representative 2D-projection images of the injected Et embryos. Z-stack images were taken at 1μm intervals to cover a layer of the embryo. White arrowheads indicate micromere-like cells. Scale bars=10μm. D, The number of embryos showing Vasa enrichment in the micromere-like cells was scored and shown in %. Only the embryos that formed micromere-like cells were scored. Statistical analysis was performed against Vasa-mCh only by One-Way ANOVA. E, % of total embryos showing co-enrichment of Vasa and AGS in the micromere-like cells. Statistical analysis was performed against GFP-SpAGS by One-Way ANOVA. F-G, Representative 2D-projection images of Et embryos at 1 dpf. White arrowhead indicates Vasa enrichment in germ cells. Z-stack images were taken at 1μm intervals. % of total embryos showing Vasa enrichment in germ cells at 1 dpf was scored. Et embryos were injected with 0.3μg/μl stock of GFP-AGS mRNAs. Statistical analysis was performed against Vasa-mCh only by One-Way ANOVA. n indicates the total number of embryos scored. * represents p-value < 0.05, and ** p-value < 0.01. Each experiment was performed at least three independent times. Error bars represent standard error. Scale bars=20μm.