Figure 2
From: Hydrocoel morphogenesis forming the pentaradial body plan in a sea cucumber, Apostichopus japonicus
Overall morphology of the developing hydrocoel lobes. (a–d) Whole embryos under the microscope (ventral view, anterior to the top) from phase 1 to phase 4. (a’–d’) show the hydrocoel of a-d. The dotted lines in (a–d) indicate the region shown in (a’–d’). The hydrocoel of the specimens stained with DAPI is shown in (a’’–d’: z-stack images) and (a’’’–d’’’: optical sections). In phase 1, the hydrocoel was spindle shaped and then extended up to 100 µm along the longitudinal axis in phase 2. The hydrocoel lobes started to form in phase 3, and the lobes extended in phase 4. During phases 1 and 4, no significant change in the overall morphology of entire larvae other than the change in the hydrocoel was observed.
