Figure 2.

The electroporation procedure for jellyfish eggs. (A) Schematic of spawning under the 24 h light/dark cycle. Clytia hemisphaerica are maintained on a 13 h dark/11 h light cycle. After light stimuli, sperm spawning occurs within 60–90 min and egg spawning occurs within 90–120 min. Cladonema pacificum are maintained on a 23.5 h light/0.5 h dark cycle. After dark stimuli, sperm and egg spawning occurs within 25 min. (B) Fertilized eggs are resuspended in 15% Ficoll/artificial sea water to prevent precipitation of eggs during electroporation. (C) Electroporation is performed with the Bio-Rad Gene Pulser Xcell electroporation system and a cuvette with a 4 mm gap. (D) Visualization of the Rhodamine-Dextran delivery into eggs by electroporation. Rhodamine is shown in red. While little or no fluorescence was observed in eggs without electroporation (No EP), under the condition of a single 50 V pulse for 25 ms, rhodamine signals were detected in both Clytia and Cladonema eggs without cell damage. For clarity, egg outlines are indicated with dashed lines for eggs without electroporation. Scale bars: 200 µm.