Overview
- A study published Thursday reports that researchers at Friedrich Schiller University Jena located blastopore tissue in the comb jelly Mnemiopsis leidyi that acts like an embryonic organizer and can be removed and transplanted.
- Within the species, transplanting about 20-micrometre pieces of blastopore tissue into other comb jelly embryos produced a secondary body axis in the host embryo.
- The team then xenotransplanted comb jelly blastopore tissue into starlet sea anemone embryos and triggered formation of an extra mouth and pharynx, with stained donor cells shown to induce the host’s tissues to change fate.
- The authors report identifying a gene linked to organiser formation in the sea anemone and say the molecular activity resembles known axis-patterning signals, though they do not present a complete molecular pathway.
- Experts praise the technical feat but caution over the evolutionary claim that organizer-based patterning dates to the dawn of animals, noting uncertain animal family relationships and alternative explanations such as convergence and differing molecular mechanisms.