Meeting Abstract
Echinoderms reproduce sexually as adults, but can reproduce asexually in the larval stage by cloning. Stressors, such as the presence and perceived presence of a predator, variations in food availability, and variations in temperature conditions have been found to cause larval cloning. Cloning may represent a way to overcome adverse conditions by generating another larva to the pelagic zone. This mechanism could allow for increased larval survival and increased chances of metamorphosis, benthic settlement, and reproduction. When a larva clones, it reproduces and increases its fitness before reaching sexual maturity in the adult stage. If cloned larvae are able to clone themselves and produce viable offspring, this would represent an increased larval population size and longer planktonic duration. This possibility represents a novel feature of the larval life stage, the potential to survive difficult environments and eventually develop into benthic adults. While cloning plays an important role in the larval life history, the molecular mechanism(s) behind it is unknown. In regeneration studies, the wnt pathway is known to be a key signaling molecule. We hypothesized that the wnt pathway also has a role in cloning. Using lithium chloride to inhibit glycogen synthase kinase 3β and activate the wnt pathway, we provide a reliable method to induce cloning in Dendraster excentricus larvae. Antibody staining of DAPI and β-catenin show β-catenin localization into the nucleus and activation of the wnt pathway in the larvae. Our results allow for increased laboratory research in echinoderm cloning now that clones can be produced reliably.
