This Solar-Powered Sea Slug Steals Genes from Algae It Eats to Photosynthesize
by Owen James Burke
When the eastern emerald elysia has trouble finding food, it makes like a leaf and resorts to the sun, which can sustain it for months. Photo: redOrbit
The eastern emerald elysia (Elysia chlorotica) can live for up to 9 months at a time “feeding” on lipids and carbohydrates generated by sunlight all thanks to the algae it eats, new research in The Biological Bulletin concludes.
“There is no way on earth that genes from an alga should work inside an animal cell. And yet here, they do,” says Sidney K. Pierce, study co-author and emeritus professor at the University of South Florida and the University of Maryland, College Park. “They allow the animal to rely on sunshine for its nutrition. So if something happens to their food source, they have a way of not starving to death until they find more algae to eat.”
Photo: Patrick Krug
The verdant-green sea slug takes genes from the alga V. litorea, which researchers discovered in the slug’s chromosomes using advanced imaging.
Since the 1970s it has been known that the slug takes chloroplasts from the alga (called kleptoplasty), but they didn’t really know how until now. To date, this mucousy master of adapation is still the only known multicellular organism capable of consuming and repurposing the organelles of another.
Scientists are still baffled at how the slug can maintain the chloroplasts for up to 9 months (much longer than even the alga itself can manage them).
Evolution is at play, because the gene is transmitted to the next generation, though the slug still has to consume the alga in order for the chloroplasts to function. “When a successful transfer of genes between species occurs, evolution can basically happen from one generation to the next,” and not necessarily over thousands of years as is more generally the case, Pierce explains.
Pierce also pointed out that although the slug may not be a perfect biological model for human therapy, it could lead to further research in gene transfer.
Read more at the blog of Marine Biology Laboratory — OJB