Sea Anemones Evolving Toxins May be the Key to Medical Innovation

For years scientists have used the venom from many creatures to create medicines and treatments for various illnesses. To do this, scientists would extract venom from adult animals and then analyze the make up of the venom and use it in various ways. This process has always been done using adult animals, because the thinking was that an animals venom was the same at a larval stage as it would be at the adult stage. But a recent study with sea anemones has proved that theory wrong. Using a species of sea anemone, Nemotostella, also known as the Starlet Sea Anemone, researchers studied the venom development from larva to adult hood and how the venom chemically changes over the span of their developmental stages. Sea anemones being part of the Phylum Cnidaria have stinging cells on their tentacles that inject the venom into their prey called cnidocytes. To study the venom from these animals, researchers cultured these cells in various life stages and looked into the behavior of Nemotostella at each developmental stage.

Researchers began by studying the venom produced by larva Nemotostella. By analyzing the venom and watching the behavior of the larva, they observed that the venom produced at this stage seemed to be used for defense rather offense. As the small larva are floating through the water they are highly vulnerable to predators. The venom they produce helps them fend off predators so that they can grow to an adult. When a predator eats a larva, the larva release highly potent venom which makes the predator spit them out. This helps ensure that the larva can grow to adulthood and eventually reproduce.

Image of Nematosella 

As Nemotostella reaches adulthood its venom changes from that of a defense mechanism, to something to help them catch their prey. The venom chemically changes to better stun and kill potential prey, rather than surprise and disgust a potential predator. While researchers were surprised to find these changes, the changes did not stop with just development, the environment had an impact on the chemistry of the venom as well. As the water salinity, temperature, and food supply changed so did the potency and make up of the venom. This was a completely new aspect of the evolution of the sea anemone that researchers were excited to discover.  

Expression of Nematosella toxins 

The reason that this discovery is such a big breakthrough is due to the potential medical advancements that would be gained from studying the evolution of the Nematosella venom. Because most, if not all, research done on animal venom is venom taken from adult animals, the concept that there is a whole new variety of compounds from venom to look at has researchers thrilled. The possible new drugs, medicines and treatments that could come from studying these new compounds are unlimited. 

Cluster of Starlet Sea Anemones

Another question being asked in the scientific community after this discovery is how "normal" of behavior is it for animals to change their chemical composition as their environment changes? With climate change becoming a major issue around the world, not just for aquatic ecosystems but for terrestrial ecosystems as well, if scientists can study this further then perhaps they can understand ways to help other organisms change and adapt to an environment that otherwise would be lethal for them. This research could help millions of organisms have a brighter future in a harsher world. 

Resources: 

Image 3 : http://www.sars.no/research/SteinmetzGrp.php
Image 2: https://elifesciences.org/articles/35014

Image 1: 

ScienceDaily. Retrieved March 18, 2018 from 

www.sciencedaily.com/releases/2018/03/180305101633.htm


Yaara Y Columbus-Shenkar, Maria Y Sachkova, Jason Macrander, Arie Fridrich, Vengamanaidu Modepalli, Adam M Reitzel, Kartik Sunagar, Yehu Moran. Dynamics of venom composition across a complex life cycle. eLife, 2018; 7