Nematostella Vectensis Resistance to Their Own Neurotoxin: Exploring the Coevolutionary Resistance of Ion Channels to Neurotoxins in Venomous Animals
Nematostella vectensis (Starlet Sea Anemone) has provides valuable insights into the evolution of nervous system development and excitability. For example, Nematostella has all types of voltage-gated K+ channels (Kvs) found in higher animals, demonstrating that these critical regulators of neuronal excitability evolved prior to the divergence of cnidarians and bilaterians roughly 600 million years ago. It is also well known that anthozoans such as Nematostella contain diverse voltage gated potassium channel (Kv) toxins in venoms that they use to paralyze prey or defend themselves in their natural habitats. This raises the question of whether anthozoans have developed resistance to their own toxins at the level of the channel targets themselves. To test this, we are examining whether Nematostella Shaker family Kv channels are resistant to a Shaker-like 2 toxin (Shkl2) present in their own venom. We expressed the Nematostella Shaker channels in Xenopus oocytes to expose them to Shkl2 to assess functional block using two electrode voltage clamp. Results obtained from this experiment suggest resistance in two different Nematostella shaker channels (NvKv1 and NvKv2) to Shkl2 which provides insight into the co-evolution of toxins and their target channels in venomous anthozoans.