Calitoxin is a highly potent neurotoxin produced by the sea anemone Calliactis parasitica, which is stored in the nematocysts of stinging cells (cnidocytes).

They also published details on the toxin's effects in vitro on crustacean tissue preparations, including nerve and muscle.

The patterning of cleavage sites targeted during maturation of the peptide suggest that the active quaternary structure might be a tetrapeptide.

[3] Calitoxin and other sea anemone toxins are used in studying ion channels, with potential applications in biomedical and physiology research.

[7][3] In the mature CLX, one base-pair substitution is responsible for a single glutamic acid to lysine replacement in the coding region of CLX-2, leading to the difference between the two isoforms.

[1] Calitoxin has a very different sequence from another sodium channel binding sea anemone toxin, ATX-II, which is produced by the distantly related Anemonia sulcata.

[1] Despite markedly dissimilar gene sequences, CLX-1 affects crustacean axon potentials similar to two other classes of anemone toxins.

The minimum dose of 0.2 μg of toxin triggered muscle contractions in the crab, causing paralysis within 1 minute.

[10] In return for the protection, the sea anemone gains an advantage in accessing a broader distribution of food sources, as the crab moves across the ocean floor.