Anemone repair proteins as a potential therapeutic agent for vertebrate hair cells: facilitated recovery of the lateral line of blind cave fish.

Blind cave fish use the lateral line sensory system to detect nearby objects. The fish responds to sudden perturbations in the water column by initiating startle responses in which they swim more rapidly. Normal startle responses disappear after trauma caused by a single 15 s immersion in calcium free water, but return within 5 days if the traumatized fish are treated with 'repair proteins' isolated from sea anemones. Polyclonal antibodies raised to fraction beta, a specific chromatographic fraction of repair proteins, bind to hair cells within superficial neuromasts. Likewise, biotinylated fraction beta binds to hair cells in neuromasts. Neuromast hair cells exposed to calcium free water followed by repair proteins have more compact hair bundles than do hair cells exposed only to calcium free water. We propose that anemone repair proteins replace linkages between stereocilia destroyed by exposure to calcium free water.