Involved in resistance to B.thuringiensis pore-forming toxin Cry5B downstream of the sek-1 and pmk-1 MAPK kinase pathway. By B.thuringiensis pore-forming toxin Cry5B. RNAi-mediated knockdown causes variable hypersensitivity to low, chronic doses of the B.thuringiensis pore-forming toxin Cry5B but not to heavy metal Cd(2+) exposure. Belongs to the arrestin family.