Plays a role in the stress response to heavy metals such as copper, probably in a fos-1/kgb-1-dependent manner. Weakly expressed in the intestine, but expression is up-regulated in response to Cu(2+). By heavy metal stress conditions, in response to Cu(2+). RNAi-mediated knockdown results in partial sensitivity to Cu(2+) ions with only 60% of animals reaching adulthood 4 days after egg laying.