ASNA1 (also known as TRC40) is a highly conserved ATPase involved in efflux of arsenite and antimonite. Reduced ASNA1 expression is associated with significant inhibition of cell growth,increased apoptosis and increased sensitivity to cisplatin and arsenite.Thus ASNA1 is proposed to be a target to overcome resistance to cancer chemotherapy. In addition,ASNA1 has been identified as an ER targeting factor for tail-anchored proteins in the posttranslational membrane insertion pathway.