Previous work has identified multiple targets of artemisinin in the malaria parasite that are covalently modified by artemisinin31,32, but in these studies the artemisinin-derived probes were used at a concentration three orders of magnitude or more above the IC50 value of 0.3 nM for mammalian SERCA3 found in the present study, so the possibility of a more selective effect at lower concentrations of artemisinin cannot be excluded. The gene discussed is ATP2A3; the disease is malaria.