At the inner mitochondrial membrane (IM), tafazzin (TAZ) converts monolysocardiolipin (MLCL) and phosphatidylethanolamine (PE) to cardiolipin (CL) and 1-acyl lysophosphatidylethanolamine (LPE) (Xu et al. 2003, Xu et al. 2006, Malhotra et al. 2009). Although this reaction is reversible, the net effect of the phospholipase A and acyltransferase reactions drives it towards the formation of LPE and CL.