MTOR and fetal growth restriction: We previously reported that mTOR signaling and placental system A amino acid transport activity in the same human IUGR cohort placenta used in the current study were reported to be downregulated.8 The protein expression of DEPTOR was significantly higher (P = .0001; AGA, n = 19; FGR, n = 25) in FGR placentas as compared to AGA (Figure 2A and B).