Fig. (2) Nutrients regulate the mitochondrial apoptotic machinery at multiple levels. Nutrients regulate Bcl-2 family proteins. Enforcement of glucose metabolism through overexpression of a glucose transporter plus hexokinase (HK) leads to maintenance of Mcl-1 and protection from Interleukin-3 withdrawal or Bim overexpression. Lack of glucose (glc, depicted as boiled sweets) activates p53, which can lead either to apoptosis mediated by induction of PUMA, or to cell growth arrest. Glucose deprivation also causes Bad dephosphorylation and Noxa-mediated apoptosis. Glucose withdrawal leads to induction of Bim, possibly mediated by the ER stress response. Amino acid withdrawal could also potentially lead to Bim induction as part of a CHOP-mediated ER stress response.