Relative abundance of NAD kinase (NADK) mRNA in INS-1 832/13 cells (A) and rat (B) and mouse (C) islets. ME1, -2, and -3, malic enzymes 1, 2, and 3; PC, pyruvate carboxylase; ICD1 and -2, isocitrate dehydrogenase 1 and 2; NNT, nicotinamide nucleotide transhydrogenase.