NAD-dependent isocitrate dehydrogenase (IDH) is a Krebs cycle enzyme situated in mitochondria. InArabidopsis thaliana, five genes encode functional IDH subunits that can be classed into two groups based on gene structure and subunit amino acid sequence. Arabidopsis contains two catalytic and three regulatory subunits according to their homology with yeast IDH. IDH1 Performs an essential role in the oxidative function of the citric acid cycle.
