Analysis of Type II NAD(P)H Dehydrogenases.

Plant mitochondria contain at least four type II NAD(P)H dehydrogenases that link NAD(P)H oxidation to the inner membrane electron transport chain and bypass proton pumping at Complex I, hence ATP synthesis. These activities have been found in mitochondria isolated from all plant species analyzed to date. In this chapter, methods are presented to analyze the expression of genes encoding these dehydrogenases and to detect protein levels in mitochondria isolated from Arabidopsis (Arabidopsis thaliana). In addition, methods and assay conditions are presented to detect the activity of each of these four type II NAD(P)H dehydrogenases in isolated plant mitochondria.