Native-DIGE: a new look at the mitochondrial membrane proteome.

Respiratory chain proteins play a pivotal role in mitochondrial metabolism and thereby in the aging process. Differential display of the mitochondrial proteome reveals the abundance changes occurring in proteins as response to complex events such as senescence and aging. However, there is an absolute need to implement a detection technique that could potentially encompass the hydrophobic and very basic membrane proteins, along with the soluble ones. It is also important to assess protein-protein interactions, besides changes in abundance. Native-difference gel electrophoresis (DIGE) is an approach that facilitates sensitive quantitative assessment of changes in membrane and soluble proteins. It stretches the boundaries of detecting abundance changes to protein-protein interactions for interpretation of a proteome in a more "meaningful" way. Here we evaluate the benefits of blue-native fluorescence DIGE as a method in differential quantitative proteomics with a focus on critical issues for application and experimental design.