Examination of processing of the rat liver mitochondrial F1-ATPase β subunit precursor protein by high-resolution 2D-gel electrophoresis

We report the one-step processing of the rat liver beta-F1-ATPase precursor protein, as examined by high resolution 2D-gel electrophoresis. Proteolytic cleavage of the positively charged mitochondrial targeting signal of the precursor promotes decreases in both the molecular weight (approximately 3 kDa) and the isoelectric point (approximate 0.2 pH unit) of the protein. The results obtained illustrate the usefulness of this technique, since it takes advantage of both results of the maturation process, for molecular characterization of the processing of mitochondrial precursor proteins.