Proteolytic breakdown of membrane-associated polypeptides in mitochondria of Saccharomyces cerevisiae

This chapter discusses the experimental procedures for studying this proteolytic breakdown that might represent a useful model system to understand the degradation of membrane-associated polypeptides. The analysis of this process in mitochondria is greatly facilitated by the availability of an in vitro system that allows the synthesis of mitochondrially encoded polypeptides to be carried out in isolated organelles independent of cytoplasmic factors. This in vitro system and its application in studies on the proteolysis of mitochondrial translation products are described in the chapter. The chapter concludes with the discussion of the characterization of the proteolytic system in the inner mitochondrial membrane. The availability of an in vitro system has allowed the biochemical characterization of the degradation of membrane-associated mitochondrial translation products. The proteolytic breakdown requires the hydrolysis of Adenosine triphosphate (ATP). © 1995 Elsevier Inc.