Bcl-2 Is Located Predominantly in the Inner Membrane and Crista of Mitochondria in Rat Liver

• Published in: Biochemical and biophysical research communications 1998-08, Vol.249 (3), p.628-636
• Main Authors: Motoyama, Satoru, Kitamura, Michihiko, Saito, Satoshi, Minamiya, Yoshihiro, Suzuki, Hiroyuki, Saito, Reijiro, Terada, Kunihiko, Ogawa, Junichi, Inaba, Hideo
• Format: Article
• Language: English
• Subjects: Animals; Cell Fractionation; HL-60 Cells; Humans; Intracellular Membranes - metabolism; Intracellular Membranes - ultrastructure; Male; Microscopy, Immunoelectron; Mitochondria, Liver - metabolism; Mitochondria, Liver - ultrastructure; Proto-Oncogene Proteins c-bcl-2 - metabolism; Rats; Rats, Sprague-Dawley; Submitochondrial Particles - metabolism; Submitochondrial Particles - ultrastructure
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1998.9205

Bcl-2 is now recognized as a potent inhibitor of apoptotic cell death. It has been reported that Bcl-2 is located in the mitochondria, endoplasmic reticulum, and nuclear membrane in some cell lines, and it is not expressed in normal human and rat liver. An earlier study showed that Bcl-2 is an inner mitochondrial membrane protein. On the contrary, the following investigations using immunoelectron microscopy demonstrated that Bcl-2 resides predominantly in the mitochondrial outer membrane. In this study, using a cryo-sectioning immunogold labeling technique and immunoblotting, we carefully determined the subcellular localization of Bcl-2. Here we report that Bcl-2 is expressed in normal rat liver, and it is located predominantly in the inner membrane and crista rather than in the outer membrane of mitochondria.