Abstract
Cardiolipin (CL) is widely distributed in various prokaryotes and eukaryotes as a membrane phospholipid. CL has a dimeric sturucture and the phosphate groups of CL are negatively charged at neutral pH, thus, CL is classified as an anionic phospholipid. In eukaryotes, it is localized in the inner membrane and at sites of contact between the inner and outer membranes of mitochondria. Biochemical and molecular genetical studies have suggested that CL is involved in many processes and phenomena, such as stabilization of respiratory complex, apotosis, osmotic regulation, mitochondrial morphogenesis. However, the crucial role of CL has not been clarified. The recent identification of genes for enzymes that are required for the biosynthesis of CL in many organisms, as well as the subsequent generation of mutants defective in the biosynthesis of CL has provided molecular tools to dissect the functions of CL. In this review, we summarize the findings obtained by recent studies on the function of CL in prokaryotes and eukaryotes, and discuss the crucial role played by CL.
