THE LIFE-CYCLE OF MITOCHONDRIA IN THE TRUE SLIME-MOLD, PHYSARUM-POLYCEPHALUM

The cytoplasmic aspects of mitochondrial biogenesis have been the focus of much recent attention and a review is presented here of studies on the life cycle of mitochondria in Physarum polycephalum. Such studies have focused predominantly on behavior of the mitochondrial genome throughout the mitochondrial life cycle and have been designed to reveal details about (1) the role of the DNA-membrane complex in the segregation of the mitochondrial genome; (2) the regulation of mitochondrial activity associated with changes in ploidy of the mitochondrial nucleus; (3) the hierarchical pattern of transmission of the mitochondrial genome as it relates to the mating-type locus (matA) during the sexual development; and (4) the fusion of mitochondria that is promoted by a mitochondrial plasmid. The results of such studies contribute significantly to efforts towards a better understanding not only of the mitochondrial life cycle in P. polycephalum but also of the biogenesis of mitochondria and plastids in many other organisms.