Mitochondria and peroxisomes are essential subcellular organelles in mammals. Despite obvious differences, both organelles display certain morphological and functional similarities. Recent studies have elucidated that these highly dynamic and plastic organelles share components of their division machinery. Mitochondria and peroxisomes are metabolically linked organelles, which are cooperating and cross‐talking. This review addresses the dynamics and division of mitochondria and peroxisomes as well as their functional similarities to provide insight as to why these organelles share the fission machinery in evolutionary aspects.© (...) 2007 Wiley Periodicals, Inc. (shrink)

The continuing viability of the free‐radical theory of ageing has been questioned following apparently incompatible recent results. We show by modelling positional effects of the generation and primary targets of reactive oxygen species that many of the apparently negative results are likely to be misleading. We conclude that there is instead a need to look more closely at the mechanisms by which free radicals contribute to age‐related dysfunction in living systems. There also needs to be deeper understanding of the dynamics (...) of accumulation and removal of the various kinds of molecular damage, in particular mtDNA mutations. Finally, the expectation that free‐radical damage on its own might cause ageing needs to be relinquished in favour of the recognition that the free‐radical theory is just one of the multiple mechanisms driving the ageing process. (shrink)