ABSTRACT
New data are continuously shedding light on mitochondrial evolution. This concept involves two hypotheses on the origin of mitochondria. One proposes that the mitochondrion originated after the eukaryotic cell arose (endosymbiotic hypothesis); the other proposes that this organelle had its beginning at the same time as the cell (autogenous hypothesis). The endosymbiotic hypothesis hinges on the idea that mitochondria were originally prokaryotic cells capable of implementing oxidative mechanisms that later became endosymbionts. The autogenous hypothesis proposes that mitochondria split off from a portion of DNA in the nucleus of the eukaryotic cell [3]. The endosymbiotic hypothesis, initially proposed by
Introduction .............................................................................................................................................. 79 Origin of Mitochondria: Endosymbiotic Theory ..................................................................................... 79 Mitochondrial Functions: More Than ATP .............................................................................................. 80
Oxidative Stress .................................................................................................................................. 81 Mitochondrial DNA: Characteristics ....................................................................................................... 81 Mitochondrial DNA: Inheritance and Bottleneck Selection .................................................................... 83 Mitochondrial Replication and mtDNA Replication ............................................................................... 83 Early Mitochondrial Number and Morphology Changes ........................................................................ 85 Early Embryo Development Mitochondrial Metabolism ......................................................................... 85 Mitochondrial Function in the Early Embryo .......................................................................................... 86
Oxidative Stress and Early Embryo Development .............................................................................. 86 Mitochondrial Ca2+ Signaling and Fertilization .................................................................................. 86
Mitochondria as a Stress Sensor .............................................................................................................. 87 Mitochondria in Embryonic Implantation and Development .................................................................. 88 References ................................................................................................................................................ 89
Lynn Margulis, is the most widely accepted and exciting concept. It established the idea that mitochondria evolved from free-living bacteria via symbiosis within a eukaryotic host cell [4,5].
