Heterogeneous distribution and replication activity of mitochondria in Xenopus laevis oocytes.
In early diplotene oocytes of Xenopus laevis mitochondria are not dispersed all over the cytoplasm but gathered in a well described mitochondrial mass [18]. When tracing these organelles during active vitellogenesis we observe that some of them are involved in the elaboration of a cortical layer at the vegetative hemisphere of the cell while others stay around the nucleus. The latter contribute to the transient formation of a mitochondrial crown throughout active mitochondriogenesis. Autoradiographic studies of thymidine incorporation into mtDNA suggest a differential participation of each organelle to the final population of a full-grown oocyte according to its position in the cytoplasm.
D000818:Animals; D001345:Autoradiography; D004261:DNA Replication; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D008854:Microscopy, Electron; D008928:Mitochondria / Q000378:metabolism*; D009865:Oocytes / Q000502:physiology* / Q000648:ultrastructure; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014981:Xenopus
D004272:DNA, Mitochondrial; D014316:Tritium; D013936:Thymidine