Submitted to: Cucurbitaceae Proceedings
Publication Type: Review Article
Publication Acceptance Date: October 3, 2010
Publication Date: November 14, 2010
Citation: Calderon, C., Al-Faifi, S., Bartoszewski, G., Malepzy, S., Havey, M.J. 2010. The Unique Mitochondrial Genetics of Cucumber. Cucurbitaceae Proceedings. p. 40-41.
Plant cells typically contain two organelles, plastids and mitochondria. For the vast majority of plants, both of these organelles are maternally transmitted. Cucumber and melon are exceptions to this rule because the mitochondria are paternally transmitted. These two plants also possess mitochondrial DNAs that are among the largest known for all plants and animals. The mitochondrial DNA of cucumber carries many short repetitive DNA motifs and recombination among these repeats produces highly rearranged mitochondrial DNAs, even among closely related plants. These mitochondrial rearrangements are associated with strongly mosaic (MSC) phenotypes. As a result, cucumber is a unique model for organellar genetics because the three plant genomes show differential transmission, i.e. maternal for plastid, paternal for mitochondrial and bi-parental for nuclear DNA, as well as the potential for production of mitochondrial mutants associated with specific DNA rearrangements. We are working to map a unique nuclear locus (Psm) that controls sorting of wild-type versus MSC mitochondria transmitted by the male gametophyte. Eventual cloning of Psm should provide unique insights about nuclear-mitochondrial interactions that control the prevalence of specific mitochondrial DNAs.