Location: Vegetable Crops Research Unit
Title: Genetic Analyses of Sorting of Paternally Transmitted Mitochondrial DNA Authors
|Calderon, Claudia -|
Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 20, 2009
Publication Date: January 7, 2010
Citation: Calderon, C.I., Havey, M.J. 2010. Genetic Analyses of Sorting of Paternally Transmitted Mitochondrial DNA [abstract]. Plant and Animal Genome Conference. p. 675. Technical Abstract: The organelles are maternally transmitted in the vast majority of eukaryotes. However paternal transmission of plastids and mitochondria occurs rarely in plants. Cucumber is a unique model plant for organellar genetics because its three genomes show differential transmission: maternal for chloroplast, paternal for mitochondrial and bi-parental for nuclear. Furthermore there exist cucumber plants with a strongly mosaic (MSC) phenotype associated with rearrangement in the mitochondrial DNA. We identified a nuclear locus which sorts preferentially for rare sublimons in crosses with MSC plants as pollen donors. This unique locus is named Psm, for Paternal Sorting of Mitochondria. In order to fine map and eventually clone Psm we produced a segregating population of ~1000 gametes from the cross of Plant Introduction 401734 and Cucumis sativus var hardwickii. Using a combination of molecular approaches (agarose and polyacrylimyde gel electrophoresis, fluorescent fragment analysis and high resolution melt-curve analysis), we mapped Psm to chromosome 3 of cucumber and identified flanking SSR markers. Fine mapping of Psm to a specific genomic region will allow us to exploit the recently generated whole-genome sequence of cucumber to identify candidate genes for Psm. Eventual cloning of Psm will provide insights about nuclear control of organellar-DNA sorting.