|Del Valle-Echevarria, Angel -|
Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 6, 2012
Publication Date: November 9, 2012
Citation: Del Valle-Echevarria, A.R., Havey, M.J. 2012. Next-generation sequencing reveals deletions in mitochondrial mutants [abstract]. Plant and Animal Genome Conference. P0242. Technical Abstract: Cucumber mitochondria have three unique characteristics: paternal transmission, huge genome size, and mitochondrially encoded mosaic phenotypes. The cucumber mitochondrial DNA at 1.6 Mb is one of largest among angiosperms, and is divided into three chromosomes of 1.5 Mb, 84 Kb and 45 Kb. Paternally transmitted mitochondrial mutants show strongly mosaic (MSC) phenotypes on cotyledons and true leaves, slow growth and low germination rates. The Roche 454 platform was used to sequence purified mitochondrial DNAs from the highly inbred line ‘B’ and three MSC lines (MSC3, MSC12 and MSC16) independently derived from inbred B. Reads were aligned to the mitochondrial assembly of the cucumber cultivar ‘Calypso’. Compared to B and Calypso, the MSC lines had five deleted regions in the 1.5 Mb chromosome. The 85 kb chromosome was completely absent in MSC12 and MSC16 and approximately one-half was present in MSC3. None of the three MSC lines possessed identical deletions, indicating that they do not trace back to the same sublimon in inbred B. Quantitative PCR supported the sequence assemblies and indicated that the MSC phenotypes result from unique deletions in their mitochondrial DNAs.