Figure 1

Methylation of homeologous loci in Tragopogon miscellus. Sequence polymorphisms between the diploid parents (Tragopogon dubius and T. pratensis) were used to determine homeolog-specific silencing in T. miscellus allopolyploids. (a) Diagrammatic illustration of the expected chromatogram peaks for genomic and bisulfite-converted sequences when un-methylated or methylated in allopolyploid T. miscellus. This example shows silencing of the T. dubius homeolog. (b) Chromatograms of TDF-44 indicating the position of a methylated CG adjacent to a polymorphic site (red box) in T. miscellus compared to the diploids. (c) Chromatograms of S18 showing an un-methylated CG site in T. miscellus (black box) and the location of a polymorphic site between parental copies (red box). Red, blue, green and yellow colors of the chromatogram correspond to A, C, T and G, respectively. IUPAC ambiguity codes: W = A/T, Y = C/T, R = A/G. BS-converted = bisulfite-converted.