Cross-species amplification of microsatellite markers isolated from peach by means of heterologous primer pairs.

摘要

We have isolated and sequenced twenty-six microsatellites from two genomic libraries of peach (Prunus persica) cv. Redhaven, enriched for AC/GT and AG/CT repeats respectively. The enrichment procedure allowed to have as much as 50% of plaques containing the target repeat. We have assessed the cross-species transportability in Prunus, using DNA samples from seven different taxa out of peach (P. persica): nectarine (P. persica var. laevis), almond (P. dulcis), apricot (P. armeniaca), European plum (P. domestica), Japanese plum (P. salicina), sweet cherry (P. avium), and sour cherry (P. cerasus). Apple (Malus pumila) was also included in the sample. More than half (52%) of the microsatellites gave apparently correct amplification in all Prunus species surveyed, with bands within the range of expected sizes and compatible in the number with the known levels of ploidy. The remaining microsatellites gave less-extensive amplifications. The frequencies of lack of amplification were higher for species phylogenetically less related to peach, such as plums and cherries. The comparison of DNA sequences of the microsatellite UDP96-005, a complex microsatellite containing either AC/GT or AG/CT repeats, obtained by cloning and sequencing PCR products of all species but almond and sweet cherry, showed an almost perfect conservation across species of primer sequences designed on microsatellite flanking regions and the presence in all species of both CA and CT repeats.