Assessment of cross-taxa utility of coconut microsatellite markers.

摘要

Microsatellites or simple sequence repeats (SSRs) are abundant across eukaryotic genomes and show high levels of polymorphism. Microsatellite DNA often has flanking regions that are highly conserved in related species and this renders the primer pairs designed in one species useful for the amplification of the same DNA region in related genomes, minimizing laborious cloning and screening steps. Studies were conducted to explore the transferability of coconut SSRs to other palms, i.e. oil palm (Elaeis sp.), arecanut (Areca catechu), palmyrah (Borassus sp.) and date palm (Phoenix dactylifera). The annealing temperature of 86 coconut-specific SSR primers was standardized using gradient PCR. Of the 86 primers, 55 primers gave clear bands of expected size range (100-300 bp) and these were tested for their cross-taxa amplification. The percentage of cross-amplification of coconut SSR loci were 36.36% in oil palm, 29.09% in arecanut, 18.18% in palmyrah and 12.70% in date palm. The results suggest the usefulness of coconut SSRs for phylogenetic and comparative genomic studies in other palms.