Triplet-Repeat Microsatellites Shared Among Hard and Soft Pines

Abstract

Vascular plant species have shown a low level of microsatellite conservation compared to many animal species. Finding trans-specific microsatellites for plants may be improved by using a priori knowledge of genome organization. Fifteen triplet-repeat microsatellites from hard pine (Pinus taeda L.) were tested for trans-specific amplification across seven hard pines (P. palustris Mill., P. echinata Mill., P. radiata D. Don., P. patula Schiede et Deppe, P. halepensis Mill., P. kesiya Royle), a soft pine (P. strobus L.), and Picea rubens Sargent. Seven of 15 microsatellites had trans-specific amplification in both hard and soft pine subgenera. Two P. taeda microsatellites had conserved flanking regions and repeat motifs in all seven hard pines, soft pine P. strobus, and P. rubens. Perfect triplet-repeat P. taeda microsatellites appear to be better candidates for trans-specific polymorphism than compound microsatellites. Not all perfect triplet-repeat microsatellites were conserved, but all conserved microsatellites had perfect repeat motifs. Persistent microsatellites PtTX2123 and PtTX3020 had highly conserved flanking regions and a conserved repeat motif composition with variable repeat unit numbers. Using trinucleotide microsatellites improved trans-specific microsatellite recovery among hard and soft pine species.

Development and characterization of polymorphic microsatellite markers for the sweet orange (Citrus sinensis L. Osbeck)

“…According to Kutil and Williams (2001) compound microsatellites are less persistent than perfect microsatellites because the former contain more imperfections and deletions and probably represent the last stage before degradation. Perfect microsatellites were the most frequent type in our study, followed compound and the imperfect microsatellites, and this suggests a certain degree of sequence stability and conservation in their recent evolution, although it is also possible that the use of enriched libraries may have enhanced the number of perfect microsatellites (Moriguchi et al, 2003).…”

“…Plant microsatellites have been developed for germplasm conservation, cultivar identification and for assessing genetic diversity not only in crops such as tomato (He et al, 2003a) and peanut (He et al, 2003b;Ferguson et al, 2004) but also in marijuana (Alghanim and Almirall, 2003) and perennial plants such as the Melaleuca (the tea tree) (Rossetto et al, 1999), Pinus (Kutil and Williams, 2001), Cryptomeria (Moriguchi et al, 2003) and Litchi Genetics and Molecular Biology, 29, 1, 90-96 (2006) Copyright by the Brazilian Society of Genetics. Printed in Brazil www.sbg.org.br (Viruel and Hormaza, 2004).…”

Pine microsatellite markers allow roots and ectomycorrhizas to be linked to individual trees

“…Further work is required to test whether three loci would suffice to identify all individuals from a larger population of host trees. However, if the three primer pairs used in this study were found to be insufficient at discriminating between larger populations of pine trees, a number of alternative microsatellite primers are available (Kutil & Williams, 2001; (Smith et al, 1965;Moser, 1997). We have a sequence from a basidiome of S. flavidus (AY641461) collected in NE Scotland which is 99.2% similar over 645/653 bp with L54115, indicating that S. umbonatus should indeed be regarded as a synonym of S. flavidus.…”

Transpecific microsatellites for hard pines

“…Similarly, transfer to other subgenera or nonPinus coniferae has been reported to be poor (Echt et al 1996;Fisher et al 1998), although optimisation of polymerase chain reaction (PCR) conditions increased transfer rates for some of these loci (Karhu et al 2000). Kutil and Williams (2001) reported that tri-nucleotide microsatellites from low-copy genomic regions increased transfer rates within Pinaceae. Unlike previous investigators, they noted that both flanking regions and repeat motifs were highly conserved in soft and hard pines.…”