我国西南部喀斯特森林特有濒危树种掌叶木新的微卫星分子标记的开发

Isolation of Novel Microsatellite Loci for Handeliodendron bodinieri ( Sapindaceae ) , An Endangered Tree Endemic to Karst Forest in Southwestern China

摘要:

采用基因组DNA富集文库法FIASCO(Fast isolation by AFLP of sequences containing repeats)从掌叶木(Handeliodendron bodinieri)基因组中分离和筛选了10个新的微卫星位点,进而对掌叶木茂兰自然分布居群的遗传多样性进行了分析。结果表明, 每个位点在30株掌叶木个体上的平均等位基因数(A)为3.5(3~5个),平均观察杂合度(H_O)为0.650(0.267~0.900),平均预期杂合度(H_E)为0.494(0.224~0.652)。每个位点的第一排除概率值P_r(Ex₁)为0.029~0.240,位点综合值为0.7496。单个位点的第二排除概率P_r(Ex₂)为0.123~0.419,位点综合值为0.9517。这些信息预示着这些微卫星标记可以为研究喀斯特特有濒危树种掌叶木的基因流及居群遗传结构提供有效的遗传工具。

Abstract:

Ten novel polymorphic microsatellite loci were developed and characterized for Handeliodendron bodinieri according to a modified genomic DNA enrichment protocol of FIASCO (Fast isolation by AFLP of sequences containing repeat). These SSR (simple sequence repeat) loci were used to examine genetic diversity of H. bodinieri in Maolan karst forests, Guizhou Province. The results showed that each locus displayed between 3 and 5 alleles. The observed heterozygosity ranged from 0.267 to 0.900 and expected heterozygosity varied between 0.224 and 0.652. The combined probabilities of paternity exclusion over all loci were 0.7496 for P_r(Ex₁) and 0.9517 for P_r(Ex₂), respectively. It suggested that these loci could provide a powerful tool in investigating the patterns of gene flow and population structure in natural populations of H. bodinieri.