Unidad de Hortofruticultura, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Av. Montañana 930, 50059, Saragossa, Spain,
Plant Mol Biol. 2014 Dec;86(6):681-9. doi: 10.1007/s11103-014-0258-x. Epub 2014 Oct 18.
Self-compatibility in almond (Prunus dulcis) is attributed to the presence of the S f haplotype, allelic to and dominant over the series of S-alleles controlling self-incompatibility. Some forms of the S f haplotype, however, are phenotypically self-incompatible even though their nucleotide sequences are identical. DNA from leaves and styles from genetically diverse almond samples was cloned and sequenced and then analyzed for changes affecting S f -RNase variants. Epigenetic changes in several cytosine residues were detected in a fragment of 4,700 bp of the 5' upstream region of all self-compatible samples of the S f -RNases, differentiating them from all self-incompatible samples of S f -RNases analyzed. This is the first report of DNA methylation in a Rosaceae species and appears to be strongly associated with inactivation of the S f allele. Results facilitate an understanding of the evolution of self-compatibility/self-incompatibility in almond and other Prunus species, and suggest novel approaches for future crop improvement.
扁桃（Prunus dulcis）的自交亲和性归因于 Sf 单倍型的存在，该单倍型与控制自交不亲和性的 S 等位基因系列等位，且呈显性。然而，某些形式的 Sf 单倍型尽管其核苷酸序列相同，但表现出自交不亲和性。从遗传多样性的扁桃样本的叶片和花柱中分离出 DNA 并进行克隆和测序，然后分析影响 Sf-RNase 变体的变化。在 Sf-RNases 的 5'上游区域的 4700bp 片段中，检测到几个胞嘧啶残基的表观遗传变化，将它们与分析的所有 Sf-RNases 的自交不亲和样本区分开来。这是蔷薇科物种中 DNA 甲基化的首次报道，似乎与 Sf 等位基因的失活密切相关。研究结果有助于理解扁桃和其他李属物种中自交亲和/自交不亲和的进化，并为未来作物改良提出了新的方法。
