title: Methylation of the S f locus in almond is associated with S-RNase loss of function.
abstract: 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.
authors.affiliation: Unidad de Hortofruticultura, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Av. Montañana 930, 50059, Saragossa, Spain, afernandezmarti@ucdavis.edu.
authors.forename: Angel
authors.initials: A
authors.lastname: Fernández i Martí
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Gradziel
authors.forename: Rafel
authors.initials: R
authors.lastname: Socias i Company
mesh_terms: D000483:Alleles; D001483:Base Sequence; D005075:Biological Evolution; D019175:DNA Methylation; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D057890:Epigenomics; D035264:Flowers / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D020868:Gene Silencing; D006239:Haplotypes; D008969:Molecular Sequence Data; D010641:Phenotype; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D027861:Prunus / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D012260:Ribonucleases / Q000235:genetics* / Q000378:metabolism; D060436:Self-Incompatibility in Flowering Plants / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins; D012260:Ribonucleases