title: Promoter methylation and progressive transgene inactivation in Arabidopsis.
abstract: Agrobacterium-transformed Arabidopsis plants were generated and the stability of their T-DNA-encoded resistance to kanamycin was examined. Of seven families, each homozygous for a single insertion event, two showed progressive inactivation of resistance over four generations of inbreeding. Loss of resistance was associated with methylation of an Sst II site in the nos promoter of the kanamycin resistance gene. Treatment of plant roots from inactive lines with the demethylating agent 5-azacytidine restored the ability of such lines to form callus on kanamycin-containing media. These observations are consistent with the view that methylation is a factor in the progressive inactivation of transgenes in Arabidopsis.
authors.affiliation: Department of Genetics, University of Cambridge, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Kilby
authors.forename: H M
authors.initials: HM
authors.lastname: Leyser
authors.forename: I J
authors.initials: IJ
authors.lastname: Furner
mesh_terms: D004269:DNA, Bacterial / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D004275:DNA, Ribosomal / Q000235:genetics / Q000378:metabolism; D004351:Drug Resistance / Q000235:genetics; D007178:Inbreeding; D007612:Kanamycin / Q000494:pharmacology; D019868:Kanamycin Kinase; D008745:Methylation; D010770:Phosphotransferases / Q000235:genetics; D010944:Plants / Q000187:drug effects / Q000235:genetics*; D030821:Plants, Genetically Modified; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; C036483:T-DNA; D007612:Kanamycin; D010770:Phosphotransferases; D019868:Kanamycin Kinase