title: Longevity of 5-azacytidine-mediated gene expression and re-establishment of silencing in transgenic rice.
abstract: Epigenetic silencing of a bialaphos resistance (bar) gene in R1 progeny of a transgenic rice line was found to be meiotically stable since selfed (R2) progeny were also susceptible and the bar locus highly methylated. A high proportion of R2 seedlings germinated in the presence of 5-azacytidine (AzaC) were herbicide-resistant and also contained at least one unmethylated copy of the bar gene, further establishing the relationship between silencing and methylation. Restored bar gene expression was typically maintained for 20-50 days, but eventual methylation and silencing of the bar locus underscores the ability of the recipient genome to recognize and inactivate intrusive DNA.
authors.affiliation: Institute of Developmental and Molecular Biology, and Department of Biology, Texas A&M University, College Station 77843-3155, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Kumpatla
authors.forename: T C
authors.initials: TC
authors.lastname: Hall
mesh_terms: D001374:Azacitidine / Q000494:pharmacology*; D019470:Biolistics; D003433:Crosses, Genetic; D004351:Drug Resistance / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D006540:Herbicides / Q000494:pharmacology; D009943:Organophosphorus Compounds / Q000494:pharmacology; D012275:Oryza / Q000187:drug effects / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics*; D015183:Restriction Mapping; D013997:Time Factors
chemical_list: D006540:Herbicides; D009943:Organophosphorus Compounds; C003122:bialaphos; D001374:Azacitidine