title: Isolation of a single-stranded extrachromosomal DNA from germinating wheat embryos.
abstract: Newly-synthesized cytoplasmic non-mitochondrial DNA was isolated from wheat embryos which had been germinated in the presence of [14C]-thymidine for a time period not long enough to trigger the first post-dormant round of the nuclear DNA replication. This extrachromosomal DNA fraction consisted of linear single-stranded polydeoxyribonucleotide chains, corresponding in size to approximately 1.1 X 10(6) daltons, and amounted to about 0.5% of the total cellular DNA content. It is suggested that the appearance of the newly-synthesized polydeoxyribonucleotide chains in the cytoplasm may be a physiological signal for the initiation of the nuclear DNA replication in germinating wheat embryo cells.
mesh_terms: D002499:Centrifugation, Density Gradient; D002845:Chromatography; D003593:Cytoplasm / Q000032:analysis; D004277:DNA, Single-Stranded / Q000302:isolation & purification*; D005111:Extrachromosomal Inheritance; D006882:Hydroxyapatites; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D012639:Seeds / Q000032:analysis; D014908:Triticum / Q000235:genetics*
chemical_list: D004277:DNA, Single-Stranded; D006882:Hydroxyapatites; D010727:Phosphoric Diester Hydrolases