title: Rapid divergence of repetitive DNAs in Brassica relatives.
abstract: Centromeric, subtelomeric, and telomeric repetitive DNAs were characterized in Brassica species and the related Raphanus sativus and Arabidopsis thaliana. In general, rapid divergence of the repeats was found. The centromeric tandem satellite repeats were differentially distributed in the species studied, suggesting that centromeric repeats have diverged during the evolution of the A/C and B genome lineages. Sequence analysis of centromeric repeats suggested rapid evolution. Pericentromere-associated retrotransposons were identified and showed divergence during the evolution of the lineages as centromeric repeats. A novel subtelomeric tandem repeat from B. nigra was found to be conserved across the diploid Brassica genomes; however, this sequence was not identified in the related species. In contrast to previous studies, interstitial telomere-like repeats were identified in the pericentromeres of Brassica chromosomes, and these repeats may be associated with genomic stability. These results provide insight into genome evolution during polyploidization in Brassica and divergence within the Brassicaceae.
authors.affiliation: Department of Biological Science, College of Biological Science and Biotechnology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Dal-Hoe
authors.initials: DH
authors.lastname: Koo
authors.forename: Chang Pyo
authors.initials: CP
authors.lastname: Hong
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Batley
authors.forename: Yong Suk
authors.initials: YS
authors.lastname: Chung
authors.forename: David
authors.initials: D
authors.lastname: Edwards
authors.forename: Jae-Wook
authors.initials: JW
authors.lastname: Bang
authors.forename: Yoonkang
authors.initials: Y
authors.lastname: Hur
authors.forename: Yong Pyo
authors.initials: YP
authors.lastname: Lim
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D001937:Brassica / Q000235:genetics*; D002503:Centromere / Q000235:genetics; D019143:Evolution, Molecular; D018745:Genome, Plant; D042822:Genomic Instability / Q000235:genetics; D009149:Mustard Plant / Q000235:genetics; D031224:Raphanus / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D018626:Retroelements / Q000235:genetics; D016615:Telomere / Q000235:genetics
chemical_list: D018626:Retroelements