title: Structure and dynamics of retrotransposons at wheat centromeres and pericentromeres.
abstract: Little is known of the dynamics of centromeric DNA in polyploid plants. We report the sequences of two centromere-associated bacterial artificial chromosome clones from a Triticum boeoticum library. Both autonomous and non-autonomous wheat centromeric retrotransposons (CRWs) were identified, both being closely associated with the centromeres of wheat. Fiber-fluorescence in situ hybridization and chromatin immunoprecipitation analysis showed that wheat centromeric retrotransposons (CRWs) represent a dominant component of the wheat centromere and are associated with centromere function. CRW copy number showed variation among different genomes: the D genome chromosomes contained fewer copies than either the A or B genome chromosomes. The frequency of lengthy continuous CRW arrays was higher than that in either rice or maize. The dynamics of CRWs and other retrotransposons at centromeric and pericentromeric regions during diploid speciation and polyploidization of wheat and its related species are discussed.
authors.affiliation: Key Laboratory of Crop Germplasm & Biotechnology, MOA, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, The National Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, People's Republic of China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Yue
authors.forename: Dayong
authors.initials: D
authors.lastname: Li
authors.forename: Richard R-C
authors.initials: RR
authors.lastname: Wang
authors.forename: Xiuying
authors.initials: X
authors.lastname: Kong
authors.forename: Kun
authors.initials: K
authors.lastname: Lu
authors.forename: Guixiang
authors.initials: G
authors.lastname: Wang
authors.forename: Yushen
authors.initials: Y
authors.lastname: Dong
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jin
authors.forename: Xueyong
authors.initials: X
authors.lastname: Zhang
mesh_terms: D002503:Centromere / Q000235:genetics* / Q000502:physiology; D002843:Chromatin / Q000235:genetics / Q000502:physiology; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics* / Q000502:physiology; D017343:Genes, Plant; D012275:Oryza / Q000235:genetics / Q000502:physiology; D018626:Retroelements / Q000235:genetics / Q000502:physiology*; D014908:Triticum / Q000235:genetics* / Q000502:physiology; D003313:Zea mays / Q000235:genetics / Q000502:physiology
chemical_list: D002843:Chromatin; D018626:Retroelements