title: Divergence in centromere structure distinguishes related genomes in Coix lacryma-jobi and its wild relative.
abstract: Knowledge about the composition and structure of centromeres is critical for understanding how centromeres perform their functional roles. Here, we report the sequences of one centromere-associated bacterial artificial chromosome clone from a Coix lacryma-jobi library. Two Ty3/gypsy-class retrotransposons, centromeric retrotransposon of C. lacryma-jobi (CRC) and peri-centromeric retrotransposon of C. lacryma-jobi, and a (peri)centromere-specific tandem repeat with a unit length of 153 bp were identified. The CRC is highly homologous to centromere-specific retrotransposons reported in grass species. An 80-bp DNA region in the 153-bp satellite repeat was found to be conserved to centromeric satellite repeats from maize, rice, and pearl millet. Fluorescence in situ hybridization showed that the three repetitive sequences were located in (peri-)centromeric regions of both C. lacryma-jobi and Coix aquatica. However, the 153-bp satellite repeat was only detected on 20 out of the 30 chromosomes in C. aquatica. Immunostaining with an antibody against rice CENH3 indicates that the 153-bp satellite repeat and CRC might be both the major components for functional centromeres, but not all the 153-bp satellite repeats or CRC sequences are associated with CENH3. The evolution of centromeric repeats of C. lacryma-jobi during the polyploidization was discussed.
authors.affiliation: National Maize Improvement Center of China, Key Laboratory of Crop Genetic Improvement and Genome of Ministry of Agriculture, Beijing Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Han
authors.forename: Guixiang
authors.initials: G
authors.lastname: Wang
authors.forename: Zhao
authors.initials: Z
authors.lastname: Liu
authors.forename: Jinhua
authors.initials: J
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Yue
authors.forename: Rentao
authors.initials: R
authors.lastname: Song
authors.forename: Xueyong
authors.initials: X
authors.lastname: Zhang
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jin
mesh_terms: D001483:Base Sequence; D002503:Centromere / Q000235:genetics*; D031742:Coix / Q000235:genetics*; D019143:Evolution, Molecular; D018745:Genome, Plant; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D010944:Plants / Q000235:genetics*; D018626:Retroelements; D016415:Sequence Alignment
chemical_list: D018626:Retroelements