title: Composition and structure of the centromeric region of rice chromosome 8.
abstract: Understanding the organization of eukaryotic centromeres has both fundamental and applied importance because of their roles in chromosome segregation, karyotypic stability, and artificial chromosome-based cloning and expression vectors. Using clone-by-clone sequencing methodology, we obtained the complete genomic sequence of the centromeric region of rice (Oryza sativa) chromosome 8. Analysis of 1.97 Mb of contiguous nucleotide sequence revealed three large clusters of CentO satellite repeats (68.5 kb of 155-bp repeats) and >220 transposable element (TE)-related sequences; together, these account for approximately 60% of this centromeric region. The 155-bp repeats were tandemly arrayed head to tail within the clusters, which had different orientations and were interrupted by TE-related sequences. The individual 155-bp CentO satellite repeats showed frequent transitions and transversions at eight nucleotide positions. The 40 TE elements with highly conserved sequences were mostly gypsy-type retrotransposons. Furthermore, 48 genes, showing high BLAST homology to known proteins or to rice full-length cDNAs, were predicted within the region; some were close to the CentO clusters. We then performed a genome-wide survey of the sequences and organization of CentO and RIRE7 families. Our study provides the complete sequence of a centromeric region from either plants or animals and likely will provide insight into the evolutionary and functional analysis of plant centromeres.
authors.affiliation: Rice Genome Research Program, National Institute of Agrobiological Sciences/Institute of the Society for Techno-Inovation of Agriculture, Forestry, and Fisheries, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Wu
authors.forename: Harumi
authors.initials: H
authors.lastname: Yamagata
authors.forename: Mika
authors.initials: M
authors.lastname: Hayashi-Tsugane
authors.forename: Saori
authors.initials: S
authors.lastname: Hijishita
authors.forename: Masaki
authors.initials: M
authors.lastname: Fujisawa
authors.forename: Michie
authors.initials: M
authors.lastname: Shibata
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Ito
authors.forename: Mari
authors.initials: M
authors.lastname: Nakamura
authors.forename: Miyuki
authors.initials: M
authors.lastname: Sakaguchi
authors.forename: Rie
authors.initials: R
authors.lastname: Yoshihara
authors.forename: Harumi
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Kazue
authors.initials: K
authors.lastname: Ito
authors.forename: Wataru
authors.initials: W
authors.lastname: Karasawa
authors.forename: Mayu
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Shoko
authors.initials: S
authors.lastname: Saji
authors.forename: Satoshi
authors.initials: S
authors.lastname: Katagiri
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kanamori
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Namiki
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Katayose
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Takuji
authors.initials: T
authors.lastname: Sasaki
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D002503:Centromere / Q000235:genetics; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D027042:Chromosomes, Artificial, P1 Bacteriophage / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics*; D017124:Conserved Sequence; D004251:DNA Transposable Elements / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D004276:DNA, Satellite / Q000235:genetics; D018745:Genome, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics*; D020161:Physical Chromosome Mapping; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004251:DNA Transposable Elements; D018744:DNA, Plant; D004276:DNA, Satellite