Oryza sativa
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PROVIDER: PRJNA218812 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Plant and animal centromeres comprise megabases of highly repeated satellite sequences, yet centromere function can be specified epigenetically on single-copy DNA by the presence of nucleosomes containing a centromere-specific variant of histone H3 (cenH3). We determined the positions of cenH3 nucleosomes in rice (Oryza sativa), which has centromeres composed of both the 155-bp CentO repeat and single-copy non-CentO sequences. We find that cenH3 nucleosomes protect 90-100 bp of DNA from micrococcal nuclease digestion, sufficient for only a single wrap of DNA around the cenH3 nucleosome core. cenH3 nucleosomes are translationally phased with 155-bp periodicity on CentO repeats, but not on non-CentO sequences. CentO repeats have a ~10-bp periodicity in WW dinucleotides and in micrococcal nuclease cleavage, providing evidence for rotational phasing of cenH3 nucleosomes on CentO, and suggesting that satellites evolve for translational and rotational stabilization of centromeric nucleosomes. Examination of measured size of rice centromere nucleosome
2013-11-06 | E-GEOD-50755 | biostudies-arrayexpress
Project description:Plant and animal centromeres comprise megabases of highly repeated satellite sequences, yet centromere function can be specified epigenetically on single-copy DNA by the presence of nucleosomes containing a centromere-specific variant of histone H3 (cenH3). We determined the positions of cenH3 nucleosomes in rice (Oryza sativa), which has centromeres composed of both the 155-bp CentO repeat and single-copy non-CentO sequences. We find that cenH3 nucleosomes protect 90-100 bp of DNA from micrococcal nuclease digestion, sufficient for only a single wrap of DNA around the cenH3 nucleosome core. cenH3 nucleosomes are translationally phased with 155-bp periodicity on CentO repeats, but not on non-CentO sequences. CentO repeats have a ~10-bp periodicity in WW dinucleotides and in micrococcal nuclease cleavage, providing evidence for rotational phasing of cenH3 nucleosomes on CentO, and suggesting that satellites evolve for translational and rotational stabilization of centromeric nucleosomes.
2013-11-06 | GSE50755 | GEO
Project description:Specification and propagation of the centromeres of eukaryotic chromosomes is determined by epigenetic mechanisms. Unfortunately, the epigenetic characteristics of centromeric DNA and chromatin are difficult to define because the centromeres are composed of highly repetitive DNA sequences in most eukaryotic species. Several rice centromeres have been fully sequenced, making rice an excellent model for centromere research. We conducted genome-wide mapping of cytosine methylation using methylcytosine immunoprecipitation combined with Illumina sequencing. The DNA sequences in the core domains of rice Cen4, Cen5, and Cen8 showed elevated methylation levels compared to the sequences in the pericentromeric regions. In addition, elevated methylation levels were associated with the DNA sequences in the CENH3-binding subdomains compared to the sequences in the flanking H3 subdomains. In contrast, the centromeric domain of Cen11, which is composed exclusively of centromeric satellite DNA, is hypomethylated compared to the pericentromeric domains. Thus, the DNA sequences associated with functional centromeres can be either hypomethylated or hypermethylated. The methylation patterns of centromeric DNA appear to be correlated with the composition of the associated DNA sequences. We propose that both hypomethylation and hypermethylation of CENH3-associated DNA sequences can serve as epigenetic marks to distinguish where CENH3 deposition will occur within the surrounding H3 chromatin. mCIP-seq of one sample of rice seedling
2010-04-22 | E-GEOD-21414 | biostudies-arrayexpress
Project description:We use high-resolution chemical cleavage mapping and both native and cross-linked chromatin immunoprecipitation with paired-end sequencing to elucidate the profile of nuceleosomes containing the centromere-specific variant of H3 (cenH3), known as CENP-A or Cnp1 in fission yeast. We find that in the central domain of fission yeast centromeres H3 nucleosomes are nearly absent and CENP-A nucleosomes are more widely spaced that nucleosomes elsewere. CENP-A (Cnp1), CENP-C (Cnp3), CENP-T (Cnp20) and CENP-I (Mis6) are highly enriched at every position in the central domain except at tRNA genes, with weak enrichment in the flanking heterochromatin where these proteins show no evidence of the positioning that has been seen in point centromeres and in the satellite-rich centromeres of plants and animals. Our findings suggest that classical regional centromeres are distinguished from other centromere classes by the absence of cenH3 nucleosome positioning.
2015-08-17 | GSE64294 | GEO
Project description:The centromere is the chromosomal site for assembly of the kinetochore where spindle fibers attach during cell division. In most muticellular eukaryotes, centromeres are composed of long tracks of satellite repeats that are recalcitrant to sequencing and fine scale genetic mapping. Here we report the genomic and genetic characterization of the complete centromere of rice chromosome 3. Using a DNA fiber-fluorescence in situ hybridization approach, we demonstrated that the centromere of chromosome 3 (Cen3) contains ~414 kb of the centromeric satellite repeat CentO. Cen3 includes a ~1,851-kb domain associated with CENH3, the centromere-specific histone H3 variant. This CENH3-associated chromatin domain is embedded within a 3,083-kb region that lacks genetic recombination. We detected several active genes within the CENH3-binding domain based on a comprehensive annotation and a survey for matches with mRNA signatures. However, the gene density in the CENH3-binding domain is significantly lower than in the pericentromeric domains. In contrast, the CENH3-binding domain contains a higher percentage of repetitive DNA sequences than the pericentromeric regions. These results suggest that Cen3 is in the process of evolving from a genic region toward an accumulation of satellite repeats and transposable elements that is more characteristic of centromeres in most complex eukaryotic species. Keywords: MPSS, mRNA, transcriptome, rice, centromere, Cen3, chromosome 3
2006-05-26 | GSE4920 | GEO
Project description:The centromere is the chromosomal site for assembly of the kinetochore where spindle fibers attach during cell division. In most muticellular eukaryotes, centromeres are composed of long tracks of satellite repeats that are recalcitrant to sequencing and fine scale genetic mapping. Here we report the genomic and genetic characterization of the complete centromere of rice chromosome 3. Using a DNA fiber-fluorescence in situ hybridization approach, we demonstrated that the centromere of chromosome 3 (Cen3) contains ~414 kb of the centromeric satellite repeat CentO. Cen3 includes a ~1,851-kb domain associated with CENH3, the centromere-specific histone H3 variant. This CENH3-associated chromatin domain is embedded within a 3,083-kb region that lacks genetic recombination. We detected several active genes within the CENH3-binding domain based on a comprehensive annotation and a survey for matches with mRNA signatures. However, the gene density in the CENH3-binding domain is significantly lower than in the pericentromeric domains. In contrast, the CENH3-binding domain contains a higher percentage of repetitive DNA sequences than the pericentromeric regions. These results suggest that Cen3 is in the process of evolving from a genic region toward an accumulation of satellite repeats and transposable elements that is more characteristic of centromeres in most complex eukaryotic species. Keywords: MPSS, small RNA, rice, centromere, Cen3, chromosome 3
2006-05-26 | GSE4912 | GEO
Project description:The centromere is the chromosomal site for assembly of the kinetochore where spindle fibers attach during cell division. In most muticellular eukaryotes, centromeres are composed of long tracks of satellite repeats that are recalcitrant to sequencing and fine scale genetic mapping. Here we report the genomic and genetic characterization of the complete centromere of rice chromosome 3. Using a DNA fiber-fluorescence in situ hybridization approach, we demonstrated that the centromere of chromosome 3 (Cen3) contains ~414 kb of the centromeric satellite repeat CentO. Cen3 includes a ~1,851-kb domain associated with CENH3, the centromere-specific histone H3 variant. This CENH3-associated chromatin domain is embedded within a 3,083-kb region that lacks genetic recombination. We detected several active genes within the CENH3-binding domain based on a comprehensive annotation and a survey for matches with mRNA signatures. However, the gene density in the CENH3-binding domain is significantly lower than in the pericentromeric domains. In contrast, the CENH3-binding domain contains a higher percentage of repetitive DNA sequences than the pericentromeric regions. These results suggest that Cen3 is in the process of evolving from a genic region toward an accumulation of satellite repeats and transposable elements that is more characteristic of centromeres in most complex eukaryotic species. MPSS was performed to sequence small RNAs that derived from 16 untreated and 6 abiotic-treated diverse tissue libraries. The method for the MPSS sequencing of mRNAs is described in Brenner et al. (Nat Biotechnol. 2000 18:630).
2006-05-26 | E-GEOD-4920 | biostudies-arrayexpress
Project description:The centromere is the chromosomal site for assembly of the kinetochore where spindle fibers attach during cell division. In most muticellular eukaryotes, centromeres are composed of long tracks of satellite repeats that are recalcitrant to sequencing and fine scale genetic mapping. Here we report the genomic and genetic characterization of the complete centromere of rice chromosome 3. Using a DNA fiber-fluorescence in situ hybridization approach, we demonstrated that the centromere of chromosome 3 (Cen3) contains ~414 kb of the centromeric satellite repeat CentO. Cen3 includes a ~1,851-kb domain associated with CENH3, the centromere-specific histone H3 variant. This CENH3-associated chromatin domain is embedded within a 3,083-kb region that lacks genetic recombination. We detected several active genes within the CENH3-binding domain based on a comprehensive annotation and a survey for matches with mRNA signatures. However, the gene density in the CENH3-binding domain is significantly lower than in the pericentromeric domains. In contrast, the CENH3-binding domain contains a higher percentage of repetitive DNA sequences than the pericentromeric regions. These results suggest that Cen3 is in the process of evolving from a genic region toward an accumulation of satellite repeats and transposable elements that is more characteristic of centromeres in most complex eukaryotic species. MPSS was performed to sequence small RNAs that derived from inflorescence and seedling. The method for the MPSS sequencing of small RNAs are described in the paper associated with this dataset (Lu et al., 2005).
2006-05-26 | E-GEOD-4912 | biostudies-arrayexpress
Project description:Specification and propagation of the centromeres of eukaryotic chromosomes is determined by epigenetic mechanisms. Unfortunately, the epigenetic characteristics of centromeric DNA and chromatin are difficult to define because the centromeres are composed of highly repetitive DNA sequences in most eukaryotic species. Several rice centromeres have been fully sequenced, making rice an excellent model for centromere research. We conducted genome-wide mapping of cytosine methylation using methylcytosine immunoprecipitation combined with Illumina sequencing. The DNA sequences in the core domains of rice Cen4, Cen5, and Cen8 showed elevated methylation levels compared to the sequences in the pericentromeric regions. In addition, elevated methylation levels were associated with the DNA sequences in the CENH3-binding subdomains compared to the sequences in the flanking H3 subdomains. In contrast, the centromeric domain of Cen11, which is composed exclusively of centromeric satellite DNA, is hypomethylated compared to the pericentromeric domains. Thus, the DNA sequences associated with functional centromeres can be either hypomethylated or hypermethylated. The methylation patterns of centromeric DNA appear to be correlated with the composition of the associated DNA sequences. We propose that both hypomethylation and hypermethylation of CENH3-associated DNA sequences can serve as epigenetic marks to distinguish where CENH3 deposition will occur within the surrounding H3 chromatin.
2010-04-22 | GSE21414 | GEO
Project description:The centromere is defined by the presence of a centromere-specific histone H3 variant, CENH3. Establishment and maintenance of the centromeric chromatin (CEN chromatin) is determined by poorly understood epigenetic mechanisms. Interestingly, CEN chromatin in several eukaryotes showed euchromatic characteristics although being embedded within pericentromeric heterochromatin. Specifically, H3K4me2 appeared to be a unique histone modification mark associated with animal centromeres. We developed a genomic tiling array for four fully sequenced rice centromeres. A ChIP-chip approach was used to study the patterns of several euchromatic histone modification marks, including H3K4me2, H3K4me3, H3K36me3, and H3K4K9a, associated with rice centromeres. We demonstrate that the CENH3 subdomains within the four centromeres are depleted with the four histone H3 marks. The vast majority of the four histone marks were associated with the genes located in the H3 subdomains within the centromeric cores. Genes in the centromeres showed similar histone modification patterns as those located outside of the centromeres. Thus, the euchromatic characteristics of rice CEN chromatin are trademarks of the transcribed sequences embedded in the H3 subdomains of the centromeres. We propose that the constitutively expressed genes located in rice centromeres may provide a barrier for loading of CENH3 into the H3 subdomains. The separation of CENH3 into the H3 subdomains is favorable for the three dimensional structure and its associated function of rice centromeres.
2011-11-09 | GSE29597 | GEO