Epigenetic characteristics and gene-expression analysis of Derivative 3-3 de novo centromere in maize
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ABSTRACT:
ORGANISM(S): Zea mays
PROVIDER: GSE76533 | GEO | 2016/08/05
SECONDARY ACCESSION(S): PRJNA307655
REPOSITORIES: GEO
Similar Datasets
Project description:De novo centromeres originate occasionally from non-centromeric regions of chromosomes, providing an excellent model system to study centromeric chromatin. The maize mini-chromosome Derivative 3-3 contains a de novo centromere, which was derived from a euchromatic site on the short arm of chromosome 9 that lacks traditional centromeric repeat sequences. Our previous study found that the CENH3 binding domain of this de novo centromere is only 288 kb with a high-density gene distribution with low-density of transposons. Here we applied next generation sequencing technology to analyze gene transcription, DNA methylation for this region. Our RNA-seq data revealed that active chromatin is not a barrier for de novo centromere formation. Bisulfite-ChIP-seq results indicate a slightly increased DNA methylation level after de novo centromere formation, reaching the level of a native centromere. These results provide insight into the mechanism of de novo centromere formation and subsequent consequences. RNA-seq was carried out using material from seedling and young leaves between control and Derivative 3-3. Bisulfite-ChIP-seq was carried out with anti-CENH3 antibodies using material from young leaves in Derivative 3-3.
2016-08-05 | E-GEOD-76533 | biostudies-arrayexpress
Project description:De novo centromeres originate occasionally from non-centromeric regions of chromosomes, providing an excellent model system to study centromeric chromatin. The maize mini-chromosome Dp3a contains a de novo centromere, which was derived from a euchromatic site on the long arm of chromosome 3 that lacks traditional centromeric repeat sequences. Our previous study found that the CENH3 binding domain of this de novo centromere is only 350 kb with a high-density gene distribution with low-density of transposons. Here we analyzed the kinetochore complex assembled on the de novo centromere, which revealed that it resembles the native centromeres. Meiotic analyses showed that the Dp3a mini-chromosome formed bi-orientation during meiosis I and could stably transmit through meiosis. We applied next generation sequencing technology to analyze gene transcription, DNA methylation and histone modifications for this region. Our RNA-seq data revealed that active chromatin is not a barrier for de novo centromere formation. The gene expression level within the Dp3a breakpoints of native chromosome 3 indicated a gene dosage effect due to the additional copy of Dp3a mini-chromosome region in chromosome 3. Bisulfite-ChIP-seq results indicate a slightly increased DNA methylation level after de novo centromere formation, reaching the level of a native centromere. No strand-specific bias of DNA methylation was found at maize native and Dp3a de novo centromeres. H2A-T133 phosphorylation occurs in the CENH3 nucleosome. These results provide insight into the mechanism of de novo centromere formation and subsequent consequences.
2016-12-01 | GSE64641 | GEO
Project description:The ability of centromeres to alternate between active and inactive states indicates significant epigenetic elements controlling centromere assembly and centromere function. In maize (Zea mays), misdivision of the B chromosome centromere on a translocation with the short arm of chromosome 9 (TB-9Sb) can produce many variants with varying centromere sizes and centromeric DNA sequences. In derivatives of TB-9Sb, we found a de novo centromere on chromosome telo-3-3, which has no canonical centromeric repeat sequences. This centromere is derived from a 288-kb region on the short arm of chromosome 9, and is 19 megabases (Mb) removed from the translocation breakpoint of chromosome 9 in TB-9Sb. This centromere is much smaller than normal ones but can be maintained through meiosis. The functional B centromere in progenitor telo2-2 is deleted from telo3-3 but some B-repeat sequences remain. The de novo centromere of telo3-3 becomes inactive in three further derivatives with new centromeres being formed elsewhere on the chromosomes. One such de novo centromere contains only 200-kb CENH3 binding domain. This 200-kb centromere is located 3 Mb removed from the translocation breakpoint in a new location. The deleted B centromere in telo3-3 is activated in two derivatives. Our results suggest that de novo centromere formation is more common than previously thought and can persist on chromosomal fragments without a canonical centromere providing implications for karyotype evolution. ChIP-seq was carried out with anti-CENH3 antibodies using material from young leaves with control, telo3-3 and its derivate.
2015-03-03 | E-GEOD-59124 | biostudies-arrayexpress
Project description:The ability of centromeres to alternate between active and inactive states indicates significant epigenetic elements controlling centromere assembly and centromere function. In maize (Zea mays), misdivision of the B chromosome centromere on a translocation with the short arm of chromosome 9 (TB-9Sb) can produce many variants with varying centromere sizes and centromeric DNA sequences. In derivatives of TB-9Sb, we found a de novo centromere on chromosome telo-3-3, which has no canonical centromeric repeat sequences. This centromere is derived from a 288-kb region on the short arm of chromosome 9, and is 19 megabases (Mb) removed from the translocation breakpoint of chromosome 9 in TB-9Sb. This centromere is much smaller than normal ones but can be maintained through meiosis. The functional B centromere in progenitor telo2-2 is deleted from telo3-3 but some B-repeat sequences remain. The de novo centromere of telo3-3 becomes inactive in three further derivatives with new centromeres being formed elsewhere on the chromosomes. One such de novo centromere contains only 200-kb CENH3 binding domain. This 200-kb centromere is located 3 Mb removed from the translocation breakpoint in a new location. The deleted B centromere in telo3-3 is activated in two derivatives. Our results suggest that de novo centromere formation is more common than previously thought and can persist on chromosomal fragments without a canonical centromere providing implications for karyotype evolution.
2015-03-03 | GSE59124 | GEO
Project description:Centromeres typically contain repeat sequences, but centromere function does not necessarily depend on these sequences. In aneuploid wheat (Triticum aestivum) and wheat distant hybridization offspring, we found functional centromeres with dramatic changes to centromeric retrotransposon of wheat (CRW) sequences. CRW sequences were greatly reduced in the ditelosomic lines 1BS, 5DS, 5DL, and a wheat-Thinopyrum elongatum addition line. CRWs were completely lost in the ditelosomic line 4DS, but a 994 kb ectopic genomic DNA sequence was involved in de novo centromere formation on the 4DS chromosome. In addition, two ectopic sequences were incorporated in a de novo centromere in a wheat-Th. intermedium addition line. Centromeric sequences were also expanded to the chromosome arm in wide hybridizations. Stable alien chromosomes with two and three regions containing centromeric sequences were found in wheat-Th. elongatum hybrid derivatives, but only one is functional. In wheat-rye (Secale cereale) hybrids, rye centromere specific sequences spread to the chromosome arm and may cause centromere expansion. Thus, distant wheat hybridizations cause frequent and significant changes to the centromere via centromere misdivision, which may affect retention or loss of alien chromosomes in hybrids. ChIP-seq was carried out with anti-CENH3 antibody using material 4DS and control (Chinese Spring, CS as short).
2016-04-02 | E-GEOD-63752 | biostudies-arrayexpress
Project description:Centromeres typically contain repeat sequences, but centromere function does not necessarily depend on these sequences. In aneuploid wheat (Triticum aestivum) and wheat distant hybridization offspring, we found functional centromeres with dramatic changes to centromeric retrotransposon of wheat (CRW) sequences. CRW sequences were greatly reduced in the ditelosomic lines 1BS, 5DS, 5DL, and a wheat-Thinopyrum elongatum addition line. CRWs were completely lost in the ditelosomic line 4DS, but a 994 kb ectopic genomic DNA sequence was involved in de novo centromere formation on the 4DS chromosome. In addition, two ectopic sequences were incorporated in a de novo centromere in a wheat-Th. intermedium addition line. Centromeric sequences were also expanded to the chromosome arm in wide hybridizations. Stable alien chromosomes with two and three regions containing centromeric sequences were found in wheat-Th. elongatum hybrid derivatives, but only one is functional. In wheat-rye (Secale cereale) hybrids, rye centromere specific sequences spread to the chromosome arm and may cause centromere expansion. Thus, distant wheat hybridizations cause frequent and significant changes to the centromere via centromere misdivision, which may affect retention or loss of alien chromosomes in hybrids.
2016-04-02 | GSE63752 | GEO
Project description:A small fragment from maize chromosome 3 was created by irradiation by Stadler and Roman and named Duplication 3a (or Dp3a). This small chromosome does not contain any detectable CentC and CRM sequences, but when molecular features of functional centromeres such as CENH3 and CENP-C were examined, they were present. Immunolocalization analysis of phosphorylation of Ser-10 of histone H3 levels on Dp3a shows a pattern typical of a functional centromere. Meiotic analysis revealed that sister chromatids divided equationally at meiosis I as do all small chromosomes examined to date in maize. To examine the sequences associated with CENH3, chromatin immunoprecipitation (ChIP) was carried out with anti-CENH3 antibodies using material from young seedlings with and without Dp3 chromosome as the tissue source. The ChIPed DNA sample was then labeled for FISH detection and prepared for Illumina sequencing.The ChIP-Seq reads were mapped to the B73 reference genome and a significant peak was detected in the Dp3a sample that span 350 kb of the long arm of chromosome 3, which is the candidate region for association with CENH3. ChIP-bisulfite-seq results indicated that there is a slightly increased DNA methylation level after the centromere formation, approaching the level similar to normal centromere regions. Collectively, the results suggest the formation of a de novo centromere on this fragment that initially must have started at the time of X-irradiation release from the progenitor chromosome. These observations add further evidence for the epigenetic nature of centromere function in maize. ChIP-seq was carried out with anti-CENH3 antibodies using material from young seedlings with and without Dp3a chromosome. For Dp3a, some ChIPed DNA was treated with sodium bisulfite and prepared for Illumina sequencing to test its methylation level.
2013-06-25 | E-GEOD-43138 | 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. 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:A small fragment from maize chromosome 3 was created by irradiation by Stadler and Roman and named Duplication 3a (or Dp3a). This small chromosome does not contain any detectable CentC and CRM sequences, but when molecular features of functional centromeres such as CENH3 and CENP-C were examined, they were present. Immunolocalization analysis of phosphorylation of Ser-10 of histone H3 levels on Dp3a shows a pattern typical of a functional centromere. Meiotic analysis revealed that sister chromatids divided equationally at meiosis I as do all small chromosomes examined to date in maize. To examine the sequences associated with CENH3, chromatin immunoprecipitation (ChIP) was carried out with anti-CENH3 antibodies using material from young seedlings with and without Dp3 chromosome as the tissue source. The ChIPed DNA sample was then labeled for FISH detection and prepared for Illumina sequencing.The ChIP-Seq reads were mapped to the B73 reference genome and a significant peak was detected in the Dp3a sample that span 350 kb of the long arm of chromosome 3, which is the candidate region for association with CENH3. ChIP-bisulfite-seq results indicated that there is a slightly increased DNA methylation level after the centromere formation, approaching the level similar to normal centromere regions. Collectively, the results suggest the formation of a de novo centromere on this fragment that initially must have started at the time of X-irradiation release from the progenitor chromosome. These observations add further evidence for the epigenetic nature of centromere function in maize.
2013-06-25 | GSE43138 | GEO