Schizosaccharomyces pombe
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ABSTRACT:
PROVIDER: PRJNA96477 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:A high-resolution map of inner kinetochore proteins in fission yeast regional centromeres
| PRJNA270660 | ENA
Project description:A key element for defining the centromere identity is the incorporation of a specific histone H3, CENP-A, known as Cnp1p in S. pombe. Previous studies have suggested that functional S. pombe centromeres lack nucleosome arrays and may involve chromatin remodeling as a key step of kinetochore assembly. We used tiling microarrays to show that nucleosomes are in fact positioned in regular intervals in the core of centromere 2, providing the first high resolution map of regional centromere chromatin. Nucleosome locations are not disrupted by mutations in kinetochore proteins cnp1, mis18, mis12, nuf2, mal2, overexpression of Cnp1p, or deletion of ams2. Bioinformatic analysis of the centromere sequence indicates certain enriched motifs in linker regions between nucleosomes and reveals a sequence-bias in nucleosome positioning. We conclude that centromeric nucleosome positions are stable and may be derived from the underlying DNA sequence. In addition, sequence analysis of nucleosome-free regions identifies novel binding sites for the GATA-like protein Ams2p, which participates in CENP-A incorporation. Keywords: Nucleosome Mapping Study
2008-05-30 | GSE10742 | GEO
Project description:A DNA polymerase a accessory protein, Mcl1, is required for propagation of centromere structures in fission yeast
| PRJNA106985 | ENA
Project description:We report the high-throughput profiling of histone modification (H3K9me2) in fission yeast Schizosaccharomyces pombe. By obtaining 1-10 ng immunoprecipitated DNA, we generated genome-wide H3K9me2 maps of fission yeast mutants with either deletions of non-essential kinetochore genes or conditional inactivation (temperature sensitive, ts) mutations in essential ones. We find that the impairment of the kinetochore componnets cause various levels (from no to prominent) of heterochroamatin spreading into centromeric core regions. Hence, we conclude that the integrity of the inner kinetochore is required to maintain normal centromeric chromatin organization as well as distinct centromere identity.
2019-09-28 | GSE117948 | GEO
Project description:A key element for defining the centromere identity is the incorporation of a specific histone H3, CENP-A, known as Cnp1p in S. pombe. Previous studies have suggested that functional S. pombe centromeres lack nucleosome arrays and may involve chromatin remodeling as a key step of kinetochore assembly. We used tiling microarrays to show that nucleosomes are in fact positioned in regular intervals in the core of centromere 2, providing the first high resolution map of regional centromere chromatin. Nucleosome locations are not disrupted by mutations in kinetochore proteins cnp1, mis18, mis12, nuf2, mal2, overexpression of Cnp1p, or deletion of ams2. Bioinformatic analysis of the centromere sequence indicates certain enriched motifs in linker regions between nucleosomes and reveals a sequence-bias in nucleosome positioning. We conclude that centromeric nucleosome positions are stable and may be derived from the underlying DNA sequence. In addition, sequence analysis of nucleosome-free regions identifies novel binding sites for the GATA-like protein Ams2p, which participates in CENP-A incorporation. Keywords: Nucleosome Mapping Study Entire cnt regions and histone-related genes were tiled at 1-5 bp spacing using 60-mer probes.
2008-05-30 | E-GEOD-10742 | biostudies-arrayexpress
Project description:The metazoan nuclear periphery is involved in transcriptional regulation and chromatin organisation. To test whether this is also the case in the fission yeast Schizosaccharomyces pombe, we performed DamID experiments with two inner nuclear membrane (INM) proteins, Ima1 and Man1. The resulting map showed that about a third of the genome is associated with the nuclear periphery. We find that both INM proteins preferentially associate with lowly expressed genes, and are depleted from highly expressed genes. Further, intergenic regions of divergent gene pairs are more frequently associated with the periphery than convergent pairs, indicating that transcription points away from the periphery rather than toward it
2012-01-18 | GSE30476 | GEO
Project description:Heterochromatin integrity affects chromosome reorganization after centromere dysfunction
| PRJNA108495 | ENA
Project description:Chromosome segregation depends on proper attachment of sister kinetochores to microtubules. Merotelic kinetochore orientation is an error which occurs when a single kinetochore is attached to microtubules emanating form opposite poles. Mechanisms preventing or correcting the merotelic attachment must operate to avoid chromosome missegregation. Pcs1 has been implicated in preventing merotelic attachment in mitosis and meiosis II. We describe here the identification of Mde4 protein which forms a complex with the Pcs1. Both Mde4 and Pcs1 localize to the central core of the centromere. Similarly to the pcs1 mutant, in the absence of mde4 lagging chromosomes are frequently observed during mitosis and meiosis II . We provide the first evidence that the lagging chromosomes in pcs1 and mde4 mutants are due to merotelic kinetochore orientation. Keywords: ChIP-chip analysis
2007-06-18 | GSE5257 | GEO
Project description:The centromere is a vital locus on each chromosome which seeds the kinetochore, allowing for a physical connection between the chromosome and the mitotic spindle. At the heart of the centromere is the centromere-specific histone H3 variant CENP-A/CENH3. Throughout the cell cycle the constitutive centromere associated network is bound to CENP-A chromatin, but how this protein network modifies CENP-A nucleosome dynamics in vivo is unknown. Here, using a combination of biophysical and biochemical analyses we provide evidence for the existence of two populations of structurally distinct CENP-A nucleosomes that co-exist at human centromeres. These two populations display unique sedimentation patterns in a glycerol gradient, and CENP-A nucleosomes that are physically associated with the inner kinetochore appear stabilized in an octameric conformation, with restricted access to the nucleosomal DNA by DNase I. In contrast, the bulk population of CENP-A nucleosomes have diminished heights and weakened DNA interactions. These data suggest that, in vivo, a reserve pool of immature CENP-A nucleosomes exist which wrap DNA loosely, whereas an active inner kinetochore complex associates with stabilized CENP-A nucleosomes. Our data have implications for a function for CENP-A that may be independent of its role in mitotis.
2020-04-02 | GSE129351 | GEO
Project description:Kinetochores are macromolecular protein complexes that ensure accurate chromosome segregation by linking chromosomes to spindle microtubules and integrating safeguard mechanisms. In yeast, the inner kinetochore, also known as Constitutive Centromere Associated Network (CCAN), is specifically established at point centromeres and has been implicated in contributing to Aurora-BIpl1 function. In an attempt to gain a more detailed picture of the budding yeast kinetochore architecture, crosslink-guided in vitro reconstitution revealed novel direct interactions of the inner kinetochore assembled on Cse4CENP-A nucleosomes. The Ame1/Okp1CENP-U/Q heterodimer selectively bound Cse4CENP-A nucleosomes through the Cse4 N-terminus, providing an explanation for the essential role of the COMA complex in budding yeast. Moreover, the Sli15/Ipl1 core chromosomal passenger complex was found to directly interact with COMA in vitro, suggesting a hitherto unknown role of the COMA complex in establishing biorientation. In line with this finding, in vivo artificial tethering of Sli15 to inner kinetochore proteins rescued synthetically lethal subunit deletion phenotypes in a Sli15 centromere targeting deficient mutant. This study reveals characteristics of the inner kinetochore architecture assembled at point centromeres and its implications on chromosomal passenger complex function.
2019-04-12 | PXD011236 | Pride