Saccharomyces cerevisiae
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ABSTRACT:
PROVIDER: PRJNA95733 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The segregation of maternal centromeres away from the paternal ones during the first division of meiosis depends on the attachment of sister kinetochores to microtubules emanating from the same spindle pole. In budding yeast monopolar attachment requires the recruitment to kinetochores of a protein complex called monopolin. The biochemical function of monopolin was unknown. Here, we have identified the casein kinase I Hrr25 as a hitherto unknown subunit of monopolin. Hrr25 differs from other monopolin components by its enzymatic activity and strong evolutionary conservation. We demonstrate that Hrr25’s kinase activity and its interaction with monopolin are both required for monopolar attachment. Accordingly, Hrr25 is associated with centromeres in meiosis I. Our results revealed a surprising new role for casein kinases and provide a hypothesis for the mechanism of monopolar attachment during meiosis I in sexually reproducing organisms: casein kinase I-dependent phosphorylation of kinetochore proteins. Keywords: ChIP-chip, Meiosis, Cell cycle, Saccharomyces cerevisiae, Chromosome VI tiling array, Hrr25, Mam1
2006-09-23 | GSE4792 | GEO
Project description:Protein phosphatase 2A protects centromeric sister chromatid cohesion during meiosis I
| PRJNA95731 | ENA
Project description:FACT mediates cohesin function on chromatin Cohesin is a key regulator of genome architecture with roles in sister chromatid cohesion and the organisation of higher-order structures during interphase and mitosis. The recruitment and mobility of cohesin complexes on DNA are restricted by nucleosomes. Here we show that cohesin role in chromosome organization requires the histone chaperone FACT. Depletion of FACT in metaphase cells affects cohesin stability on chromatin reducing its accumulation at pericentric regions and binding on chromosome arms. Using Hi-C, we show that cohesin-dependent TAD (Topological Associated Domains)-like structures in G1 and metaphase chromosomes are disrupted in the absence of FACT. Surprisingly, sister chromatid cohesion is intact in FACT-depleted cells, although chromosome segregation failure is observed. Our results uncover a role for FACT in genome organisation by facilitating cohesin dependent compartmentalization of chromosomes into loop domains.
2019-10-03 | PXD014896 | Pride
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:During meiosis, a single round of DNA replication is followed by two consecutive rounds of nuclear divisions called meiosis I and meiosis II. In meiosis I, homologous chromosomes segregate, while sister chromatids remain together. Determining how this unusual chromosome segregation behavior is established is central to understanding germ cell development. Here we show that preventing microtubule-kinetochore interactions during premeiotic S phase and prophase I is essential for establishing the meiosis I chromosome segregation pattern. Premature interactions of kinetochores with microtubules transform meiosis I into a mitosis-like division by disrupting two key meiosis I events: coorientation of sister kinetochores and protection of centromeric cohesin removal from chromosomes. Furthermore we find that restricting outer kinetochore assembly contributes to preventing premature engagement of microtubules with kinetochores. We propose that inhibition of microtubule-kinetochore interactions during premeiotic S phase and prophase I is central to establishing the unique meiosis I chromosome segregation pattern.
2012-10-05 | GSE41339 | GEO
Project description:The segregation of maternal centromeres away from the paternal ones during the first division of meiosis depends on the attachment of sister kinetochores to microtubules emanating from the same spindle pole. In budding yeast monopolar attachment requires the recruitment to kinetochores of a protein complex called monopolin. The biochemical function of monopolin was unknown. Here, we have identified the casein kinase I Hrr25 as a hitherto unknown subunit of monopolin. Hrr25 differs from other monopolin components by its enzymatic activity and strong evolutionary conservation. We demonstrate that Hrr25âs kinase activity and its interaction with monopolin are both required for monopolar attachment. Accordingly, Hrr25 is associated with centromeres in meiosis I. Our results revealed a surprising new role for casein kinases and provide a hypothesis for the mechanism of monopolar attachment during meiosis I in sexually reproducing organisms: casein kinase I-dependent phosphorylation of kinetochore proteins. Keywords: ChIP-chip, Meiosis, Cell cycle, Saccharomyces cerevisiae, Chromosome VI tiling array, Hrr25, Mam1 ⢠Experimental factors Distribution of the Hrr25 and Mam1 at Meiosis I. Distribution of Hrr25 in Mam1 deletion mutant (S.cerevisiae). All experiments were performed in cells with the same genetic background (Saccharomyces cerevisiae SK1). ⢠Experimental design ChIP analysis: In all cases, hybridization data for ChIP fraction was compared with that of SUP (supernatant) fraction. Cerevisiae chromosome VI array was used. ⢠Quality control steps taken Confirmation using different subunits of the same complex. Confirmation of protein distribution using deletion mutant strain. Checking of the ChIP fraction by Western blotting. Mock hybridisation of samples immunoprecipitated from cells containing no tag recognized by antibody used. Swapping SUP fraction. Q-PCR. Samples used, extract preparation and labelling: ⢠The origin of each biological sample Saccharomyces cerevisiae (SK1). ⢠Manipulation of biological samples and protocols used Chromatin immunoprecipitation (ChIP) and hybridization to Affimetrix high-density oligonucleotide arrays of S. cerevisiae chromosome VI were performed essentially as previously described (Katou et al., 2003, nature) (Lengronne et al., 2004, nature). ⢠Technical protocols for preparing the hybridization extract The chromatin-immunprecipates were eluted and incubated over night at 65ºC to reverse the cross-link. Immunoprecipitated genomic DNA was incubated with proteinase K, extracted 2 times with phenol/chloroform/isoamylalcohol, precipitated, resuspended in TE and incubated with RnaseA. The DNA was then purified using the Qiagen PCR purification kit, and concentrated by ethanol precipitation. The DNA was amplified by PCR after random priming. 10 ug of amplified DNA was digested with Dnase I to a mean size of 100 bp. After Dnase I inactivation at 95ºC. DNA fragments were end-labeled by addition of 25 U of Terminal Transferase and 1 nmol Biotin-N6ddATP (NEN) for 1 hour at 37ºC as previously described by Winzeler et al. (Science. 281, 1194-1197, 1998). The entire sample was used for hybridization. ⢠Hybridization procedures and parameters: Hybridization, blocking and washing were carried out as previously described (http://everythingchromosomevi.gsc.riken.go.jp). Each sample was hybridized to the array in 150 ul containing 6xSSPE; 0.005% TritonX-100; 15 ug fragmented denatured salmon sperm DNA (Gibco-BRL); 1 nmole 3âbiotin labelled control oligonucleotide (oligo B2, Affymetrix). Samples were denatured at 100ºC for 10 minutes, and then put on ice before being hybridized for 16 hours at 42ºC in a hybridization oven (GeneChip Hybridization Oven 640, Affymetrix). Washing and scanning protocol provided by Affymetrix was performed automatically on a fluidics station (GeneChip fluidics station 450, Affymetrix). ⢠Measurement data and specifications: Arrays were scanned using the Genechip Scanner3000 7G following the library array description. All the raw data files can be downloaded from GEO database. The primary analysis of tiling chip data was performed following exactly the statistical algorithm used for Affymetrix GeneChip Operating Software (GCOS). The detailed information for the algorithm used can be downloaded from the Affymetrix web site at http://www.affymetrix.com/support/technical/technotes/statistical_reference_guide.pdf. The analysis is available on request. For the ChrVI array, one unit for analysis (locus) was set to 300bp. Fold change value, change p-value, and detection p-value for each locus were obtained by primary analysis. For the discrimination of positive and negative signals for the binding, we used three criteria as follows. First, the reliability of the signal strength was judged by detection p-value of each locus (p-valueâ¤0.025). Secondly, reliability of binding ratio was judged by change p-value (p-valueâ¤0.025). Thirdly, clusters consisting of at least 900bp contiguous loci that satisfied the above two criteria were selected, because it is known that a single site of protein-DNA interaction resulted in immuno-precipitation of DNA fragments that hybridized not only to the locus of the actual binding site but also to its neighbors. ⢠Array Design: General array design: in situ synthesized arrays by Affymetrix Availability of arrays: commercially available from Affymetrix Location and ID of each spot on arrays: available from Affymetrix on request Probe type: oligonucleotide The arrays used in this study can be purchased from Affymetrix: Chromosome VI S.cerevisiae: rikDACFC6, P/N# 510636
2010-06-10 | E-GEOD-4792 | biostudies-arrayexpress
Project description:Meiosis produces gametes through a specialised, two-step cell division, which is highly error-prone in humans. Reductional meiosis I, where maternal and paternal chromosomes (homologs) segregate, is followed by equational meiosis II, where sister chromatids separate. Uniquely during meiosis I, sister kinetochores are monooriented and pericentromeric cohesin is protected. Here, we demonstrate that these key adaptations for reductional chromosome segregation are achieved through separable control of multiple kinases by the meiosis I-specific budding yeast Spo13 protein. Recruitment of Polo kinase to kinetochores directs monoorientation, while, independently, cohesin protection is achieved by controlling the effects of cohesin kinases. Therefore, reductional chromosome segregation, the defining feature of meiosis, is established by multifaceted kinase control by a master regulator. The recent identification of Spo13 orthologs, fission yeast Moa1 and mouse MEIKIN, suggests that kinase coordination by a master meiosis I regulator may be a general feature in the establishment of reductional chromosome segregation.
2019-11-13 | PXD012627 | Pride
Project description:A novel response to microtubule perturbation in meiosis
| PRJNA90655 | ENA
Project description:Transcriptomic regulation during meiosis
| PRJNA108783 | ENA
Project description:Sister chromatid cohesion establishment by acetylation
| PRJNA106243 | ENA