Saccharomyces cerevisiae
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA284936 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Transcription Dynamically Patterns the Meiotic Chromosome-Axis Interface [ChIP-Seq]
| PRJNA284935 | ENA
Project description:Transcription Dynamically Patterns the Meiotic Chromosome-Axis Interface
| PRJNA287662 | ENA
Project description:During meiotic prophase, concurrent transcription, recombination, and chromosome synapsis place substantial topological strain on chromosomal DNA, but the role of topoisomerases in this context remains poorly defined. Here, we analyzed the roles topoisomerases I and II (Top1 and Top2) during meiotic prophase in Saccharomyces cerevisiae. We show that both topoisomerases accumulate primarily in promoter-containing intergenic regions of actively transcribing genes, including many meiotic double-strand break (DSB) hotspots. Despite the comparable binding patterns, top1 and top2 mutations have different effects on meiotic recombination. TOP1 disruption delays DSB induction and shortens the window of DSB accumulation by an unknown mechanism. By contrast, temperature-sensitive top2-1 mutants exhibit a marked delay in meiotic chromosome remodeling and elevated DSB signals on synapsed chromosomes. The problems in chromosome remodeling were linked to altered Top2 binding patterns rather than a loss of Top2 catalytic activity and stemmed from a defect in recruiting the chromosome remodeler Pch2/TRIP13 to synapsed chromosomes. No chromosomal defects were observed in the absence of TOP1. Our results imply independent roles for topoisomerases I and II in modulating meiotic chromosome structure and recombination.
2020-03-06 | GSE131994 | GEO
Project description:Successful meiotic recombination, and thus fertility, depends on conserved axis proteins that organize chromosomes into arrays of anchored chromatin loops and provide a protected environment for DNA exchange. Here, we show that the stereotypic chromosomal distribution of axis proteins in S. cerevisiae is the additive result of two independent pathways: a cohesin-dependent pathway, which was previously identified and mediates focal enrichment of axis proteins at gene ends, and a parallel cohesin-independent pathway that recruits axis proteins to broad genomic islands with high gene density. These islands exhibit elevated markers of crossover recombination as well as increased nucleosome density, which we show is a direct consequence of the underlying DNA sequence. A predicted PHD domain in the center of the axis factor Hop1 specifically mediates cohesin-independent axis recruitment. Intriguingly, other chromosome organizers, including cohesin, condensin, and topoisomerases, are differentially depleted from the same regions even in non-meiotic cells, indicating that these DNA sequence-defined chromatin islands exert a general influence on the patterning of chromosome structure.
2022-04-08 | GSE156040 | GEO
Project description:Reduced dosage of the chromosome axis factor Red1 selectively disrupts the meiotic recombination checkpoint in Saccharomyces cerevisiae
| PRJNA343422 | ENA
Project description:Spo11-accessory proteins link DNA double-strand break sites to the chromosome axis in early meiotic recombination
| PRJNA140909 | ENA
Project description:The meiotic chromosome axis coordinates chromosome organization and interhomolog recombination in meiotic prophase, and is essential for fertility. In S. cerevisiae, the HORMAD protein Hop1 mediates an enrichment of axis proteins at nucleosome-rich genomic islands through a central chromatin-binding region (CBR). Here, we use cryoelectron microscopy to show that the Hop1 CBR directly recognizes bent nucleosomal DNA through a composite interface in its PHD and winged helix-turn-helix domains. Targeted disruption of the Hop1 CBR-nucleosome interface causes a loss of axis-protein enrichment at nucleosome-rich genomic islands, reduces meiotic DNA double-strand breaks (DSBs), and causes defects in chromosome synapsis. Synthetic effects with the disassemblase Pch2 suggest that nucleosome binding delays a conformational switch in Hop1 from a DSB-promoting, Pch2-inaccessible state to a DSB-inactive, Pch2-accessible state to regulate the extent of meiotic DSB formation . Phylogenetic analyses of meiotic HORMADs reveal an ancient origin of this domain, suggesting that these mechanisms are broadly conserved.
2024-02-28 | GSE225129 | GEO
Project description:Meiotic chromosomes are highly compacted yet remain transcriptionally active. To understand how chromosome folding accommodates transcription, we investigated the assembly of the axial element, the proteinaceous structure that compacts meiotic chromosomes and promotes recombination and fertility. We found that the axial element proteins of budding yeast are flexibly anchored to chromatin by the ring-like cohesin complex and biased towards small chromosomes by a separate modulating mechanism that requires the conserved axial-element component Hop1. The ubiquitous presence of cohesin at sites of convergent transcription provides well-dispersed points for axis attachment and thus compaction. Axis protein enrichment at these sites directly correlates with the propensity for recombination initiation. Importantly, axis anchoring by cohesin is adjustable and readily displaced in the direction of transcription by the transcriptional machinery. We propose that such robust but flexible tethering allows the axial element to promote recombination while easily adapting to changes in chromosome activity. 7 genome wide meiotic ChIP-seq sets: V5-Red1 DNA interaction (V5-Red1-ChIP), V5-Red1 DNA interaction in the absence of axis protein Hop1 (V5-Red1-ChIP, hop1delta), V5-Red1 DNA interaction in the absence of another two axis proteins Hop1 and Rec8 (V5-Red1-ChIP, hop1delta rec8delta), Rec8-HA DNA interaction (Rec8-HA-ChIP), Rec8-HA DNA interactionin the absence of Red1 (Rec8-HA-ChIP, red1delta), and 2 untagged control (V5-untagged-ChIP, HA-untagged-ChIP) (corresponding to the main Figure5)
2015-08-07 | E-GEOD-70112 | biostudies-arrayexpress
Project description:Two pathways drive meiotic chromosome axis assembly in Saccharomyces cerevisiae
| PRJNA656527 | ENA