Chromatin binding by HORMAD proteins regulates meiotic recombination initiation
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA934068 | ENA |
REPOSITORIES: ENA
Similar Datasets
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:Orderly segregation of chromosomes during meiosis requires that crossovers form between homologous chromosomes by recombination. Programmed DNA double-strand breaks (DSBs) initiate meiotic recombination. We identify ANKRD31 as a critical component of complexes of DSB-promoting proteins which assemble on meiotic chromosome axes. Genome-wide, ANKRD31 deficiency causes delayed recombination initiation. In addition, loss of ANKRD31 alters DSB distribution owing to reduced selectivity for sites that normally attract DSBs. Strikingly, ANKRD31 deficiency also abolishes uniquely high rates of recombination that normally characterize pseudoautosomal regions (PARs) of X and Y chromosomes. Consequently, sex chromosomes do not form crossovers leading to chromosome segregation failure in ANKRD31-deficient spermatocytes. These defects are accompanied by a genome-wide delay in assembling DSB-promoting proteins on axes and a loss of a pecialized PAR-axis domain that is highly enriched for DSB-promoting proteins. Thus, we propose a model for spatiotemporal patterning of recombination by ANKRD31-dependent control of axis-associated complexes of DSB-promoting proteins.
2019-06-07 | GSE126443 | GEO
Project description:Meiotic homologous recombination is a critical DNA-templated event for sexually-reproducing organisms. It is initiated by a programmed formation of DNA double strand breaks (DSBs), mainly formed at recombination hotspots, and is, like all other DNA-related processes, under great influence of chromatin structure. For example, local chromatin around hotspots directly impacts DSB formation. In addition, DSB is proposed to occur in a higher-order chromatin architecture termed “axis-loop”, in which many loops protrude from proteinaceous axis. Despite many recent insightful studies, still much remains unknown about how meiotic DSBs are generated in chromatin structure. Here, we show that the highly conserved histone H2A variant H2A.Z promotes meiotic DSB formation in fission yeast. Subsequent investigation revealed that H2A.Z is neither enriched around hotspots nor axis sites, and that transcript levels of DSB-promoting factors were maintained in the absence of H2A.Z. Instead, we found that H2A.Z facilitates chromatin binding of various proteins required for DSB formation. Strikingly, artificial tethering of one of such proteins, Rec10, to chromatin partially restored DSB reduction in H2A.Z-lacking cells. Based on these, we conclude that fission yeast H2A.Z promotes initiation of meiotic recombination partly through delivering DSB-related proteins onto chromatin.
2017-10-24 | GSE81776 | GEO
Project description:Meiotic homologous recombination is a critical DNA-templated event for sexually-reproducing organisms. It is initiated by a programmed formation of DNA double strand breaks (DSBs), mainly formed at recombination hotspots, and is, like all other DNA-related processes, under great influence of chromatin structure. For example, local chromatin around hotspots directly impacts DSB formation. In addition, DSB is proposed to occur in a higher-order chromatin architecture termed “axis-loop”, in which many loops protrude from proteinaceous axis. Despite many recent insightful studies, still much remains unknown about how meiotic DSBs are generated in chromatin structure. Here, we show that the highly conserved histone H2A variant H2A.Z promotes meiotic DSB formation in fission yeast. Subsequent investigation revealed that H2A.Z is neither enriched around hotspots nor axis sites, and that transcript levels of DSB-promoting factors were maintained in the absence of H2A.Z. Instead, we found that H2A.Z facilitates chromatin binding of various proteins required for DSB formation. Strikingly, artificial tethering of one of such proteins, Rec10, to chromatin partially restored DSB reduction in H2A.Z-lacking cells. Based on these, we conclude that fission yeast H2A.Z promotes initiation of meiotic recombination partly through delivering DSB-related proteins onto chromatin.
2017-10-24 | GSE81775 | GEO
Project description:Meiotic recombination differs between males and females, however, when and how these differences are established is unknown. We identify extensive sex differences at recombination initiation by mapping hotspots of meiotic DNA double strand breaks in male and female mice. Contrary to past findings in humans, few hotspots are used uniquely in either sex. Instead, grossly different recombination landscapes result from up to 15-fold differences in hotspot use between males and females. Indeed, most recombination occurs at sex-biased hotspots. Sex biased hotspots appear to be partly determined by chromosome structure, and DNA methylation, absent in females at the onset of meiosis, plays a substantial role. Sex differences are also evident later in meiosis as the repair frequency of distal meiotic breaks as crossovers diverges in males and females. Suppression of distal crossovers may help to minimize age-related aneuploidy that arises due to cohesion loss during dictyate arrest in females.
2018-09-20 | GSE99921 | GEO
Project description:The histone variant H2A.Z promotes initiation of meiotic recombination
| PRJNA322524 | ENA
Project description:To investigate the relationship between meiotic recombination initiation and H3K4m3 in Arabidopsis, we generated and sequenced H3K4m3 ChIP libraries from meiotic stage floral buds in wild type, arp6 and met1. To produce high-resolution of H3K4m3 mapping, we used micrococcal nuclease (MNase) to digest chromatins that were cross-linked by formaldehyde for ChIP. This experiment provides for H3K4m3 maps with the resolution of mononucleosomal DNA level (~150 bp).
2017-06-05 | E-MTAB-5048 | biostudies-arrayexpress
Project description:To determine meiotic recombination initiation sites in Arabidopsis thaliana genome we purified and sequenced oligonucleotides (35-45 nt) bound to SPO11-1, meiosis specific transesterase that induces meiotic DSB formation. This reveals that SPO11-1-oligonucleotide hotspots occur at nucleosome depleted regions of gene promoters, introns, terminators and specific families of DNA transposons (recomposons). To investigate the influence of chromatin structure and epigenetic factors on meiotic DSB formation we performed sequencing of SPO11-1-oligonucleotides in arp6, met1 and suvh4 suvh5 suvh6.
2017-06-05 | E-MTAB-5041 | biostudies-arrayexpress
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 the enrichment of axis proteins at nucleosome-rich 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 localized reduction of axis protein binding and meiotic DNA double-strand breaks (DSBs) in axis islands and leads to defects in chromosome synapsis. Synthetic effects with mutants of the Hop1 regulator 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 the CBR, suggesting that the mechanisms we uncover are broadly conserved.
| S-EPMC10907721 | biostudies-literature
Project description:Several protein ensembles facilitate meiotic crossover recombination and the associated process of synaptonemal complex (SC) assembly during meiosis. We have employed proximity labeling as a phenotyping tool to investigate functional requirements for spatial relationships between meiotic recombination and SC proteins in S. cerevisiae, and to gain deeper insight into the molecular deficits of crossover-deficient meiotic mutants. We find that recombination initiation and synaptonemal complex structures are dispensable for proximity labeling of the Zip3 E3 ligase by components of the ZZS ensemble (Zip2, Zip4 and Spo16) but enzymes associated with early steps in recombination are required for Zip3 proximity labeling by MutSg, consistent with the possibility that MutSg joins Zip3 only after a specific recombination intermediate has been generated. Proximity labeling furthermore suggests that a key defect of crossover-defective, SC-proficient zip1 separation-of-function mutants is a failure to assemble an early recombination ensemble where MutSg can properly engage Zip3. We also find that the SC structural protein Ecm11 is proximity labeled by ZZS proteins in a Zip4-dependent and Zip1-independent manner, but by Zip3 and Msh4 at least in part via a distinct pathway that relies on Zip1. Finally, streptavidin pulldown followed by mass spectrometry on eleven proximity labeling strains uncovered shared proximity targets of SC and crossover-associated proteins, some of which have not yet been implicated in meiotic recombination or SC formation highlighting the potential of proximity labeling as a discovery tool.
2024-10-02 | PXD053621 | Pride