In mammals, the nuclear lamina interacts with hundreds of large genomic regions, termed lamina-associated domains (LADs) that are generally in a transcriptionally repressed state. Lamins form the major structural component of the lamina and have been reported to bind DNA and chromatin. Here we systematically evaluated whether lamins are necessary for the peripheral localization of LADs in murine embryonic stem cells. Surprisingly, removal of essentially all lamins did not have any detectable effect on the genome-wide interaction pattern of chromatin with the inner nuclear membrane. This suggests that other components of the inner nuclear membrane mediate these interactions. Overall design: 2 samples, each with a biological replicate: wt mESC, B type lamin null (dKO) dKO mESC
Nuclear lamins are not required for lamina-associated domain organization in mouse embryonic stem cells.
No sample metadata fields
View SamplesThe eukaryotic genome is organized in a three-dimensional structure called chromatin, constituted by DNA and associated proteins, the majority of which are histones. Post-translational modifications of histone proteins greatly influence chromatin structure and regulate many DNA-based biological processes. Methylation of lysine 36 of histone 3 (H3K36) is a post-translational modification functionally relevant during early steps of DNA damage repair. Here, we show that the JMJD-5 regulates H3K36 di-methylation and it is required at late stages of double strand break repair mediated by homologous recombination. Loss of jmjd-5 results in hypersensitivity to ionizing radiation and in meiotic defects, and it is associated with aberrant retention of RAD-51 at sites of double strand breaks. Analyses of jmjd-5 genetic interactions with genes required for resolving recombination intermediates (rtel-1) or promoting the resolution of RAD-51 double stranded DNA filaments (rfs-1 and helq-1) suggest that jmjd-5 prevents the formation of stalled postsynaptic recombination intermediates and favors RAD-51 removal. As these phenotypes are all recapitulated by a catalytically inactive jmjd-5 mutant, we propose a novel role for H3K36me2 regulation during late steps of homologous recombination critical to preserve genome integrity. Overall design: RNA sequencing of N2 and jmjd-5(tm3735) at 20C and 25C at generation 1 (G1) and generation 6 (G6)
JMJD-5/KDM8 regulates H3K36me2 and is required for late steps of homologous recombination and genome integrity.
Subject
View SamplesThe spatial organization of chromosomes influences many nuclear processes including gene expression. The cohesin complex shapes the 3D genome by looping together CTCF sites along chromosomes. We show here that chromatin loop size can be increased, and that the duration with which cohesin embraces DNA determines the degree to which loops are enlarged. Cohesin's DNA release factor WAPL restricts the degree of this loop extension and also prevents looping between incorrectly oriented CTCF sites. We reveal that the SCC2/SCC4 complex promotes the extension of chromatin loops and the formation of topologically associated domains (TADs). Our data support the model that cohesin structures chromosomes through the processive enlargement of loops and that TADs reflect polyclonal collections of loops in the making. Finally, we find that whereas cohesin promotes chromosomal looping, it rather limits nuclear compartmentalization. We conclude that the balanced activity of SCC2/SCC4 and WAPL enables cohesin to correctly structure chromosomes. Overall design: RNAseq was performed in control, ?WAPL 3.3, ?WAPL 1.14, ?SCC4 and ?WAPL/?SCC4 cells in triplicate.
The Cohesin Release Factor WAPL Restricts Chromatin Loop Extension.
Cell line, Subject
View SamplesMammalian interphase chromosomes interact with the nuclear lamina (NL) through hundreds of large Lamina Associated Domains (LADs). We report a method to map NL contacts genome-wide in single human cells. Analysis of ~400 maps reveals a core architecture of gene-poor LADs that contact the NL with high cell-to-cell consistency, interspersed by LADs with more variable NL interactions. The variable contacts are more sensitive to a change in genome ploidy than the consistent contacts. Single-cell maps indicate that NL contacts involve multivalent interactions over hundreds of kilobases. Moreover, we observe extensive intra-chromosomal coordination of NL contacts, even over tens of megabases. Such coordinated loci exhibit preferential interactions as detected by Hi-C. Finally, single-cell gene expression and chromatin accessibility analysis shows that loci with consistent NL contacts are expressed at lower levels and are more consistently inaccessible than loci with lower contact frequencies. These results highlight fundamental principles of single cell chromatin organization. Overall design: In this dataset, single-cell mRNA sequencing results from 96 single KBM7 cells have been deposited
Genome-wide maps of nuclear lamina interactions in single human cells.
No sample metadata fields
View SamplesSeveral different mechanical signals have been proposed to control the extent and pattern of myocardial growth and remodeling, though this has largely been studied using in vitro model systems that are not representative of intact myocardium or in vivo models in which isolating the effects of individual candidate stimuli is exceedigly difficult. We used a unique tissue culture system that allows the simultaneous control of multiple mechanical inputs and other potentially confounding stimuli (e.g., hormonal).
Effects of stretch and shortening on gene expression in intact myocardium.
Sex, Age
View SamplesExpression data from antigen-experienced Nfat1+/+ and Nfat1-/- CD4+ T cells following 21 days of Plasmodium yoelii 17XNL infection.
The Transcription Factor NFAT1 Participates in the Induction of CD4<sup>+</sup> T Cell Functional Exhaustion during Plasmodium yoelii Infection.
Sex, Specimen part
View SamplesAutism spectrum disorder (ASD) is a disorder of brain development believed, in most cases, to be of genetic origin. We use induced pluripotent stem cells (iPSCs)-derived 3-dimensional neural cultures (organoids) in patients with ASD and macrocephaly to investigate neurodevelopmental alterations that cause this form of ASD. By using transcriptome analyses, we identified modules of co-expressed genes significantly upregulated in ASD patients compared to non-ASD first-degree family members. Overall design: Total RNA was prepared from terminal differentiation day 0, 11 and 31 of iPSCs-derived neural cultures from ASD patients and non-ASD first-degree family members. A total of 4 patients and 8 controls (unaffected family members) were analyzed in replicates (two to three iPSC clones per person).
FOXG1-Dependent Dysregulation of GABA/Glutamate Neuron Differentiation in Autism Spectrum Disorders.
No sample metadata fields
View SamplesFoxO6 is expressed in the brain, craniofacial region and somite, but the precise role of FoxO6 in craniofacial development remain unknown. We found that FoxO6 is expressed specifically in craniofacial tissues and FoxO6-/- mice undergo expansion of the face, frontal cortex, olfactory component and skull.
FoxO6 regulates Hippo signaling and growth of the craniofacial complex.
Specimen part
View SamplesIn this study, we assess the effect of zoledronic acid on clearance of disseminated tumour cells (DTCs) from the bone marrow in women undergoing neoadjuvant chemotherapy for breast cancer
CXCR4 Protein Epitope Mimetic Antagonist POL5551 Disrupts Metastasis and Enhances Chemotherapy Effect in Triple-Negative Breast Cancer.
Specimen part
View SamplesMicroRNAs (miRNAs) regulate many basic aspects of cell biology including neuronal plasticity, but little is known of their roles in drug addiction. Extended access to cocaine can trigger the emergence of compulsive drug-seeking behaviors, but molecular mechanisms regulating this process remain unclear. Here we report that microRNA-212 (miR-212) is upregulated in the dorsal striatum of rats with extended access to cocaine. Striatal overexpression of miR-212 decreases, whereas its inhibition increases cocaine intake in rats with extended but not restricted drug access, suggesting that miR-212 serves as a protective factor against the development of compulsive drug seeking. The transcription factor CREB (cAMP response element-binding protein) is considered a core regulator of cocaine reward. We show that miR-212 controls responsiveness to cocaine by dramatically amplifying striatal CREB signaling. This action occurs through miR-212-enhanced Raf-1 activity, resulting in adenylyl cyclase sensitization and increased expression of the essential CREB co-activator TORC (Transducer of Regulated CREB; also known as CRTC). Our findings suggest that striatal miR-212 signaling plays a key role in vulnerability to addiction, and that noncoding RNAs such as the miRNAs may serve as novel targets for the development of anti-addiction therapeutics.
Striatal microRNA controls cocaine intake through CREB signalling.
Sex, Specimen part, Cell line
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