Similar Datasets
Project description:The adult mammalian heart has limited capacity for regeneration following injury, whereas the neonatal heart can readily regenerate within a short period after birth. To uncover the molecular mechanisms underlying neonatal heart regeneration, we compared the transcriptomes and epigenomes of regenerative and nonregenerative mouse hearts over a 7-d time period following myocardial infarction injury. By integrating gene expression profiles with histone marks associated with active or repressed chromatin, we identified transcriptional programs underlying neonatal heart regeneration, and the blockade to regeneration in later life. Our results reveal a unique immune response in regenerative hearts and a retained embryonic cardiogenic gene program that is active during neonatal heart regeneration. Among the unique immune factors and embryonic genes associated with cardiac regeneration, we identified Ccl24, which encodes a cytokine, and Igf2bp3, which encodes an RNA-binding protein, as previously unrecognized regulators of cardiomyocyte proliferation. Our data provide insights into the molecular basis of neonatal heart regeneration and identify genes that can be modulated to promote heart regeneration.
| S-EPMC6744882 | biostudies-literature
Project description:Mechanistic basis of neonatal heart regeneration revealed by transcriptome and histone modification profiling
| PRJNA510088 | ENA
Project description:Transcriptome profiling of neonatal heart regeneration
| PRJNA510091 | ENA
Project description:Background: The adult mammalian heart has limited capacity for regeneration following injury, whereas the neonatal heart can readily regenerate within a short period after birth. To uncover the molecular mechanisms underlying neonatal heart regeneration, we compared the transcriptomes and epigenomes of regenerative and non-regenerative mouse hearts over a 7-day time period following myocardial infarction. Methods: RNA-Seq, H3K27ac ChIP-Seq and H3K27me3 ChIP-Seq were performed on ventricular samples from regenerative P1 or non-regenerative P8 mouse hearts at +1.5d, +3d and +7d after MI or Sham surgery to assemble the transcriptome, active chromatin and repressed chromatin landscapes during neonatal heart regeneration. Dynamic enhancer landscapes from mouse hearts during cardiac development were analyzed using data from ENCODE. Effects on cardiomyocyte proliferation and cardiac function from selected factors identified in this study were tested using BrdU/EdU pulse-labeling or mouse models coupled with immunohistochemistry and echocardiography. Results: By integrating gene expression profiles with histone marks associated with active or repressed chromatin, we identified transcriptional programs underlying neonatal heart regeneration and the blockade to regeneration in later life. Our results reveal a unique immune response in regenerative hearts and an embryonic cardiogenic gene program that remains active during neonatal heart regeneration. Among the unique immune factors and embryonic genes associated with cardiac regeneration, we identified Ccl24, which encodes a cytokine, and Igf2bp3, which encodes an RNA-binding protein, as previously unrecognized regulators of cardiomyocyte proliferation. Conclusions: Our data provide insights into the molecular basis of neonatal heart regeneration and identify genes that might be modulated to promote heart regeneration.
2019-07-15 | GSE123863 | GEO
Project description:Chromatin regulation is a principal mechanism governing animal development, yet it is unclear to what extent structural changes in chromatin underlie tissue regeneration. Non-mammalian vertebrates such as zebrafish activate cardiomyocyte (CM) division after tissue damage to regenerate lost heart muscle. Here, we generated transgenic zebrafish expressing a biotinylatable H3.3 histone variant in CMs and derived cell-type-specific profiles of histone replacement. We identified an emerging program of putative enhancers that revise H3.3 occupancy during regeneration, overlaid upon a genome-wide reduction of H3.3 from promoters. In transgenic reporter lines, H3.3-enriched elements directed gene expression in subpopulations of CMs. Other elements increased H3.3 enrichment and displayed enhancer activity in settings of injury- and/or Neuregulin1-elicited CM proliferation. Dozens of consensus sequence motifs containing predicted transcription factor binding sites were enriched in genomic regions with regeneration-responsive H3.3 occupancy. Thus, cell-type-specific regulatory programs of tissue regeneration can be revealed by genome-wide H3.3 profiling.
| S-EPMC5367476 | biostudies-literature
Project description:Epigenome profiling of neonatal heart regeneration
| PRJNA510092 | ENA
Project description:Background: The adult mammalian heart has limited capacity for regeneration following injury, whereas the neonatal heart can readily regenerate within a short period after birth. To uncover the molecular mechanisms underlying neonatal heart regeneration, we compared the transcriptomes and epigenomes of regenerative and non-regenerative mouse hearts over a 7-day time period following myocardial infarction. Methods: RNA-Seq, H3K27ac ChIP-Seq and H3K27me3 ChIP-Seq were performed on ventricular samples from regenerative P1 or non-regenerative P8 mouse hearts at +1.5d, +3d and +7d after MI or Sham surgery to assemble the transcriptome, active chromatin and repressed chromatin landscapes during neonatal heart regeneration. Dynamic enhancer landscapes from mouse hearts during cardiac development were analyzed using data from ENCODE. Effects on cardiomyocyte proliferation and cardiac function from selected factors identified in this study were tested using BrdU/EdU pulse-labeling or mouse models coupled with immunohistochemistry and echocardiography. Results: By integrating gene expression profiles with histone marks associated with active or repressed chromatin, we identified transcriptional programs underlying neonatal heart regeneration and the blockade to regeneration in later life. Our results reveal a unique immune response in regenerative hearts and an embryonic cardiogenic gene program that remains active during neonatal heart regeneration. Among the unique immune factors and embryonic genes associated with cardiac regeneration, we identified Ccl24, which encodes a cytokine, and Igf2bp3, which encodes an RNA-binding protein, as previously unrecognized regulators of cardiomyocyte proliferation. Conclusions: Our data provide insights into the molecular basis of neonatal heart regeneration and identify genes that might be modulated to promote heart regeneration.
2019-07-15 | GSE123867 | GEO
Project description:Global proteomics data captured from P8 hearts, 7 days post-MI or sham surgery. Hearts were treated at 4, 5, and 6 days post surgery with saline or rapamycin.
2023-07-13 | MSV000092436 | MassIVE
Project description:BACKGROUND: The activity of a single gene is influenced by the composition of the chromatin in which it is embedded. Nucleosome turnover, conformational dynamics, and covalent histone modifications each induce changes in the structure of chromatin and its affinity for regulatory proteins. The dynamics of histone modifications and the persistence of modification patterns for long periods are still largely unknown. RESULTS: In this study, we present a stochastic mathematical model that describes the molecular mechanisms of histone modification pattern formation along a single gene, with non-phenomenological, physical parameters. We find that diffusion and recruitment properties of histone modifying enzymes together with chromatin connectivity allow for a rich repertoire of stochastic histone modification dynamics and pattern formation. We demonstrate that histone modification patterns at a single gene can be established or removed within a few minutes through diffusion and weak recruitment mechanisms of histone modification spreading. Moreover, we show that strong synergism between diffusion and weak recruitment mechanisms leads to nearly irreversible transitions in histone modification patterns providing stable patterns. In the absence of chromatin connectivity spontaneous and dynamic histone modification boundaries can be formed that are highly unstable, and spontaneous fluctuations cause them to diffuse randomly. Chromatin connectivity destabilizes this synergistic system and introduces bistability, illustrating state switching between opposing modification states of the model gene. The observed bistable long-range and localized pattern formation are critical effectors of gene expression regulation. CONCLUSION: This study illustrates how the cooperative interactions between regulatory proteins and the chromatin state generate complex stochastic dynamics of gene expression regulation.
| S-EPMC4234852 | biostudies-other
Project description:Neonates have dampened expression of pro-inflammatory cytokines and difficulty clearing pathogens. This makes them uniquely susceptible to infections, but the factors regulating neonatal-specific immune responses are poorly understood. Epigenetics, including histone modifications, can activate or silence gene transcription by modulating chromatin structure and stability without affecting the DNA sequence itself and are potentially modifiable. Histone modifications are known to regulate immune cell differentiation and function in adults but have not been well studied in neonates.To elucidate the role of histone modifications in neonatal immune function, we performed chromatin immunoprecipitation on mononuclear cells from 45 healthy neonates (gestational ages 23-40 weeks). As gestation approached term, there was increased activating H3K4me3 on the pro-inflammatory IL1B, IL6, IL12B, and TNF cytokine promoters (p?<?0.01) with no change in repressive H3K27me3, suggesting that these promoters in preterm neonates are less open and accessible to transcription factors than in term neonates. Chromatin immunoprecipitation with massively parallel DNA sequencing (ChIP-seq) was then performed to establish the H3K4me3, H3K9me3, H3K27me3, H3K4me1, H3K27ac, and H3K36me3 landscapes in neonatal and adult CD14+ monocytes. As development progressed from neonate to adult, monocytes lost the poised enhancer mark H3K4me1 and gained the activating mark H3K4me3, without a change in additional histone modifications. This decreased H3K4me3 abundance at immunologically important neonatal monocyte gene promoters, including CCR2, CD300C, ILF2, IL1B, and TNF was associated with reduced gene expression.These results provide evidence that neonatal immune cells exist in an epigenetic state that is distinctly different from adults and that this state contributes to neonatal-specific immune responses that leaves them particularly vulnerable to infections.
| S-EPMC5028999 | biostudies-literature