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Abstract BackgroundEpigenetic processes are proposed to be a mechanism regulating gene expression during phenotypic plasticity. However, environmentally induced changes in DNA methylation exhibit little-to-no association with differential gene expression in metazoans at a transcriptome-wide level. It remains unexplored whether associations between environmentally induced differential methylation and expression are contingent upon other epigenomic processes such as chromatin accessibility. We quantified methylation and gene expression in larvae of the purple sea urchinStrongylocentrotus purpuratusexposed to different ecologically relevant conditions during gametogenesis (maternal conditioning) and modeled changes in gene expression and splicing resulting from maternal conditioning as functions of differential methylation, incorporating covariates for genomic features and chromatin accessibility. We detected significant interactions between differential methylation, chromatin accessibility, and genic feature type associated with differential expression and splicing. ResultsDifferential gene body methylation had significantly stronger effects on expression among genes with poorly accessible transcriptional start sites while baseline transcript abundance influenced the direction of this effect. Transcriptional responses to maternal conditioning were 4–13 × more likely when accounting for interactions between methylation and chromatin accessibility, demonstrating that the relationship between differential methylation and gene regulation is partially explained by chromatin state. ConclusionsDNA methylation likely possesses multiple associations with gene regulation during transgenerational plasticity inS. purpuratusand potentially other metazoans,but its effects are dependent on chromatin accessibility and underlying genic features.
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Characterization of p53/p63/p73 and Myc expressions during embryogenesis of the sea urchin
Abstract BackgroundSome marine invertebrate organisms are considered not to develop tumors due to unknown mechanisms. To gain an initial insight into how tumor‐related genes may be expressed and function during marine invertebrate development, we here leverage sea urchin embryos as a model system and characterize the expressions of Myc and p53/p63/p73 which are reported to function synergistically in mammalian models as an oncogene and tumor suppressor, respectively. ResultsDuring sea urchin embryogenesis, a combo gene of p53/p63/p73 is found to be maternally loaded and decrease after fertilization both in transcript and protein, while Myc transcript and protein are zygotically expressed. p53/p63/p73 and Myc proteins are observed in the cytoplasm and nucleus of every blastomere, respectively, throughout embryogenesis. Both p53/p63/p73 and Myc overexpression results in compromised development with increased DNA damage after the blastula stage. p53/p63/p73 increases the expression ofparp1, a DNA repair/cell death marker gene, and suppresses endomesoderm gene expressions. In contrast, Myc does not alter the expression of specification genes or oncogenes yet induces disorganized morphology. Conclusionsp53/p63/p73 appears to be important for controlling cell differentiation, while Myc induces disorganized morphology yet not through conventional oncogene regulations or apoptotic pathways during embryogenesis of the sea urchin.
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- Award ID(s):
- 1940975
- PAR ID:
- 10493516
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Developmental Dynamics
- Volume:
- 253
- Issue:
- 3
- ISSN:
- 1058-8388
- Format(s):
- Medium: X Size: p. 333-350
- Size(s):
- p. 333-350
- Sponsoring Org:
- National Science Foundation
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