Hierarchical dinucleotide distribution in genome along evolution and its effect on chromatin packing.
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ABSTRACT:
SUBMITTER: Cai Z
PROVIDER: S-EPMC8321668 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The three dimensional folding of mammalian genomes is cell-type specific and hard to convert suggesting that it is an important layer of gene regulation. Analysis of genome-wide chromosomal associations revealed adipogenesis-specific spatial clustering of adipogenic genes in 3T3-L1 cells. High temporal resolution analysis revealed that the adipogenic "hub", sampled by pparg and Lpin1, undergoes orchestrated reorganization along adipogenesis. Coupling the dynamics of genome architecture with multiple chromatin datasets, points that among all transcription factors tested, RXR is central in genome reorganization at the beginning of adipogenesis. Interestingly, at the end of differentiation the adipogenic hub is shifted to H3K27me3 repressive environment in conjunction with attenuation of gene transcription. Together, we propose stage-specific hierarchy among the orchestra of transcription factors contributing to the establishment of the adipogenic genome architecture that brings together the adipogenic genetic program. In addition, the repositioning to H3K27me3 environment in the end of the differentiation may contribute to stabilize gene expression levels and diminish the developmental plasticity of the specialize cell.
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