Similar Datasets
Project description:The temporal order of DNA replication along chromosomes is reorganized in the context of cell differentiation and disease states and is thought to reflect transcriptional competence of the genome. During differentiation of mouse 3T3-L1 cells into adipocytes, cells undergo one or two rounds of cell division called mitotic clonal expansion (MCE). MCE is an essential step for adipogenesis; however, little is known about the regulation of DNA replication during this period. Here, we performed genome-wide mapping of replication timing (RT) in mouse 3T3-L1 cells before and during MCE and identified a number of chromosomal regions shifting toward either earlier or later replication through two rounds of replication. These RT changes were confirmed in individual cells by single-cell DNA replication sequencing. Coordinate changes between a shift toward earlier replication and transcriptional activation of adipogenesis-associated genes were observed. RT changes occur before full expression of these genes, indicating that RT reorganization may contribute to the mature adipocyte phenotype. To support this, cells undergoing two rounds of DNA replication during MCE have higher potential to differentiate into lipid droplet-accumulating adipocytes, compared with cells undergoing a single round of DNA replication and non-replicating cells.
2022-12-22 | GSE216765 | GEO
Project description:The temporal order of DNA replication along chromosomes is reorganized in the context of cell differentiation and disease states and is thought to reflect transcriptional competence of the genome. During differentiation of mouse 3T3-L1 cells into adipocytes, cells undergo one or two rounds of cell division called mitotic clonal expansion (MCE). MCE is an essential step for adipogenesis; however, little is known about the regulation of DNA replication during this period. Here, we performed genome-wide mapping of replication timing (RT) in mouse 3T3-L1 cells before and during MCE and identified a number of chromosomal regions shifting toward either earlier or later replication through two rounds of replication. These RT changes were confirmed in individual cells by single-cell DNA replication sequencing. Coordinate changes between a shift toward earlier replication and transcriptional activation of adipogenesis-associated genes were observed. RT changes occur before full expression of these genes, indicating that RT reorganization may contribute to the mature adipocyte phenotype. To support this, cells undergoing two rounds of DNA replication during MCE have higher potential to differentiate into lipid droplet-accumulating adipocytes, compared with cells undergoing a single round of DNA replication and non-replicating cells.
2022-12-22 | GSE216767 | GEO
Project description:Reorganization of the DNA replication landscape during mitotic clonal expansion is closely linked with adipogenic gene expression
| PRJNA895357 | ENA
Project description:Reorganization of the DNA replication landscape during mitotic clonal expansion is closely linked with adipogenic gene expression [RNA-seq]
| PRJNA895350 | ENA
Project description:Reorganization of the DNA replication landscape during mitotic clonal expansion is closely linked with adipogenic gene expression [E/L Repli-seq (BrdUIP), scRepli-seq]
| PRJNA895359 | ENA
Project description:The fat mass and obesity-associated (FTO) gene plays a pivotal role in regulating body weight and fat mass; however, the underlying mechanisms are poorly understood. Here we show that primary adipocytes and mouse embryonic fibroblasts (MEFs) derived from FTO overexpression (FTO-4) mice exhibit increased potential for adipogenic differentiation, while MEFs derived from FTO knockout (FTO-KO) mice show reduced adipogenesis. As predicted from these findings, fat pads from FTO-4 mice fed a high-fat diet show more numerous adipocytes. FTO influences adipogenesis by regulating events early in adipogenesis, during the process of mitotic clonal expansion. The effect of FTO on adipogenesis appears to be mediated via enhanced expression of the pro-adipogenic short isoform of RUNX1T1, which enhanced adipocyte proliferation, and is increased in FTO-4 MEFs and reduced in FTO-KO MEFs. Our findings provide novel mechanistic insight into how upregulation of FTO leads to obesity.
| S-EPMC4410642 | biostudies-literature
Project description:Adipocyte differentiation is orchestrated by the ligand-activated nuclear receptor PPARγ. Endogenous ligands comprise oxidized derivatives of arachidonic acid and structurally similar PUFAs. Although expression of PPARγ peaks in mature adipocytes, ligands are produced primarily at the onset of differentiation. Concomitant with agonist production, murine fibroblasts undergo two rounds of mitosis referred to as mitotic clonal expansion. Here we show that mouse embryonic fibroblasts deficient in either of two cell cycle inhibitors, the transcription factor p53 or its target gene encoding the cyclin-dependent kinase inhibitor p21, exhibit increased adipogenic potential. The antiadipogenic effect of p53 relied on its transcriptional activity and p21 expression but was circumvented by administration of an exogenous PPARγ agonist suggesting a linkage between cell cycling and PPARγ ligand production. Indeed, cell cycle inhibitory compounds decreased PPARγ ligand production in differentiating 3T3-L1 preadipocytes. Furthermore, these inhibitors abolished the release of arachidonic acid induced by the hormonal cocktail initiating adipogenesis. Collectively, our results suggest that murine fibroblasts require clonal expansion for PPARγ ligand production at the onset of adipocyte differentiation.
| S-EPMC4242442 | biostudies-literature
Project description:ObjectivesRNF20 is recognized as a main E3 ligase for monoubiquitination of histone H2B at lysine 120 (H2Bub). The critical role of RNF20 and H2Bub in various molecular events, such as DNA replication, RNA transcription, and DNA damage response, has been widely investigated and documented. However, its role in porcine adipogenesis remains unknown. In this study, we aimed to clarify the effect of RNF20 on porcine preadipocyte differentiation.Materials and methodsBackfat tissues from fat-type pigs (Bama and Meishan) and lean-type pigs (Yorkshire and Landrace) were collected to detect the expression level of RNF20. Preadipocytes were isolated from Bama piglets and induced to differentiation. Small interfering RNAs were applied to deplete RNF20. Oil Red O staining, quantitative real-time PCR, RNA-seq, Western blot analysis, and EdU assays were performed to study the regulatory mechanism of RNF20 during adipogenesis.ResultsWe found that the expression levels of RNF20 and H2Bub were significantly higher in backfat tissues from fat-type pigs than in those from lean-type pigs. Consistently, the significantly induced expression of RNF20 and H2Bub was also observed in porcine differentiated adipocytes. In addition, knockdown of RNF20 greatly inhibited porcine adipogenesis, as evidenced by dramatically decreased lipid droplet formation and lower expression levels of adipogenic transcription masters in RNF20 knockdown cells. Mechanistically, the depletion of RNF20 decreases the cell proliferation and the level of p-C/EBPβ via the Ras-Raf-MEK1/2-ERK1/2 cascade pathway at the mitotic clonal expansion phase and therefore suppresses cell differentiation.ConclusionsOur results demonstrate that RNF20 is required for porcine preadipocyte differentiation.
| S-EPMC8666272 | biostudies-literature
Project description:Preadipocytes initiate differentiation into adipocytes through a cascade of events. Mitotic clonal expansion, as one of the earliest events, is essential for adipogenesis. However, the underlying mechanisms that regulate mitotic clonal expansion remain elusive. SIRT6 is a member of the evolutionarily conserved sirtuin family of nicotinamide adenine dinucleotide (NAD)+-dependent protein deacetylases. Here, we show that SIRT6 deficiency in preadipocytes blocks their adipogenesis. Analysis of gene expression during adipogenesis reveals that KIF5C, which belongs to the kinesin family, is negatively regulated by SIRT6. Furthermore, we show that KIF5C is a negative factor for adipogenesis through interacting with CK2α', a catalytic subunit of CK2. This interaction blocks CK2α' nuclear translocation and CK2 kinase activity and inhibits mitotic clonal expansion during adipogenesis. These findings reveal a crucial role of SIRT6 in adipogenesis and provide potential therapeutic targets for obesity.
| S-EPMC9396928 | biostudies-literature
Project description:CCAAT enhancer binding protein ? (C/EBP?) is required for both mitotic clonal expansion (MCE) and terminal differentiation during the 3T3-L1 adipocyte differentiation program. Whereas the mechanism of C/EBP? during terminal differentiation is well understood, the mechanism of C/EBP? in MCE is not. We provide evidence that histone H4, the most conserved cell cycle-related histone, the change of which is strictly correlated with DNA content change during the cell cycle, is transcriptionally activated by C/EBP? during MCE. Expression of histone H4 is increased at 16 h after induction when 3T3-L1 preadipocytes synchronously reenter S phase, which is correlated with the sequential phosphorylation and activation of C/EBP?, and expression was partially suppressed when A-C/EBP (dominant negative for C/EBP protein) was overexpressed. One C/EBP-binding site was identified in one of the histone H4 gene promoters (hist4h4), confirmed by both electrophoretic mobility shift assay and chromatin immunoprecipitation assay. C/EBP-binding sites were also found in 9 of 11 other histone H4 promoters, which can also be transactivated by C/EBP?. Knockdown of C/EBP? by stealth small interfering RNA partially decreased H4 gene expression and arrested cells in G1 phase as indicated by bromodeoxyuridine incorporation and fluorescence-activated cell sorting analysis of DNA content. This study provides new insights into why C/EBP? is required for MCE during 3T3-L1 adipocyte differentiation and why C/EBP? plays important roles in the proliferation of other cell types.
| S-EPMC3128520 | biostudies-literature