scholarly journals Bmal1- and Per2-mediated Regulation of the Osteogenic Differentiation and Proliferation of Mouse BMSCs by Modulating the Wnt/β-catenin Pathway

2021 ◽  
Author(s):  
Jiawen Zheng ◽  
Lanxin Zhang ◽  
Zhen Tan ◽  
Qing Zhao ◽  
Xiaoyu Wei ◽  
...  
Keyword(s):  
Osteogenic Differentiation ◽  
Clock Genes ◽  
Synergistic Effects ◽  
Underlying Mechanism ◽  
Premature Aging ◽  
Marrow Mesenchymal Stem Cells ◽  
Circadian Clock Genes ◽  
Core Components ◽  
Differentiation And Proliferation ◽  
Severe Degree

Abstract Bmal1 and Per2 are the core components of the circadian clock genes(CCGs). Bmal1−/− mice exhibited premature aging characterized by osteoporosis and reduced proliferation ability. The same thing occurred in Per2−/− mice, albeit to a less severe degree. However, whether the effects of Bmal1 and Per2 on proliferation and osteogenic differentiation are synergistic or antagonistic remains unclear. To figure this out, we constructed lentiviral and adenoviral vectors to silence or overexpress Bmal1 or Per2 in bone marrow mesenchymal stem cells (BMSCs), and applied MTT, flow cytometry, RT-qPCR, WB, and ChIP-Seq analyses to identify the underlying mechanism. The results showed Bmal1 and Per2 had synergistic effects on the proliferation and differentiation of BMSCs. Furthermore, Bmal1 and Per2 inhibited the Wnt/β-catenin signaling pathway, accompanied by downregulating Rorα expression and upregulating Rev-erbα expression, both of which were also key elements of CCGs. This may be the mechanism by which Bmal1 and Per2 negatively regulate the osteogenic differentiation of BMSCs.

scholarly journals Bmal1- and Per2-Mediated Regulation of the Osteogenic Differentiation and Proliferation of Mouse BMSCs by Modulating the Wnt/β-catenin Pathway

2021 ◽  
Author(s):  
Jiawen Zheng ◽  
Lanxin Zhang ◽  
Zhen Tan ◽  
Yuhong Wang ◽  
Qing Zhao ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Osteogenic Differentiation ◽  
Signaling Pathway ◽  
Clock Genes ◽  
Synergistic Effects ◽  
Premature Aging ◽  
Phase Cell ◽  
Expression Change ◽  
Alizarin Red ◽  
Differentiation And Proliferation

Abstract BackgroundBmal1 and Per2 are the core components of the circadian clock genes(CCGs). Bmal1-/- mice exhibit premature aging, as indicated by hypotrichosis and osteoporosis, with a loss of proliferation ability. The same occurs in Per2-/- mice, albeit to a less severe degree. However, whether the effects of Bmal1 and Per2 on proliferation and osteogenic differentiation are synergistic or antagonistic remains unclear. Thus, our study aimed to explore the effects and specific mechanism.Materials and methodsLentiviral and adenoviral vectors were constructed to silence or overexpress Bmal1 or Per2 and MTT, flow cytometry, RT-qPCR, WB, immunohistochemistry, alizarin red staining and ChIP-Seq analyses were applied to identify the possible mechanism. ResultsThe successful knockdown and overexpression of Bmal1/Per2 were detected by fluorescence microcopy. Flow cytometry found out that Bmal1 or Per2 knockdown resulted in G1-phase cell cycle arrest. RT-qPCR showed the different expression levels of Wnt-3a, c-myc1 and axin2 in the Wnt/β-catenin signaling pathway as well as the gene expression change of Rorα and Rev-erbα. Meanwhile, Related proteins such as β-catenin, TCF-1, and P-GSK-3β were detected. ALP activity and the amount of mineral nodules were compared. ChIP-Seq results showed the possible mechanism.ConclusionsBmal1 and Per2, as primary canonical clock genes, showed synergistic effects on the proliferation and differentiation of BMSCs. They would inhibit the Wnt/β-catenin signaling pathway by downregulating Rorα expression or upregulating Rev-erbα expression, both of which were also key elements of CCGs. And this may be the mechanism by which they negatively regulate the osteogenic differentiation of BMSCs.

High glucose inhibits osteogenic differentiation of bone marrow mesenchymal stem cells via regulating miR-493-5p/ZEB2 signalling

2020 ◽  
Vol 167 (6) ◽  
pp. 613-621
Author(s):  
Zhongshu Zhai ◽  
Wanhong Chen ◽  
Qiaosheng Hu ◽  
Xin Wang ◽  
Qing Zhao ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Osteogenic Differentiation ◽  
High Glucose ◽  
Underlying Mechanism ◽  
Luciferase Assay ◽  
Downstream Target ◽  
Marrow Mesenchymal Stem Cells ◽  
Diabetic Osteoporosis

Abstract Diabetic osteoporosis (DOP) is attributed to the aberrant physiological function of bone marrow mesenchymal stem cells (BMSCs) under high glucose (HG) environment. MicroRNAs (miRNAs) are involved in the pathological processes of DOP. We aimed to explore the underlying mechanism of miRNA in DOP. BMSCs were cultured in osteogenic medium with HG to induce osteogenic differentiation, and the interaction between miR-493-5p and ZEB2 was assessed by luciferase assay. Herein, we found miR-493-5p is gradually reduced during osteogenic differentiation in BMSCs. HG treatment inhibits osteogenic differentiation and induces an up-regulation of miR-493-5p leading to reduced level of its downstream target ZEB2. Inhibition of miR-493-5p attenuates HG-induced osteogenic differentiation defects by upregulation of ZEB2. Mechanistically, miR-493-5p/ZEB2 signalling mediates HG-inhibited osteogenic differentiation by inactivation of Wnt/β-catenin signalling. More importantly, knockdown of miR-493-5p therapeutically alleviated the DOP condition in mice. HG prevents BMSCs osteogenic differentiation via up-regulation of miR-493-5p, which results in reduced level of ZEB2 by directly targeting its 3′-untranslated region of mRNA. Thus, miR-493-5p/ZEB2 is a potential therapeutic target and provides novel strategy for the treatment and management of DOP.

Expression of circadian clock genes in retinal dopaminergic cells

2007 ◽  
Vol 24 (4) ◽  
pp. 573-580 ◽  
Author(s):  
RONALD DORENBOS ◽  
MASSIMO CONTINI ◽  
HAJIME HIRASAWA ◽  
STEFANO GUSTINCICH ◽  
ELIO RAVIOLA
Keyword(s):  
Circadian Clock ◽  
Light Adaptation ◽  
Clock Genes ◽  
Negative Control ◽  
Circadian Oscillators ◽  
Interesting Candidate ◽  
Circadian Clock Genes ◽  
Core Components ◽  
A Site

The mammalian neural retina contains single or multiple intrinsic circadian oscillators that can be directly entrained by light cycles. Dopaminergic amacrine (DA) cells represent an especially interesting candidate as a site of the retinal oscillator because of the crucial role of dopamine in light adaptation, and the widespread distribution of dopamine receptors in the retina. We hereby show by single-cell, end-point RT-PCR that retinal DA cells contain the transcripts for six core components of the circadian clock: Bmal1, Clock, Cry1, Cry2, Per1, and Per2. Rod photoreceptors represented a negative control, because they did not appear to contain clock transcripts. We finally confirmed that DA cells contain the protein encoded by the Bmal1 gene by comparing immunostaining of the nuclei of DA cells in the retinas of wildtype and Bmal1−/− mice. It is therefore likely that DA cells contain a circadian clock that anticipates predictable variations in retinal illumination.

scholarly journals Prognostic values of the core components of the mammalian circadian clock in prostate cancer

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12539
Author(s):  
Wenchang Yue ◽  
Xiao Du ◽  
Xuhong Wang ◽  
Niu Gui ◽  
Weijie Zhang ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Risk Score ◽  
Clock Genes ◽  
Predictive Performance ◽  
Lymph Node Status ◽  
Free Survival ◽  
The Core ◽  
Circadian Clock Genes ◽  
Core Components ◽  
Score Model

Background Prostate cancer (PC) is one of the most common malignancies in males. Extensive and complex connections between circadian rhythm and cancer were found. Nonetheless, in PC, the potential role of the core components of the mammalian circadian clock (CCMCCs) in prognosis prediction has not been fully clarified. Methods We firstly collected 605 patients with PC from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Survival analysis was carried out for each CCMCC. Then, we investigated the prognostic ability of CCMCCs by Cox regression analysis. Independent prognostic signatures were extracted for the establishment of the circadian clock-based risk score model. We explored the predictive performance of the risk score model in the TCGA training cohort and the independent GEO dataset. Finally, the relationships between risk score and clinicopathological parameters, biological processes, and signaling pathways were evaluated. Results The expression levels of CCMCCs were widely correlated with age, tumor status, lymph node status, disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS). Nine circadian clock genes, including CSNK1D, BTRC, CLOCK, CSNK1E, FBXL3, PRKAA2, DBP, NR1D2, and RORB, were identified as vital prognostic factors in PC and were used to construct the circadian clock-based risk score model. For DFS, the area under the 3-year or 5-year receiver operating characteristic curves ranged from 0.728 to 0.821, suggesting better predictive performance. When compared with T3-4N1 stage, PC patients at T2N0 stage might be benefited more from the circadian clock-based risk score model. Furthermore, a high circadian clock-based risk score indicated shorter DFS (p < 0.0001), early progression (p < 0.0001), and higher 5-year death rate (p = 0.007) in PC. The risk score was related to tumor status (p < 0.001), lymph node status (p < 0.001), and ribosome-related biogenesis and pathways. Conclusions The vital roles of circadian clock genes in clinical outcomes were fully depicted. The circadian clock-based risk score model could reflect and predict the prognosis of patients with PC.

scholarly journals Transcriptomal dissection of soybean circadian rhythmicity in two geographically, phenotypically and genetically distinct cultivars

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Yanlei Yue ◽  
Ze Jiang ◽  
Enoch Sapey ◽  
Tingting Wu ◽  
Shi Sun ◽  
...  
Keyword(s):  
Gene Expression ◽  
Circadian Clock ◽  
Chromosome Structure ◽  
Clock Genes ◽  
Expression Profiles ◽  
Circadian Rhythmicity ◽  
Rna Seq ◽  
Night Time ◽  
Time Points ◽  
Circadian Clock Genes

Abstract Background In soybean, some circadian clock genes have been identified as loci for maturity traits. However, the effects of these genes on soybean circadian rhythmicity and their impacts on maturity are unclear. Results We used two geographically, phenotypically and genetically distinct cultivars, conventional juvenile Zhonghuang 24 (with functional J/GmELF3a, a homolog of the circadian clock indispensable component EARLY FLOWERING 3) and long juvenile Huaxia 3 (with dysfunctional j/Gmelf3a) to dissect the soybean circadian clock with time-series transcriptomal RNA-Seq analysis of unifoliate leaves on a day scale. The results showed that several known circadian clock components, including RVE1, GI, LUX and TOC1, phase differently in soybean than in Arabidopsis, demonstrating that the soybean circadian clock is obviously different from the canonical model in Arabidopsis. In contrast to the observation that ELF3 dysfunction results in clock arrhythmia in Arabidopsis, the circadian clock is conserved in soybean regardless of the functional status of J/GmELF3a. Soybean exhibits a circadian rhythmicity in both gene expression and alternative splicing. Genes can be grouped into six clusters, C1-C6, with different expression profiles. Many more genes are grouped into the night clusters (C4-C6) than in the day cluster (C2), showing that night is essential for gene expression and regulation. Moreover, soybean chromosomes are activated with a circadian rhythmicity, indicating that high-order chromosome structure might impact circadian rhythmicity. Interestingly, night time points were clustered in one group, while day time points were separated into two groups, morning and afternoon, demonstrating that morning and afternoon are representative of different environments for soybean growth and development. However, no genes were consistently differentially expressed over different time-points, indicating that it is necessary to perform a circadian rhythmicity analysis to more thoroughly dissect the function of a gene. Moreover, the analysis of the circadian rhythmicity of the GmFT family showed that GmELF3a might phase- and amplitude-modulate the GmFT family to regulate the juvenility and maturity traits of soybean. Conclusions These results and the resultant RNA-seq data should be helpful in understanding the soybean circadian clock and elucidating the connection between the circadian clock and soybean maturity.

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