scholarly journals MicroRNA-143 Regulates Adipocyte Differentiation

2004 ◽  
Vol 279 (50) ◽  
pp. 52361-52365 ◽  
Author(s):  
Christine Esau ◽  
Xiaolin Kang ◽  
Eigen Peralta ◽  
Elaine Hanson ◽  
Eric G. Marcusson ◽  
...  

MicroRNAs (miRNAs) are endogenously expressed 20-24 nucleotide RNAs thought to repress protein translation through binding to a target mRNA (1-3). Only a few of the more than 250 predicted human miRNAs have been assigned any biological function. In an effort to uncover miRNAs important during adipocyte differentiation, antisense oligonucleotides (ASOs) targeting 86 human miRNAs were transfected into cultured human pre-adipocytes, and their ability to modulate adipocyte differentiation was evaluated. Expression of 254 miRNAs in differentiating adipocytes was also examined on a miRNA microarray. Here we report that the combination of expression data and functional assay results identified a role for miR-143 in adipocyte differentiation. miR-143 levels increased in differentiating adipocytes, and inhibition of miR-143 effectively inhibited adipocyte differentiation. In addition, protein levels of the proposed miR-143 target ERK5 (4) were higher in ASO-treated adipocytes. These results demonstrate that miR-143 is involved in adipocyte differentiation and may act through target gene ERK5.

2021 ◽  
Vol 11 ◽  
Author(s):  
Jie Jiang ◽  
Chong Liu ◽  
Guoyong Xu ◽  
Tuo Liang ◽  
Chaojie Yu ◽  
...  

IntroductionThis study aimed to identify important genes associated with melanoma to further develop new target gene therapies and analyze their significance concerning prognosis.Materials and methodsGene expression data for melanoma and normal tissue were downloaded from three databases. Differentially co-expressed genes were identified by WGCNA and DEGs analysis. These genes were subjected to GO, and KEGG enrichment analysis and construction of the PPI visualized with Cytoscape and screened for the top 10 Hub genes using CytoHubba. We validated the Hub gene’s protein levels with an immunohistochemical assay to confirm the accuracy of our analysis.ResultsA total of 435 differentially co-expressed genes were obtained. Survival curves showed that high expression of FOXM1,\ EXO1, KIF20A, TPX2, and CDC20 in melanoma patients with 5 of the top 10 hub genes was associated with reduced overall survival (OS). Immunohistochemistry showed that all five genes were expressed at higher protein levels in melanoma than in paracancerous tissues.ConclusionFOXM1, EXO1, KIF20A, TPX2, and CDC20 are prognosis-associated core genes of melanoma, and their high expression correlates with the low prognosis of melanoma patients and can be used as biomarkers for melanoma diagnosis, treatment, and prognosis prediction.


2020 ◽  
Author(s):  
Jie Jiang ◽  
Guoyong Xu ◽  
Tuo Liang ◽  
Chaojie Yu ◽  
Shian Liao ◽  
...  

Abstract Introduction: This study aimed to identify important genes associated with melanoma to further develop new target gene therapies and analyze their significance concerning prognosis.Materials and methods: Gene expression data for melanoma and normal tissue were downloaded from three databases. Differentially co-expressed genes were identified by WGCNA and DEGs analysis. These genes were subjected to GO, and KEGG enrichment analysis and construction of the PPI visualized with Cytoscape and screened for the top 10 Hub genes using CytoHubba. We validated the Hub gene's protein levels with an immunohistochemical assay to confirm the accuracy of our analysis.Results: A total of 435 differentially co-expressed genes were obtained. Survival curves showed that high expression of FOXM1, EXO1, KIF20A, TPX2, and CDC20 in melanoma patients with 5 of the top 10 hub genes was associated with reduced overall survival (OS). Immunohistochemistry showed that all five genes were expressed at higher protein levels in melanoma than in paracancerous tissues.Conclusion: FOXM1, EXO1, KIF20A, TPX2, and CDC20 are prognosis-associated core genes of melanoma, and their high expression correlates with the low prognosis of melanoma patients and can be used as biomarkers for melanoma diagnosis, treatment, and prognosis prediction.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1425
Author(s):  
Alena Shmakova ◽  
Mark Frost ◽  
Michael Batie ◽  
Niall S. Kenneth ◽  
Sonia Rocha

PBRM1, a component of the chromatin remodeller SWI/SNF, is often deleted or mutated in human cancers, most prominently in renal cancers. Core components of the SWI/SNF complex have been shown to be important for the cellular response to hypoxia. Here, we investigated how PBRM1 controls HIF-1α activity. We found that PBRM1 is required for HIF-1α transcriptional activity and protein levels. Mechanistically, PBRM1 is important for HIF-1α mRNA translation, as absence of PBRM1 results in reduced actively translating HIF-1α mRNA. Interestingly, we found that PBRM1, but not BRG1, interacts with the m6A reader protein YTHDF2. HIF-1α mRNA is m6A-modified, bound by PBRM1 and YTHDF2. PBRM1 is necessary for YTHDF2 binding to HIF-1α mRNA and reduction of YTHDF2 results in reduced HIF-1α protein expression in cells. Our results identify a SWI/SNF-independent function for PBRM1, interacting with HIF-1α mRNA and the epitranscriptome machinery. Furthermore, our results suggest that the epitranscriptome-associated proteins play a role in the control of hypoxia signalling pathways.


Genetics ◽  
2000 ◽  
Vol 156 (2) ◽  
pp. 763-774 ◽  
Author(s):  
Willis Li ◽  
Elizabeth Noll ◽  
Norbert Perrimon

Abstract Raf is an essential downstream effector of activated p21Ras (Ras) in transducing proliferation or differentiation signals. Following binding to Ras, Raf is translocated to the plasma membrane, where it is activated by a yet unidentified “Raf activator.” In an attempt to identify the Raf activator or additional molecules involved in the Raf signaling pathway, we conducted a genetic screen to identify genomic regions that are required for the biological function of Drosophila Raf (Draf). We tested a collection of chromosomal deficiencies representing ∼70% of the autosomal euchromatic genomic regions for their abilities to enhance the lethality associated with a hypomorphic viable allele of Draf, DrafSu2. Of the 148 autosomal deficiencies tested, 23 behaved as dominant enhancers of Draf  Su2, causing lethality in Draf  Su2 hemizygous males. Four of these deficiencies identified genes known to be involved in the Drosophila Ras/Raf (Ras1/Draf) pathway: Ras1, rolled (rl, encoding a MAPK), 14-3-3ϵ, and bowel (bowl). Two additional deficiencies removed the Drosophila Tec and Src homologs, Tec29A and Src64B. We demonstrate that Src64B interacts genetically with Draf and that an activated form of Src64B, when overexpressed in early embryos, causes ectopic expression of the Torso (Tor) receptor tyrosine kinase-target gene tailless. In addition, we show that a mutation in Tec29A partially suppresses a gain-of-function mutation in tor. These results suggest that Tec29A and Src64B are involved in Tor signaling, raising the possibility that they function to activate Draf. Finally, we discovered a genetic interaction between Draf  Su2 and Df(3L)vin5 that revealed a novel role of Draf in limb development. We find that loss of Draf activity causes limb defects, including pattern duplications, consistent with a role for Draf in regulation of engrailed (en) expression in imaginal discs.


2015 ◽  
Vol 35 (8) ◽  
pp. 1390-1400 ◽  
Author(s):  
Nancy Yu ◽  
Michael Kakunda ◽  
Victoria Pham ◽  
Jennie R. Lill ◽  
Pan Du ◽  
...  

The Wnt/β-catenin pathway causes accumulation of β-catenin in the cytoplasm and its subsequent translocation into the nucleus to initiate the transcription of the target genes. Without Wnt stimulation, β-catenin forms a complex with axin (axis inhibitor), adenomatous polyposis coli (APC), casein kinase 1α (CK1α), and glycogen synthase kinase 3β (GSK3β) and undergoes phosphorylation-dependent ubiquitination. Phosphatases, such as protein phosphatase 2A (PP2A), interestingly, also are components of this degradation complex; therefore, a balance must be reached between phosphorylation and dephosphorylation. How this balance is regulated is largely unknown. Here we show that a heat shock protein, HSP105, is a previously unidentified component of the β-catenin degradation complex. HSP105 is required for Wnt signaling, since depletion of HSP105 compromises β-catenin accumulation and target gene transcription upon Wnt stimulation. Mechanistically, HSP105 depletion disrupts the integration of PP2A into the β-catenin degradation complex, favoring the hyperphosphorylation and degradation of β-catenin. HSP105 is overexpressed in many types of tumors, correlating with increased nuclear β-catenin protein levels and Wnt target gene upregulation. Furthermore, overexpression of HSP105 is a prognostic biomarker that correlates with poor overall survival in breast cancer patients as well as melanoma patients participating in the BRIM2 clinical study.


2006 ◽  
Vol 25 (4-6) ◽  
pp. 503-521 ◽  
Author(s):  
Koji Morita ◽  
Koji Yamate ◽  
Shin-ichi Kurakata ◽  
Koji Abe ◽  
Kenji Watanabe ◽  
...  

2017 ◽  
Vol 45 (16) ◽  
pp. 9528-9546 ◽  
Author(s):  
Xue-hai Liang ◽  
Hong Sun ◽  
Wen Shen ◽  
Shiyu Wang ◽  
Joyee Yao ◽  
...  

Blood ◽  
2019 ◽  
Vol 133 (8) ◽  
pp. 830-839 ◽  
Author(s):  
Viola Close ◽  
William Close ◽  
Sabrina Julia Kugler ◽  
Michaela Reichenzeller ◽  
Deyan Yordanov Yosifov ◽  
...  

Abstract NOTCH1 is mutated in 10% of chronic lymphocytic leukemia (CLL) patients and is associated with poor outcome. However, NOTCH1 activation is identified in approximately one-half of CLL cases even in the absence of NOTCH1 mutations. Hence, there appear to be additional factors responsible for the impairment of NOTCH1 degradation. E3-ubiquitin ligase F-box and WD40 repeat domain containing-7 (FBXW7), a negative regulator of NOTCH1, is mutated in 2% to 6% of CLL patients. The functional consequences of these mutations in CLL are unknown. We found heterozygous FBXW7 mutations in 36 of 905 (4%) untreated CLL patients. The majority were missense mutations (78%) that mostly affected the WD40 substrate binding domain; 10% of mutations occurred in the first exon of the α-isoform. To identify target proteins of FBXW7 in CLL, we truncated the WD40 domain in CLL cell line HG-3 via clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein-9 (Cas9). Homozygous truncation of FBXW7 resulted in an increase of activated NOTCH1 intracellular domain (NICD) and c-MYC protein levels as well as elevated hypoxia-inducible factor 1-α activity. In silico modeling predicted that novel mutations G423V and W425C in the FBXW7-WD40 domain change the binding of protein substrates. This differential binding was confirmed via coimmunoprecipitation of overexpressed FBXW7 and NOTCH1. In primary CLL cells harboring FBXW7 mutations, activated NICD levels were increased and remained stable upon translation inhibition. FBXW7 mutations coincided with an increase in NOTCH1 target gene expression and explain a proportion of patients characterized by dysregulated NOTCH1 signaling.


2018 ◽  
Vol 59 (6) ◽  
pp. 982-993 ◽  
Author(s):  
Romeo Papazyan ◽  
Xueqing Liu ◽  
Jingwen Liu ◽  
Bin Dong ◽  
Emily M. Plummer ◽  
...  

Obeticholic acid (OCA) is a selective farnesoid X receptor (FXR) agonist that regulates bile acid and lipid metabolism. FXR activation induces distinct changes in circulating cholesterol among animal models and humans. The mechanistic basis of these effects has been elusive because of difficulties in studying lipoprotein homeostasis in mice, which predominantly package circulating cholesterol in HDLs. Here, we tested the effects of OCA in chimeric mice whose livers are mostly composed (≥80%) of human hepatocytes. Chimeric mice exhibited a human-like ratio of serum LDL cholesterol (LDL-C) to HDL cholesterol (HDL-C) at baseline. OCA treatment in chimeric mice increased circulating LDL-C and decreased circulating HDL-C levels, demonstrating that these mice closely model the cholesterol effects of FXR activation in humans. Mechanistically, OCA treatment increased hepatic cholesterol in chimeric mice but not in control mice. This increase correlated with decreased SREBP-2 activity and target gene expression, including a significant reduction in LDL receptor protein. Cotreatment with atorvastatin reduced total cholesterol, rescued LDL receptor protein levels, and normalized serum LDL-C. Treatment with two clinically relevant nonsteroidal FXR agonists elicited similar lipoprotein and hepatic changes in chimeric mice, suggesting that the increase in circulating LDL-C is a class effect of FXR activation.


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