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1.
J Mol Cell Cardiol ; 170: 75-86, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35714558

RESUMO

Long noncoding RNAs (lncRNAs) are critical regulators of inflammation with great potential as new therapeutic targets. However, the role of lncRNAs in early atherosclerosis remains poorly characterized. This study aimed to identify the key lncRNA players in activated endothelial cells (ECs). The lncRNAs in response to pro-inflammatory factors in ECs were screened through RNA sequencing. ICAM-1-related non-coding RNA (ICR) was identified as the most potential candidate for early atherosclerosis. ICR is essential for intercellular adhesion molecule-1 (ICAM1) expression, EC adhesion and migration. In a high fat diet-induced atherosclerosis model in mice, ICR is upregulated in the development of atherosclerosis. After intravenous injection of adenovirus carrying shRNA for mouse ICR, the atherosclerotic plaque area was markedly reduced with the declined expression of ICR and ICAM1. Mechanistically, ICR stabilized the mRNA of ICAM1 in quiescent ECs; while under inflammatory stress, ICR upregulated ICAM1 in a nuclear factor kappa B (NF-κB) dependent manner. RNA-seq analysis showed pro-inflammatory targets of NF-κB were regulated by ICR. Furthermore, the chromatin immunoprecipitation assays showed that p65 binds to ICR promoter and facilitates its transcription. Interestingly, ICR, in turn, promotes p65 accumulation and activity, forming a positive feedback loop to amplify NF-κB signaling. Preventing the degradation of p65 using proteasome inhibitors rescued the expression of NF-κB targets suppressed by ICR. Taken together, ICR acts as an accelerator to amplify NF-κB signaling in activated ECs and suppressing ICR is a promising early intervention for atherosclerosis through ICR/p65 loop blockade.


Assuntos
Aterosclerose , RNA Longo não Codificante , Animais , Aterosclerose/genética , Células Endoteliais/metabolismo , Molécula 1 de Adesão Intercelular/genética , Camundongos , NF-kappa B/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
2.
Nano Lett ; 21(8): 3680-3689, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33596656

RESUMO

Efficient endosomal escape is the most essential but challenging issue for siRNA drug development. Herein, a series of quaternary ammonium-based amphiphilic triblock polymers harnessing an elaborately tailored pH-sensitive hydrophobic core were synthesized and screened. Upon incubating in an endosomal pH environment (pH 6.5-6.8), mPEG45-P(DPA50-co-DMAEMA56)-PT53 (PDDT, the optimized polymer) nanomicelles (PDDT-Ms) and PDDT-Ms/siRNA polyplexes rapidly disassembled, leading to promoted cytosolic release of internalized siRNA and enhanced silencing activity evident from comprehensive analysis of the colocalization and gene silencing using a lysosomotropic agent (chloroquine) and an endosomal trafficking inhibitor (bafilomycin A1). In addition, PDDT-Ms/siPLK1 dramatically repressed tumor growth in both HepG2-xenograft and highly malignant patient-derived xenograft models. PDDT-Ms-armed siPD-L1 efficiently blocked the interaction of PD-L1 and PD-1 and restored immunological surveillance in CT-26-xenograft murine model. PDDT-Ms/siRNA exhibited ideal safety profiles in these assays. This study provides guidelines for rational design and optimization of block polymers for efficient endosomal escape of internalized siRNA and cancer therapy.


Assuntos
Endossomos , Polímeros , Animais , Linhagem Celular Tumoral , Inativação Gênica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , RNA Interferente Pequeno/genética
3.
Arch Biochem Biophys ; 711: 109023, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34480914

RESUMO

In eukaryotes, N6-methyladenosine (m6A) is one of the most abundant modifications on RNAs, and it plays important roles in many biological processes and diseases such as cancer. While most m6A researches focus on message RNAs and long non-coding RNAs, recent studies have reported the presence of m6A in small RNAs. Nevertheless, current knowledge about m6A prevalence in mature microRNAs (miRNA) is extremely limited and the functional significance of m6A methylation in miRNAs remains to be elucidated. Here, we demonstrated cell-specific m6A profiles of miRNAs in A549 human non-small cell lung cancer (NSCLC) cells and HEK293A cells by using miRNA m6A immunoprecipitation sequencing and constructed the consensus motif in m6A-enriched miRNAs de novo. We found that miR-21-5p, an oncogenic miRNA, showed the highest m6A enrichment in NSCLC cells. Depletion of the demethylase ALKBH5 did not change the expression level of miR-21-5p, but altered the m6A abundance of miR-21-5p, thereby changing the expression levels of its target gene. We further synthesized m6A modified miR-21-5p mimics in vitro and demonstrated that in NSCLC cells, m6A marks in mature miR-21-5p could directly affect its silencing potency towards target genes, which finally impaired its promotion to proliferation and motility. Together, our findings reveal the landscape of m6A modification in mature miRNAs, and provide the first evidence that it may contribute to the mRNA responses to cancer-related miRNAs.


Assuntos
Adenosina/análogos & derivados , MicroRNAs/metabolismo , Células A549 , Adenosina/análise , Adenosina/química , Adenosina/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Metilação , MicroRNAs/análise , MicroRNAs/química , Análise de Sequência de RNA
4.
Circ J ; 84(7): 1155-1162, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32404537

RESUMO

BACKGROUND: Circulating microRNAs (miRNA) are potential prognostic biomarkers for cardiovascular disease. We aimed to identify serum miRNA as an effective predictor for coronary artery disease (CAD) events in a general population cohort.Methods and Results:Serum miRNAs associated with CAD were determined by small RNA sequencing and quantitative RT-PCR. Further, the predictive ability of identified serum miRNAs was measured in a general population of 2,812 people. As a main outcome measure, CAD events were collected for 6 years and included acute myocardial infarction and subsequent myocardial infarction. Out of the 48 miRNA candidates, 5 miRNAs (miR-10a-5p, miR-126-3p, miR-210-3p, miR-423-3p and miR-92a-3p) showed better reliability and repeatability in serum. Then, the association of serum levels of the 5 miRNAs with CAD was validated. Furthermore, miR-10a-5p and miR-423-3p, which showed better performance, were tested in the large cohort, with a median follow up of 6.0 years. In multivariable Cox regression analysis, only miR-423-3p (P for trend<0.001) was able to precisely predict CAD events. Moreover, the addition of circulating miR-423-3p with the traditional risk factors together markedly improved the various model performance measures, including the area under the operating characteristics curve (0.782 vs. 0.806), Akaike Information Criterion (965.845 vs. 943.113) and net reclassification improvement (19.18%). CONCLUSIONS: Circulating miR-423-3p can improve the prediction of primary CAD outcomes on the basis of a traditional risk factor model in general population.


Assuntos
MicroRNA Circulante/sangue , Doença da Artéria Coronariana/diagnóstico , MicroRNAs/sangue , Adulto , Biomarcadores/sangue , China/epidemiologia , MicroRNA Circulante/genética , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Tempo
5.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491855

RESUMO

The DiGeorge syndrome critical region gene 8 (Dgcr8) knockout strategy has been widely used to study the function of canonical microRNAs (miRNAs) in vitro and in vivo. However, primary miRNA (pri-miRNA) transcripts are accumulated in Dgcr8 knockout cells due to interrupted processing. Whether abnormally accumulated pri-miRNAs have any function is unknown. Here, using clustered regularly interspaced short palindromic repeats system/CRISPR-associated protein 9 (CRISPR/Cas9), we successfully knocked out the primary microRNA-290~295 (pri-miR-290~295) cluster, the most highly expressed miRNA cluster in mouse embryonic stem cells (ESCs), in Dgcr8 knockout background. We found that the major defects associated with Dgcr8 knockout in mouse ESCs, including higher expression of epithelial-to-mesenchymal transition (EMT) markers, slower proliferation, G1 accumulation, and defects in silencing self-renewal, were not affected by the deletion of pri-miR-290~290 cluster. Interestingly, the transcription of neighboring gene nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 12(Nlrp12) was upregulated upon the deletion of the pri-miR-290~295 cluster. Together, our results suggested that the major defects in Dgcr8 knockout ESCs were not due to the accumulation of pri-miR-290~295, and the deletion of miRNA genes could affect the transcription of neighboring DNA elements.


Assuntos
MicroRNAs/genética , Células-Tronco Embrionárias Murinas/metabolismo , Interferência de RNA , Proteínas de Ligação a RNA/genética , Animais , Biomarcadores , Ciclo Celular/genética , Diferenciação Celular/genética , Proliferação de Células , Autorrenovação Celular/genética , Transição Epitelial-Mesenquimal , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Camundongos , Camundongos Knockout , Fenótipo
6.
Nucleic Acids Res ; 44(5): 2274-82, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26873922

RESUMO

RNA activation (RNAa) is the upregulation of gene expression by small activating RNAs (saRNAs). In order to investigate the mechanism by which saRNAs act in RNAa, we used the progesterone receptor (PR) gene as a model, established a panel of effective saRNAs and assessed the involvement of the sense and antisense strands of saRNA in RNAa. All active saRNAs had their antisense strand effectively incorporated into Ago2, whereas such consistency did not occur for the sense strand. Using a distal hotspot for saRNA targeting at 1.6-kb upstream from the PR transcription start site, we further established that gene activation mediated by saRNA depended on the complementarity of the 5' region of the antisense strand, and that such activity was largely abolished by mutations in this region of the saRNA. We found markedly reduced RNAa effects when we created mutations in the genomic target site of saRNA PR-1611, thus providing evidence that RNAa depends on the integrity of the DNA target. We further demonstrated that this saRNA bound the target site on promoter DNA. These results demonstrated that saRNAs work via an on-site mechanism by binding to target genomic DNA in a seed-region-dependent manner, reminiscent of miRNA-like target recognition.


Assuntos
Cromatina/química , DNA/genética , Regulação da Expressão Gênica , Pequeno RNA não Traduzido/genética , Receptores de Progesterona/genética , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Sistemas CRISPR-Cas , Cromatina/metabolismo , DNA/metabolismo , Genes Reporter , Células HEK293 , Humanos , Luciferases/genética , Luciferases/metabolismo , Células MCF-7 , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Pequeno RNA não Traduzido/metabolismo , Receptores de Progesterona/metabolismo , Sítio de Iniciação de Transcrição
7.
Adv Exp Med Biol ; 983: 41-51, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28639190

RESUMO

Small activating RNA (saRNA)-mediated gene activation has opened a new avenue for upregulating the expression of target genes by promoting endogenous transcription, a phenomenon known as RNA activation (RNAa). RNAa is distinct from the established RNAi mechanistic framework, although AGO2 is required by both. The precise mechanism of RNAa is currently disputable and has become a bottleneck in the development of this new technology. saRNA may achieve activation of target genes by directly binding to DNA targets in promoter, or interacting with antisense transcripts transcribed from overlapping promoter sequences, or by silencing other genes. In this chapter, we focused on recent development in our understanding of the target-recognition mechanism in RNAa. Conflicting results on saRNA targets are also discussed. Despite that the target mechanism of RNAa is more complex than expected and not completely understood so far, independent lines of evidence have suggested that saRNAs work by an "on-site" mechanism by binding to target genomic DNA in a "seed-region"-dependent manner. Finally, "off-target" effects of saRNA are observed and should be carefully controlled in designing experiments for and interpreting results from RNAa-related studies.


Assuntos
Interferência de RNA , RNA/genética , Ativação Transcricional , DNA , Regiões Promotoras Genéticas
8.
Nano Lett ; 16(11): 6916-6923, 2016 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-27748606

RESUMO

The extremely low efficient cytosolic release of the internalized siRNA has emerged recently as a central issue for siRNA delivery, while there is a lack of guidelines to facilitate the cytosolic release of internalized siRNA. To address these concerns, we studied the contribution of the pH-sensitive inner core on handling the cytosolic release of siRNA delivered by a series of PG-P(DPAx-co-DMAEMAy)-PCB amphiphilic polycation nanomicelles (GDDC-Ms) with extremely low internalization (<1/4 of lipofactamine 2000 (Lipo2000)). Significantly, just by varying the mole ratio of DPA and DMAEMA to adjust the initial disassembly pH (pHdis) of the core near to 6.8, GDDC4-Ms/siRNA could get nearly 98.8% silencing efficiency at w/w = 12 with 50 nM siRNA and ∼78% silencing efficiency at w/w = 30 with a very low dose of 5 nM siRNA in HepG-2 cell lines, while Lipo2000 only got 65.7% with 50 nM siRNA. Furthermore, ∼98.4% silencing efficiency was also realized in the hard-to-transfect human acute monoblastic leukemia cell line U937 by GDDC4-Ms/siRNA (at w/w = 15, 50 nM siRNA), in the inefficient case for Lipo2000. Additionally, the high silencing efficiency (∼80%) in skin tissue in vivo was discovered. Undoubtedly, the robust potential of GDDC4-Ms in handling the cytosolic release paves a simple but efficient new way for the design of the nonviral siRNA vector.

9.
Mol Biol Evol ; 32(12): 3143-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26341297

RESUMO

Although millions of RNA editing events have been reported to modify hereditary information across the primate transcriptome, evidence for their functional significance remains largely elusive, particularly for the vast majority of editing sites in noncoding regions. Here, we report a new mechanism for the functionality of RNA editing-a crosstalk with PIWI-interacting RNA (piRNA) biogenesis. Exploiting rhesus macaque as an emerging model organism closely related to human, in combination with extensive genome and transcriptome sequencing in seven tissues of the same animal, we deciphered accurate RNA editome across both long transcripts and the piRNA species. Superimposing and comparing these two distinct RNA editome profiles revealed 4,170 editing-bearing piRNA variants, or epiRNAs, that primarily derived from edited long transcripts. These epiRNAs represent distinct entities that evidence an intersection between RNA editing regulations and piRNA biogenesis. Population genetics analyses in a macaque population of 31 independent animals further demonstrated that the epiRNA-associated RNA editing is maintained by purifying selection, lending support to the functional significance of this crosstalk in rhesus macaque. Correspondingly, these findings are consistent in human, supporting the conservation of this mechanism during the primate evolution. Overall, our study reports the earliest lines of evidence for a crosstalk between selectively constrained RNA editing regulation and piRNA biogenesis, and further illustrates that such an interaction may contribute substantially to the diversification of the piRNA repertoire in primates.


Assuntos
Macaca mulatta/genética , Edição de RNA , RNA Interferente Pequeno/biossíntese , Análise de Sequência de RNA/métodos , Animais , Humanos , Macaca mulatta/metabolismo , Modelos Animais , RNA Interferente Pequeno/genética , Transcriptoma
10.
FASEB J ; 29(7): 3054-64, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25868726

RESUMO

Metastasis-associated lung adenocarcinoma transcript 1 (Malat1) is an example of a functional long noncoding RNA involved in many biologic processes. However, the mechanisms for Malat1 in myogenesis are unclear. Serum response factor (SRF) is a pivotal transcription factor for muscle proliferation and differentiation and is reported to be a target gene for muscle-specific microRNA-133 (miR-133). In this study, we initially found that silencing Malat1 in the mouse myoblast C2C12 cell line inhibited myocyte differentiation and decreased Srf at both the RNA and protein levels. Srf silencing decreased Malat1 expression as well. Further study revealed that Malat1 contained an miR-133 functional target site, and the interplay between Malat1 and Srf was miR-133 dependent. We demonstrated that Malat1 modulates Srf through miR-133 as a competing endogenous RNA and established a novel connection among Malat1, miR-133, and Srf in myoblast differentiation.


Assuntos
MicroRNAs/genética , MicroRNAs/metabolismo , Desenvolvimento Muscular/genética , Desenvolvimento Muscular/fisiologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fator de Resposta Sérica/genética , Fator de Resposta Sérica/metabolismo , Animais , Sequência de Bases , Sítios de Ligação/genética , Ligação Competitiva , Diferenciação Celular , Linhagem Celular , Inativação Gênica , Células HEK293 , Humanos , Camundongos , Modelos Biológicos , Mutação , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/metabolismo , RNA Longo não Codificante/antagonistas & inibidores
11.
RNA Biol ; 13(1): 98-108, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26618242

RESUMO

Antisense Noncoding RNA in the INK4 Locus (ANRIL) is the prime candidate gene at Chr9p21, the well-defined genetic risk locus associated with multiple human diseases including coronary artery disease (CAD), while little is known regarding its role in the pathological processes. Endothelial dysfunction triggers atherosclerotic processes that are causatively linked to CAD. To evaluate the function of ANRIL in human endothelial cells (ECs), we examined ANRIL expression under pathological stimuli and found ANRIL was markedly induced by pro-inflammatory factors. Loss-of-function and chromatin immunoprecipitation approaches revealed that NF-κB mediates TNF-α induced ANRIL expression. RNA sequencing revealed that ANRIL silencing dysregulated expression of inflammatory genes including IL6 and IL8 under TNF-α treatment. We explored the regulatory mechanism of ANRIL on IL6/8 and found that Yin Yang 1 (YY1), an ANRIL binding transcriptional factor revealed by RNA immunoprecipitation, was required for IL6/8 expression under TNF-α treatment. YY1 was enriched at promoter loci of IL6/8 and ANRIL silencing impaired the enrichment, indicating a cooperation between ANRIL and YY1 in the regulation of inflammatory genes. For the first time, we establish the connection between ANRIL and NF-κB pathway and show that ANRIL regulates inflammatory responses through binding with YY1. The newly identified TNF-α-NF-κB-ANRIL/YY1-IL6/8 pathway enhances understanding of the etiology of CAD and provides potential therapeutic target for treatment of CAD.


Assuntos
Células Endoteliais/imunologia , NF-kappa B/genética , RNA Longo não Codificante/genética , Fator de Necrose Tumoral alfa/farmacologia , Fator de Transcrição YY1/genética , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-6/genética , Interleucina-8/genética , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos
12.
Breast Cancer Res Treat ; 152(1): 199-208, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26033707

RESUMO

Long non-coding HOX transcript antisense intergenic RNA (HOTAIR) plays an important role in breast cancer. The purpose of this study was to determine whether circulating HOTAIR can be used for breast cancer diagnosis. HOTAIR in serum was measured by PCR-based direct detection. Reverse transcriptase and DNase I treatment were used to distinguish the DNA and RNA forms of HOTAIR. To determine whether circulating HOTAIR is a biomarker for breast cancer, the DNA of HOTAIR from breast cancer patients and healthy controls was measured at both the discovery stage (48 individuals) and an independent validation stage (156 individuals). The diagnostic accuracy was assessed by the receiver operating characteristic curve (ROC) and the area under the curve (AUC). We showed that the major form of HOTAIR-derived fragment in serum is DNA rather than RNA in our study, the same as for MALAT-1, another well-described lincRNA. A higher circulating DNA level of HOTAIR was found in patients at the discovery stage (P = 0.0008). ROC analysis revealed that the circulating HOTAIR DNA distinguished breast cancer patients from healthy individuals (AUC = 0.799). This finding was confirmed at the validation stage. Though circulating MALAT-1 DNA was altered in the discovery stage, it showed no significant difference in the validation stage. In the entire set of 204 samples, the circulating HOTAIR DNA showed a 2.15-fold change in patients compared with healthy controls (P < 0.0001, AUC = 0.786). The optimal cutoff value for diagnosis was 0.30 with sensitivity of 80.0 % and specificity of 68.3 %. Moreover, a correlation between the DNA level of circulating HOTAIR and the progress of breast cancer was established. We have demonstrated that the circulating DNA of HOTAIR is a potential biomarker for breast cancer.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Processamento Alternativo , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Longo não Codificante/sangue , Curva ROC
13.
Breast Cancer Res Treat ; 154(2): 423-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26476723

RESUMO

Novel, non-invasive biomarkers to diagnose breast cancer with high sensitivity and specificity are greatly desired. Circulating microRNAs (miRNAs) show potential for breast cancer detection, but the existing results appear to be mixed. Using microscale serum, we established a novel serum-direct multiplex detection assay based on RT-PCR (SdM-RT-PCR). Ninety-three miRNAs dysregulated or with functions in breast cancer were selected as candidates, and additional 3 miRNAs were chosen as endogenous controls. We first conducted miRNA profiling of these 96 miRNAs by SdM-RT-PCR using the sera of 25 breast cancer patients at diagnosis prior to treatment and 20 age-matched healthy controls. miRNAs showing significantly different expression levels between patients and controls were further analyzed using a logistic regression model. A miRNA signature was validated in an independent set of 128 serum samples composed of 76 breast cancer patients and 52 healthy controls. In the discovery stage, we identified 23 miRNAs as significantly dysregulated in breast cancer patients compared with healthy controls. Of these, 10 miRNAs were previously identified as dysregulated in breast cancer; 14 miRNAs remained significant after P-values were adjusted by both correction methods. Principal component analysis and hierarchical clustering of these miRNAs separated patients from controls. Furthermore, the 3-miRNA signature (miR-199a, miR-29c, and miR-424) with the highest diagnostic accuracy for distinguishing breast cancer patients from controls by ROC curve analysis (AUC = 0.888) was successfully confirmed in the validation set (AUC = 0.901). Our data demonstrate that the SdM-RT-PCR assay is an effective breast cancer profiling method that utilizes very small volumes and is compatible with Biobank. Furthermore, the identified 3-miRNA signature is a promising circulating biomarker for breast cancer diagnosis.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , MicroRNAs/genética , Adulto , Idoso , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Análise por Conglomerados , Detecção Precoce de Câncer , Feminino , Perfilação da Expressão Gênica , Humanos , MicroRNAs/sangue , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes
14.
RNA Biol ; 11(10): 1243-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25590615

RESUMO

MicroRNA knockout by genome editing technologies is promising. In order to extend the application of the technology and to investigate the function of a specific miRNA, we used CRISPR/Cas9 to deplete human miR-93 from a cluster by targeting its 5' region in HeLa cells. Various small indels were induced in the targeted region containing the Drosha processing site and seed sequences. Interestingly, we found that even a single nucleotide deletion led to complete knockout of the target miRNA with high specificity. Functional knockout was confirmed by phenotype analysis. Furthermore, de novo microRNAs were not found by RNA-seq. Nevertheless, expression of the pri-microRNAs was increased. When combined with structural analysis, the data indicated that biogenesis was impaired. Altogether, we showed that small indels in the 5' region of a microRNA result in sequence depletion as well as Drosha processing retard.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Mutação INDEL/genética , MicroRNAs/genética , Precursores de RNA/genética , Processamento Pós-Transcricional do RNA , Ribonuclease III/genética , Sequência de Bases , Western Blotting , Proliferação de Células , Células HeLa , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Precursores de RNA/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease III/metabolismo
15.
Sci China Life Sci ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38995489

RESUMO

Many long noncoding RNAs (lncRNAs) have been identified through siRNA-based screening as essential regulators of embryonic stem cell (ESC) pluripotency. However, the biological and molecular functions of most lncRNAs remain unclear. Here, we employed CRISPR/Cas9-mediated knockout technology to explore the functions of 8 lncRNAs previously reported to promote pluripotency in mouse ESCs. Unexpectedly, all of these lncRNAs were dispensable for pluripotency maintenance and proliferation in mouse ESCs when disrupted individually or in combination. Single-cell transcriptomic analysis also showed that the knockout of these lncRNAs has a minimal impact on pluripotency gene expression and cell identity. We further showed that several small hairpin RNAs (shRNAs) previously used to knock down lncRNAs caused the downregulation of pluripotency genes in the corresponding lncRNA-knockout ESCs, indicating that off-target effects likely responsible for the pluripotency defects caused by these shRNAs. Interestingly, linc1343-knockout and linc1343-knockdown ESCs failed to form cystic structures and exhibited high expression of pluripotency genes during embryoid body (EB) differentiation. By reintroducing RNA products generated from the linc1343 locus, we found that two snoRNAs, Snora73a and Snora73b, but not lncRNAs, could rescue pluripotency silencing defects during EB differentiation of linc1343 knockout ESCs. Our results suggest that the 8 previously annotated pluripotency-regulating lncRNAs have no overt functions in conventional ESC culture; however, we identified snoRNA products derived from an annotated lncRNA locus as essential regulators for silencing pluripotency genes.

16.
BMC Geriatr ; 13: 91, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24016068

RESUMO

BACKGROUND: Existing literature indicates that ADRB2 gene is associated with health and longevity, but none of previous studies investigated associations of carrying the ADRB2 minor alleles and interactions between ADRB2 genotypes and social/behavioral factors(GxE) with health outcomes at advanced ages. This study intends to fill in this research gap. METHOD: We conducted an exploratory analysis, using longitudinal survey phenotype/genotype data from 877 oldest-old aged 90+. To estimate association of GxE interactions with health outcome, adjusted for the potential correlation between genotypes and social/behavioral factors and various other potentially confounding factors, we develop and test an innovative three-step procedure which combines logistic regression and structural equation methods. RESULTS: Interaction between regular exercise and carrying rs1042718 minor allele is significantly and positively associated with good cognitive function; interaction between regular exercise and carrying rs1042718 or rs1042719 minor allele is significantly and positively associated with self-reported good health; and interaction between social-leisure activities and carrying rs1042719 minor allele is significantly and positively associated with self-reported good health. Carrying rs1042718 or rs1042719 minor alleles is significantly and negatively associated with negative emotion, but the ADRB2 SNPs are not significantly associated with cognitive function and self-reported health. Our structural equation analysis found that, adjusted for the confounding effects of correlation of the ADRB2 SNPs with negative emotion, interaction between negative emotion and carrying rs1042718 or rs1042719 minor allele is significantly and negatively associated with cognitive function. The positive association of regular exercise and social-leisure activities with cognitive function and self-reported health, and negative association of negative emotion with cognitive function, were much stronger among carriers of rs1042718 or rs1042719 alleles, compared to the non-carriers. CONCLUSIONS: The results indicate significant positive associations of interactions between social/behavioral factors and the ADRB2 genotypes with health outcomes of cognitive function and self-reported health, and negative associations of carrying rs1042718 or rs1042719 minor alleles with negative emotion, at advanced ages in China. Our findings are exploratory rather than causal conclusions. This study implies that near-future health promotion programs considering individuals' genetic profiles, with appropriate protection of privacy/confidentiality, would yield increased benefits and reduced costs to the programs and their participants.


Assuntos
Envelhecimento/genética , Povo Asiático/genética , Genótipo , Nível de Saúde , Receptores Adrenérgicos beta 2/genética , Comportamento Social , Idoso de 80 Anos ou mais , Povo Asiático/etnologia , China/etnologia , Feminino , Inquéritos Epidemiológicos/métodos , Humanos , Estudos Longitudinais , Masculino
17.
ACS Omega ; 7(25): 21643-21653, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35785330

RESUMO

This study investigates the slugging characteristics of the gas-liquid slug flow interface in horizontal pipes. Using air and water as the experimental media, an experimental system was established using double-parallel conductance probes in a pipe with an inner diameter of 5 cm. By capturing the transient development process of the gas-liquid interface, the slugging characteristics of the gas-liquid two-phase flow interface in different flow regions were revealed. The results show that the value of gas-phase superficial velocity has an important influence on the shape and development of the interface wave during the slugging process. When the gravity wave generated during the slugging process can propagate upstream, the slugging phenomenon is periodic, and when the gravity wave cannot propagate upstream, the slugging phenomenon is random. The experiment verified the correctness of the interface instability theory and the liquid slug stability theory, and clarified the definitions of h o and h s. In addition, the paper analyzed the influence of gas-liquid velocity on slugging distance, h o and h s, and liquid slug frequency.

18.
Cells ; 11(14)2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35883646

RESUMO

BACKGROUND: The high morbidity and mortality of calcific aortic valve disease (CAVD) represents an unmet clinical need to investigate the molecular mechanisms involved. Evidence suggests that long non-coding RNAs (lncRNAs) can act as competitive endogenous RNAs (ceRNAs) by binding to microRNAs and regulating target genes in cardiovascular diseases. Nevertheless, the role of lncRNAs related ceRNA regulation in CAVD remains unclear. METHODS: RNAseq data of human diseased aortic valves were downloaded from GEO data sets (GSE153555, GSE199718), and differentially expressed lncRNAs (DElncRNAs), mRNAs (DEmRNAs) between CAVD and non-calcific aortic valve tissues with limma R package. Gene Ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Set Enrichment analysis (GSEA) were performed with clusterProfiler and gesaplot2 R package. The pivotal microRNAs were predicted by three databases intersection including TargetScan, MiRwalk, miRDB according to the genes related to the crucial pathways. ENCORI was used to predict targeted lncRNAs of hub microRNAs. We constructed lncRNA-miRNA-mRNA ceRNA network with Cytoscape software. The lncRNAs in ceRNA network were verified by RT-qPCR in human 30 calcific and 20 noncalcified aortic valve tissues. RESULTS: In total, 1739 DEmRNAs and 266 DElncRNAs were identified in CAVD. GO, KEGG pathway, GSEA annotations suggested that most of these genes are enriched in extracellular matrix (ECM)-reporter interaction pathways. The ceRNA networks associated with ECM-reporter interaction are constructed and related lncRNAs including H19, SNHG3 and ZNF436-AS1 were significant upregulated in human calcific aortic valve tissues, which might be potential therapeutic targets for CAVD. CONCLUSIONS: In this study, we proposed a novel lncRNA-miRNA-mRNA ceRNA network related to ECM-reporter interaction pathways, which potentially regulates CAVD progression.


Assuntos
Estenose da Valva Aórtica , MicroRNAs , RNA Longo não Codificante , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Estenose da Valva Aórtica/genética , Calcinose , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
19.
Sci China Life Sci ; 65(10): 1985-1997, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35391627

RESUMO

The pluripotent state of embryonic stem cells (ESCs) is regulated by a sophisticated network of transcription factors. High expression of KLF17 has recently been identified as a hallmark of naive state of human ESCs (hESCs). However, the functional role of KLF17 in naive state is not clear. Here, by employing various gain and loss-of-function approaches, we demonstrate that KLF17 is essential for the maintenance of naive state and promotes the primed to naive state transition in hESCs. Mechanistically, we identify MAPK3 and ZIC2 as two direct targets repressed by KLF17. Overexpression of MAPK3 or ZIC2 partially blocks KLF17 from promoting the naive pluripotency. Furthermore, we find that human and mouse homologs of KLF17 retain conserved functions in promoting naive pluripotency of both species. Finally, we show that Klf17 may be essential for early embryo development in mouse. These findings demonstrate the important and conserved function of KLF17 in promoting naive pluripotency and reveal two essential transcriptional targets of KLF17 that underlie its function.


Assuntos
Células-Tronco Embrionárias Humanas , Animais , Diferenciação Celular/genética , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Front Plant Sci ; 13: 992755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36352884

RESUMO

Drought is the abiotic factor that adversely affects plant growth, development survival, and crop productivity, posing a substantial threat to sustainable agriculture worldwide, especially in warm and dry areas. However, the extent of damage depends upon the crop growth stage, severity and frequency of the stress. In general, the reproductive growth phase is more sensitive to stresses causing a substantial loss in crop productivity. Saccharum spontaneum (L.) is the most variable wild relative of sugarcane with potential for use in sugarcane crop improvement programs. In the present study addresses the transcriptomic analysis of drought stress imposed by polyethylene glycol-6000 (PED-6000; w/v- 25%) on the root tip tissues of S. spontaneum GX83-10. The analysis of microarrays of drought-stressed roots was performed at 0 (CK), 2 (T2), 4 (T4), 8 (T8) and 24 h (T24). The analyzed data were compared with the gene function annotations of four major databases, such as Nr, KOG/COG, Swiss-Prot, and KEGG, and a total of 62,988 single-gene information was obtained. The differently expressed genes of 56237 (T4), 59319 (T8), and 58583 (T24), among which CK obtained the most significant number of expressed genes (35920) as compared to T24, with a total of 53683 trend genes. Gene ontology (GO) and KEGG analysis were performed on the 6 important trends, and a total of 598 significant GO IDs and 42 significantly enriched metabolic pathways. Furthermore, these findings also aid in the selection of novel genes and promoters that can be used to potentially produce crop plants with enhanced stress resistance efficiency for sustainable agriculture.

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