Identification of a set of miRNAs differentially expressed in transiently TIA-depleted HeLa cells by genome-wide profiling
ABSTRACT: Background: T-cell intracellular antigen (TIA) proteins function as regulators of cell homeostasis. These proteins control gene expression globally at multiple levels in response to dynamic regulatory changes and environmental stresses. Herein we identified a micro(mi)RNA signature associated to transiently TIA-depleted HeLa cells and analyzed the potential role of miRNAs combining genome-wide analysis data on mRNA and miRNA profiles. Results: Using high-throughput miRNA expression profiling, transient depletion of TIA-proteins in HeLa cells was observed to promote significant and reproducible changes (>2-fold, FDR<0.0001) affecting to a pool of up-regulated miRNAs (miR-30b*, miR125a-3p, miR-193a-5p, miR-197_MM2, miR-203, miR-210, miR-371-5p, miR-373*, miR-483-5p, miR-492, miR-498, miR-503, miR-572, miR-586, miR-612, miR-615, miR-623, miR-625, miR-629, miR-638, miR-658, miR-663, miR-671, miR-769-3p and miR-744). Differential expression analysis of some miRNAs was validated by reverse transcription and real time PCR. By target prediction and combined analysis of the genome-wide expression profiles of the mRNAs and miRNAs identified in TIA-depleted HeLa cells, we detected concomitant connections between up-regulated miRNAs and putative and experimental targeted mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes database analyses suggest that targeted mRNAs are related with biological processes associated to the regulation of DNA-dependent transcription, signal transduction and multicellular organismal development as well as with the enrichment of pathways in cancer, focal adhesion, regulation of actin cytoskeleton and MAPK and Wnt signalling pathways, respectively. Conclusion: All this considered, these observations suggest that specific miRNAs could act as potential mediators of the epigenetic switch linking transcriptomic dynamics and cell phenotypes mediated by TIA proteins. The analysis includes two cell types. Three biological replicates were performed per cell type and they were compared by using three dual-channel microarray hybridizations.
Project description:Brain tumor neurospheres (BTCSs) are cancer cells with neural stem cell-like properties found in the fatal brain tumor glioblastoma multiforme (GBM). These cells account for less than 1% of total tumor cells, are poorly differentiated and are believed to be involved in tumor induction, progression, treatment resistance and relapse. Specific miRNAs play important roles in modulating the proliferation and differentiation of neural stem cells, therefore, we aimed to identify miRNAs controlling differentiation in GBM-BTSCs through high throughput screening miRNA array profiling. We compared the miRNA expression profiles at the neurosphere state and upon 4 and 14 days of differentiation by using LIMMA, finding 21 differentially expressed miRNAs : hsa-miR-103, hsa-miR-106a, hsa-miR-106b, hsa-miR-15b, hsa-miR-17, hsa-miR-19a, hsa-miR-20a, hsa-miR-25, hsa-miR-301a and hsa-miR-93 were found up-regulated upon differentiation, while hsa-miR-100, hsa-miR-1259, hsa-miR-21, hsa-miR-22, hsa-miR-221, hsa-miR-222, hsa-miR-23b, hsa-miR-27a, hsa-miR-27b, hsa-miR-29a and hsa-miR-29b were down-regulated. Expression of 11 of the 21 miRNAs was examined by qPCR and 7 of them were validated: hsa-miR-21, hsa-miR-29a, hsa-miR-29b, hsa-miR-221 and hsa-miR-222 increased their expression upon differentiation, while hsa-miR-93 and hsa-miR-106a were inhibited. Functional studies demonstrated that miR-21 over-expression induced the expression of glial and/or neuronal cell markers in the neurospheres, possibly due to SPRY1 targeting by miR-21 in these cells, while miR-221 and miR-222 inhibition at the differentiated state reduced the expression of those differentiation markers. On the other hand, miR-29a and miR-29b targeted MCL1 in the GBM neurospheres and increased apoptotic cell death. Five GBM cell lines at the neurosphere state or after 4 or 14 days of differentiation
Project description:Rationale: Currently, there are no blood-based biomarkers with clinical utility for acute ischemic stroke (IS). microRNAs (miRNAs) show promise as disease markers due to their cell-type specific expression patterns and stability in peripheral blood. Objective: To identify circulating miRNAs associated with acute IS, determine their temporal course up to 90 days post-stroke, and explore their utility as an early diagnostic marker. Methods and Results: We used RNA sequencing to study expression changes of circulating miRNAs in a discovery sample of 20 IS patients and 20 matched healthy control subjects (HCs). We further applied qRT-PCR in independent samples for validation (40 IS patients and 40 matched controls), replication (200 IS patients, 100 HCs), and in 72 patients with transient ischemic attacks (TIA). Sampling of patient plasma was done immediately upon hospital arrival. We identified, validated, and replicated three differentially expressed miRNAs, which were upregulated in IS patients compared to both HCs (miR-125a-5p [1.8-fold; P=1.5x10-6], miR-125b-5p [2.5-fold; P=5.6x10-6], and miR-143-3p [4.8-fold; P=7.8x10-9]) and TIA patients (miR-125a-5p: P=0.003, miR-125b-5p: P=0.003, miR-143-3p: P=0.005). Longitudinal analysis of expression levels up to 90 days after stroke revealed a normalization to control levels for miR-125b-5p and miR-143-3p starting at day two, while miR-125a-5p remained elevated. Levels of all three miRNAs depended on platelet numbers in a platelet spike-in experiment, but were unaffected by chemical hypoxia in N2a cells and in experimental stroke models. In a random forest classification, miR-125a-5p, miR-125b-5p and miR-143-3p differentiated between HCs and IS patients with an area under the curve (AUC) of 0.90 (sensitivity: 85.6%; specificity: 76.3%), which was superior to multimodal cranial computed tomography obtained for routine diagnostics (sensitivity: 72.5%) and previously reported biomarkers of acute IS (neuron specific enolase: AUC=0.69, interleukin 6: AUC=0.82). Conclusions: A set of circulating miRNAs (miR-125a-5p, miR-125b-5p, miR-143-3p) associates with acute IS and might have clinical utility as an early diagnostic marker. Overall design: Prospective three-step case-control-study with discovery, validation, and replication step to examine circulating microRNAs after human ischemic stroke
Project description:Liver is uniquely capable to repair itself after injury. Multiple molecular and biochemical processes initiated after partial hepatectomy, lead to proliferation of all cells within the liver. MicroRNAs (miRNAs) are a class of highly abundant non-coding RNA molecules that cause post-transcriptional gene repression and are involved in several biological processes including cell cycle regulation and differentiation. We examined the expression levels of miRNAs in liver tissue received from control mice (L0) and compared them with the corresponding levels in liver tissue 12 hours after liver regeneration induced by 2/3 partial hepatectomy (L12). MicroRNA expression was investigated using microRNA profiling. Further qPCR analysis was used for validation of the differentially expressed microRNAs at an early stage of liver regeneration, induced by 2/3 partial hepatectomy. TargetScan and Gene Ontology (GO) analysis was performed in order to identify the possible miRNA target genes and their ontology, respectively. A subset of miRNAs were found to be differentially expressed during liver regeneration. Mmu-miR-21 and mmu-miR-30b* showed the higher levels of up-regulation in liver tissue from the hepatectomized mice at the end of the experiment (L12) compared to the sham operated mice (L0). Mmu-miR-21 up-regulation was further confirmed by qPCR. In situ hybridization (ISH) revealed that mmu-miR-21 exhibited the higher levels of expression at 12 hours post hepatectomy. On the contrary, mmu-miR-34c*, mmu-miR-144, mmu-miR-207, mmu-miR-207, mmu-miR-451, mmu-miR-582-3p and mmu-miR-290-5p exhibited <0.5 down-regulation in liver tissue after partial hepatectomy in L12 vs. L0 mice. Microarrays and qPCR results were in good agreement (Pearson correlation = 0.881). Our results provide important information regarding how microRNAs are deferentially expressed in murine liver tissue before and after partial hepatectomy. The early up-regulation of mmu-miR-21 during the process of liver regeneration suggests a regulatory role in liver regeneration in vivo. Twenty male wild type mice C57BL6J (8 weeks old) fed a standard diet were used for the liver regeneration experiment. Mice were housed in the animal facility of the University of Patras Medical School in temperature-, light- and humidity-controlled rooms with a 12-h light/dark cycle. All animal procedures were approved by the institutional review board of the University of Patras Medical School and were in accordance with EC Directive 86/609/EEC. A 2/3 partial hepatectomy (PH) was performed on 10 mice according to a recently published standardized protocol whereby the median and left lobes of the liver were removed and another 10 sham operated mice were used as the control group. The liver was allowed to regenerate and mice were sacrificed 12 hours after operation. Liver samples were collected from the sham operated mice (L0) and the hepatectomized mice at the end of the experiment (L12).
Project description:Background: TrkB-T1 is a BDNF receptor lacking a tyrosine kinase domain that is highly expressed in astrocytes and regulates BDNF-evoked calcium transients. Previous studies indicate that downregulation of TrkB-T1 in frontal cortex may be involved in neurobiological processes underlying suicide. Methods: In a microarray screening study (N=8), we interrogated all known microRNA in the frontal cortex of suicide completers with low expression of TrkB-T1 and normal controls. These findings were validated and followed up in a larger sample of cases and controls (N=55) Functional analyses included microRNA silencing, microRNA overexpression and luciferase assays to investigate specificity and to validate interactions between differentially expressed microRNA and TrkB-T1 Results: microRNAs Hsa-miR-185* and Hsa-miR-491-3p were upregulated in suicide completers with low expression of TrkB.T1 (Pnominal: 9.10-5 and 1.8.10-4 respectively; FDR-corrected p=0.031). Bioinformatic analyses revealed five putative binding sites for the DiGeorge syndrome linked microRNA Hsa-miR-185*in the 3’UTR of TrkB-T1, but none for Hsa-miR-491-3P. The increase of Hsa-miR-185* in frontal cortex of suicide completers was validated then confirmed in a larger, randomly selected group of suicide completers, where an inverse correlation between Hsa-miR-185* and TrkB-T1 expression was observed ( R=-0.404; p=0.002). Silencing and overexpression studies performed in human cell lines confirmed the inverse relationship between hsa-mir-185* and trkB-T1 expression. Luciferase assays demonstrated that Hsa-miR-185* binds to sequences in the 3’UTR of TrkB-T1. Conclusion: These results suggest that an increase of Hsa-miR-185* expression levels regulates, at least in part, the TrkB-T1 decrease observed in the frontal cortex of suicide completers and further implicate the 3MB 22q11 region in psychopathology. The microarray analysis consists in to compare the microRNA profile of four suicide completers with low TrkB-T1 expression level and four controls. Each RNA extract was labeled with Hy3 and hybridyzed with a reference sample labeled with Hy5. The reference sample was a pool of the eight RNA samples
Project description:This SuperSeries is composed of the following subset Series: GSE26393: Expression data of P4 stage hair follicle early bulge and non-bulge ORS cells GSE26394: Gene Expression data of P4 stage hair follicle ORS cells from DTG (K14-rtTA,TRE-miR-125b) and control littermates GSE26395: miRNA Expression data of P4 stage hair follicle ORS cells from DTG (K14-rtTA,TRE-miR-125b) and control littermates Refer to individual Series
Project description:In order to determine the serum microRNAs profile from middle-old aged patients with acute ischemic stroke and investigate possible diagnostic value of these differential microRNAs.The blood samples of 117 IS patients and 82 healthy people were collected. Differential miRNAs in serum from IS and control were screened with miRNA microarray analysis, and the expression of selected miRNAs were validated by quantitative reverse-transcriptase polymerase chain reaction assays (qRT-PCR). Results: We discovered 115 differentially expressed miRNAs, among which miR-32-3p, miR-106-5p, miR-532-5p were found be related to IS for the first time. Conclusions: In the present study, we identified the changed expression pattern of miRNAs in IS. Serum miR-32-3p, miR-106-5p, miR-1246 and miR-532-5p may serve as potential diagnostic biomarkers for IS. During the initial screening stage, we divided the serum samples into five groups (10 serum samples were pooled to form a group). Group A1: A denotes thrombotic stroke and 1 denotes hepertension. Group A14: A denotes thrombotic stroke, 1 denotes hepertension and 4 denotes hyperlipidemia. Group B2: B denotes embolic stroke and 2 denotes heart disease. Group B12: B denotes embolic stroke, 1 denotes hepertension and 2 denotes heart disease. Group 0: healthy control group.
Project description:Identifying the interaction partners of non-coding RNAs is essential for elucidating their functions. We have developed an approach, termed microRNA-cross-linking and immunoprecipitation (miR-CLIP), using pre-miRNAs modified with psoralen and biotin to capture their targets in cells. Photo-cross-linking and Argonaute 2-immunopurification followed by streptavidin affinity-purification of probe-linked RNAs provided selectivity in the capture of targets, identified by deep-sequencing. MiR-CLIP with pre-miR-106a, a miR-17-5p family member, identified hundreds of putative targets in HeLa cells, many carrying conserved sequences complementary to the miRNA seed but also many that were not predicted computationally. MiR-106a overexpression experiments confirmed that miR-CLIP captured functional targets, including H19, a long-non-coding RNA that is expressed during skeletal muscle cell differentiation. We showed that miR-17-5p family members bind H19 in HeLa cells and myoblasts. During myoblast differentiation levels of H19, miR-17-5p family members and mRNA targets changed in a manner suggesting that H19 acts as a sponge for these miRNAs. Two replicates of two cDNA libraries were submitted to deep sequencing: a sample from siH19-transfected cells and a control sample.
Project description:Adult aging is a complex biological process associated with altered gene expression and a decline in physiological performance. The microRNAs have been implicated in cardiac development, cardiac hypertrophy and heart failure. However, the impact of adult aging on cardiac expression of both miRNA guide strand (miR) and passenger strand (miR*), as well as miRNA clusters have not been well established. We explored the expression profile of both miR and miR* in the heart. We found that 65 miRNAs were differentially expressed in old versus young adult heart; approximately half of them were clustered miRNAs that were distributed in 11 miRNA clusters. Each miRNA cluster contains from 2 to as many as 71 miRNA genes. The majority of the clusters displayed unified expression, with most cluster members within a cluster being either increased or decreased together, suggesting that most clusters are regulated by a common signaling mechanism and that the combined expression of multiple miRNA genes in a cluster could pose an impact on a broad range of targets during aging. We also found age-related changes in the expression of miR*s. Bioinformatic analysis revealed that miR-21 and miR-21* had their own silencing targets. The expression of both miR and miR* correlated with that of pri-miRNA transcript over the time course from development and maturation through adult aging. Age-related changes in the expression of Ago1 and Ago2 proteins in the heart were also observed. Our data suggest that a concert of effects, including transcriptional regulation of pri-miRNA transcript and altered expression of Argonaut proteins, contribute to age-related changes in the expression of both miR and miR* strands during adult aging. The major changes occurred later in life, from middle to old age. It is likely that the expression of both miR and miR* is regulated by transcription and Ago1 and Ago2 proteins. Six healthy C57BL/6 mice were used in this study. Three of them were 4 months old (young adult mice: YA), and the other three were 24 months old (old mice). Total RNA samples were isolated from mouse hearts and then shipped to Exiqon Inc., where microRNA array analysis was performed. Three array slides were used for the hybridization. Each array slide hybridized with two samples labeld with either Hy3 or Hy5, with array #1 being hybridized with samples YA-1 (Hy3) and Old-1 (Hy5), array #2 with samples YA-2 (Hy3) and Old-2 (Hy5) and array #3 with samples YA-3 (Hy5) and Old-3 (Hy3). In our publication, we reveal the detail of the experiment and statistical analysis that were provided by Exiqon Inc.
Project description:Pterygium is a relatively common human ocular surface fibroproliferative disease that affects vision. Endogenously produced microRNA (miRNA) regulates gene expression in various ocular surface diseases and possibly pterygium. We aimed to investigate the role of miRNA in pterygium. Paired human pterygium and conjunctival tissues were obtained from patients diagnosed with primary pterygium. miRNA microarray profiling identified statistically significant miRNA changes which were matched to reciprocal significant changes in their target transcripts. We employed quantitative real-time polymerase chain reaction and found that hsa-miR-766 was up-regulated (2.57-fold) whilst hsa-miR-215 was down-regulated (0.49-fold) in pterygium compared to conjunctival control. Localization of miRNA was performed using in-situ hybridization. Transcript levels of predicted hsa-miR-766 targets, nuclear receptor subfamily 4, group A, member 1 and epidermal growth factor-containing fibulin-like extracellular matrix protein 1, were down-regulated in pterygium compared to conjunctiva by 0.53- and 0.64-fold, respectively. Collagens type 3, alpha 1 and type 4, alpha 2, both targets of hsa-miR-215, were up-regulated in pterygium by 3.01- and 3.11-fold, respectively. These changes were confirmed in the protein levels using immunofluorescent staining. Derangement of hsa-miR-766 and hsa-miR-215 may cause dysregulation of matrix rearrangement, cell proliferation and adhesion proteins, resulting in pterygium formation. Targeting miRNA may be a possible therapeutic approach in this disease. 3 pterygium samples and 3 matched conjuctiva samples from patients diagnosed with primary pterygium. A pool of all 6 samples was used as the common reference.
Project description:Identifying the interaction partners of non-coding RNAs is essential for elucidating their functions. We have developed an approach, termed microRNA-cross-linking and immunoprecipitation (miR-CLIP), using pre-miRNAs modified with psoralen and biotin to capture their targets in cells. Photo-cross-linking and Argonaute 2-immunopurification followed by streptavidin affinity-purification of probe-linked RNAs provided selectivity in the capture of targets, identified by deep-sequencing. MiR-CLIP with pre-miR-106a, a miR-17-5p family member, identified hundreds of putative targets in HeLa cells, many carrying conserved sequences complementary to the miRNA seed but also many that were not predicted computationally. MiR-106a overexpression experiments confirmed that miR-CLIP captured functional targets, including H19, a long-non-coding RNA that is expressed during skeletal muscle cell differentiation. We showed that miR-17-5p family members bind H19 in HeLa cells and myoblasts. During myoblast differentiation levels of H19, miR-17-5p family members and mRNA targets changed in a manner suggesting that H19 acts as a sponge for these miRNAs. Two replicates of three cDNA libraries were submitted to deep sequencing: a sample from RNA-7-transfected cells; a sample from pre-miR-106a transfected cells; and a control sample.