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Objective. Angiogenesis is one of the therapeutic targets of cerebral infarction. Long noncoding RNAs (lncRNAs) can regulate the pathological process of angiogenesis following ischemic stroke. Taurine-upregulated gene 1 (TUG1), an lncRNA, is correlated to ischemic stroke. We intended to determine the effect of TUG1 on angiogenesis following an ischemic stroke. Materials and Methods. Middle cerebral artery occlusion (MCAO) was adopted to build a focal ischemic model of the rat brain, and pcDNA-TUG1 and miR-26a mimics were injected into rats. Neurological function was estimated through modified neurological severity scores. The volume of focal brain infarction was calculated through 2,3,5-triphenyltetrazolium chloride staining. The level of TUG1 and miR-26a was measured by PCR. The expression of vascular endothelial growth factor (VEGF) and CD31 was checked using immunohistochemistry and western blot. The correlation between miR-26a and TUG1 was verified through a luciferase reporter assay. Results. TUG1 increased noticeably while miR-26a was markedly reduced in MCAO rats. Overexpression of miR-26a improved neurological function recovery and enhanced cerebral angiogenesis in MCAO rats. TUG1 overexpression aggravated neurological deficits and suppressed cerebral angiogenesis in MCAO rats. Bioinformatics analysis revealed that miR-26a was one of the predicted targets of TUG1. Furthermore, TUG1 combined with miR-26a to regulate angiogenesis. TUG1 overexpression antagonized the role of miR-26a in neurological recovery and angiogenesis in MCAO rats. Conclusions. TUG1/miR-26a, which may act as a regulatory axis in angiogenesis following ischemic stroke, can be considered a potential target for cerebral infarction therapy. [ABSTRACT FROM AUTHOR]

The mechanism of miRNA-mediated root growth and development in response to nutrient deficiency in peanut (Arachis hypogaea L.) is still unclear. In the present study, we found that both nitrogen (N) and potassium (K) deficiency resulted in a significant reduction in plant growth, as indicated by the significantly decreased dry weight of both shoot and root tissues under N or K deficiency. Both N and K deficiency significantly reduced the root length, root surface area, root volume, root vitality, and weakened root respiration, as indicated by the reduced O2 consuming rate. N deficiency significantly decreased primary root length and lateral root number, which might be associated with the upregulation of miR160, miR167, miR393, and miR396, and the downregulation of AFB3 and GRF. The primary and lateral root responses to K deficiency were opposite to that of the N deficiency condition. The upregulated miR156, miR390, NAC4, ARF2, and AFB3, and the downregulated miR160, miR164, miR393, and SPL10 may have contributed to the growth of primary roots and lateral roots under K deficiency. Overall, roots responded differently to the N or K deficiency stresses in peanuts, potentially due to the miRNA-mediated pathway and mechanism. [ABSTRACT FROM AUTHOR]

Myocardial fibrosis (MF) can cause heart remodeling and it is an independent risk factor for malignant arrhythmias, sudden cardiac death, and other malignant cardiovascular events. It is often characterized by myocardial interstitial collagen deposition and hyperproliferation of cardiac fibroblasts (CFs). The transforming growth factor-β1 (TGF-β1) is the most influential profibrogenic factor. Resveratrol (RSV) is an active polyphenol substance that inhibits myocardial fibrosis. The mechanism of RSV-mediated inhibition of the proliferation of CFs at the microRNA level is not fully understood. We used TGF-β1 to induce CFs proliferation to simulate the pathogenesis of myocardial fibrosis. Neonatal rat CFs were treated with TGF-β1 in the presence or absence of resveratrol. Cell proliferation was measured using the CCK-8 and EdU assay. Collagen secretion was measured using hydroxyproline kit. Further, qPCR analysis was performed to determine microRNA levels after TGF-β1 or resveratrol treatment. To identify the target gene for miR-17, miR-17 was overexpressed or silenced, and the mRNA and protein levels of Smad7 were assessed. The effects of miR-17 silencing or Smad7 overexpression on cell proliferation and collagen secretion were also examined. Resveratrol treatment significantly decreased the TGF-β1-induced CF proliferation and collagen secretion. Resveratrol also decreased the levels of miR-17, miR-34a, and miR-181a in TGF-β1-treated CFs. Overexpression of miR-17 decreased the Smad7 mRNA and protein levels while silencing miR-17 increased them. Additionally, silencing miR-17 or overexpressing Smad7 decreased the TGF-β1-induced CFs proliferation and collagen secretion. In conclusion, resveratrol inhibits TGF-β1-induced CFs proliferation and collagen secretion. This inhibitory effect of resveratrol is orchestrated by the downregulation of miR-17 and the regulation of Smad7. [ABSTRACT FROM AUTHOR]

Background: Since miRNAs can play important roles in different cancer types, how to discover cancer related miRNAs is an important issue. In general, the miRNAs with differential expression is the focus of attention. However, some important cancer related miRNAs are not excavated by differential expression analysis. We take this type of miRNAs as 'dark matters' (DM-miRNA). It is our great interests to develop an algorithm to discover DM-miRNAs. Results: An effective method was developed to find DM-miRNAs. This method is mainly for mining potential DM-miRNAs by building basic miRNA-mRNA network (BMMN) and miRNA-lncRNA network (BMLN). The results indicate that miRNA-mRNA and miRNA-lncRNA interactions can be used as novel cancer biomarkers. Conclusions: The BMMN and BMLN can excavate the non-differentially expressed miRNAs which play an important role in the cancer. What's more, the edge biomarkers (miRNA-mRNA and miRNA-lncRNA interactions) contain more information than the node biomarkers. It will contribute to developing novel therapeutic candidates in cancers. [ABSTRACT FROM AUTHOR]

Mounting evidence has shown that miRNA expression is abnormal in various human cancers. Here, we mainly explored the biological function and the potential mechanisms of miR-1256 in non-small cell lung cancer (NSCLC). The miR-1256 mRNA expression was detected by quantitative real-time PCR and tectonic family member 1 (TCTN1) mRNA expression was detected by immunoblotting. The TCTN1 was identified to be the direct and specific target gene of miR-1256 by luciferase reporter assay. Cell proliferation was examined by methyl thiazolyl tetrazolium assay and migration was detected by transwell assay. MiR-1256 expression was downregulated in NSCLC tissues, whereas the expression of TCTN1 was upregulated, compared with normal tissues. We also found that overexpression of miR-1256 in these NSCLC cell lines inhibited cell proliferation and migration. Furthermore, TCTN1 was identified as a direct target of miR-1256 by luciferase reporter assays. Collectively, these data stated that the inhibitory effect of miR-1256 in NSCLC was realized by upregulating TCTN1, suggesting that miR-1256/TCTN1 axis may play a critical role as NSCLC therapeutic target. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRNAs) are endogenously encoded small RNAs that post-transcriptionally regulate gene expression and play essential roles in numerous developmental and physiological processes. Currently, little information on the transcriptome and tissue-specific expression of miRNAs is available in the model non-edible oilseed crop castor bean (Ricinus communis L.), one of the most important non-edible oilseed crops cultivated worldwide. Recent advances in sequencing technologies have allowed the identification of conserved and novel miRNAs in many plant species. Here, we used high-throughput sequencing technologies to identify and characterize the miRNAs in castor bean. Results: Five small RNA libraries were constructed for deep sequencing from root tips, leaves, developing seeds (at the initial stage, seed1; and at the fast oil accumulation stage, seed2) and endosperms in castor bean. High-throughput sequencing generated a large number of sequence reads of small RNAs in this study. In total, 86 conserved miRNAs were identified, including 63 known and 23 newly identified. Sixteen miRNA isoform variants in length were found from the conserved miRNAs of castor bean. MiRNAs displayed diverse organ-specific expression levels among five libraries. Combined with criteria for miRNA annotation and a RT-PCR approach, 72 novel miRNAs and their potential precursors were annotated and 20 miRNAs newly identified were validated. In addition, new target candidates for miRNAs newly identified in this study were proposed. Conclusions: The current study presents the first high-throughput small RNA sequencing study performed in castor bean to identify its miRNA population. It characterizes and increases the number of miRNAs and their isoforms identified in castor bean. The miRNA expression analysis provides a foundation for understanding castor bean miRNA organ-specific expression patterns. The present study offers an expanded picture of miRNAs for castor bean and other members in the family Euphorbiaceae. [ABSTRACT FROM AUTHOR]

Highlights: [•] Resveratrol facilitated memory formation and synaptic plasticity in 8–9month-old mice. [•] After resveratrol treatment, the levels of miR-124 and miR-134 were down-regulated in hippocampus. [•] The expression of CREB and BDNF was increased in the mice treated with resveratrol. [•] We showed a microRNA-based mechanism for the memory enhancement of resveratrol. [ABSTRACT FROM AUTHOR]

Aims: The impaired angiogenesis is one of the main factors affecting the healing of diabetic foot ulcer (DFU) wounds. Maggot debridement therapy (MDT) promotes granulation tissue growth and angiogenesis during DFU wound healing. Non-coding microRNAs can also promote local angiogenesis in DFU wounds by regulating wound repairing related gene expression. The purpose of this study was to investigate the mechanism of microRNAs in MDT promoting DFU wound angiogenesis.Methods: In this study, we applied MDT to treat DFU wound tissue and detect the expression of the miR-17-92 cluster. In vitro experiments, human umbilical vein endothelial cells (HUVECs) were treated with maggot excretions/secretions (ES), the miR-17-92 cluster and the predicted target gene expression were measured. Tube formation assay and cell scratch assay were performed when inhibition of miR-18a/19a or overexpression of thrombospondin-1 (TSP-1) were used in this study.Results: miR-18a/19a transcription significantly up-regulated and TSP-1 expression down-regulated in patients wound tissue and in HUVECs. Inhibition of miR-18a/19a or overexpression of TSP-1 partially blocked the migration and tube formation ability stimulated by ES.Conclusion: Targeted activation of miR-18a/19a transcription levels and subsequent regulation of TSP-1 expression may be a novel therapeutic strategy for DFU. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNAs (miRNA) participate in regulating diverse biological pathways by translational repression in animals. They have attracted increasing attention recently. However, little work has been done on the miRNA genes in agriculturally important pests. Because the transcripts of most miRNA genes are the products of type-II RNA polymerase, pri-miRNA has a poly(A) tail and appears in expressed sequence tags (EST). We developed a computational pipeline to identify miRNA genes from insect ESTs. First, 980,697 ESTs from 63 insects were collected and used to search the nr database. The ESTs which did not share significant similarities with any known protein-coding genes were treated as non-coding ESTs. Next, known mature miRNAs were used to align with non-coding ESTs. The ESTs which contain the sequence of mature miRNA were treated as candidate ESTs. Finally, putative precursors were extracted flanking the mature miRNA region in candidate ESTs and evaluated by the Triplet-SVM algorithm. As a result, 86 miRNAs from 30 insect species were found based on a strict criterion while 330 miRNAs from 51 species were found based on a loose criterion. Evolution analysis indicated that mir-467, mir-297 and mir-466 were the highest conserved miRNA families in insects. To confirm the reliability of putative insect miRNAs, the expression profile of nine predicted miRNAs in Locusta migratoria was investigated. Eight miRNAs were successfully detected by RT-PCR. Most miRNAs were expressed ubiquitously at all examined tissues and developmental stages whereas Lmi-mir-509 was specifically expressed in the thorax of the 2nd, 4th and 5th instars and adult locust. In all, our work reported an efficient computational strategy for predicting miRNA genes from insect ESTs and presented tens of miRNAs in diverse insect species which are expected to participate in many important physiological processes. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNAs (miRNAs) have recently received much interest for their role in post-transcriptional regulation. However, the study of miRNA transcription lags behind that of gene cloning and functional analysis. The MiR-281 in Drosophila melanogaster is located in the first intron of isoform RA of the ornithine decarboxylase antizyme (ODA) gene. ODA has three isoforms because of alternative transcription start sites (TSSs). Expression profile analysis indicated that miR-281 is not co-expressed with any ODA isoform. We amplified the primary transcripts of miR-281 using the RACE technique. The pri-miRNA is 2149bp with a poly (A) tail and a canonical polyadenylation signal (AATAAA). Chromatin immunoprecipitation analysis confirmed the binding of hypophosphorylated Pol-II and the transcription factor Myc at the core miR-281 promoter region. The abundance of miR-281 does not correlate, either positively or negatively, with the expression of any ODA isoform, indicating that ODA has little influence on the transcription of miR-281. [Copyright &y& Elsevier]