• Journal of Ginseng Research
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• v.37 no.2
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• pp.227-247
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• 2013

MicroRNAs (miRNAs) are a class of recently discovered non-coding small RNA molecules, on average approximately 21 nucleotides in length, which underlie numerous important biological roles in gene regulation in various organisms. The miRNA database (release 18) has 18,226 miRNAs, which have been deposited from different species. Although miRNAs have been identified and validated in many plant species, no studies have been reported on discovering miRNAs in Panax ginseng Meyer, which is a traditionally known medicinal plant in oriental medicine, also known as Korean ginseng. It has triterpene ginseng saponins called ginsenosides, which are responsible for its various pharmacological activities. Predicting conserved miRNAs by homology-based analysis with available expressed sequence tag (EST) sequences can be powerful, if the species lacks whole genome sequence information. In this study by using the EST based computational approach, 69 conserved miRNAs belonging to 44 miRNA families were identified in Korean ginseng. The digital gene expression patterns of predicted conserved miRNAs were analyzed by deep sequencing using small RNA sequences of flower buds, leaves, and lateral roots. We have found that many of the identified miRNAs showed tissue specific expressions. Using the insilico method, 346 potential targets were identified for the predicted 69 conserved miRNAs by searching the ginseng EST database, and the predicted targets were mainly involved in secondary metabolic processes, responses to biotic and abiotic stress, and transcription regulator activities, as well as a variety of other metabolic processes.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.482-489
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• 2017

Individual differences in drug responses are associated with genetic and epigenetic variability of pharmacogene expression. We aimed to identify the relevant miRNAs which regulate pharmacogenes associated with drug responses. The miRNA and mRNA expression profiles derived from data for normal and solid tumor tissues in The Cancer Genome Atlas (TCGA) Research Network. Predicted miRNAs targeted to pharmacogenes were identified using publicly available databases. A total of 95 pharmacogenes were selected from cholangiocarcinoma and colon adenocarcinoma, as well as kidney renal clear cell, liver hepatocellular, and lung squamous cell carcinomas. Through the integration analyses of miRNA and mRNA, 35 miRNAs were found to negatively correlate with mRNA expression levels of 16 pharmacogenes in normal bile duct, liver, colon, and lung tissues (p<0.05). Additionally, 36 miRNAs were related to differential expression of 32 pharmacogene mRNAs in those normal and tumorigenic tissues (p<0.05). These results indicate that changes in expression levels of miRNAs targeted to pharmacogenes in normal and tumor tissues may play a role in determining individual variations in drug response.

• BMB Reports
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• v.47 no.6
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• pp.311-317
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• 2014

microRNAs (miRNAs) are a class of small, non-coding RNAs that play critical posttranscriptional regulatory roles typically through targeting of the 3'-untranslated region of messenger RNA (mRNA). Mature miRNAs are known to be involved in global cellular processes, such as differentiation, proliferation, apoptosis, and organogenesis, due to their capacity to target multiple mRNAs. Thus, imbalances in the expression and/or activity of miRNAs are involved in the pathogenesis of numerous diseases, including pulmonary arterial hypertension (PAH). PAH is a progressive disease characterized by vascular remodeling due to excessive proliferation of pulmonary artery endothelial cells (PAECs) and pulmonary artery smooth muscle cells (PASMCs). Recently, studies have evaluated the roles of miRNAs involved in the pathogenesis of PAH in these pulmonary vascular cells. This review provides an overview of recent discoveries on the role of miRNAs in the pathogenesis of PAH and discusses the potential for miRNAs as therapeutic targets and biomarkers of PAH.

• Korean Journal of Acupuncture
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• v.39 no.4
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• pp.132-141
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• 2022

Objectives : Some acupoints are commonly utilized to treat a variety of diseases. The acupoints appear to have a wide range of effects caused by several mechanisms. The purpose of this study is to investigate into the potential role of microRNAs (miRNAs) in the multipotent effects of individual acupoint stimulation. Methods : We examined the miRNA expressions in the dorsal root ganglia (DRG) of neuropathic or inflammatory pain rats following ST36 and GB34 electroacupuncture (EA) stimulation. Neuropathic pain was induced by L5 spinal nerve ligation. Inflammatory pain was induced by knee joint injection of Complete Freund's adjuvant (CFA). EA was given under gaseous anesthesia with the same parameters (1mA, 2Hz, 30 min) in 5 consecutive days. Pain behaviors and miRNA expressions were analyzed. Results : In rats with neuropathic and inflammatory pain, EA treatments significantly enhanced the paw withdrawal threshold and weight-bearing force. After nerve injury, 36 miRNAs were upregulated in the DRG of neuropathic rats, while EA downregulated 10 of them. Furthermore, 14 miRNAs were downregulated following nerve damage, while one was increased by EA. 15 miRNAs were increased in the DRG of inflammatory rats following CFA injection, while 5 were downregulated by EA. Furthermore, 17 miRNAs were downregulated following CFA injection, while 7 were increased by EA. The miRNAs rno-miR-335, rno-miR-381-5p, rno-miR-1306-3p, and rno-miR-1839-3p were regulated by EA in both models. Conclusions : In two pain models, EA applied to ST36 and GB34 regulated miRNA expression differently. There appeared to be both acupoint-specific and non-specific miRNAs, and miRNA regulation of differential protein expression may modulate a variety of EA mechanisms.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.909-915
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• 2005

We investigated microRNA (miRNA) biogenesis of Epstein-Barr virus (EBV) which is the first virus shown to produce viral miRNAs. As expected, expression of all the reported EBV miRNAs were detected by Northen blot in an EBV-infected B cell line, B95-8; BHRF1-1, BHIU1-2, BHRF1-3, BART1, and BART2. The putative EBV pri-miRWAs and pre-miRNAs predicted from the known mature EBV miRNA sequences were detected by RT-PCR in B95-8 cells. Many animal miRNA genes exist as clusters of 2-7 genes and they are expressed polycistronically. As the EBV miRNAs are clustered in two regions of the EBV genome, we examined whether these clustered EBV miRNA genes are also expressed polycistronically. A long polycistronic transcript with the expected size (1602 bp) corresponding to the BHRF1-1~BHRF1-2~BHRF1-3 was amplified. However, any polycistronic transcript containing both BART1 and BART2 was detectable in B95-8. These results suggest that EBV miRNAs may be processed in a similar way with animal miRNAs and that some of the clustered EBV miRNAs can be transcribed polycistronically.

• BMB Reports
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• v.49 no.6
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• pp.311-318
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• 2016

Innate immune responses are primary, relatively limited, and specific responses to numerous pathogens and toxic molecules. Protein expression involved in these innate responses must be tightly regulated at both transcriptional level and post-transcriptional level to avoid the development of excessive inflammation that can be potentially harmful to the host. MicroRNAs are small noncoding RNAs (∼22 nucleotides [nts]) that participate in the regulation of numerous physiological responses by targeting specific messenger RNAs to suppress their translation. Recent work has shown that several negative regulators of transcription including microRNAs play important roles in inhibiting the exacerbation of inflammatory responses and in the maintenance of immunological homeostasis. This emerging research area will provide new insights on how microRNAs regulate innate immune signaling. It might show that dysregulation of microRNA synthesis is associated with the pathogenesis of inflammatory and infectious diseases. In this review, we focused on miR-146 and miR-125 and described the roles these miRNAs in modulating innate immune signaling. These microRNAs can control inflammatory responses and the outcomes of pathogenic infections.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9059-9064
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• 2014

MicroRNAs (miRNAs) are ubiquitously expressed small, non-coding RNAs that negatively regulate gene expression at a post transcriptional/translational level. They have emerging as playing crucial roles in cancer at all stages ranging from initiation to metastasis. As a tumor suppressor miRNA, aberrant expression of microRNA-29b (miR-29b) has been detected in various types of cancer, and its disturbance is related with tumor development and progression. In this review, we summarize the latest findings with regard to the tumor suppressor signatureof miR-29b and its regulatory mechanisms. Our review highlights the diverse relationships between miR-29b and its target genes in malignant tumors.

• Journal of Life Science
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• v.27 no.12
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• pp.1494-1499
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• 2017

Oral infection due to Candida albicans is a widely recognized and frequent cause of superficial infections of the oral mucosa (oral candidiasis). Although oral candidiasis is not a life-threatening fungemia, it can cause severe problems in individuals under certain conditions. MicroRNAs (miRNAs) are noncoding, small RNA molecules, which regulate the expression of other genes by inhibiting the translation of target mRNAs. The present study was designed to identify miRNAs in C. albicans and determine their possible roles in this organism. miRNA-sized small RNAs (msRNAs) were cloned in C. albicans by deep sequencing, and their secondary structures were analyzed. All the cloned msRNAs satisfied conditions required to qualify them as miRNAs. Bioinformatics analysis revealed that two of the most highly expressed C. albicans msRNAs, Ca-363 and Ca-2019, were located in the 3' untranslated region of the corticosteroid-binding protein 1 (CBP1) gene in a reverse orientation. miRNA mimics were transformed into C. albicans to investigate their RNA-inhibitory functions. RNA oligonucleotide-transformed C. albicans was then observed by fluorescent microscopy. Quantitative PCR analysis showed that these msRNAs did not inhibit CBP1 gene expression 4 hr and 8 hr after ectopic miRNA transformation. These results suggest that msRNAs in C. albicans possess an miRNA-triggered RNA interference gene-silencing function, which is distinct from that exhibited by other eukaryotic systems.

• Molecules and Cells
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• v.40 no.8
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• pp.587-597
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• 2017

MicroRNAs (miRNAs) are essential small RNA molecules that regulate the expression of target mRNAs in plants and animals. Here, we aimed to identify miRNAs and their putative targets in Hibiscus syriacus, the national flower of South Korea. We employed high-throughput sequencing of small RNAs obtained from four different tissues (i.e., leaf, root, flower, and ovary) and identified 33 conserved and 30 novel miRNA families, many of which showed differential tissuespecific expressions. In addition, we computationally predicted novel targets of miRNAs and validated some of them using 5' rapid amplification of cDNA ends analysis. One of the validated novel targets of miR477 was a terpene synthase, the primary gene involved in the formation of disease-resistant terpene metabolites such as sterols and phytoalexins. In addition, a predicted target of conserved miRNAs, miR396, is SHORT VEGETATIVE PHASE, which is involved in flower initiation and is duplicated in H. syriacus. Collectively, this study provides the first reliable draft of the H. syriacus miRNA transcriptome that should constitute a basis for understanding the biological roles of miRNAs in H. syriacus.

• BMB Reports
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• v.46 no.7
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• pp.338-345
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• 2013

microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by targeting the 3'-untranslated region of multiple target genes. Pathogenesis results from defects in several gene sets; therefore, disease progression could be prevented using miRNAs targeting multiple genes. Moreover, recent studies suggest that miRNAs reflect the stage of the specific disease, such as carcinogenesis. Cystic diseases, including polycystic kidney disease, polycystic liver disease, pancreatic cystic disease, and ovarian cystic disease, have common processes of cyst formation in the specific organ. Specifically, epithelial cells initiate abnormal cell proliferation and apoptosis as a result of alterations to key genes. Cysts are caused by fluid accumulation in the lumen. However, the molecular mechanisms underlying cyst formation and progression remain unclear. This review aims to introduce the key miRNAs related to cyst formation, and we suggest that miRNAs could be useful biomarkers and potential therapeutic targets in several cystic diseases.