On the classification of long non-coding RNAs

Long noncoding RNAs: a new regulatory code in osteoarthritis

It is reported that long noncoding RNAs (lncRNAs) were expressed aberrantly in cartilage of osteoarthritis (OA). Current evidence indicates that lncRNAs not only serve as positive or negative regulators of OA, but also crosstalk with multiple potential targets to impact on the critical events in OA process. This review summarized the lncRNAs identified in OA to date, discussed their influence on the survival of chondrocytes and synoviocytes, arthritis-associated factors, and angiogenesis, and indicated the potential in diagnosis, therapy, and prognosis.

LncRNA expression in the spinal cord modulated by minocycline in a mouse model of spared nerve injury

Neuropathic pain is a common and refractory chronic pain that affects millions of people worldwide. Its underlying mechanisms are still unclear, but they may involve long noncoding RNAs (lncRNAs), which play crucial roles in a variety of biological functions, including nociception. We used microarrays to investigate the possible interactions between lncRNAs and neuropathic pain and identified 22,213 lncRNAs and 19,528 mRNAs in the spinal cord in a mouse model of spared nerve injury (SNI)-induced neuropathic pain. The abundance levels of 183 lncRNAs and 102 mRNAs were significantly modulated by both SNI and administration of minocycline. A quantitative real-time polymerase chain reaction analysis validated expression changes in three lncRNAs (NR_015491, ENSMUST00000174263, and ENSMUST00000146263). Class distribution analysis of differentially expressed lncRNAs revealed intergenic lncRNAs as the largest category. Functional analysis indicated that SNI-induced gene regulations might be involved in the activities of cytokines (IL17A and IL17F) and chemokines (CCL2, CCL5, and CCL7), whereas minocycline might exert a pain-alleviating effect on mice through actin binding, thereby regulating nociception by controlling the cytoskeleton. Thus, lncRNAs might be responsible for SNI-induced neuropathic pain and the attenuation caused by minocycline. Our study could implicate lncRNAs as potential targets for future treatment of neuropathic pain.

Dysregulated long noncoding RNAs (lncRNAs) in hepatocellular carcinoma: implications for tumorigenesis, disease progression, and liver cancer stem cells

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours with a poor prognosis worldwide. While early stage tumours can be treated with curative approaches such as liver transplantation or surgical resection, these are only suitable for a minority of patients. Those with advanced stage disease are only suitable for supportive approaches and most are resistant to the conventional chemotherapy or radiotherapy. Liver cancer stem cells (LCSCs) are a small subset of cancer cells with unlimited differentiation ability and tumour forming potential. In order to develop novel therapeutic approaches for HCC, we need to understand how the cancer develops and why treatment resistance occurs. Using high-throughput sequencing techniques, a large number of dysregulated long noncoding RNAs (lncRNAs) have been identified, and some of which are closely linked to key aspects of liver cancer pathology, progression, outcomes and for the maintenance of cancer stem cell-like properties. In addition, some lncRNAs are potential biomarkers for HCC diagnosis and may serve as the therapeutic targets. This review summarizes data recently reported lncRNAs that might be critical for the maintenance of the biological properties of LCSCs.

Association between genetic polymorphisms of long non-coding RNA PRNCR1 and prostate cancer risk in a sample of the Iranian population

The aim of the present study was to determine whether there is an association between the long non-coding RNA (lncRNA) prostate cancer-associated non-coding RNA 1 (PRNCR1) polymorphisms and prostate cancer (PCa) risk in a sample of the Iranian population. This case-control study was performed on 178 patients with PCa and 180 subjects with benign prostatic hyperplasia (BPH). Genotyping assay was performed by polymerase chain reaction-restriction fragment length polymorphism. The findings indicated that the GG genotype of the rs13252298 A>G variant significantly increased the risk of PCa (odds ratio=3.49, 95% confidence interval: 1.79-6.81, P=0.0001) compared with AA+AG. As regards the rs1456315 G>A polymorphism, the AG genotype and G allele significantly increased the risk of PCa. As regards the rs7841060 T>G variant, the findings demonstrated that this TG genotype and the G allele significantly increased the risk of PCa. The rs7007694 T>C variant was not found to be associated with the risk of PCa. Haplotype analysis indicated that GTGA and GTGG significantly increased the risk of PCa compared with rs1456315A/rs7007694T/rs7841060T/rs13252298G (ATTG). The PRNCR1 variants were not found to be significantly associated with the clinicopathological characteristics of PCa patients. In conclusion, our findings support an association between PRNCR1 variants and the risk of PCa in a sample of the Iranian population.

Exon Mapping in Long Noncoding RNAs Using Digital Filters

Long noncoding RNAs (lncRNAs) which were initially dismissed as "transcriptional noise" have become a vital area of study after their roles in biological regulation were discovered. Long noncoding RNAs have been implicated in various developmental processes and diseases. Here, we perform exon mapping of human lncRNA sequences (taken from National Center for Biotechnology Information GenBank) using digital filters. Antinotch digital filters are used to map out the exons of the lncRNA sequences analyzed. The period 3 property which is an established indicator for locating exons in genes is used here. Discrete wavelet transform filter bank is used to fine-tune the exon plots by selectively removing the spectral noise. The exon locations conform to the ranges specified in GenBank. In addition to exon prediction, G-C concentrations of lncRNA sequences are found, and the sequences are searched for START and STOP codons as these are indicators of coding potential.

NEAT1 regulates cell proliferation and apoptosis of ovarian cancer by miR-34a-5p/BCL2

Background

Nuclear enriched abundant transcript 1 (NEAT1) has been demonstrated to act as a tumor inhibitor in many cancers. However, the role of NEAT1 in the development of ovarian cancer (OC) remains far from being elaborated. Hence, the aim of this study is to investigate the expression and function of NEAT1 in OC.

Materials and methods

The expression level of NEAT1 was determined by quantitative real-time polymerase chain reaction in OC cell lines. MTT assay, caspase-3 activity assay, and flow cytometry analysis were conducted to investigate the effects of NEAT1, miR-34a-5p, or B-cell lymphoma-2 (BCL2) on OC cell proliferation and apoptosis. Luciferase reporter assay was used to confirm the interaction of NEAT1, BCL2, and miR-34a-5p in OC cells.

Results

NEAT1 was significantly upregulated in OC cell lines. NEAT1 overexpression promoted proliferation by increasing the proportion of cells in S phase and suppressed apoptosis of OC cells, while knockdown of NEAT1 had the opposite effect. In addition, NEAT1 was demonstrated to directly interact with miR-34a-5p and exert its oncogenic role in OC by negatively regulating miR-34a-5p. Moreover, miR-34a-5p could directly target BCL2 and suppressed its expression. miR-34a-5p overexpression suppressed OC cell proliferation and triggered apoptosis by targeting BCL2. Furthermore, NEAT1 knockdown suppressed BCL2 expression, while anti-miR-34a-5p dramatically abated the inhibitory effect of si-NEAT1 on BCL2 expression.

Conclusion

NEAT1 regulated proliferation and apoptosis of OC cells by miR-34a-5p/BCL2, providing a potential therapeutic approach for the treatment of OC patients.

Epigenetics and Bone Remodeling

PURPOSE OF REVIEW

Bone remodeling is a diverse field of study with many direct clinical applications; past studies have implicated epigenetic alterations as key factors of both normal bone tissue development and function and diseases of pathologic bone remodeling. The purpose of this article is to review the most important recent advances that link epigenetic changes to the bone remodeling field.

RECENT FINDINGS

Epigenetics describes three major phenomena: DNA modification via methylation, histone side chain modifications, and short non-coding RNA sequences which work in concert to regulate gene transcription in a heritable fashion. Recent findings include the role of DNA methylation changes of Wnt, RANK/RANKL, and other key signaling pathways, epigenetic regulation of osteoblast and osteoclast differentiation, and others. Although much work has been done, much is still unknown. Future epigenome-wide studies should focus on extending the tissue coverage, integrating multiple epigenetic analyses with transcriptome data, and working to uncover epigenetic changes linked with early events in aberrant bone remodeling.

Identification and allelic dissection uncover roles of lncRNAs in secondary growth of Populus tomentosa

Long non-coding RNAs (lncRNAs) function in various biological processes. However, their roles in secondary growth of plants remain poorly understood. Here, 15,691 lncRNAs were identified from vascular cambium, developing xylem, and mature xylem of Populus tomentosa with high and low biomass using RNA-seq, including 1,994 lncRNAs that were differentially expressed (DE) among the six libraries. 3,569 cis-regulated and 3,297 trans-regulated protein-coding genes were predicted as potential target genes (PTGs) of the DE lncRNAs to participate in biological regulation. Then, 476 and 28 lncRNAs were identified as putative targets and endogenous target mimics (eTMs) of Populus known microRNAs (miRNAs), respectively. Genome re-sequencing of 435 individuals from a natural population of P. tomentosa found 34,015 single nucleotide polymorphisms (SNPs) within 178 lncRNA loci and 522 PTGs. Single-SNP associations analysis detected 2,993 associations with 10 growth and wood-property traits under additive and dominance model. Epistasis analysis identified 17,656 epistatic SNP pairs, providing evidence for potential regulatory interactions between lncRNAs and their PTGs. Furthermore, a reconstructed epistatic network, representing interactions of 8 lncRNAs and 15 PTGs, might enrich regulation roles of genes in the phenylpropanoid pathway. These findings may enhance our understanding of non-coding genes in plants.

LncRNA NEAT1 Regulates Cell Viability and Invasion in Esophageal Squamous Cell Carcinoma through the miR-129/CTBP2 Axis

Background

Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) was reported to be aberrantly upregulated and promote esophageal squamous cell carcinoma (ESCC) cell progression. Nevertheless, the molecular mechanism of NEAT1 involved in the competing endogenous RNA (ceRNA) regulatory network in ESCC progression remains poorly defined.

Methods

The expressions of NEAT1, miR-129, and C-terminal-binding protein 2 (CTBP2) in ESCC cells were examined by qRT-PCR. The effects of NEAT1 knockdown and miR-129 overexpression, or along with CTBP2 upregulation, on ESCC cell viability and invasion were explored by CCK-8 and transwell invasion assays, respectively. Luciferase reporter assay in combination with RIP was performed to confirm the interaction between NEAT1, miR-129, and CTBP2.

Results

NEAT1 and CTBP2 were upregulated and miR-129 was downregulated in ESCC cells. Either NEAT1 knockdown or miR-129 overexpression suppressed ESCC cell viability and invasion. Moreover, NEAT1 functioned as an endogenous sponge to downregulate miR-129 by competitively binding to miR-129, thereby leading to the derepression of CTBP2, a target of miR-129. CTBP2 restoration overturned cell viability and invasion suppression mediated by NEAT1 knockdown or miR-129 overexpression.

Conclusion

LncRNA NEAT1 regulated ESCC cell viability and invasion via the miR-129/CTBP2 axis, contributing to the better understanding of the molecular mechanism of ESCC pathogenesis and progression.

Differentially expressed long non‑coding RNAs and mRNAs in patients with IgA nephropathy

Long non‑coding RNAs (lncRNAs) have been reported to serve a crucial role in renal diseases; however, their role in immunoglobulin A nephropathy (IgAN) remains unclear. In the present study, peripheral blood mononuclear cells (PBMCs) were collected from both patients with IgAN and healthy controls. A microarray analysis was then performed to identify differentially expressed lncRNAs and mRNAs in PBMCs, which were confirmed by quantitative polymerase chain reaction. In addition, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and lncRNA‑mRNA co‑expression network analyses were conducted. The present study identified 167 differentially expressed lncRNAs and 94 differentially expressed mRNAs. Numerous GO terms, including innate immune response, inflammatory response, IPAF inflammasome complex and UDP‑galactose:β‑N‑acetylglucosamine β‑1, and 3‑galactosyltransferase activity, were significantly enriched in the differentially expressed mRNAs. The top five KEGG signaling pathways included nucleotide‑binding oligomerization domain‑like receptor signaling pathway, hematopoietic cell lineage, inflammatory bowel disease, tumor necrosis factor signaling pathway and other types of O‑glycan biosynthesis. In addition, a total of 149 lncRNAs were shown to interact with 7 mRNAs that were associated with the 'innate immune response' GO term. The results of the present study demonstrated that differentially expressed lncRNAs and mRNAs may have a role in the development of IgAN. These results may aid in the elucidation of a basic pathogenic mechanism, the identification of possible biomarkers and the generation of potential novel treatment strategies for IgAN.

Long non-coding RNAs in Colorectal Cancer: Progression and Future Directions

Identification of the colorectal adenoma-carcinoma sequence with its corresponding genetic and epigenetic alterations has significantly increased our knowledge of the etiopathogenesis of colorectal cancer (CRC). However, the molecular mechanisms of colorectal carcinogenesis and metastasis haven't been clearly elucidated. Long non-coding ribonucleic acids (lncRNAs) are key participants of gene regulations rather than “noises”. Accumulative studies have implicated that the aberrant expressions of lncRNAs are tightly corelated to CRC screening, diagnosis, prognosis and therapeutic outcomes. Our review focuses on recent findings on the involvement of lncRNAs in CRC oncogenesis and the lncRNA-based clinical implications in patients with CRC.

Long Non-coding RNA in Liver Metabolism and Disease: Current Status

Long non-coding RNAs (lncRNAs) are comprised of RNA transcripts exceeding 200 nucleotides in length but lacking identifiable open reading frames (with rare exceptions). Herein, we highlight emerging evidence demonstrating that lncRNAs are critical regulators of liver metabolic function and diseases. We summarize current knowledges about dysregulated lncRNAs and outline the underlying molecular mechanisms by which lncRNAs control hepatic lipid ad glucose metabolism, as well as cholestatic liver disease. lncLSTR, Lnc18q22.2, SRA, HULC, MALAT1, lncLGR, MEG3, and H19, lncHR1, lnc-HC, APOA1-AS, DYNLRB2-2, and LeXis are included in the discussion.

Identification of long non-coding RNA in rice lines resistant to Rice blast pathogen Maganaporthe oryzae

Rice blast disease caused by a fungus Magnaporthae oryzae is one of the most important biotic factors that severely damage the rice crop. Several molecular approaches are now being applied to tackle this issue in rice. It is of interest to study long non-coding RNA (lncRNA) in rice to control the disease. lncRNA, a non-coding transcript that does not encode protein, is known to play an important role in gene regulation of various biological processes. Here we describe a computational pipeline to identify lncRNA from a resistant rice line. The number of lncRNA found in resistant line was 1429, 1927 and 1981 in mock and M. oryzae (ZB13 and Zhong) inoculated samples, respectively. Functional classification of these lncRNA reveals a higher number of long intergenic non-coding RNA compared to antisense lncRNA in both mock and M. oryzae inoculated resistant rice lines. Many intergenic lncRNA candidates were identified from resistant rice line and their role to regulate the resistance mechanism in rice during M. oryzae invasion is implied.

TUG1 promotes osteosarcoma tumorigenesis by upregulating EZH2 expression via miR-144-3p

lncRNA-TUG1 (Taurine upregulated 1) is up regulated and highly correlated with poor prognosis and disease status in osteosarcoma. TUG1 knockdown inhibits osteosarcoma cell proliferation, migration and invasion, and promotes apoptosis. However, its mechanism of action has not been well addressed. Growing evidence documented that lncRNA works as competing endogenous (ce)RNAs to modulate the expression and biological functions of miRNA. As a putative combining target of TUG1, miR-144-3p has been associated with the progress of osteosarcoma. To verify whether TUG1 functions through regulating miR-144-3p, the expression levels of TUG1 and miR-144-3p in osteosarcoma tissues and cell lines were determined. TUG1 was upregulated in osteosarcoma tissues and cell lines, and negatively correlated with miR-144-3p. TUG1 knockdown induced miR-144-3p expression in MG63 and U2OS cell lines. Results from dual luciferase reporter assay, RNA-binding protein immuno precipitation (RIP) and applied biotin-avidin pull-down system confirmed TUG1 regulated miR-144-3p expression through direct binding. EZH2, a verified target of miR-144-3p was upregulated in osteosarcoma tissues and negatively correlated with miR-144-3p. EZH2 was negatively regulated by miR-144-3p and positively regulated by TUG1. Gain-and loss-of-function experiments were performed to analyze the role of TUG1, miR-144-3p and EZH2 in the migration and EMT of osteosarcoma cells. EZH2 overexpression partly abolished TUG1 knockdown or miR-144-3p overexpression induced inhibition of migration and EMT in osteosarcoma cells. In addition, TUG1 knockdown represses the activation of Wnt/β-catenin pathway, which was reversed by EZH2 over expression. The activator of Wnt/β-catenin pathway LiCl could partially block the TUG1-knockdown induced osteosarcoma cell migration and EMT inhibition. In conclusion, our results showed that TUG1 plays an important role in osteosarcoma development through miRNA-144-3p/EZH2/Wnt/β-catenin pathway.

Long non-coding RNAs in hepatocellular carcinoma: Potential roles and clinical implications

Long non-coding RNAs (lncRNAs) are a subgroup of non-coding RNA transcripts greater than 200 nucleotides in length with little or no protein-coding potential. Emerging evidence indicates that lncRNAs may play important regulatory roles in the pathogenesis and progression of human cancers, including hepatocellular carcinoma (HCC). Certain lncRNAs may be used as diagnostic or prognostic markers for HCC, a serious malignancy with increasing morbidity and high mortality rates worldwide. Therefore, elucidating the functional roles of lncRNAs in tumors can contribute to a better understanding of the molecular mechanisms of HCC and may help in developing novel therapeutic targets. In this review, we summarize the recent progress regarding the functional roles of lncRNAs in HCC and explore their clinical implications as diagnostic or prognostic biomarkers and molecular therapeutic targets for HCC.

The prognostic value of long noncoding RNAs in prostate cancer: a systematic review and meta-analysis

The abnormally expressed LncRNAs played irreplaceable roles in the prognosis of prostate cancer (PCa). Therefore, we conducted this systematic review and meta-analysis to summarize the association between the expression of LncRNAs, prognosis and clinicopathology of PCa. 18 eligible studies were recruited into our analysis, including 18 on prognosis and 9 on clinicopathological features. Results indicated that aberrant expression of LncRNAs was significantly associated with biochemical recurrence-free survival (BCR-FS) (HR = 1.55, 95%CI: 1.01-2.37, P < 0.05), recurrence free survival (RSF) (HR = 3.07, 95%CI: 1.07-8.86, P < 0.05) and progression free survival (PFS) (HR = 2.34, 95%CI: 1.94-2.83, P < 0.001) in PCa patients. LncRNAs expression level was correlated with several vital clinical features, like tumor size (HR = 0.52, 95%CI: 0.28-0.95, P = 0.03), distance metastasis (HR = 4.55, 95%CI: 2.26-9.15, P < 0.0001) and histological grade (HR = 6.23, 95% CI: 3.29-11.82, P < 0.00001). Besides, down-regulation of PCAT14 was associated with the prognosis of PCa [over survival (HR = 0.77, 95%CI: 0.63-0.95, P = 0.01), BCR-FS (HR = 0.61, 95%CI: 0.48-0.79, P = 0.0001), prostate cancer-specific survival (HR = 0.64, 95%CI: 0.48-0.85, P = 0.002) and metastasis-free survival (HR = 0.61, 95%CI: 0.50-0.74, P < 0.00001)]. And, the increased SChLAP1 expression could imply the worse BCR-FS (HR = 2.54, 95%CI: 1.82-3.56, P < 0.00001) and correlate with Gleason score (< 7 vs ≥ 7) (OR = 4.11, 95% CI: 1.94-8.70, P = 0.0002). Conclusively, our present work demonstrated that LncRNAs transcription level might be potential prognostic markers in PCa.

Epigenetics in osteoarthritis: Potential of HDAC inhibitors as therapeutics

Osteoarthritis (OA) is the most common joint disease and the leading cause of chronic disability in middle-aged and older populations worldwide. The development of disease modifying therapy for OA is in its infancy largely because the regulatory mechanisms for the molecular effectors of OA pathogenesis are poorly understood. Recent studies identified epigenetic events as a critical regulator of molecular players involved in the induction and development of OA. Epigenetic mechanisms include DNA methylation, non-coding RNA and histone modifications. The aim of this review is to briefly highlight the recent advances in the epigenetics of cartilage and potential of HDACs (Histone deacetylases) inhibitors in the therapeutic management of OA. We summarize the recent studies utilizing HDAC inhibitors as potential therapeutics for inhibiting disease progression and preventing the cartilage destruction in OA. HDACs control normal cartilage development and homeostasis and understanding the impact of HDACs inhibitors on the disease pathogenesis is of interest because of its importance in affecting overall cartilage health and homeostasis. These findings also shed new light on cartilage disease pathophysiology and provide substantial evidence that HDACs may be potential novel therapeutic targets in OA.

FARNA: knowledgebase of inferred functions of non-coding RNA transcripts

Non-coding RNA (ncRNA) genes play a major role in control of heterogeneous cellular behavior. Yet, their functions are largely uncharacterized. Current available databases lack in-depth information of ncRNA functions across spectrum of various cells/tissues. Here, we present FARNA, a knowledgebase of inferred functions of 10,289 human ncRNA transcripts (2,734 microRNA and 7,555 long ncRNA) in 119 tissues and 177 primary cells of human. Since transcription factors (TFs) and TF co-factors (TcoFs) are crucial components of regulatory machinery for activation of gene transcription, cellular processes and diseases in which TFs and TcoFs are involved suggest functions of the transcripts they regulate. In FARNA, functions of a transcript are inferred from TFs and TcoFs whose genes co-express with the transcript controlled by these TFs and TcoFs in a considered cell/tissue. Transcripts were annotated using statistically enriched GO terms, pathways and diseases across cells/tissues based on guilt-by-association principle. Expression profiles across cells/tissues based on Cap Analysis of Gene Expression (CAGE) are provided. FARNA, having the most comprehensive function annotation of considered ncRNAs across widest spectrum of human cells/tissues, has a potential to greatly contribute to our understanding of ncRNA roles and their regulatory mechanisms in human. FARNA can be accessed at: http://cbrc.kaust.edu.sa/farna

Discovering DNA methylation patterns for long non-coding RNAs associated with cancer subtypes

Despite growing evidence demonstrates that the long non-coding ribonucleic acids (lncRNAs) are critical modulators for cancers, the knowledge about the DNA methylation patterns of lncRNAs is quite limited. We develop a systematic analysis pipeline to discover DNA methylation patterns for lncRNAs across multiple cancer subtypes from probe, gene and network levels. By using The Cancer Genome Atlas (TCGA) breast cancer methylation data, the pipeline discovers various DNA methylation patterns for lncRNAs across four major subtypes such as luminal A, luminal B, her2-enriched as well as basal-like. On the probe and gene level, we find that both differentially methylated probes and lncRNAs are subtype specific, while the lncRNAs are not as specific as probes. On the network level, the pipeline constructs differential co-methylation lncRNA network for each subtype. Then, it identifies both subtype specific and common lncRNA modules by simultaneously analyzing multiple networks. We show that the lncRNAs in subtype specific and common modules differ greatly in terms of topological structure, sequence conservation as well as expression. Furthermore, the subtype specific lncRNA modules serve as biomarkers to improve significantly the accuracy of breast cancer subtypes prediction. Finally, the common lncRNA modules associate with survival time of patients, which is critical for cancer therapy.

Long Noncoding RNA and Cancer: A New Paradigm

In addition to mutations or aberrant expression in the protein-coding genes, mutations and misregulation of noncoding RNAs, in particular long noncoding RNAs (lncRNA), appear to play major roles in cancer. Genome-wide association studies of tumor samples have identified a large number of lncRNAs associated with various types of cancer. Alterations in lncRNA expression and their mutations promote tumorigenesis and metastasis. LncRNAs may exhibit tumor-suppressive and -promoting (oncogenic) functions. Because of their genome-wide expression patterns in a variety of tissues and their tissue-specific expression characteristics, lncRNAs hold strong promise as novel biomarkers and therapeutic targets for cancer. In this article, we have reviewed the emerging functions and association of lncRNAs in different types of cancer and discussed their potential implications in cancer diagnosis and therapy. Cancer Res; 77(15); 3965-81. ©2017 AACR.

The difference in expression of long noncoding RNAs in rat semen induced by high-fat diet was associated with metabolic pathways

Background

Obesity, a common metabolic disease, is a known cause of male infertility due to its associated health risk. Long noncoding RNAs (lncRNAs) have also been reported to be associated with male reproductive diseases; however, their role in the association between high-fat diet-induced obesity (DIO) and male reproduction remains unclear.

Methods

We used microarray analysis to compare the expression levels of lncRNAs and mRNAs in the spermatozoa of rats with DIO and normal rats. We selected a few lncRNAs that were obviously up-regulated or down-regulated, and then used RT-PCR to verify the accuracy of their expression. We then performed a functional enrichment analysis of the differentially expressed mRNAs using gene ontology and pathway analysis. Finally, target gene predictive analysis was used to explore the relationship between lncRNAs and mRNAs.

Results

The results revealed a statistically significant difference in the fasting blood glucose level in rats with DIO and control rats. We found that 973 lncRNAs and 2,994 mRNAs were differentially expressed in the sperm samples of the DIO rats, compared to the controls. GO enrichment analysis revealed 263 biological process terms, 39 cellular component terms, and 40 molecular function terms (p < 0.01) in the differentially expressed mRNAs. The pathway analysis showed that metabolic pathways were most enriched in protein-coding genes.

Discussion

To the best of our knowledge, this is the first report to show differences in the expression levels of lncRNAs and mRNAs in the sperms of rats with DIO and normal rats, and to determine the expression profile of lncRNAs in the sperm of rats with DIO. Our results have revealed a number of lncRNAs and pathways associated with obesity-induced infertility, including metabolic pathways. These pathways could be new candidates that help cope with and investigate the mechanisms behind the progression of obesity-induced male infertility.

LncRNA ODRUL Contributes to Osteosarcoma Progression through the miR-3182/MMP2 Axis

Recent findings have shown that lncRNA dysregulation is involved in many cancers, including osteosarcoma (OS). In a previous study, we reported a novel lncRNA, ODRUL, that could promote doxorubicin resistance in OS. We now report the function and underlying mechanism of ODRUL in regulating OS progression. We show that ODRUL is upregulated in OS tissues and cell lines and correlates with poor prognosis. ODRUL knockdown significantly inhibits OS cell proliferation, migration, invasion, and tumor growth in vitro and in vivo by decreasing matrix metalloproteinase (MMP) expression. A microarray screen combined with online database analysis showed that miR-3182 is upregulated and MMP2 is downregulated in sh-ODRUL-expressing MG63 cells and that miR-3182 harbors potential binding sites for ODRUL and the 3' UTR of MMP2 mRNA. In addition, miR-3182 expression and function are inversely correlated with ODRUL expression in vitro and in vivo. A luciferase reporter assay demonstrated that ODRUL could directly interact with miR-3182 and upregulate MMP2 expression via its competing endogenous RNA activity on miR-3182 at the posttranscriptional level. Taken together, our study has elucidated the role of oncogenic ODRUL in OS progression and may provide a new target in OS therapy.

Modulation of IGF2BP1 by long non-coding RNA HCG11 suppresses apoptosis of hepatocellular carcinoma cells via MAPK signaling transduction

Hepatocellular carcinoma (HCC) is a common malignancy of the liver. HCG11 is a member of long non-coding family, upregulation of which in HCC was proved by our previous study. In the present study, the role of HCG11 in the development of HCC was detected by focusing on the interaction between HCG11 and its target protein insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1). The expression status of HCG11 and IGF2BP1 was first investigated with clinical HCC samples. Then the expressions of HCG11 and IGF2BP1 were both inhibited in the human HCC cell line HepG2 and the cell viability, proliferation, apoptosis and metastasis potential of HepG2 cells were assessed. At molecular level, the expression levels of p-ERK, p-JNK, p-p38, p21 and cleaved caspase-3 were also determined to explain the pathways involved in the function of HCG11 in the progression of HCC. Expression of HCG11 and IGF2BP1 were significantly higher in HCC tissues than those in para-tumor tissues. Knockdown of both indicators led to decreased cell viability, proliferation, and migration ability in HepG2 cells while the cell apoptosis and G1 cell cycle arrest were induced after knockdown of HCG11 and IGF2BP1. In addition, suppressed activity of HCG11 and IGF2BP1 blocked the phosphorylation of anti-apoptosis factors, including ERK, JNK and p38 while the mitochondrial apoptosis in HCC cells was initiated by activation of p21 and cleaved caspase-3. HCG11 exerted its effect on HCC via interaction with IGF2BP1, leading to activation of MAPK signaling, which eventually promoted the progression of HCC.

DES-ncRNA: A knowledgebase for exploring information about human micro and long noncoding RNAs based on literature-mining

Noncoding RNAs (ncRNAs), particularly microRNAs (miRNAs) and long ncRNAs (lncRNAs), are important players in diseases and emerge as novel drug targets. Thus, unraveling the relationships between ncRNAs and other biomedical entities in cells are critical for better understanding ncRNA roles that may eventually help develop their use in medicine. To support ncRNA research and facilitate retrieval of relevant information regarding miRNAs and lncRNAs from the plethora of published ncRNA-related research, we developed DES-ncRNA ( www.cbrc.kaust.edu.sa/des_ncrna ). DES-ncRNA is a knowledgebase containing text- and data-mined information from public scientific literature and other public resources. Exploration of mined information is enabled through terms and pairs of terms from 19 topic-specific dictionaries including, for example, antibiotics, toxins, drugs, enzymes, mutations, pathways, human genes and proteins, drug indications and side effects, mutations, diseases, etc. DES-ncRNA contains approximately 878,000 associations of terms from these dictionaries of which 36,222 (5,373) are with regards to miRNAs (lncRNAs). We provide several ways to explore information regarding ncRNAs to users including controlled generation of association networks as well as hypotheses generation. We show an example how DES-ncRNA can aid research on Alzheimer disease and suggest potential therapeutic role for Fasudil. DES-ncRNA is a powerful tool that can be used on its own or as a complement to the existing resources, to support research in human ncRNA. To our knowledge, this is the only knowledgebase dedicated to human miRNAs and lncRNAs derived primarily through literature-mining enabling exploration of a broad spectrum of associated biomedical entities, not paralleled by any other resource.

Overexpression of long noncoding RNA PEG10 promotes proliferation, invasion and metastasis of hypopharyngeal squamous cell carcinoma

The present study aimed to investigate the impact of overexpression of long noncoding RNA PEG10 (lncRNA PEG10) on the proliferation, invasion and metastasis of hypopharyngeal squamous cell carcinoma (HSCC). Quantitative reverse transcription polymerase chain reaction was used to quantify lncRNA PEG10 expression levels in HSCC tumor tissues samples, para-carcinoma tissue samples and the HSCC FaDu cell line. Cell proliferation assays, Transwell invasion assays and wound healing assays were used to evaluate the effects of lncRNA PEG10 on FaDu cells in vitro. In 56 eligible patients, lncRNA PEG10 was expressed at higher levels in HSCC tumor tissues compared with para-carcinoma tissues, and significant associations were observed between increased tumor expression of lncRNA PEG10 and primary tumor size, lymph node status and tumor node metastasis stage. In the in vitro experimental studies, enhanced expression of lncRNA PEG10 was significantly associated with increased proliferation, invasion and metastasis of FaDu cells. lncRNA PEG10 was upregulated in HSCC, and its overexpression in HSCC cells promoted an increase in the tumorigenic activities of proliferation, invasion and migration. The potential underlying mechanisms require investigation in future studies.

Long non-coding RNAs in cutaneous melanoma: clinical perspectives

Metastatic melanoma of the skin has a high mortality despite the recent introduction of targeted therapy and immunotherapy. Long non-coding RNAs (lncRNAs) are defined as transcripts of more than 200 nucleotides in length that lack protein-coding potential. There is growing evidence that lncRNAs play an important role in gene regulation, including oncogenesis. We present 13 lncRNA genes involved in the pathogenesis of cutaneous melanoma through a variety of pathways and molecular interactions. Some of these lncRNAs are possible biomarkers or therapeutic targets for malignant melanoma.

Non-coding RNA regulation of T cell biology: Implications for age-associated cardiovascular diseases

Prevalence of age-associated cardiovascular diseases (CVD) has dramatically increased as a result of improvements in life expectancy. Chronic inflammation is a shared pathophysiological feature of age-associated CVDs, indicating a role for the immune system in the onset and development of CVDs. Indeed, ageing elicits profound changes in both the cardiovascular and immune system, especially in the T cell compartment. Although such changes have been well described at the cellular level, the molecular mechanisms underlying immune-mediated cardiovascular ageing remain largely unexplored. Non-coding RNAs (ncRNAs) comprise a heterogeneous family of RNA transcripts that regulate gene expression at the epigenetic, transcriptional, post-transcriptional, and post-translational levels. Non-coding RNAs have recently emerged as master modulators of T cell immunity. In this review, the state-of-the-art knowledge on ncRNA regulatory effects over T cell differentiation, function, and ageing in the context of age-associated CVDs, such as atherosclerosis, acute coronary syndromes, and heart failure, is discussed.

Overexpression of LINC00152 correlates with poor patient survival and knockdown impairs cell proliferation in lung cancer

We employed RNA sequencing analysis to reveal dysregulated lncRNAs in lung cancer utilizing 461 lung adenocarcinomas and 156 normal lung tissues from 3 separate cohorts. We found that LINC00152 was highly overexpressed in lung tumors as compared to their adjacent normal tissues. Patients with high LINC00152 expression demonstrate a significantly poorer survival than those with low expression. We verified the diagnostic/prognostic potential of LINC00152 expression in an independent cohort of lung tumor tissues using quantitative RT-PCR. After knockdown of LINC00152 using siRNAs in lung cancer cell lines, both cell proliferation and colony formation were decreased. Cell fractionation and qRT-PCR analysis indicated that LINC00152 is found mainly in the cytoplasm. Treatment with Trichostatin A in cell lines having low LINC00152 expression indicated that histone acetylation may be one mechanism underlying LINC00152 overexpression in NSCLC. Western blot analyses indicated that p38a, STAT1, STAT3, CREB1, CCNE1 and c-MYC proteins were decreased after LINC00152 siRNA treatment. Our study indicates LINC00152 plays an important role in lung tumor growth and is potentially a diagnostic/prognostic marker. Further characterization of LINC00152 in regulating its target proteins may provide a novel therapeutic target of lung cancer.

Noncoding RNAs in Cancer Diagnosis

The accuracy and efficiency of tumor treatment depends mainly on early and precise diagnosis. Although histopathology is always the gold standard for cancer diagnosis, noninvasive biomarkers represent an opportunity for early detection and molecular staging of cancer. Besides the classical tumor markers, noncoding RNAs (ncRNAs) emerge to be a novel category of biomarker for cancer diagnosis since the dysregulation of ncRNAs is closely associated with the development and progression of human cancers such as liver, lung, breast, gastric, and other kinds of cancers. In this chapter, we will summarize the different types of ncRNAs in the diagnosis of major human cancers. In addition, we will introduce the recent advances in the detection and applications of circulating serum or plasma ncRNAs and non-blood fluid ncRNAs because the noninvasive body fluid-based assays are easy to examine for cancer diagnosis and monitoring.

Fingerprint of long non-coding RNA regulated by cyclic mechanical stretch in human aortic smooth muscle cells: implications for hypertension

Emerging evidence suggests that long non-coding RNAs (lncRNAs) represent a cellular hub coordinating various cellular processes that are critical in health and disease. Mechanical stress triggers changes in vascular smooth muscle cells (VSMCs) that in turn contribute to pathophysiological changes within the vasculature. We sought to evaluate the role that lncRNAs play in mechanical stretch-induced alterations of human aortic smooth muscle cells (HASMCs). RNA (lncRNA and mRNA) samples isolated from HASMCs that had been subjected to 10 or 20% elongation (1 Hz) for 24 h were profiled with the Arraystar Human LncRNA Microarray V3.0. LncRNA expression was quantified in parallel via qRT-PCR. Of the 30,586 human lncRNAs screened, 580 were differentially expressed (DE, P < 0.05) in stretched HASMCs. Amongst the 26,109 protein-coding transcripts evaluated, 25 of those DE were associated with 25 of the aforementioned DE lncRNAs (P < 0.05). Subsequent Kyoto Encyclopedia of Genes and Genomes analysis revealed that the DE mRNAs were largely associated with the tumor necrosis factor signaling pathway and inflammation. Gene Ontology analysis indicated that the DE mRNAs were associated with cell differentiation, stress response, and response to external stimuli. We describe the first transcriptome profile of stretch-induced changes in HASMCs and provide novel insights into the regulatory switches that may be fundamental in governing aberrant VSMC remodeling.

An Immune-Related Six-lncRNA Signature to Improve Prognosis Prediction of Glioblastoma Multiforme

Recent studies have demonstrated the utility and superiority of long non-coding RNAs (lncRNAs) as novel biomarkers for cancer diagnosis, prognosis, and therapy. In the present study, the prognostic value of lncRNAs in glioblastoma multiforme was systematically investigated by performing a genome-wide analysis of lncRNA expression profiles in 419 glioblastoma patients from The Cancer Genome Atlas (TCGA) project. Using survival analysis and Cox regression model, we identified a set of six lncRNAs (AC005013.5, UBE2R2-AS1, ENTPD1-AS1, RP11-89C21.2, AC073115.6, and XLOC_004803) demonstrating an ability to stratify patients into high- and low-risk groups with significantly different survival (median 0.899 vs. 1.611 years, p = 3.87e-09, log-rank test) in the training cohort. The six-lncRNA signature was successfully validated on independent test cohort of 219 patients with glioblastoma, and it revealed superior performance for risk stratification with respect to existing lncRNA-related signatures. Multivariate Cox and stratification analysis indicated that the six-lncRNA signature was an independent prognostic factor after adjusting for other clinical covariates. Further in silico functional analysis suggested that the six-lncRNA signature may be involved in the immune-related biological processes and pathways which are very well known in the context of glioblastoma tumorigenesis. The identified lncRNA signature had important clinical implication for improving outcome prediction and guiding the tailored therapy for glioblastoma patients with further prospective validation.

Long noncoding RNAs: emerging regulators of tumor angiogenesis

Long noncoding RNAs (lncRNAs) participate in multiple biological processes especially human diseases, of which, tumor seems to be one of the most significant. Angiogenesis has been deemed to have a pivotal role in a series of tumor biological behaviors in tumorigenesis, progression and prognosis. Emerging evidences suggested that lncRNAs are involved in tumor angiogenesis and lncRNAs have already been verified to be potential biomarkers and promising therapeutic targets. This review summarized emerging angiogenesis-related lncRNAs, discussed their mechanisms interacting with cytokines, cancer stem cells, miRNAs and tumor hypoxia microenvironment, and demonstrated if lncRNAs could be new candidate targets of antiangiogenesis therapy.

Genome-wide identification of lncRNAs associated with chlorantraniliprole resistance in diamondback moth Plutella xylostella (L.)

BACKGROUND

Long noncoding RNAs (lncRNAs) are now considered important regulatory factors, with a variety of biological functions in many species including insects. Some lncRNAs have the ability to show rapid responses to diverse stimuli or stress factors and are involved in responses to insecticide. However, there are no reports to date on the characterization of lncRNAs associated with chlorantraniliprole resistance in Plutella xylostella.

RESULTS

Nine RNA libraries constructed from one susceptible (CHS) and two chlorantraniliprole-resistant P. xylostella strains (CHR, ZZ) were sequenced, and 1309 lncRNAs were identified, including 877 intergenic lncRNAs, 190 intronic lncRNAs, 76 anti-sense lncRNAs and 166 sense-overlapping lncRNAs. Of the identified lncRNAs, 1059 were novel. Furthermore, we found that 64 lncRNAs were differentially expressed between CHR and CHS and 83 were differentially expressed between ZZ and CHS, of which 22 were differentially expressed in both CHR and ZZ. Most of the differentially expressed lncRNAs were hypothesized to be associated with chlorantraniliprole resistance in P. xylostella. The targets of lncRNAs via cis- (<10 kb upstream and downstream) or trans- (Pearson's correlation, r > 0.9 or < -0.9, P < 0.05) regulatory effects were also identified; many of the differently expressed lncRNAs were correlated with various important protein-coding genes involved in insecticide resistance, such as the ryanodine receptor, uridine diphosphate glucuronosyltransferase (UGTs), cytochrome P450, esterase and the ATP-binding cassette transporter.

CONCLUSIONS

Our results represent the first global identification of lncRNAs associated with chlorantraniliprole resistance in P. xylostella. These results will facilitate future studies of the regulatory mechanisms of lncRNAs in chlorantraniliprole and other insecticide resistance and in other biological processes in P. xylostella.

Systematic identification and characterization of cardiac long intergenic noncoding RNAs in zebrafish

Long intergenic noncoding RNAs (lincRNAs) are increasingly recognized as potential key regulators of heart development and related diseases, but their identities and functions remain elusive. In this study, we sought to identify and characterize the cardiac lincRNA transcriptome in the experimentally accessible zebrafish model by integrating bioinformatics analysis with experimental validation. By conducting genome-wide RNA sequencing profiling of zebrafish embryonic hearts, adult hearts, and adult muscle, we generated a high-confidence set of 813 cardiac lincRNA transcripts, 423 of which are novel. Among these lincRNAs, 564 are expressed in the embryonic heart, and 730 are expressed in the adult heart, including 2 novel lincRNAs, TCONS_00000891 and TCONS_00028686, which exhibit cardiac-enriched expression patterns in adult heart. Using a method similar to a fetal gene program, we identified 51 lincRNAs with differential expression patterns between embryonic and adult hearts, among which TCONS_00009015 responded to doxorubicin-induced cardiac stress. In summary, our genome-wide systematic identification and characterization of cardiac lincRNAs lays the foundation for future studies in this vertebrate model to elucidate crucial roles for cardiac lincRNAs during heart development and cardiac diseases.

Emerging roles of long non-coding RNAs in plant response to biotic and abiotic stresses

Spectacular progress in high-throughput transcriptome sequencing and expression profiling using next-generation sequencing technologies have recently revolutionized molecular biology and allowed massive advances in identifying the genomic regions and molecular mechanisms underlying transcriptional regulation of growth, development, and stress response. Through recent research, non-coding RNAs, in particular long non-coding RNAs, have emerged as key regulators of transcription in eukaryotes. Long non-coding RNAs are vastly heterogeneous groups of RNAs that execute a broad range of essential roles in various biological processes at the epigenetic, transcriptional, and post-transcriptional levels. They modulate transcription through diverse mechanisms. Recently, numerous lncRNAs have been identified to be associated with defense responses to biotic and abiotic stresses. These have been suggested to perform indispensable roles in plant immunity and adaptation to environmental conditions. However, only a few lncRNAs have been functionally characterized in plants. In this paper, we summarize the present knowledge of lncRNAs, review the recent advances in understanding regulatory functions of lncRNAs, and highlight the emerging roles of lncRNAs in regulating immune responses in plants.

Identification of long non-coding transcripts with feature selection: a comparative study

Background

The unveiling of long non-coding RNAs as important gene regulators in many biological contexts has increased the demand for efficient and robust computational methods to identify novel long non-coding RNAs from transcripts assembled with high throughput RNA-seq data. Several classes of sequence-based features have been proposed to distinguish between coding and non-coding transcripts. Among them, open reading frame, conservation scores, nucleotide arrangements, and RNA secondary structure have been used with success in literature to recognize intergenic long non-coding RNAs, a particular subclass of non-coding RNAs.

Results

In this paper we perform a systematic assessment of a wide collection of features extracted from sequence data. We use most of the features proposed in the literature, and we include, as a novel set of features, the occurrence of repeats contained in transposable elements. The aim is to detect signatures (groups of features) able to distinguish long non-coding transcripts from other classes, both protein-coding and non-coding. We evaluate different feature selection algorithms, test for signature stability, and evaluate the prediction ability of a signature with a machine learning algorithm. The study reveals different signatures in human, mouse, and zebrafish, highlighting that some features are shared among species, while others tend to be species-specific. Compared to coding potential tools and similar supervised approaches, including novel signatures, such as those identified here, in a machine learning algorithm improves the prediction performance, in terms of area under precision and recall curve, by 1 to 24%, depending on the species and on the signature.

Conclusions

Understanding which features are best suited for the prediction of long non-coding RNAs allows for the development of more effective automatic annotation pipelines especially relevant for poorly annotated genomes, such as zebrafish. We provide a web tool that recognizes novel long non-coding RNAs with the obtained signatures from fasta and gtf formats. The tool is available at the following url: http://www.bioinformatics-sannio.org/software/.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-017-1594-z) contains supplementary material, which is available to authorized users.

Vesiculated Long Non-Coding RNAs: Offshore Packages Deciphering Trans-Regulation between Cells, Cancer Progression and Resistance to Therapies

Extracellular vesicles (EVs) are nanosized vesicles secreted from virtually all cell types and are thought to transport proteins, lipids and nucleic acids including non-coding RNAs (ncRNAs) between cells. Since, ncRNAs are central to transcriptional regulation during developmental processes; eukaryotes might have evolved novel means of post-transcriptional regulation by trans-locating ncRNAs between cells. EV-mediated transportation of regulatory elements provides a novel source of trans-regulation between cells. In the last decade, studies were mainly focused on microRNAs; however, functions of long ncRNA (lncRNA) have been much less studied. Here, we review the regulatory roles of EV-linked ncRNAs, placing a particular focus on lncRNAs, how they can foster dictated patterns of trans-regulation in recipient cells. This refers to envisaging novel mechanisms of epigenetic regulation, cellular reprogramming and genomic instability elicited in recipient cells, ultimately permitting the generation of cancer initiating cell phenotypes, senescence and resistance to chemotherapies. Conversely, such trans-regulation may introduce RNA interference in recipient cancer cells causing the suppression of oncogenes and anti-apoptotic proteins; thus favoring tumor inhibition. Collectively, understanding these mechanisms could be of great value to EV-based RNA therapeutics achieved through gene manipulation within cancer cells, whereas the ncRNA content of EVs from cancer patients could serve as non-invasive source of diagnostic biomarkers and prognostic indicators in response to therapies.

Identification of long noncoding RNAs for the detection of early stage lung squamous cell carcinoma by microarray analysis

The aberrant expressions of long noncoding RNAs have been reported in numerous cancers, which have facilitated the cancer diagnosis. However, the expression profile of lncRNAs in early stage lung squamous cell carcinoma has not been well discussed. The present study aimed to examine the expression profile of lncRNAs in early stage lung squamous cell carcinoma and identify lncRNA biomarkers for diagnosis. Through high-throughput lncRNA microarray, we screened thousands of aberrantly expressed lncRNAs and mRNAs in early stage lung squamous cell carcinoma tissues compared to their corresponding adjacent nontumorous tissues. Bioinformatics analyses were used to investigate the functions of aberrantly expressed mRNAs and their associated lncRNAs. After that, in order to identify lncRNA biomarkers for early detection, candidate lncRNA biomarkers were selected based on our established filtering pipeline and validated by real-time quantitative polymerase chain reaction on a total of 63 pairs of tumor samples. Five lncRNAs were finally identified which were able to distinguish early stage tumor and normal samples with high sensitivity (92%) and specificity (83%). These results imply that lncRNAs may be powerful biomarker for early diagnosis.

Long noncoding RNAs (lncRNAs) in triple negative breast cancer

Long noncoding RNAs (lncRNAs) are dysregulated in many cancer types, which are believed to play crucial roles in regulating several hallmarks of cancer biology. Triple Negative Breast Cancer (TNBC) is a very aggressive subtype of normal breast cancer, which has features of negativity for ER, PR, and HER2. Great efforts have been made to identify an association between lncRNAs expression profiles and TNBC, and to understand the functional role and molecular mechanism on aberrant-expressed lncRNAs. In this review, we summarized the existed knowledge on the systematics, biology, and function of lncRNAs. The advances from the most recent studies of lncRNAs in the predicament of breast cancer, TNBC, are highlighted, especially the functions of specifically selected lncRNAs. We also discussed the potential value of these lncRNAs in TNBC, providing clues for the diagnosis and treatments of TNBC.

The link between long noncoding RNAs and depression

The major depressive disorder (MDD) is a relatively common mental disorder from which that hundreds of million people have suffered, leading to displeasing life quality, which is characterized by health damage and even suicidal thoughts. The complicated development and functioning of MDD is still under exploration. Long noncoding RNA (lncRNAs) are highly expressed in the brain, could affect neural stem cell maintenance, neurogenesis and gliogenesis, brain patterning, synaptic and stress responses, and neural plasticity. The dysregulation of certain lncRNAs induces in neurodevelopmental, neurodegenerative and neuroimmunological disorders, primary brain tumors, and psychiatric diseases. Although advances have been made, no fully satisfactory treatments for major depression are available, further investigation is requested. And recently data showed that the expression level of the majority of lncRNAs demonstrated a clear tendency of upregulation, and the certain dysregulated miRNAs and lncRNAs in the MDD have been proved to have a co-synergism mechanism, that is why we speculate lncRNA might get the capability to regulate MDD. Few identified lncRNAs have been deeply studied in detailed experiments up until now, little predictions of their function have been raised, and further researches is calling for discover their signal pathway and related regulatory networks.

Chronic Sleep Restriction Induces Cognitive Deficits and Cortical Beta-Amyloid Deposition in Mice via BACE1-Antisense Activation

AIMS

To clarify the correlation between chronic sleep restriction (CSR) and sporadic Alzheimer disease (AD), we determined in wild-type mice the impact of CSR, on cognitive performance, beta-amyloid (Aβ) peptides, and its feed-forward regulators regarding AD pathogenesis.

METHODS

Sixteen nine-month-old C57BL/6 male mice were equally divided into the CSR and control groups. CSR was achieved by application of a slowly rotating drum for 2 months. The Morris water maze test was used to assess cognitive impairment. The concentrations of Aβ peptides, amyloid precursor protein (APP) and β-secretase 1 (BACE1), and the mRNA levels of BACE1 and BACE1-antisense (BACE1-AS) were measured.

RESULTS

Following CSR, impairments of spatial learning and memory consolidation were observed in the mice, accompanied by Aβ plaque deposition and an increased Aβ concentration in the prefrontal and temporal lobe cortex. CSR also upregulated the β-secretase-induced cleavage of APP by increasing the protein and mRNA levels of BACE1, particularly the BACE1-AS.

CONCLUSIONS

This study shows that a CSR accelerates AD pathogenesis in wild-type mice. An upregulation of the BACE1 pathway appears to participate in both cortical Aβ plaque deposition and memory impairment caused by CSR. BACE1-AS is likely activated to initiate a cascade of events that lead to AD pathogenesis. Our study provides, therefore, a molecular mechanism that links CSR to sporadic AD.

Expression profile of lncRNA in human bronchial epithelial cells response to Talaromyces marneffei infection: A microarray analysis

Talaromyces marneffei is an important opportunistic pathogenic fungus capable of causing systemic lethal infection through inhalation of its conidia. However, little is known about the pathogenesis and interactions between Talaromyces marneffei and host. The aim of this study was to identify potential long noncoding RNAs (lncRNAs) and coding genes associated with interactions between airway epithelial cell and Talaromyces marneffei conidia. We carried out a microarray analysis to determine the expression profile of lncRNA and mRNA in human bronchial epithelial cell in response to Talaromyces marneffei infection. Compared to control group, we found that 370 and 149 lncRNAs were up and down regulated, respectively. Meanwhile, the expression level of 269 and 60 mRNAs was increased and decreased, respectively. To understand the potential role of the differentially expressed lncRNAs, we performed functional annotations of the corresponding coding genes using gene ontology and pathway analyses. Our results provide insights into the pathogenesis of early infection by Talaromyces marneffei.

Identifying and functionally characterizing tissue-specific and ubiquitously expressed human lncRNAs

Recent advances in transcriptome sequencing have made it possible to distinguish ubiquitously expressed long non-coding RNAs (UE lncRNAs) from tissue-specific lncRNAs (TS lncRNAs), thereby providing clues to their cellular functions. Here, we assembled and functionally characterized a consensus lncRNA transcriptome by curating hundreds of RNA-seq datasets across normal human tissues from 16 independent studies. In total, 1,184 UE and 2,583 TS lncRNAs were identified. These different lncRNA populations had several distinct features. Specifically, UE lncRNAs were associated with genomic compaction and highly conserved exons and promoter regions. We found that UE lncRNAs are regulated at the transcriptional level (with especially strong regulation of enhancers) and are associated with epigenetic modifications and post-transcriptional regulation. Based on these observations we propose a novel way to predict the functions of UE and TS lncRNAs through analysis of their genomic location and similarities in epigenetic modifications. Our characterization of UE and TS lncRNAs may provide a foundation for lncRNA genomics and the delineation of complex disease mechanisms.

Long noncoding RNAs in the p53 network

The tumor-suppressor protein p53 is activated in response to numerous cellular stresses including DNA damage. p53 functions primarily as a sequence-specific transcription factor that controls the expression of hundreds of protein-coding genes and noncoding RNAs, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs). While the role of protein-coding genes and miRNAs in mediating the effects of p53 has been extensively studied, the physiological function and molecular mechanisms by which p53-regulated lncRNAs act is beginning to be understood. In this review, we discuss recent studies on lncRNAs that are directly or indirectly regulated by p53 and how they contribute to the biological outcomes of p53 activation. WIREs RNA 2017, 8:e1410. doi: 10.1002/wrna.1410 For further resources related to this article, please visit the WIREs website.

A molecular conundrum involving hypothalamic responses to and roles of long non-coding RNAs following food deprivation

Long non-coding RNAs (lncRNAs) are one of most poorly understood RNA classes in the mammalian transcriptome. However, they are emerging as important players in transcriptional regulation, especially within the complexity of the nervous system. This review summarizes the known information about lncRNAs, and their roles in endocrine processes, as well as the lesser-known information about lncRNAs in the brain, and in the neuroendocrine hypothalamus. A "call-to-action" is presented for researchers to use archival transcriptome data to characterize differentially expressed lncRNA species within the hypothalamus. In accordance, we analyze for differential-expression of lncRNA between normal mice and mice with a targeted deletion of the nescient helix-loop-helix 2 gene, and between C57Bl/6 and 129Sv/J mice. Finally, strategies and approaches for researchers to analyze their own datasets or those on the NCBI GEO datasets repository are provided, in hopes that future studies will reveal many new roles for lncRNAs in hypothalamic physiological responses, solving this so-called "molecular conundrum" once and for all.

Long noncoding RNAs in osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis that may affect all joint tissues. Unfortunately, the pathogenesis of OA is not fully understood yet and it cannot be cured totally. Long noncoding RNA (lncRNA) is a type of RNA molecule greater than 200 nucleotides, and deregulated expression of lncRNAs plays an important role in many types of inflammation-related diseases. In this review, we have focused on the association of lncRNAs in the development and progression of OA and the possibility of lncRNAs as a therapeutic agent for the treatment of OA. Some lncRNAs are up-regulated in OA cartilage, and plays a critical role in the degradation of chondrocyte extracellular matrix, consequently weakening the integrity of the articular cartilage. Therapeutic targeting of these lncRNAs has shown significant influence on controlling OA progression. More clinical studies are in focus for OA treatment strategy by targeting lncRNAs.

Long non-coding RNAs (lncRNAs) in skeletal and cardiac muscle: potential therapeutic and diagnostic targets?

The recent discovery that thousands of RNAs are transcribed by the cell but are never translated into protein, highlights a significant void in our current understanding of how transcriptional networks regulate cellular function. This is particularly astounding when we consider that over 75% of the human genome is transcribed into RNA, but only approximately 2% of RNA is translated into known proteins. This raises the question as to what function the other so-called ‘non-coding RNAs’ (ncRNAs) are performing in the cell. Over the last decade, an enormous amount of research has identified several classes of ncRNAs, predominantly short ncRNAs (<200 nt) that have been confirmed to have functional significance. Recent advances in sequencing technology and bioinformatics have also allowed for the identification of a novel class of ncRNAs, termed long ncRNA (lncRNA) (>200 nt). Several studies have recently shown that long non-coding RNAs (lncRNAs) are associated with tissue development and disease, particularly in cell types that undergo differentiation such as stem cells, cancer cells and striated muscle (skeletal/cardiac). Therefore, understanding the function of these lncRNAs and designing strategies to detect and manipulate them, may present novel therapeutic and diagnostic opportunities. This review will explore the current literature on lncRNAs in skeletal and cardiac muscle and discuss their recent implication in development and disease. Lastly, we will also explore the possibility of using lncRNAs as therapeutic and diagnostic tools and discuss the opportunities and potential shortcomings to these applications.

Predicting the Organelle Location of Noncoding RNAs Using Pseudo Nucleotide Compositions

Noncoding RNAs (ncRNAs) are implicated in various biological processes. Recent findings have demonstrated that the function of ncRNAs correlates with their provenance. Therefore, the recognition of ncRNAs from different organelle genomes will be helpful to understand their molecular functions. However, the weakness of experimental techniques limits the progress toward studying organellar ncRNAs and their functional relevance. As a complement of experiments, computational method provides an important choice to identify ncRNA in different organelles. Thus, a computational model was developed to identify ncRNAs from kinetoplast and mitochondrion organelle genomes. In this model, RNA sequences are encoded by "pseudo dinucleotide composition." It was observed by the jackknife test that the overall success rate achieved by the proposed model was 90.08 %. We hope that the proposed method will be helpful in predicting ncRNA organellar locations.