lncRNAs In Development Research Articles

A desert lncRNA HIDEN regulates human endoderm differentiation via interacting with IMP1 and stabilizing FZD5 mRNA

BackgroundExtensive studies have revealed the function and mechanism of lncRNAs in development and differentiation, but the majority have focused on those lncRNAs adjacent to protein-coding genes. In contrast, lncRNAs located in gene deserts are rarely explored. Here, we utilize multiple differentiation systems to dissect the role of a desert lncRNA, HIDEN (human IMP1-associated "desert" definitive endoderm lncRNA), in definitive endoderm differentiation from human pluripotent stem cells.ResultsWe show that desert lncRNAs are highly expressed with cell-stage-specific patterns and conserved subcellular localization during stem cell differentiation. We then focus on the desert lncRNA HIDEN which is upregulated and plays a vital role during human endoderm differentiation. We find depletion of HIDEN by either shRNA or promoter deletion significantly impairs human endoderm differentiation. HIDEN functionally interacts with RNA-binding protein IMP1 (IGF2BP1), which is also required for endoderm differentiation. Loss of HIDEN or IMP1 results in reduced WNT activity, and WNT agonist rescues endoderm differentiation deficiency caused by the depletion of HIDEN or IMP1. Moreover, HIDEN depletion reduces the interaction between IMP1 protein and FZD5 mRNA and causes the destabilization of FZD5 mRNA, which is a WNT receptor and necessary for definitive endoderm differentiation.ConclusionsThese data suggest that desert lncRNA HIDEN facilitates the interaction between IMP1 and FZD5 mRNA, stabilizing FZD5 mRNA which activates WNT signaling and promotes human definitive endoderm differentiation.

Long non-coding RNAs: definitions, functions, challenges and recommendations.

Genes specifying long non-coding RNAs (lncRNAs) occupy a large fraction of the genomes of complex organisms. The term 'lncRNAs' encompasses RNA polymeraseI (Pol I), PolII andPolIII transcribed RNAs, and RNAs from processed introns. The various functions of lncRNAs and their many isoforms and interleaved relationships with other genes make lncRNA classification and annotation difficult. Most lncRNAs evolve more rapidly than protein-coding sequences, are cell type specific and regulate many aspects of cell differentiation and development and other physiological processes. Many lncRNAs associate with chromatin-modifying complexes, are transcribed from enhancers and nucleate phase separation of nuclear condensates and domains, indicating an intimate link between lncRNA expression and the spatial control of gene expression during development. lncRNAs also have important roles in the cytoplasm and beyond, including in the regulation of translation, metabolism and signalling. lncRNAs often have a modular structure and are rich in repeats, which are increasingly being shown to be relevant to their function. In this Consensus Statement, we address the definition and nomenclature of lncRNAs and their conservation, expression, phenotypic visibility, structure and functions. We also discuss research challenges and provide recommendations to advance the understanding of the roles of lncRNAs in development, cell biology and disease.

The role of lncRNAs in regulation of DKD and diabetes-related cancer.

Diabetes mellitus often results in several complications, such as diabetic kidney disease (DKD) and end-stage renal diseases (ESRDs). Cancer patients often have the dysregulated glucose metabolism. Abnormal glucose metabolism can enhance the tumor malignant progression. Recently, lncRNAs have been reported to regulate the key proteins and signaling pathways in DKD development and progression and in cancer patients with diabetes. In this review article, we elaborate the evidence to support the function of lncRNAs in development of DKD and diabetes-associated cancer. Moreover, we envisage that lncRNAs could be diagnosis and prognosis biomarkers for DKD and cancer patients with diabetes. Furthermore, we delineated that targeting lncRNAs might be an alternative approach for treating DKD and cancer with dysregulated glucose metabolism.

Comprehensive Analysis of the Expression Profiles of Hepatic lncRNAs in the Mouse Model of Alcoholic Liver Disease.

Background and Aim: The worldwide prevalence of alcoholic liver disease (ALD) due to escalating alcohol consumption has presented an unprecedented pressure on human health. A few studies have determined long non-coding RNAs (lncRNAs) involved in the pathogenesis of liver diseases. However, the roles of lncRNAs in ALD development is still poorly understood.Methods: An ALD mouse model was established and confirmed. Expression profiles of lncRNAs were obtained by whole transcriptome sequencing. The altered lncRNAs in ALD mice were further verified by qRT-PCR. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to enrich the functions of these lncRNAs. In combination with miRNA and mRNA profiles, we constructed concise endogenous RNA (ceRNA) networks. The function of the most up/downregulated lnRNA was further verified and investigated in both ALD model and AML-12 cells.Results: Totally, five downregulated lncRNAs were obtained and verified in ALD mice. The GO term and KEGG pathway analyses revealed that the identified lncRNAs were associated with alcohol-induced hepatic oxidative damage, cellular inflammation, and lipid metabolism. Combination the differentially modulated miRNAs and mRNAs with ceRNA network analysis, we constructed five ceRNA networks and obtained 30 miRNAs and 25 mRNAs that may participate in ALD. Further, we verified and investigate the function of the most downregulated lnc_1700023H06Rik. Depletion lnc_1700023H06Rik reduced genes encoding for lipid metabolism, especially mRNA Acat2 (ENSMUST00000159697) and Pgrmc2 (ENSMUST00000058578) both in vivo and in vitro. Knocking down lnc_1700023H06Rik induced triglyceride accumulation and lactate dehydrogenase leakage in AML12 cells, consisting with that in alcohol-treated cells.Conclusion: The five remarkably downregulated lncRNAs in ALD mouse model were identified as novel biomarkers, highlighting the key role of lncRNAs in the development of ALD. The effect of lnc_1700023H06Rik plays a pivotal role in lipid deposition and its pathological pathway in ALD needs further investigation.

Plasmacytoma variant translocation 1 and nicotinamide phosphoribosyl-transferase long noncoding RNAs promote colorectal cancer

The prevalence of colorectal cancer (CRC) is increasing worldwide. Identifying the mechanisms that cause tumors, and the role of long non-coding RNAs (LncRNAs) in this respect have received much attention in the recent years. This study sought to identify the role of plasmacytoma variant translocation 1 (PVT1) and nicotinamide phosphoribosyltransferase (NAMPT) LncRNAs in development of CRC.The tumoral tissue required to study the expression of PVT1 and NAMPT LncRNAs was obtained from the tumor bank of Imam Khomeini Hospital in Tehran and normal adjacent tissues served as controls. The clinicopathological features of the tumors were recorded, and RNA extraction and cDNA synthesis were performed using the corresponding kits. The reverse-transcription polymerase chain reaction (RT-PCR) was performed using specific PVT1 and NAMPT primers. SPSS version 22 was used to analyze the data.The results showed higher expression of PVT1 and NAMPT LncRNAs in CRC specimens compared with control samples. High expression of PVT1 gene was observed in high-grade tumors. Higher expression of NAMPT was seen when extracapsular nodal extension was absent. Overall survival rate was reduced with higher expression level of NAMPT and PVT1 LncRNAs.The results of the present study revealed the significant role of PVT1 and NAMPT LncRNAs in CRC. However, more research is required to confirm this finding.

LncRNAs in development and differentiation: from sequence motifs to functional characterization

The number of long noncoding RNAs (lncRNAs) with characterized developmental and cellular functions continues to increase, but our understanding of the molecular mechanisms underlying lncRNA functions, and how they are dictated by RNA sequences, remains limited. Relatively short, conserved sequence motifs embedded in lncRNA transcripts are often important determinants of lncRNA localization, stability and interactions. Identifying such RNA motifs remains challenging due to the substantial length of lncRNA transcripts and the rapid evolutionary turnover of lncRNA sequences. Nevertheless, the recent discovery of specific RNA elements, together with their experimental interrogation, has enabled the first step in classifying heterogeneous lncRNAs into sub-groups with similar molecular mechanisms and functions. In this Review, we focus on lncRNAs with roles in development, cell differentiation and normal physiology in vertebrates, and we discuss the sequence elements defining their functions. We also summarize progress on the discovery of regulatory RNA sequence elements, as well as their molecular functions and interaction partners.

Bioinformatics analysis on lncRNA and mRNA expression profiles for novel biological features of valvular heart disease with atrial fibrillation

The biological features of the valvular heart disease with atrial fibrillation (AF-VHD) remain unknown when involving long non-coding RNAs (lncRNAs). This study performed system analysis on lncRNA and messenger RNA (mRNA) expression profiles constructed by using bioinformatics methods and tools for biological features of AF-VHD. Fold change and t-test were used to identify differentially expressed (DE) lncRNAs and mRNAs. The enrichment analysis of DE mRNAs was performed. The subgroups formed by lncRNAs and nearby mRNAs were screened, and a transcriptional regulation network among lncRNAs, mRNAs, and transcription factors (TFs) was constructed. The interactions between mRNAs related to lncRNAs and drugs were predicted. The 620 AF-VHD-related DE lncRNAs and 452 DE mRNAs were identified. The 3 lncRNA subgroups were screened. The 665 regulations mediated by lncRNAs and TFs were identified. The 9 mRNAs related to lncRNAs had 1 or more potential drug interactions, totaling 37 drugs. Of these, 9 drugs targeting 3 genes are already known to be able to control or trigger atrial fibrillation (AF) or other cardiac arrhythmias. The found biological features of AF-VHD provide foundations for further biological experiments to better understand the roles of lncRNAs in development from the valvular heart disease (VHD) to AF-VHD.

Long Non-Coding RNAs Emerging as Potential Epigenetic Biomarkers for Tobacco and/or Alcohol-Induced Head and Neck Cancer

Head and Neck cancer (HNC) is one of the most prevalent and lethal cancer globally. The incidence of tobacco-induced HNC is gradually increasing in low and middle income countries. Among the various causative factors associated with HNCs, tobacco and alcohol play synergistic effect and are frequently associated with the risk of HNC. Tobacco-induced HNCs show distinct genetic and epigenetic alterations leading to different clinical outcomes in comparison to HPV-infected HNCs. Tobacco-induced HNCs are often associated with tumor aggressiveness, poor prognosis and low or nil prevalence of HPV infection. Apart from carcinogenic effects of these causative factors (use of tobacco products, alcohol intake and HPV or EBV infections), recent studies show that exposure to these factors alter/disrupt the regulation of non-coding RNAs including the long non-coding RNAs (lncRNAs). Altered lncRNA regulation is brought about by signalling networks that regulate cellular differentiation, apoptosis, angiogenesis and inflammatory pathways which play key functions in the genesis of different cancers including HNCs. There are numbers of studies supporting the emerging role of lncRNAs in development of HNC; however, reports connecting lncRNAs expression and addiction habits in HNC are still preliminary and sparse. Therefore, identification and characterization of lncRNAs that are differentially expressed upon exposure to risk-factors can serve as unique therapeutic targets and potential biomarker(s) for effective treatment of HNC subtypes. In this short review, we briefly reviewed the emerging role of lncRNAs in tobacco and alcohol induced HNCs.

Platforms for Investigating LncRNA Functions.

Prior to the sequencing of the human genome, it was presumed that most of the DNA coded for proteins. However, with the advent of next-generation sequencing, it has now been recognized that most complex eukaryotic genomes are in fact transcribed into noncoding RNAs (ncRNAs), including a family of transcripts referred to as long noncoding RNAs (lncRNAs). LncRNAs have been implicated in many biological processes ranging from housekeeping functions such as transcription to more specialized functions such as dosage compensation or genomic imprinting, among others. Interestingly, lncRNAs are not limited to a defined set of functions but can regulate varied activities such as messenger RNA degradation, translation, and protein kinetics or function as RNA decoys or scaffolds. Although still in its infancy, research into the biology of lncRNAs has demonstrated the importance of lncRNAs in development and disease. However, the specific mechanisms through which these lncRNAs act remain poorly defined. Focused research into a small number of these lncRNAs has provided important clues into the heterogeneous nature of this family of ncRNAs. Due to the complex diversity of lncRNA function, in this review, we provide an update on the platforms available for investigators to aid in the identification of lncRNA function.

LncRNAs in development and disease: from functions to mechanisms.

Differential expression of long non-coding RNAs (lncRNAs) during differentiation and their misregulation in cancer highlight their potential as cell fate regulators. While some example lncRNAs have been characterized in great detail, the functional in vivo relevance of others has been called into question. Finding functional lncRNAs will most probably require a combination of complementary approaches that will greatly vary depending on their mode of action. In this review, we discuss the different tools available to dissect genetically lncRNA requirements and how each is best suited to studies in particular contexts. Moreover, we review different strategies used to select candidate lncRNAs and give an overview of lncRNAs described to regulate development and cancer through different mechanisms.

Understanding the Role of lncRNAs in Nervous System Development.

The diversity of lncRNAs has expanded within mammals in tandem with the evolution of increased brain complexity, suggesting that lncRNAs play an integral role in this process. In this chapter, we will highlight the identification and characterization of lncRNAs in nervous system development. We discuss the potential role of lncRNAs in nervous system and brain evolution, along with efforts to create comprehensive catalogues that analyze spatial and temporal changes in lncRNA expression during nervous system development. Additionally, we focus on recent endeavors that attempt to assign function to lncRNAs during nervous system development. We highlight discrepancies that have been observed between invitro and invivo studies of lncRNA function and the challenges facing researchers in conducting mechanistic analyses of lncRNAs in the developing nervous system. Altogether, this chapter highlights the emerging role of lncRNAs in the developing brain and sheds light on novel, RNA-mediated mechanisms by which nervous system development is controlled.

Long Noncoding RNA Expression during Human B-Cell Development.

Long noncoding RNAs (lncRNAs) have emerged as important regulators of diverse cellular processes, but their roles in the developing immune system are poorly understood. In this study, we analysed lncRNA expression during human B-cell development by array-based expression profiling of eleven distinct flow-sorted B-cell subsets, comprising pre-B1, pre-B2, immature, naive, memory, and plasma cells from bone marrow biopsies (n = 7), and naive, centroblast, centrocyte, memory, and plasmablast cells from tonsil tissue samples (n = 6), respectively. A remapping strategy was used to assign the array probes to 37630 gene-level probe sets, reflecting recent updates in genomic and transcriptomic databases, which enabled expression profiling of 19579 long noncoding RNAs, comprising 3947 antisense RNAs, 5277 lincRNAs, 7625 pseudogenes, and 2730 additional lncRNAs. As a first step towards inferring the functions of the identified lncRNAs in developing B-cells, we analysed their co-expression with well-characterized protein-coding genes, a method known as “guilt by association”. By using weighted gene co-expression network analysis, we identified 272 lincRNAs, 471 antisense RNAs, 376 pseudogene RNAs, and 64 lncRNAs within seven sub-networks associated with distinct stages of B-cell development, such as early B-cell development, B-cell proliferation, affinity maturation of antibody, and terminal differentiation. These data provide an important resource for future studies on the functions of lncRNAs in development of the adaptive immune response, and the pathogenesis of B-cell malignancies that originate from distinct B-cell subpopulations.

Involvement of lncRNA dysregulation in gastric cancer.

Benefiting from the fast development of sequencing technique and bioinformatics methods, more and more new long non-coding RNAs (lncRNAs) are discovered and identified. lncRNAs were firstly thought to be transcription noise that from genome desert without biological function; however, as the discovery of lncRNA XIST and HOTAIR uncovers the emerging roles of lncRNAs in development and tumorigenesis. In the past decades, accumulating evidence have indicated that lncRNAs involve in a wide range of biological functions, such as X-chromosome inactivation, reprogramming stem cell pluripotency, regulation of the immune response and carcinogenesis. Although lots of studies have demonstrated that dysregulation of lncRNAs involve in diverse diseases including cancers, the underlying molecular mechanisms of lncRNAs are not well documented. Interestingly, our previous studies and others' have shown that numerous of lncRNAs expression was misregulated in gastric cancer. In this review, we will focus on the dysregulated lncRNAs and their biological function and underlying pathways or mechanisms in GC. Finally, we will discuss the potential roles of lncRNAs acting as biomarkers or therapeutic targets in GC patients.

BRAF-Activated Long Noncoding RNA Modulates Papillary Thyroid Carcinoma Cell Proliferation through Regulating Thyroid Stimulating Hormone Receptor.

PurposeThe importance of long noncoding RNAs (lncRNAs) in tumorigenesis has recently been demonstrated. However, the role of lncRNAs in development of thyroid cancer remains largely unknown.Materials and MethodsUsing quantitative reverse transcription polymerase chain reaction, expression of three lncRNAs, including BRAF-activated long noncoding RNA (BANCR), papillary thyroid cancer susceptibility candidate 3 (PTCSC3), and noncoding RNA associated with mitogen-activated protein kinase pathway and growth arrest (NAMA), was investigated in the current study.ResultsOf the three lncRNAs (BANCR, PTCSC3, and NAMA), expression of BANCR was significantly up-regulated while PTCSC3 and NAMA were significantly down-regulated in papillary thyroid carcinoma (PTC) compared to that in normal tissue. BANCR-knockdown in a PTC-derived cell line (IHH-4) resulted in significant suppression of thyroid stimulating hormone receptor (TSHR). BANCR-knockdown also led to inhibition of cell growth and cell cycle arrest at G0/G1 phase through down-regulation of cyclin D1. In addition, BANCR was enriched by polycomb enhancer of zeste homolog 2 (EZH2), and silencing BANCR led to decreased chromatin recruitment of EZH2, which resulted significantly reduced expression of TSHR.ConclusionThese findings indicate that BANCR may contribute to the tumorigenesis of PTC through regulation of cyclin D1 and TSHR.

Pseudogene-derived lncRNAs: emerging regulators of gene expression.

In the more than one decade since the completion of the Human Genome Project, the prevalence of non-protein-coding functional elements in the human genome has emerged as a key revelation in post-genomic biology. Highlighted by the ENCODE (Encyclopedia of DNA Elements) and FANTOM (Functional Annotation of Mammals) consortia, these elements include tens of thousands of pseudogenes, as well as comparably numerous long non-coding RNA (lncRNA) genes. Pseudogene transcription and function remain insufficiently understood. However, the field is of great importance for human disease due to the high sequence similarity between pseudogenes and their parental protein-coding genes, which generates the potential for sequence-specific regulation. Recent case studies have established essential and coordinated roles of both pseudogenes and lncRNAs in development and disease in metazoan systems, including functional impacts of lncRNA transcription at pseudogene loci on the regulation of the pseudogenes’ parental genes. This review synthesizes the nascent evidence for regulatory modalities jointly exerted by lncRNAs and pseudogenes in human disease, and for recent evolutionary origins of these systems.

Long noncoding RNAs in gene expression control

Studies have shown that most of the sequence in the mammalian genome is transcribed into long noncoding RNAs (lncRNAs). Their crucial roles in gene regulation are becoming a hotspot in current biomedical research. LncRNAs can control gene activities through multiple mechanisms such as: 1) direct or indirect regulation of gene expression via cis-/trans-action or function as protein baits in the nucleus; 2) affecting the stability and the translational process of mRNA; 3) functioning as competitors to regulation of microRNA; 4) binding to transcription factors. Recent studies have highlighted the significance of lncRNAs in development and diseases, and their potentials in future clinical application.

Long non-coding RNA-dependent transcriptional regulation in neuronal development and disease.

Comprehensive analysis of the mammalian transcriptome has revealed that long non-coding RNAs (lncRNAs) may make up a large fraction of cellular transcripts. Recent years have seen a surge of studies aimed at functionally characterizing the role of lncRNAs in development and disease. In this review, we discuss new findings implicating lncRNAs in controlling development of the central nervous system (CNS). The evolution of the higher vertebrate brain has been accompanied by an increase in the levels and complexities of lncRNAs expressed within the developing nervous system. Although a limited number of CNS-expressed lncRNAs are now known to modulate the activity of proteins important for neuronal differentiation, the function of the vast majority of neuronal-expressed lncRNAs is still unknown. Topics of intense current interest include the mechanism by which CNS-expressed lncRNAs might function in epigenetic and transcriptional regulation during neuronal development, and how gain and loss of function of individual lncRNAs contribute to neurological diseases.

Integration of Genome-wide Approaches Identifies lncRNAs of Adult Neural Stem Cells and Their Progeny In Vivo

Long noncoding RNAs (lncRNAs) have been described in cell lines and various whole tissues, but lncRNA analysis of development invivo is limited. Here, we comprehensively analyze lncRNA expression for the adult mouse subventricular zone neuralstem cell lineage. We utilize complementary genome-wide techniques including RNA-seq, RNA CaptureSeq, and ChIP-seq to associate specific lncRNAs with neural cell types, developmental processes, and human disease states. By integrating data from chromatin state maps, custom microarrays, and FACS purification of the subventricular zone lineage, we stringently identify lncRNAs with potential roles in adult neurogenesis. shRNA-mediated knockdown of two such lncRNAs, Six3os and Dlx1as, indicate roles for lncRNAs in the glial-neuronal lineage specification of multipotent adult stem cells. Our data and workflow thus provide a uniquely coherent invivo lncRNA analysis and form the foundation of a user-friendly online resource for the study of lncRNAs in development and disease.