Circular RNAs (circRNAs), a novel type of non-coding RNAs (ncRNAs), are ubiquitously expressed in eukaryotic cells during post-transcriptional processes. Unlike linear RNAs, circRNAs form covalent-closed continuous loops without 5' to 3' polarities and poly (A) tails. With advances in high-throughput sequencing technology, numerous circRNAs have been identified in plants, animals and humans. Notably, circRNAs display cell-type, tissue-type and developmental-stage specific expression patterns in eukaryotic transcriptome, which reveals their significant regulatory functions in gene expression. More importantly, circRNAs serve as microRNA (miRNA) sponges and crucial regulators of gene expression. Additionally, circRNAs modulate pre-mRNA alternative splicing and possess protein-coding capacity. CircRNAs exhibit altered expression under pathological conditions and are strongly associated with the development of various human diseases. Interestingly, circRNAs can also induce antiviral immune responses. A recent study found that the delivery of circRNAs generated in vitro activates RIG-I-mediated innate immune responses and provides protection against viral infection. The antiviral dsRNA-binding proteins, NF90/NF110, act as key regulators in circRNA biogenesis. NF90/NF110 are also functional in inhibiting viral replication through binding to viral mRNAs. In this review, we provide a comprehensive overview on the classification, biogenesis and functions of circRNAs. We also discuss the critical role of circRNAs in eliciting antiviral immunity, providing evidence for the potential implications of circRNAs in antiviral therapies.

/pdf/circular-rnas-a-novel-type-of-non-coding-rna-and-their-1xvx6a5po7.pdf

Circular RNAs: A novel type of non-coding RNA and their potential implications in antiviral immunity.

Non-coding RNAs (ncRNAs) are functional RNA molecules that are transcribed from DNA but not translated into proteins. ncRNAs function as key regulators of gene expression and chromatin modification. Recently, the functional role of ncRNAs in teleost fish has been extensively studied. Teleost fish are a highly diverse group among the vertebrate lineage. Fish are also important in terms of aquatic ecosystem, food production and human life, being the source of animal proteins worldwide and models of biomedical research. However, teleost fish always suffer from the invasion of infectious pathogens including viruses and bacteria, which has resulted in a tremendous economic loss to the fishing industry worldwide. Emerging evidence suggests that ncRNAs, especially miRNAs and lncRNAs, may serve as important regulators in cytokine and chemokine signaling, antigen presentation, complement and coagulation cascades, and T cell response in teleost fish. In this review, we summarize current knowledge and understanding of the roles of both miRNAs and lncRNAs in immune regulation in teleost fish. Molecular mechanism insights into the function of ncRNAs in fish immune response may contribute to the development of potential biomarkers and therapeutic targets for the prevention and treatment of fish diseases.

/pdf/non-coding-rnas-function-as-immune-regulators-in-teleost-1s2hev1h0k.pdf

Non-coding RNAs Function as Immune Regulators in Teleost Fish.

Circular RNAs (circRNAs) are a recently discovered class of noncoding RNAs found in many species across the eukaryotic kingdom. These intriguing RNA species are formed through a unique mechanism that is known as back splicing in which the 5' and 3' termini are covalently joined. Recent research has revealed that viruses also encode a repertoire of circRNAs. Some of these viral circRNAs are abundantly expressed and are reported to play a role in disease pathogenesis. A growing number of studies also indicate that host circRNAs are involved in immune responses against virus infections with either an antiviral or proviral role. In this review, we briefly introduce circRNA, its biogenesis, and mechanism of action. We go on to summarize the latest research on the expression, regulation, and functions of viral and host-encoded circRNAs during the host-virus interaction, with the aim of highlighting the potential of viral and host circRNAs as a suitable target for diagnostic biomarker development and therapeutic treatment of viral-associated diseases. We conclude by discussing the current limitations in knowledge and significance of elucidating the roles of circRNAs in host-virus interactions, as well as future directions for this emerging field.

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1111/febs.15639

Viruses join the circular RNA world.

Circular RNAs as a novel layer of regulatory mechanism in multiple sclerosis.

Olive flounder (Paralichthys olivaceus) is an important economical flatfish in Japan, Korea and China, but its production has been greatly threatened by disease outbreaks In this research, we aimed to explore the immune responsive mechanism of P olivaceus against Edwardsiella tarda infection by profiling the expression of circRNA, miRNA and mRNA by RNA-seq, and constructing a regulatory circular circRNA-miRNA-mRNA network Illumina sequencing of samples from normal control (H0), 2 h (H2), 8 h (H8) and 12 h (H12) post-challenge was conducted Differentially expressed (DE) circRNA (DE-circRNAs), miRNAs (DE-miRNAs), and mRNAs (DEGs) between challenge and control groups were identified, resulting a total of 62 DE-circRNAs, 39 DE-miRNAs and 3,011 DEGs Based on the differentially expressed gene results, miRNA-target interactions (circRNA-miR¬NA pairs and miRNA-mRNA pairs) were predicted by miRanda software Once these paired were combined, a preliminary circRNA-miRNA-mRNA network was generated with 198 circRNA-miRNA edges and 3,873 miRNA-mRNA edges, including 44 DE-circRNAs, 32 DE-miR¬NAs, and 1,774 DEGs KEGG analysis was performed to evaluate the function of the DEGs in this network, and we focused and identified two important intestinal immune pathways (Herpes simplex infection and Intestinal immune network for IgA production) that showed statistical significance between the challenge and control groups Furthermore, three critical DEGs (nectin2, MHC II α-chain and MHC II β-chain) were identified, mapped into the preliminary circRNA‑miRNA‑mRNA network and new circRNA-miRNA-mRNA regulatory networks were constructed In conclusion, we for the first time identified circRNA-miRNA-mRNA network from P olivaceus in the pathogenesis of E tarda, and provided valuable resources for further analyses of the molecular mechanisms and signaling networks

/pdf/identification-of-potential-immune-related-circrna-mirna-1wjccde99a.pdf

Identification of Potential Immune-Related circRNA-miRNA-mRNA Regulatory Network in Intestine of Paralichthys olivaceus During Edwardsiella tarda Infection.

Grass carp hemorrhagic disease, caused by the grass carp reovirus (GCRV), is a major disease that hampers the development of grass carp aquaculture in China. The mechanism underlying GCRV infection is still largely unknown. Circular RNAs (circRNAs) are important regulators involved in various biological processes. In the present study, grass carp were infected with GCRV, and spleen samples were collected at 0 (control), 1, 3, 5, and 7 days post-infection (dpi). Samples were used to construct and sequence circRNA libraries, and a total of 5052 circRNAs were identified before and after GCRV infection, of which 41 exhibited differential expression compared with controls. Many parental genes of the differentially expressed circRNAs are involved in metal ion binding, protein ubiquitination, enzyme activity, and nucleotide binding. Moreover, 72 binding miRNAs were predicted from the differentially expressed circRNAs, of which eight targeted genes were predicted to be involved in immune responses, blood coagulation, hemostasis, and complement and coagulation cascades. Upregulation of these genes may lead to endothelial and blood cell damage and hemorrhagic symptoms. Our results indicate that an mRNA–miRNA–circRNA network may be present in grass carp infected with GCRV, providing new insight into the mechanism underlying grass carp reovirus infection.

Deep Circular RNA Sequencing Provides Insights into the Mechanism Underlying Grass Carp Reovirus Infection.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

And Yaping Wang

Author Tools

Chat about Author

Papers

Deep Circular RNA Sequencing Provides Insights into the Mechanism Underlying Grass Carp Reovirus Infection.