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At least 19 recordsLinked to original sources

PubMed2024

Comprehensive analysis of circRNA-miRNA-mRNA network related to angiogenesis in recurrent implantation failure.

BACKGROUND: Abnormal endometrial blood flow causes a decrease in endometrial receptivity and is considered a relatively independent risk factor for recurrent implantation failure (RIF). This study aimed to explore the potentially functional circRNA-miRNA-mRNA network in RIF, and further explore its mechanism. METHODS: Datasets were downloaded from the GEO database to identify differentially expressed circRNAs, miRNAs and mRNAs. The circRNA-miRNA-mRNA and PPI networks were constructed using Cytoscape 3.6.0 and the STRING database, the hub genes were identified with the cytoHubba plug-in, and a circRNA-miRNA-hub mRNA regulatory sub-network was constructed. Then, GO and KEGG pathway enrichment analyses of the hub genes were performed to comprehensively analyze the mechanism of hub mRNAs in RIF. Due to the results of circRNAs-miRNAs-hub mRNAs regulatory network, we verified the expression of circRNA_0001721, circRNA_0000714, miR-17-5p, miR-29b-3p, HIF1A and VEGFA in the RIF mouse model by qRT‒PCR and western blotting. RESULTS: We initially identified 175 DEmRNAs, 48 DEmiRNAs and 56 DEcircRNAs in RIF associated with angiogenesis and constructed a circRNA-miRNA‒mRNA network and PPI network. We further identified six hub genes in the acquired network. Based on these genes, functional enrichment analysis revealed that the HIF-1 signaling pathway plays a vital role in endometrial angiogenesis in RIF. In addition, the interaction networks of circRNA_0001721/miR-17-5p/HIF1A and the circRNA_0000714/miR-29b-3p/VEGFA axis were predicted. In the RIF mouse model, circRNA_0001721, circRNA_0000714, HIF1A and VEGFA were down-regulated, whereas miR-17-5p and miR-29b-3p were up-regulated according to qRT‒PCR and western blotting. CONCLUSION: This study revealed that the HIF-1 signaling pathway plays a vital role in endometrial angiogenesis in RIF. The circRNA_0001721/miR-17-5p/HIF1A and circRNA_0000714/miR-29b-3p/VEGFA axes might play a role in the pathogenesis of endometrial angiogenesis in RIF.

MicroRNAs↗

PubMed2026

circASbase: A Comprehensive Database of Alternative Splicing Events in circRNAs.

Although extensive evidence has underscored the critical role of alternative splicing (AS) in generating mature circular RNA (circRNA) isoforms and augmenting their functional diversity, a significant gap remains in the availability of specialized databases housing circRNA AS events. To bridge this gap, we develop circASbase, a pioneering and comprehensive database that catalogs 452,129 AS events in 884,047 full-length circRNAs from 581 samples across 13 species, and provides rich annotations to facilitate understanding the splicing regulation of circRNA. Our findings reveal substantial differences between circRNAs and linear transcripts regarding the distribution and occurrence of AS events, highlighting the unique regulatory landscape of circRNAs. These special splicing events result in functional differences of circRNAs by affecting internal ribosome entry sites, N6-methyladenosine sites, open reading frames, protein features, microRNA targets, and more. In summary, circASbase not only meets the urgent need of the research community for data repositories, but also represents a significant advancement in our understanding of circRNA biology. With its user-friendly interfaces and web-based visualization tools, circASbase is poised to become an indispensable resource for researchers exploring the regulatory mechanisms and functional roles of AS events in circRNAs. This database will continuously drive new insights and discoveries in the field, setting the stage for further advancements in circRNA research. circASbase is freely available at http://reprod.njmu.edu.cn/cgi-bin/circASbase/.

Alternative Splicing↗

PubMed2026

CircRNA-based CD19-targeted CAR-NK therapy for B-cell acute lymphoblastic Leukemia using a Coccidioides immitis-derived group II intron platform.

Chimeric antigen receptor (CAR)-T cell therapy targeting CD19 has demonstrated notable clinical efficacy in the treatment of B-cell acute lymphoblastic leukemia (B-ALL), but its wider clinical applicability is constrained by long manufacturing processes, substantial costs, and severe adverse events. A potentially safer and more accessible alternative is provided by CAR-Natural killer (CAR-NK) cell therapy. Currently, most CAR-NK cells are generated using viral transduction, which is labor-intensive and associated with risks of genomic integration. Electroporation of CAR-encoding mRNA provides a non-integrating alternative but results in only transient CAR expression. Circular RNA (circRNA), owing to its enhanced stability and prolonged protein expression capacity, has recently emerged as a promising alternative to linear mRNA. To overcome the limitations of transient mRNA expression, we generated circRNA using a Group II intron-mediated cyclization system incorporating a newly selected Coccidioides immitis-derived Group II intron. The newly established Coccidioides immitis-derived Group II intron circularization system efficiently generated circRNA and supported more durable EGFP expression than linear mRNA in both HEK293T and NK92 cells. Using this system, we successfully developed a circRNA-based CD19-targeted CAR-NK platform. CircRNA-engineered CD19-targeted CAR-NK92 cells maintained more durable CAR expression and showed stronger antitumor activity at later time points. In mouse models of B-ALL, circRNA-engineered CAR-NK92 cells demonstrated better tumor control and extended survival compared with their linear mRNA-engineered counterparts. These results support the potential of circRNA-based CAR-NK therapy as an effective approach for enhancing the safety and efficacy of cancer immunotherapy.

Humans↗

PubMed2026

Construction of circRNA-miRNA-mRNA regulatory networks in the intestine of turbot (Scophthalmus maximus) following Vibrio anguillarum infection.

Circular RNAs (circRNAs) play pivotal roles in post-transcriptional regulation by acting as molecular sponges for microRNAs (miRNAs) within the competitive endogenous RNA (ceRNA) network. However, the regulatory mechanisms in teleost immune responses remain poorly understood. In this study, circRNA-miRNA-mRNA networks were investigated in turbot (Scophthalmus maximus) following Vibrio anguillarum infection to elucidate host-pathogen interactions. Through high-throughput sequencing of intestinal tissues, a total of 50 differentially expressed circRNAs (DE-circRNAs) (18 at 2 hpi, 16 at 12 hpi, 16 at 48 hpi), 212 DE-miRNAs (11 at 2 hpi, 70 at 12 hpi, 15 at 48 hpi), and 1774 DE-mRNAs were identified. Functional enrichment analyses (GO/KEGG) revealed significant associations with immune pathways, including the MAPK signaling pathway and gap junction. An integrated circRNA-miRNA-mRNA regulatory network was constructed, highlighting key interactions including novel_circ_0002573/DE-miR-27a-3p/FGB and novel_circ_0002423/novel_347/GNE, which may regulate inflammatory and antibacterial responses. The expression patterns of selected circRNAs, miRNAs and mRNAs were validated using qRT-PCR, confirming the reliability of the sequencing results. Importantly, fibrinogen beta chain (FGB) and CXCR4/CXCL12 signaling were identified as critical immune modulators. These findings provide insights of the ceRNA regulatory networks involved in teleost intestinal immunity and provide potential molecular targets for selective breeding of disease resistance in this species.

Animals↗

PubMed2025

Comprehensive circRNA expression profile and hub genes screening during human liver development.

BACKGROUND: Understanding the expression of non-coding RNA in the liver during embryonic development provides important insights into liver diseases. Therefore, we investigated circular RNA (circRNA) roles in human liver development, an unexplored research domain. METHODS: Using high-throughput sequencing and bioinformatics, we analysed foetal liver samples across developmental stages (7-20 weeks post-conception). Differentially expressed (DE) genes were identified and subjected to enrichment analysis using Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG), and Disease Ontology (DO). Modular analysis was performed using the Search Tool for Retrieval of Interacting Genes (STRING), followed by construction of a protein-protein interaction (PPI) network using Cytoscape software. The key genes were screened using Molecular Complex Detection (MCODE). The mRNA levels of hub genes were validated using quantitative reverse transcription polymerase chain reaction (qRT-PCR). RESULTS: There were 645 DE circRNAs and 5,145 DE mRNAs between human livers at the three growth stages (HB, EH, and LH). It was found that the activity of circRNAs was boosted remarkably in the hepatoblastic stage. Enrichment analysis found they mainly involved in nervous system regulation of liver function, embryonic organ development and digestive system development. In addition, DE circRNAs were primarily involved in the PI3K-AKT, MAPK and calcium pathways, potentially contributing to adult liver diseases. Notably, only hsa_circ_001471 and novel_circ_017382 were simultaneously identified at all stages and were persistently downregulated. A co-expression regulatory network involving these circRNAs was established. Three hub genes (LGR5, FOXL1 and RSPO3) were identified from the PPI network of 167 genes and may play key roles in human liver development. The RT-qPCR validation results were in agreement with the sequencing data. CONCLUSIONS: Our findings provide the first insights into the roles and regulatory networks of circRNAs in human liver development, laying the groundwork for further investigations of molecular and signalling networks.

Humans↗

PubMed2026

CircExor enables interpretable prediction of circRNA localization into extracellular vesicles.

Certain circular RNAs (circRNAs) are selectively enriched in extracellular vesicles (EVs), in which they contribute to intercellular communication and represent promising biomarkers, yet the sequence determinants of their sorting remain unclear. Existing computational predictors are optimized mainly for linear RNAs and rarely address circRNA localization into EVs. Here we introduce circExor, the first framework specifically designed for circRNA EV localization. We curate a dedicated benchmark data set of 2102 circRNAs and implement a variable-length end-to-end concatenation strategy together with k-mer frequency encoding to accommodate circular topology, long sequence length, and length heterogeneity. Using a tree-based classifier, circExor achieves superior performance compared with RNAlocate-v3 and ExoGRU, reaching an AUROC of 0.743 on the internal test set and an average AUROC of 0.680 on the held-out test set. SHAP-based analysis, sequence perturbation analysis, motif mapping, and cell-based experimental validation support the predicted EV tendency and identify YBX1, HNRNPK, HNRNPL, and NOVA2 as candidate RBPs potentially associated with circRNA sorting. CircExor therefore provides a predictive and interpretable framework that links in silico modeling to mechanistic hypotheses, and supports biomarker discovery and candidate prioritization for downstream studies of EV-associated circRNAs.

Journal Article↗

PubMed2024

RNA-seq reveals differentially expressed lncRNAs and circRNAs and their associated functional network in HTR-8/Svneo cells under hypoxic conditions.

Placental hypoxia is hazardous to maternal health as well as fetal growth and development. Preeclampsia and intrauterine growth restriction are common pregnancy problems, and one of the causes is placental hypoxia. Placental hypoxia is linked to a number of pregnancy illnessesv. To investigate their potential function in anoxic circumstances, we mimicked the anoxic environment of HTR-8/Svneo cells and performed lncRNA and circRNA studies on anoxic HTR-8/Svneo cells using high-throughput RNA sequencing. The miRNA target genes were predicted by integrating the aberrant expression of miRNAs in the placenta of preeclampsia and intrauterine growth restriction, and a ceRNA network map was developed to conduct a complete transcriptomic and bioinformatics investigation of circRNAs and lncRNAs. The signaling pathways in which the genes were primarily engaged were predicted using GO and KEGG analyses. To propose a novel explanation for trophoblastic organism failure caused by lncRNAs and circRNAs in an anoxic environment.

Humans↗

PubMed2026

Circular RNAs orchestrate integrated post-transcriptional responses to combined heat and drought stress in rice.

Circular RNAs (circRNAs) are emerging post-transcriptional regulators, yet their landscape and functional roles in rice under combined abiotic stress remain largely unexplored. Here, we systematically reanalyzed strand-specific RNA-seq data to characterize circRNAs responsive to simultaneous heat and drought stress. Following quality control, read mapping, and dual-algorithm prediction using CIRI2 and CIRCexplorer2, we identified 208 high-confidence circRNAs distributed across all 12 chromosomes. Comparative profiling revealed 83 circRNAs uniquely expressed in control samples, 51 in stressed samples, and 74 shared between conditions, indicating stress-dependent circularization. Junction-read analysis highlighted a spectrum of circularization strength, ranging from highly abundant circRNAs with dominant junction reads to low-confidence candidates masked by linear transcript background. Genomic annotation showed that circRNAs primarily originated from exonic and intergenic regions, with a pronounced negative-strand bias; several genes generated multiple circRNA isoforms via alternative back-splicing. Functional enrichment of host genes suggested involvement in protein folding, nutrient reservoir activity, RNA degradation, and branched-chain amino acid catabolism, implicating roles in stress adaptation and metabolic regulation. Differential expression analysis identified seven circRNAs specifically induced under combined stress conditions. Network topology analysis pinpointed key miRNAs-including osa-miR414, osa-miR1439, and osa-miR2919-as candidate topological hubs within the predicted network. Their predicted target genes, such as those encoding stress-responsive transcription factors and signaling proteins, suggest potential roles in coordinating post-transcriptional responses to combined stress. Network topology analysis pinpointed key miRNAs-including osa-miR414, osa-miR1439, and osa-miR2919-as candidate topological hubs within the predicted network. Their predicted target genes, such as those encoding stress-responsive transcription factors and signaling proteins, suggest potential roles in coordinating post-transcriptional responses to combined stress. Overall, this study provides a comprehensive map of circRNAs in rice under combined heat and drought stress, suggests their potential as ceRNAs based on predictive analysis, and lays a foundation for future experimental validation of circRNA-mediated regulation.

Oryza↗

PubMed2017

Circular RNA profiling reveals an abundant circLMO7 that regulates myoblasts differentiation and survival by sponging miR-378a-3p.

Circular RNAs (circRNAs) have been identified from various tissues and species, but their regulatory functions during developmental processes are not well understood. We examined circRNA expression profiles of two developmental stages of bovine skeletal muscle (embryonic and adult musculus longissimus) to provide first insights into their potential involvement in bovine myogenesis. We identified 12 981 circRNAs and annotated them to the Bos taurus reference genome, including 530 circular intronic RNAs (ciRNAs). One parental gene could generate multiple circRNA isoforms, with only one or two isoforms being expressed at higher expression levels. Also, several host genes produced different isoforms when comparing development stages. Most circRNA candidates contained two to seven exons, and genomic distances to back-splicing sites were usually less than 50 kb. The length of upstream or downstream flanking introns was usually less than 105 nt (mean≈11 000 nt). Several circRNAs differed in abundance between developmental stages, and real-time quantitative PCR (qPCR) analysis largely confirmed differential expression of the 17 circRNAs included in this analysis. The second part of our study characterized the role of circLMO7-one of the most down-regulated circRNAs when comparing adult to embryonic muscle tissue-in bovine muscle development. Overexpression of circLMO7 inhibited the differentiation of primary bovine myoblasts, and it appears to function as a competing endogenous RNA for miR-378a-3p, whose involvement in bovine muscle development has been characterized beforehand. Congruent with our interpretation, circLMO7 increased the number of myoblasts in the S-phase of the cell cycle and decreased the proportion of cells in the G0/G1 phase. Moreover, it promoted the proliferation of myoblasts and protected them from apoptosis. Our study provides novel insights into the regulatory mechanisms underlying skeletal muscle development and identifies a number of circRNAs whose regulatory potential will need to be explored in the future.

Animals↗

PubMed2025

A Dual-Selection System for Enhanced Efficiency and Fidelity of Circular RNA Overexpression.

Circular RNAs (circRNAs) are essential regulators of cellular processes, but are challenging to study using traditional methods. Overexpression approaches, such as the use of linearized plasmids and viral vectors, often result in high rates of false-positive clones, where cells retain selection markers without expressing the target circRNA. This study addresses this limitation by developing a dual-selection circRNA system designed to enhance the accuracy and reliability of circRNA overexpression. Our system integrates a fluorescent reporter gene upstream of the circRNA expression cassette, under a shared promoter, and a downstream antibiotic resistance marker, allowing for both antibiotic selection and flow cytometric cell-sorting to identify and enrich cells with genuine circRNA expression. We successfully incorporated this system into an inducible lentiviral vector for controlled overexpression in various cell types. The dual-selection circRNA system offers a significant advance for circRNA research and studies of other RNA species where accurate and reliable overexpression is essential.

RNA, Circular↗

PubMed2025

Circular RNAs orchestrating breast cancer hallmarks: bridging tumor biology and therapy resistance.

Breast cancer (BC) remains a leading cause of cancer-related mortality among women worldwide, with treatment resistance posing a significant clinical challenge. Circular RNAs (circRNAs), a class of non-coding RNAs, have gained increasing attention as key regulators of gene expression, influencing BC pathogenesis, progression, and therapeutic response. This review explores the mechanistic insights into circRNA functions in BC, focusing on their involvement in tumor proliferation, metabolic reprogramming, epithelial-mesenchymal transition (EMT), angiogenesis, metastasis, and apoptosis. Additionally, we highlight the crosstalk between circRNAs and microRNAs, emphasizing their potential as diagnostic and prognostic biomarkers. Beyond their roles in tumor biology, circRNAs are implicated in drug resistance, modulating responses to chemotherapy, targeted therapy, and endocrine treatment. Despite their promising applications, challenges remain, including the complexity of circRNA interactions, and the development of robust preclinical models. Addressing these challenges through interdisciplinary research integrating genomics, transcriptomics, and functional studies will pave the way for circRNA-based therapeutic strategies and personalized medicine approaches in BC management.

Humans↗

PubMed2026

Circular RNAs in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive loss of motor neurons, with most cases lacking a clear genetic basis. Emerging evidence highlights the involvement of non-coding RNAs, particularly circular RNAs (circRNAs), in disease onset and progression. Here, we investigated circRNAs implicated in ALS and related motor neuron diseases (MNDs). Here, we provide a general overview of circular RNA metabolism and cellular functions. We then present our systematic literature review that identified ALS-associated circRNAs, followed by in silico analyses of 15 circular RNA candidates that were selected based on the most compelling data regarding ALS. Our results revealed that several circular RNAs regulate ALS-related genes, such as unfolded protein response, oxidative stress, cell cycle regulation, and apoptosis. Protein-RNA interaction analysis further showed that ALS-related circRNAs can sponge 20 RNA-binding proteins. Additionally, molecular docking analysis demonstrated that ALS-associated FUS variants significantly alter its binding affinity to circular RNAs. RNA-seq data from ALS patients confirmed significant alterations in the expression of host genes of ALS-related circRNAs and hub proteins in ALS-affected CNS tissues. Collectively, our findings identify circRNAs as potential key contributors to ALS pathogenesis.

Amyotrophic Lateral Sclerosis↗

PubMed2026

Enhancing Lipid Nanoparticle-Mediated Circular RNA and mRNA Expression in the Placenta through Inhibition of IFNAR-JAK-STAT Signaling.

The placenta has emerged as a promising target for RNA lipid nanoparticle (LNP)-based therapies to treat obstetric complications, yet efficient extrahepatic RNA transfection remains a challenge. Here, we identify innate immune signaling as a regulator of placental RNA translation and demonstrate that inhibition of IFN-α/β receptor (IFNAR) and JAK-STAT signaling enhances LNP-mediated transgene expression in the placenta for both messenger RNA (mRNA) and circular RNA (circRNA). While a placenta-tropic LNP enabled robust and durable circRNA expression in trophoblasts in vitro, circRNA translation was substantially decreased in vivo compared to mRNA in pregnant mice. Inhibition of IFNAR-JAK-STAT signaling enhanced circRNA translation up to 12-fold in maternal organs and increased circRNA and mRNA translation in the placenta up to 17.5- and 4-fold, respectively. JAK-STAT inhibition also enhanced translation of therapeutically relevant VEGF-encoding circRNA and mRNA in pregnant mice, suggesting innate immune modulation as a broadly applicable strategy to improve RNA therapeutics during pregnancy.

Female↗

PubMed2026

A novel peptide encoded by circTLL1 drives osimertinib resistance in lung cancer by modulating the NT5C2/Ras/PI3K axis.

BACKGROUND: Acquired resistance to osimertinib, a third-generation EGFR tyrosine kinase inhibitor, remains a major clinical challenge in the treatment of non-small cell lung cancer (NSCLC). Although circular RNAs (circRNAs) have been increasingly implicated in drug resistance, most studies have focused on their canonical role as microRNA sponges, while their capacity to encode functional micropeptides remains largely unexplored. This study aimed to identify novel circRNAs involved in osimertinib resistance and to characterize their regulatory functions at the protein level. METHODS: Osimertinib-resistant (OR) NSCLC cell lines were established and validated. High-throughput RNA sequencing was performed to compare the circRNA expression profiles between parental and OR cells. The function of the candidate circRNA was assessed through a series of in vitro and in vivo experiments, including cell viability assays, apoptosis analysis, and xenograft mouse models. Mechanistic investigations involved mass spectrometry, co-immunoprecipitation and western blotting to explore its protein-coding potential and downstream signaling pathways. RESULTS: We identified a novel circRNA, termed circTLL1, that was stably and significantly upregulated in OR-NSCLC cells. Functionally, overexpression of circTLL1 promoted osimertinib resistance, whereas its knockdown restored drug sensitivity both in vitro and in vivo. Mechanistically, we discovered that circTLL1 harbors an open reading frame (ORF) that is translated into a novel 90-amino-acid protein, which we designated circTLL1-90aa. Further investigation revealed that circTLL1-90aa directly interacts with and promotes the degradation of 5'-nucleotidase, cytosolic II (NT5C2), thereby uncoupling nucleotide metabolism from its normal regulatory constraints. The consequent downregulation of NT5C2 leads to elevated GTP levels and leading to the sustained activation of the downstream Ras/PI3K/AKT signaling pathway. CONCLUSION: Our findings unveil a previously unrecognized circRNA/micropeptide/metabolism cascade underlying osimertinib resistance. The identification of the circTLL1-90aa/NT5C2/Ras/PI3K axis not only expands the functional repertoire of the non-coding genome but also provides new insights into the complexity of drug resistance. Given its selective upregulation in resistant cells, circTLL1-90aa holds promise both as a predictive biomarker for treatment stratification and as an actionable therapeutic target, offering a novel strategy to overcome osimertinib resistance in NSCLC patients.

Pyrimidines↗

PubMed2026

Cancer stemness-modulating (CSM) proteins in pan-cancer chemoresistance: regulatory roles and mechanisms.

Cancer stemness is a property of cancer cells that plays critical roles in tumorigenesis and therapeutic resistance. We previously identified and categorized, based on literature evidence, a group of fourteen cancer stemness-modulating (CSM) circular RNAs (circRNAs) in colorectal cancer (CRC), which we termed CSM-circRNAs. In the present work, we show that the proteins regulated by these CRC CSM-circRNAs, with one exception for which information is currently unavailable, are bona fide modulators of cancer stemness across a wide range of cancer types. We, therefore, designate these proteins as CSM-proteins. As chemoresistance is a major trait of cancer stemness, we further investigated the molecular mechanisms through which CSM-proteins contribute to chemoresistance. Our analysis reveals that twelve CRC CSM-proteins are implicated in chemoresistance across fourteen cancer types and resistance to ten therapeutic agents. Nine distinct chemoresistance mechanisms are identified and organized into five broader functional axes: survival, drug processing, genome maintenance, plasticity and adaptation, leading us to propose an integrated mechanistic framework for CSM-protein-mediated chemoresistance. Most CSM-proteins operate across multiple functional axes in different cancer contexts, with survival-associated mechanisms, particularly apoptosis evasion, and epithelial-mesenchymal transition-associated plasticity emerging as the predominant modes of chemoresistance. Furthermore, transcriptional regulatory CSM-proteins exhibit broader mechanistic profiles than other molecular categories, although the strength and extent of evidence vary across proteins and cancer types. Taken together, the proposed CSM-protein pan-cancer chemoresistance framework offers a biologically and therapeutically relevant regulatory network for understanding the mechanisms underlying cancer chemoresistance based predominantly on preclinical evidence. Our findings may provide a preclinical conceptual foundation for the development of combinatorial therapeutic strategies targeting cancer stemness and chemoresistance through the CSM-circRNA-CSM-protein regulatory axis.

Cancer stemness↗

PubMed2026

Target site selection and P1 engineering enable highly efficient circular RNA production via end-to-end self-targeting and splicing.

Circular RNAs (circRNAs) are more stable than linear RNAs, enabling expanding applications in RNA vaccines and therapeutics. We previously developed an in vitro circRNA preparation method based on end-to-end self-targeting and splicing (STS) using the Tetrahymena group I intron, which generates circRNAs without extraneous sequences. However, self-circularization efficiency declines as gene of interest (GOI) length increases, limiting its application to longer GOIs. Here, we systematically optimized key determinants of STS efficiency, including target site selection and P1 construct engineering. Target site screening revealed that selection of optimal target sites within each GOI markedly improved self-circularization efficiency. Moreover, engineering of the P1 construct, including incorporation of a polyA10 sequence upstream of the internal guide sequence of the intron and an antisense sequence complementary to the target site and its upstream region at the 5' side of polyA10, further enhanced efficiency. Notably, the optimized STS strategy achieved up to two-fold higher self-circularization efficiency than the conventional permuted intron-exon (PIE) method for long GOIs (∼8 K-nt). Collectively, these results establish an improved STS workflow for efficient circRNA production without extraneous sequences across a wide range of GOI lengths, outperforming the PIE method for long GOIs, and broadening biomedical applications.

RNA, Circular↗

PubMed2026

Comparative transcriptome analysis reveals ncRNA-mediated regulatory networks associated with muscle crispiness in grass carp.

Non-coding RNAs (ncRNAs) have been demonstrated to be involved in muscle development and to function as key regulators. However, the molecular mechanism underlying muscle crispiness in grass carp (GC) remains poorly understood, and whether these ncRNAs are involved in its regulation is still unknown. In the current investigation, differentially expressed (DE) RNAs (including lncRNAs, circRNAs, miRNAs, and mRNAs) were identified; concomitantly, target genes prediction was conducted, and functional and signaling pathway enrichment analyses were performed. Pathways related to muscle crispiness were identified, and the competitive endogenous RNA (ceRNA) (lncRNA/circRNA-miRNA-mRNA) regulatory network was further constructed. The results showed that a total of 126 DE-lncRNAs, 17 DE-circRNAs, 329 DE-miRNAs, and 442 DE-mRNAs were identified in muscle tissues of both the GC and crisp grass carp (CGC). GO and KEGG enrichment analyses revealed that target genes of DE-ncRNAs were significantly enriched in signaling pathways, including structural constituents of muscle, apoptosis, oxidative phosphorylation, and regulation of actin cytoskeleton, suggesting that these pathways may be involved in muscle texture remodeling. Subsequently, DE-RNAs enriched in related pathways were identified, and a core ceRNA regulation network comprising 3 lncRNAs, 4 circRNAs, 3 miRNAs, and 17 mRNAs was constructed. Additionally, 10 DE-RNAs from randomly selected groups were validated by qRT-PCR. Our findings not only provide scientific evidence elucidating the molecular mechanisms underlying muscle crispiness in GC but also establish a foundation for studying changes in muscle textural qualities across other fish species.

Animals↗

PubMed2025

Detecting and quantifying circular RNAs in terabyte-scale RNA-seq datasets with CIRI3.

To address recent challenges in circular RNA (circRNA) analysis, we present CIRI3, a tool for circRNA detection and quantification in terabyte-scale RNA-sequencing datasets. Using dynamic multithreaded task partitioning and a blocking search strategy for junction reads, CIRI3 is an order of magnitude faster than existing tools, while providing increased accuracy. We identified differentially spliced circRNAs across 2,535 cancer-related samples, and constructed a pretraining model and a biomarker network provided as the CIRIonco database.

RNA, Circular↗