ABSTRACT
With the development of high-throughput sequencing technology, circular RNAs (circRNAs) have gradually become a hotspot in the research on non-coding RNA. CircRNAs are produced by the covalent circularization of a downstream 3' splice donor and an upstream 5' splice acceptor through backsplicing, and they are pervasive in eukaryotic cells. CircRNAs used to be considered byproducts of false splicing, whereas an explosion of related studies in recent years has disproved this misconception. Compared with the rich studies of circRNAs in animals, the study of circRNAs in plants is still in its infancy. In this review, we introduced the discovery of plant circRNAs, the discovery of plant circRNAs, the circularization feature, expression specificity, conservation, and stability of plant circRNAs and expounded the identification tools, main types, and biogenesis mechanisms of circRNAs. Furthermore, we summarized the potential roles of plant circRNAs as microRNA (miRNA) sponges and translation templates and in response to biotic/abiotic stress, and briefed the degradation and localization of plant circRNAs. Finally, we discussed the challenges and proposed the future directions in the research on plant circRNAs.
Subject(s)
Animals , MicroRNAs/metabolism , Organelle Biogenesis , Plants/metabolism , Protein Biosynthesis/physiology , RNA, Circular/metabolism , RNA, Plant/metabolism , Research/trends , Stress, Physiological/geneticsABSTRACT
Circular RNAs (circRNAs) are universal and diverse endogenous non-coding RNAs which widely found in eukaryotic cells.They form covalently closed, continuous and stable ring structure, which play the role of microRNA (miRNA) molecular sponge and regulate gene transcription and selective splicing.These molecules offer new potential opportunities for therapeutic intervention and serve as biomarkers for diagnosis.This paper provides an overview of the formation, function and detection methods of circRNAs, and summarizes the biological role of circRNAs in the development and progression of diseases such as nervous system diseases, cardiovascular diseases, cancer and infection, and provides evidence for the potential use of circRNAs in diagnosis.
ABSTRACT
PURPOSE: Long noncoding RNA 00703 (LINC00703) was found originating from a region downstream of Kruppel-like factor 6 (KLF6) gene, having 2 binding sites for miR-181a. Since KLF6 has been reported as a target of miR-181a in gastric cancer (GC), this study aims to investigate whether LINC00703 regulates the miR-181a/KLF6 axis and plays a functional role in GC pathogenesis.MATERIALS AND METHODS: GC tissues, cell lines, and nude mice were included in this study. RNA binding protein immunoprecipitation (RIP) and pull-down assays were used to evaluate interaction between LINC00703 and miR-181a. Quantitative real-time polymerase chain reaction and western blot were applied for analysis of gene expression at the transcriptional and protein levels. A nude xenograft mouse model was used to determine LINC00703 function in vivo.RESULTS: We revealed that LINC00703 competitively interacts with miR-181a to regulate KLF6. Overexpression of LINC00703 inhibited cell proliferation, migration/invasion, but promoted apoptosis in vitro, and arrested tumor growth in vivo. LINC00703 expression was found to be decreased in GC tissues, which was positively correlated with KLF6, but negatively with the miR-181a levels.CONCLUSIONS: LINC00703 may have an anti-cancer function via modulation of the miR-181a/KLF6 axis. This study also provides a new potential diagnostic marker and therapeutic target for GC treatment.
Subject(s)
Animals , Mice , Apoptosis , Binding Sites , Blotting, Western , Cell Line , Cell Proliferation , Gene Expression , Heterografts , Immunoprecipitation , In Vitro Techniques , Mice, Nude , Real-Time Polymerase Chain Reaction , RNA, Long Noncoding , RNA-Binding Proteins , Stomach NeoplasmsABSTRACT
Circular RNA (circRNA) is a non-coding closed-loop single-stranded RNA molecule lacking the 5' end cap and the 3' poly (A) tail. Circular RNA is more abundant and stable than linear mRNA, and its expression is more conservative and specific. circRNA regulates cancer development through a variety of mechanisms, including miRNA sponges, regulating gene transcription, regulating RNA-binding proteins, and protein translation. This review summarizes the role of circRNA in cancer and helps to develop new clinical diagnostic techniques and treatments.
ABSTRACT
Circular RNAs(circRNAs)are a novel type of RNA that function as microRNA(miRNA)sponges,RNA-binding proteins,and regulators of nuclear transcription.CircRNAs play a dual role in cancer,wherein their function as miRNA sponges could lead to either an oncogenic stimulus or tumor suppression.CircRNAs can also serve as novel diagnostic and prognostic biomarkers,as well as thera-peutic targets for cancer;both these functions have great potential for clinical application in cancer diagnosis and therapy.Here,we re-view the mechanisms of action and potential clinical applications of circRNAs in tumors.
ABSTRACT
@#Circular RNAs (circRNAs) are RNAs with a covalently closed loop structure, characterized by its conservation, stability, tissue specific and ubiquity. CircRNAs can serve as miRNA ‘sponges’ to modulate the mRNA targets of miRNAs. CircRNAs can bind with RNA binding proteins and regulate the expression of some genes. The differential expression of circRNAs between pathogenic and normal tissues makes circRNAs possibly promising biomarkers for diagnosis and targets for treatment. In this article, we reviewed the research progress of circRNA and discussed its research prospects in oral diseases.
ABSTRACT
Objective:To explore the effect and mechanism of miRNA sponge on the epithelial-mesenchymal transition (EMT) of gastric carcinoma cell lines SGC7901. Methods:Synthetic ZEB2 3'UTR plasmid and siRNA targeting ZEB2 were transfected into the SGC7901 cell line by Lipofectamine 2000. Real-time quantitative polymerase chain reaction was performed to evaluate the expres-sion levels of miR-200a/b/c. Finally, the migratory, invasive, and proliferative activities of the gastric carcinoma cells in vitro were ana-lyzed by the scratch test, the Transwell cell invasion, and the cell cloning assay. The expression of the target protein was detected by Western blot. Results:Compared with the control group, the expressions of miR-200a/b/c significantly decreased, and their migration, invasion, and proliferation capabilities were considerably higher after they were transfected with ZEB2 3'UTR. Although the expres-sions of miR-200a/b/c significantly increased, the migratory, invasive, and proliferative activities of SGC7901 cells also degraded after they were transfected with siRNA targeting ZEB2. The expression of ZEB2 increased, and that of E-cadherin decreased at the protein level after they were transfected with ZEB2 3'UTR. The protein expression of Vimentin in SGC7901 cells significantly increased. The indicators show the opposite trend when cells were transfected with siZEB2, and the differences between the control and mutation groups were insignificant. Conclusion:ZEB2 3'UTR can regulate EMT course by regulating the miR-200a/b/c expression in gastric car-cinoma, consequently regulating the invasion and migration of carcinoma cells.