Objective: This study aimed to identify internal ribosome entry sites (IRESs) in the open reading frame (ORF) of the Coxsackievirus B3 (CVB3) genome. Methods: The sequences of P1, P2, or P3 of the CVB3 genome or the truncated sequences from each antithymocyte globulin (ATG) to the end of the P1, P2, or P3 gene were inserted into the pEGFP-N1 vector. After transfection, possible IRES-dependent green fluorescent protein (GFP)-fused proteins were detected by anti-GFP western blotting. The sequences of possible IRESs were inserted into specific Fluc/Rluc bicistronic vectors, in which the potential IRESs were determined according to the Fluc/Rluc activity ratio. Expression of Fluc and Rluc mRNA of the bicistronic vector was detected by RT-qPCR. Results: After transfection of full length or truncated sequences of the P1, P2, or P3 plasmids, six GFP-fused protein bands in P1, six bands in P2 and nine bands in P3 were detected through western blotting. Two IRESs in VP2 (1461-1646 nt) and VP1 (2784-2983 nt) of P1; one IRES in 2C (4119-4564 nt) of P2; and two IRESs in 3C (5634-5834 nt) and 3D (6870-7087 nt) of P3 were identified according to Fluc/Rluc activity ratio. The cryptic promoter was also excluded by RT-qPCR. Conclusion Five IRESs are present in the CVB3 coding region.
Internal Ribosome Entry Sites/genetics* ; Open Reading Frames ; RNA, Messenger/genetics*

Circular RNA (circRNA) is a single-stranded circular closed RNA molecule formed from linear RNA through reverse splicing. circRNAs are stable, highly conserved, and tissue-specific. circRNAs can regulate physiological and pathological processes through various mechanisms such as formation of competing endogenous RNA and interaction with binding proteins. It has been recently revealed that circRNAs can be translated into peptides and proteins to participate in the initiation and development of cancer. circRNAs are promising diagnostic and prognostic markers for human cancers as well as potential drug targets for cancer therapy. This review summarized the research progresses related to circRNA-encoded peptides and proteins in a variety of cancers. These peptides and proteins are translated through two different mechanisms that depend on internal ribosome entry site and m6A, respectively. We also summarized the potential use of circRNA-encoded peptides and proteins in the diagnosis, treatment, prognosis and mechanistic studies of various cancers.
Humans ; Internal Ribosome Entry Sites ; Neoplasms/genetics* ; Peptides, Cyclic ; RNA/genetics* ; RNA, Circular/genetics*

The special nucleic acid fragments, 5' untranslated region (5' UTR) and internal ribosome entry site (IRES) of foot-and-mouth disease virus (FMDV), which interact with the capsid proteins, were selected as scaffolds to investigate the assembly efficiency of foot-and-mouth disease (FMD) virus-like particles (VLPs). The assembled product was characterized by evaluation of particle size, surface potential, gel retardation assay, nuclease digestion experiments, size-exclusion chromatography, transmission electron microscopy and circular dichroism analysis. The results confirmed that the 5' UTR and IRES of FMDV co-assembled with the FMD VLPs and facilitated the assembly efficiency of FMD-VLPs. It demonstrates that the assembly efficiency of 75S particles of VLPs-5'UTR was significantly higher than those of the VLPs (P<0.001) and VLPs-IRES group (P<0.01). Comparatively the assembly efficiency of 12S particles of VLPs-IRES was significantly higher than those of the VLPs (P<0.000 1) and VLPs-5'UTR (P<0.000 1). It showed that the 5' UTR represented more effective in facilitating the assembly of VLPs. This study proposes an optimized strategy for improving the assembly efficiency of VLPs for the development of VLPs vaccine.
5' Untranslated Regions ; Capsid Proteins/metabolism* ; Foot-and-Mouth Disease Virus/physiology* ; Internal Ribosome Entry Sites ; Nucleic Acids/metabolism* ; Virus Assembly

14-3-3 Proteins ; genetics ; metabolism ; Animals ; Brain ; pathology ; Cricetinae ; Internal Ribosome Entry Sites ; Open Reading Frames ; Prion Diseases ; genetics ; metabolism