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SUMMARY: Plant cells employ intricate defense mechanisms, including mRNA decay pathways, to counter viral infections. Among the RNA quality control (RQC) mechanisms, nonsense‐mediated decay (NMD), no‐go decay (NGD), and nonstop decay (NSD) pathways play critical roles in recognizing and cleaving aberrant mRNA molecules. Turnip crinkle virus (TCV) is a plant virus that triggers mRNA decay pathways, but it has also evolved strategies to evade this antiviral defense. In this study, we investigated the activation of mRNA decay during TCV infection and its impact on TCV RNA accumulation. We found that TCV infection induced the upregulation of essential mRNA decay factors, indicating their involvement in antiviral defense and the capsid protein (CP) of TCV, a well‐characterized viral suppressor of RNA silencing (VSR), also compromised the mRNA decay‐based antiviral defense by targeting AtXRN4. This interference with mRNA decay was supported by the observation that TCV CP stabilized a reporter transcript with a long 3′ untranslated region (UTR). Moreover, TCV CP suppressed the decay of known NMD target transcripts, further emphasizing its ability to modulate host RNA control mechanisms. Importantly, TCV CP physically interacted with AtXRN4, providing insight into the mechanism of viral interference with mRNA decay. Overall, our findings reveal an alternative strategy employed by TCV, wherein the viral coat protein suppresses the mRNA decay pathway to facilitate viral infection. Significance Statement: Unveil a novel strategy used by TCV to counter host defense and enhance its own infections. [ABSTRACT FROM AUTHOR]

Most plant viruses encode suppressors of RNA silencing (VSRs) to protect themselves from antiviral RNA silencing in host plants. The capsid protein (CP) of Turnip crinkle virus (TCV) is a well‐characterized VSR, whereas SUPPRESSOR OF GENE SILENCING 3 (SGS3) is an important plant‐encoded component of the RNA silencing pathways. Whether the VSR activity of TCV CP requires it to engage SGS3 in plant cells has yet to be investigated. Here, we report that TCV CP interacts with SGS3 of Arabidopsis in both yeast and plant cells. The interaction was identified with the yeast two‐hybrid system, and corroborated with bimolecular fluorescence complementation and intracellular co‐localization assays in Nicotiana benthamiana cells. While multiple partial TCV CP fragments could independently interact with SGS3, its hinge domain connecting the surface and protruding domains appears to be essential for this interaction. Conversely, SGS3 enlists its N‐terminal domain and the XS rice gene X and SGS3 (XS) domain as the primary CP‐interacting sites. Interestingly, SGS3 appears to stimulate TCV accumulation because viral RNA levels of a TCV mutant with low VSR activities decreased in the sgs3 knockout mutants, but increased in the SGS3‐overexpressing transgenic plants. Transgenic Arabidopsis plants overexpressing TCV CP exhibited developmental abnormalities that resembled sgs3 knockout mutants and caused similar defects in the biogenesis of trans‐acting small interfering RNAs. Our data suggest that TCV CP interacts with multiple RNA silencing pathway components that include SGS3, as well as previously reported DRB4 (dsRNA‐binding protein 4) and AGO2 (ARGONAUTE protein 2), to achieve efficient suppression of RNA silencing‐mediated antiviral defence. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common cancers. Maternally expressed gene 3 (MEG3, one kind of long noncoding RNA [lncRNA]) can act as a tumor suppressor and regulate P53 target gene expression. However, lncRNA MEG3 demonstrates relatively low or no expression in human HCC. This study provides a promising concept to codeliver lncRNA and pDNA for cancer therapy. As proof-of-concept, the pcDNA-MEG3 and pcDNA-P53 plasmids-condensed nanocomplexes with the liver-targeting polycation gene vector, pullulan-based ethanolamine-modified poly(glycidyl methacrylate) (denoted as PuPGEA), are proposed to codeliver lncRNA and pDNA to treat HCC. Pullulan-containing nanovectors are shown to be able to effectively mediate gene delivery in liver cells. To assess gene delivery performances of PuPGEA, a series of assays such as in vitro gene transfection, HCC cell proliferation, colony formation, migration, matrigel transwell assays, and in vivo xenograft animal models are carried out. The codelivery system with PuPGEA/(MEG3+P53) nanocomplexes demonstrates additive effects in suppressing HCC compared to PuPGEA/MEG3 or PuPGEA/P53 nanocomplexes alone. These results suggest that codelivery of lncRNA and pDNA by polycation nanovectors is a promising method to treat cancers. [ABSTRACT FROM AUTHOR]

5S rRNA plays an important part in ribosome biology and is over-expression in multiple cancers. In this study, we found that 5S rRNA is a direct target of miR-150 and miR-383 in esophageal squamous cell carcinoma (ESCC). Overexpression of miR-150 and miR-383 inhibited ESCC cell proliferation in vitro and in vivo. Moreover, 5S rRNA silencing by miR-150 and miR-383 might intensify rpL11–c-Myc interaction, which attenuated role of c-Myc as an oncogenic transcriptional factor and dysregulation of multiple c-Myc target genes. Taken together, our results highlight the involvement of miRNAs in ribosomal regulation during tumorigenesis. [ABSTRACT FROM AUTHOR]

treRNA is a long non-coding RNA (lncRNA) involved in cancer progression. In this study, we show that miR-190a can silence treRNA post-transcriptionally. Suppression of treRNA by miR-190a led to significant changes of mesenchymal–epithelial transition markers and impaired migration and invasion capability of hepatoma cells. TCGA data indicated that miR-190a exhibited lower expression in hepatoma tissues, especially from patients with vascular tumor invasion, compared to normal tissues. Our results reveal the involvement of miR-190a–treRNA axis in hepatoma progression and shed light on lncRNA-based cancer therapies for hepatoma patients at high risk of metastasis. [ABSTRACT FROM AUTHOR]

Two new 2D hybrid compounds derived from Keggin-type [ BW12O40]5− anion, proline and 4,4'-bipy were synthesized, namely, [ CoII2(proline)(4,4'-bipy)( H4,4'-bipy)2( OH)( H2O)2][ BW12O40]• 3H2O ( 1) and [ CoII3(proline)2(4,4'- bipy)2( H4,4'-bipy)4( OH)2( H2O)4][ BW12O40]2• 6H2O ( 2). They are characterized by single-crystal X-ray diffraction, FT-IR spectra, powder X-ray diffraction ( PXRD), thermogravimetric analyses ( TGA) and XPS spectra. All compounds represent 2D framework, but the structures possess some distinctions to a certain degree. In compound 1, 1D wave-like chains are formed. The chains and polyanions are stacked each other in an ABAB fashion to yield a 2D network. However, compared with compound 1, compound 2 exhibits the same construction except for the opposite arrangement mode. Moreover, their electrochemical behaviors and fluorescence properties have been investigated. The electrochemical properties show that compounds 1, 2 display good electrocatalytic activities for the reduction of nitrite. [ABSTRACT FROM AUTHOR]