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It is known that laccase genes are involved in lignin synthesis. Eucalyptus is an important timber species; functional studies of specific laccase members and their upstream regulatory factors in Eucalyptus are incomplete, and the mechanism of lignin content variation in polyploid plants remains unclear. Therefore, in this study, we investigated the function of EuLAC17 by overexpressing it in tobaccos and the result showed the lignin content in transgenic tobacco increased significantly. Further, yeast one hybrid sequencing was used to identify a series of potential regulatory factors of EuLAC17 , among which EuMYB308 showed the most significant correlation with EuLAC17. Yeast one hybrid, dual-luciferase reporter gene assay and electrophoretic mobility shift assay jointly verified that EuMYB308 could directly target the EuLAC17 promoter and repress its expression. In addition, overexpression of EuMYB308 resulted in significant reductions in plant growth, xylem cell lumen area, cell wall thickness and lignin content. Transcriptome sequencing showed that lignin biosynthesis genes including laccase genes were significantly differential expression in transgenic plants compared with wild-type plants. In triploid Eucalyptus urophylla , the expression of EuMYB308 was significantly upregulated, which may enhance the inhibition of EuLAC17 and thus reduce its expression level in triploid, which is one possible reason for the reduced lignin content in triploid E. urophylla. This study provides important insights into transcriptional regulation of lignin biosynthesis in Eucalyptus , and also contributes to revealing the genetic mechanism of lignin content variation in polyploid plants, which are of great significance for promoting the improvement of wood quality in forest trees and polyploid breeding. • EuMYB308 has an important influence on the regulation of lignin content in Eucalyptus urophylla. • A mode of negative regulation of lignin content by EuMYB308 targeting EuLAC17 was identified. • Differential expression of EuMYB308 may be an important reason for the reduced lignin content in triploid Eucalyptus. [ABSTRACT FROM AUTHOR]

Esophageal cancer is one of the most malignant gastrointestinal malignancies. Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer in China. In recent years, with developments in basic medicine, it has been demonstrated that the abnormal expression of circular RNA (circRNA) plays an important role in the progression and prognosis of ESCC. This study explored the role and downstream molecular mechanisms of circ_0046534 in ESCC. We identified circ_0046534, which was found to be highly expressed in ESCC tissues and cells. Moreover, the downregulation of circ_0046534 inhibited the proliferation, migration and invasion of ESCC cells and the growth and metastasis of ESCC tumours in vivo. Dual-luciferase reporter assays showed that circ_0046534 sponged miR-339-5p and inhibited the expression of miR-339-5p. Furthermore, MMP2 was identified to be a direct target of miR-339-5p through bioinformatics analysis. In addition, the knockdown of circ_0046534 inhibited the expression of the downstream target gene matrix metalloproteinase 2 (MMP2) by releasing the adsorption of miR-339-5p. Taken together, this study demonstrated that silencing circ_0046534 inhibited the growth and metastasis of ESCC through the miR-339-5p/MMP2 pathway. Circ_0046534 is expected to serve as a new biomarker and target for ESCC and provide a new direction for its diagnosis and treatment. [Display omitted] • High expression of hsa_circ_0046534 in ESCC accelerated the metastasis and growth of ESCC through miR-339-5p/MMP2 signaling pathway. [ABSTRACT FROM AUTHOR]

Ginseng is a valuable medicinal herb used in China for the prevention and treatment of cancer, diabetes, cardiovascular diseases and other diseases. As the main active ingredient of ginseng, ginsenoside has a wide range of pharmacological effects. Ginsenoside Rh2, a protopanaxadiol saponin from ginseng, exhibits anti-inflammatory and anticancer effects. The potential biological mechanism of Rh2 in the treatment of ulcerative colitis (UC) has not been clarified clearly. In our research, we aimed to explore the therapeutic effects of Rh2 on dextran sodium sulfate (DSS)-induced colitis and elucidate the mechanism of Rh2 in treating UC. DSS-induced UC mice were established and randomly divided into the following four groups: control group, DSS group, Rh2 (50 mg/kg) group and sulfasalazine (SASP, 200 mg/kg) group. Except for the control group, 3% DSS drinking water was given to each group for 7 days, and the other two groups were intragastrically administered with Rh2 and SASP for 10 days. At the end of the experiment, colon samples were collected, and phenotypic and pathological analyses were performed in UC mice. Then, Western blot, immunohistochemistry and quantitative real-time PCR analyses were performed to determine the expression of signaling pathway-related factors. Rh2 markedly alleviated DSS-induced body weight loss, intestinal damage, colon length shortening and disease activity index (DAI) scores. Furthermore, proinflammatory cytokines, such as TNF-α, IL-6 and IL-1β, were reduced by Rh2. Additionally, STAT3/miR-214 activation was also suppressed by Rh2 administration. In vitro , we demonstrated that Rh2 effectively inhibited IL-6-induced STAT3 phosphorylation and miR-214 expression in cultured normal colonic epithelial cells. Our results suggested that Rh2 exhibits potential application value in the treatment of UC, and its mechanism is related to the downregulation of STAT3/miR-214 levels, which is expected to be applicable in the treatment of clinical UC. [Display omitted] [ABSTRACT FROM AUTHOR]

• Circ_0000119 is an exonic circular RNA deriving from protein-coding locus MAN1A2. • Circ_0000119 promotes gastric cancer cells proliferation and migration in vitro and in vivo. • miR-502-5p is sponged by circ_0000119 and thus MTBP is upregulated, favoring gastric cancer progression. Dysregulated circular RNAs (circRNAs) are significantly related with tumor initiation and progression. However, biological activity and potential molecular mechanism of circRNAs in gastric cancer (GC) deserve further exploration. We carried out total RNA sequencing and acquired the expression profiles of circRNAs. Quantitative real-time PCR as well as RNA in situ hybridization helped to validate circ_0000119 dysregulation. Various in vitro experiments were utilized to investigate the biological activities of circ_0000119 in GC, and the clinical relation of circ_0000119 in vivo was identified through nude mouse xenograft models. Finally, the molecular mechanism of circ_0000119 was clarified via luciferase assays, western blot, and rescue experiments. Compared with adjacent normal tissues, the study found an increase in the expression of circ_0000119 as well as its host linear gene MAN1A2 in GC tissues. Circ_0000119 overexpression promoted proliferation and migration of GC cells in vitro and in vivo, whereas circ_0000119 suppression had the opposite effect. Mechanistically, circ_0000119 sponged miR-502-5p which played an inhibitory role in tumors. Furthermore, we found that miR-502-5p alleviated GC progression through targeting MTBP and downregulating its expression at mRNA and protein levels. In conclusion, our findings reveal a new regulatory mechanism for circ_0000119, which sponges the miR-502-5p, suppresses MTBP expression, and finally promotes GC progression. [ABSTRACT FROM AUTHOR]