Endoplasmic reticulum stress response modulator OsbZIP39 regulates cadmium accumulation via activating the expression of defensin-like gene OsCAL2 in rice.

Accumulation of cadmium (Cd) in rice is not only harmful to the growth of plants but also poses a threat to human health. Exposure to Cd triggers unfolded protein response (UPR) within cells, a process that is still not completely understood. The study demonstrated that the lack of OsbZIP39, an essential endoplasmic reticulum (ER)-resident regulator of the UPR, resulted in decreased Cd intake and reduced Cd levels in the roots, stems, and grains of rice. Upon exposure to Cd stress, GFP-OsbZIP39 translocated from ER to nucleus, initiating UPR. Further investigation revealed that Cd treatment caused changes in sphingolipid levels in the membrane, influencing the localization and activation of OsbZIP39. Yeast one-hybrid and dual-LUC assays were conducted to validate the interaction between activated OsbZIP39 and the promoter of the defensin-like gene OsCAL2, resulting in an increase in its expression. Different variations were identified in the coding region of OsbZIP39, which may explain the varying levels of Cd accumulation observed in the indica and japonica subspecies. Under Cd treatment, OsbZIP39ind exhibited a more significant enhancement in the transcription of OsCAL2 compared to OsbZIP39jap. Our data suggest that OsbZIP39 positively regulates Cd uptake in rice, offering an encouraging objective for the cultivation of low-Cd rice.

PatWRKY71 transcription factor regulates patchoulol biosynthesis and plant defense response.

Patchoulol, a valuable compound belonging to the sesquiterpenoid family, is the primary component of patchouli oil produced by Pogostemon cablin (P. cablin). It has a variety of pharmacological and biological activities and is widely used in the medical and cosmetic industries. However, despite its significance, there is a lack of research on the transcriptional modulation of patchoulol biosynthesis.Salicylic acid (SA), is a vital plant hormone that serves as a critical signal molecule and plays an essential role in plant growth and defense. However, to date, no studies have explored the modulation of patchoulol biosynthesis by SA. In our study, we discovered that the application of SA can enhance the production of patchoulol. Utilizing transcriptome analysis of SA-treated P. cablin, we identified a crucial downstream transcription factor, PatWRKY71. The transcription level of PatWRKY71 was significantly increased with the use of SA. Furthermore, our research has revealed that PatWRKY71 was capable of binding to the promoter of PatPTS, ultimately leading to an increase in its expression. When PatWRKY71 was silenced by a virus, the expression of both PatWRKY71 and PatPTS was reduced, resulting in the down-regulation of patchoulol production. Through our studies, we discovered that heterologous expression of PatWRKY71 leads to an increase in the sensitivity of Arabidopsis to salt and Cd, as well as an outbreak of reactive oxygen species (ROS). Additionally, we uncovered the regulatory role of PatWRKY71 in both patchoulol biosynthesis and plant defense response. This discovery provided a theoretical basis for the improvement of the content of patchoulol and the resistance of P. cablin through genetic engineering.

[Biosynthesis and metabolism regulation of terpenoids in Pogostemon cablin: a review].

The terpenoids in Pogostemon cablin have complex structures and abundant pharmacological effects. Patchouli alcohol(PA) and pogostone(PO) have a high medicinal value by virtue of anti-tumor, anti-inflammatory, antibacterial, antioxidant, and other biological activities. Due to the low content of terpenoid metabolites in P. cablin, the study of biosynthesis and metabolism regulation can provide a biosynthetic basis for obtaining high-content terpenoids. In this study, key enzyme genes in biosynthesis, transcription factors in metabolism regulation, spatio-temporal expression of terpene synthase were reviewed, aiming to provide a reference for the development, protection, and utilization of P. cablin resources.

[Effects of 5-azacytidine on DNA methylation and index components in patchouliol-type Pogostemon cablin].

This study aims to explore the relationship of DNA methylation with the contents of the index components as well as the growth and development of Pogostemon cablin. The demethylation reagent 5-azacytidine(5-azaC) was used to treat the tissue culture seedlings of patchouliol-type P. cablin. High performance liquid chromatography was employed to evaluate the changes of DNA methy-lation in P. cablin, and GC-MS to detect the contents of index components in P.cablin. The agronomic characters of P.cablin were measured using the common methods. The results showcased that DNA methylation of P.cablin was significantly reduced by 5-azaC in a concentration-dependent manner. Thirty days after treatment with 5-azaC at different concentrations, the content of patchouli alcohol changed slightly; compared with that in the control group, the content of pogostone in 50 µmol·L~(-1) and 100 µmol·L~(-1) 5-azaC groups was significantly up-regulated. The 100 µmol·L~(-1) 5-azaC group had the largest differences in contents of pogostone and patchouli alcohol compared with the control group, followed by the 50 µmol·L~(-1) 5-azaC group. Ninety days after disinhibition, the content of pogostone in the treatment group was significantly increased and the content of patchouli alcohol was significantly decreased. In addition, 5-azaC significantly inhibited the growth and development of P.cablin in a dose-dependent manner. These results indicate that DNA methylation regulates the biosynthesis of the index components in patchouliol-type P.cablin and proper demethylation can directly promote the synthesis of pogostone and indirectly affect the accumulation of patchouli alcohol.

Corrigendum: CDX2/mir-145-5p/SENP1 Pathways Affect LNCaP Cells Invasion and Migration.

[This corrects the article DOI: 10.3389/fonc.2019.00477.].

Hsa_Circ_0007843 Acts as a mIR-518c-5p Sponge to Regulate the Migration and Invasion of Colon Cancer SW480 Cells.

Circular RNA (circRNA), a type of RNA that is widely expressed in mammalian cells, is considered to be essential in tumorigenesis. CircRNA can regulate target gene expression by interacting with the corresponding microRNA (miRNA). Our preliminary results showed that the expression levels of 1,817 circRNAs were significantly different in colon cancer tissue compared with paracancerous tissue, of which 1,236 were upregulated and 581 were downregulated. By using RT-PCR, we confirmed that the expression of hsa_circ_0007843, hsa_circ_0010575, hsa_circ_0007331, and hsa_circ_0001615 was significantly higher in colon cancer tissue than in normal colonic tissue; however, the expression levels of hsa_circ_0014879 and hsa_circRNA_401801 were not significantly different between normal and neoplastic colonic tissue. Among the circRNAs that were confirmed to be upregulated in colon cancer tissue, hsa_circ_0007843 was also found to be highly expressed in colon cancer SW480 cells. Overexpression of hsa_circ_0007843 promoted the invasion and migration of SW480 cells, whereas its downregulation suppressed their invasion and migration. Overexpression of hsa_circ_0007843 promoted tumor growth, whereas its downregulation inhibited tumor growth. We found that hsa_circ_0007843 interacted with miR-518c-5p and suppressed its expression, and miR-518c-5p interacted with matrix metallopeptidase 2 (MMP2) and promoted its expression and translation. Taken together, this study demonstrated that hsa_circ_0007843 acted as an miRNA sponge to regulate MMP2 expression by removing the inhibitory effect of miR-518c-5p on MMP2 gene translation, which further affected the invasive capability of SW480 cells.

hsa_circ_0006459 and hsa_circ_0015962 affect prognosis of Dengue fever.

Circular ribonucleic acids (circRNAs) are widely expressed in human cells and play an important role in the pathogenesis of many diseases. Some circRNAs have microRNA (miRNA) binding response elements and interact with miRNA to regulate the expression of target genes.Four patients with a preliminary diagnosis of dengue fever (DF), peripheral whole blood sample in anticoagulant was collected before treatment (pretreatment group) and after effective treatment (posttreatment group), and eight samples were separated and used to screen differentially expressed circRNAs with microarray analysis. The relative expression level of circRNAs was determined using reverse-transcription polymerase chain reaction (RT-PCR). TargetScan v7.1 and miRDB v5 bioinformatics software were used to predict circRNA-binding miRNAs; dual luciferase reporters were constructed to detect binding between circRNA and miRNA. Microarray screening revealed 263 differentially expressed circRNAs in peripheral leukocytes pretreatment versus posttreatment; 107 of these were upregulated and 156 were downregulated. RT-PCR confirmed that hsa_circ_0015962 was significantly upregulated and hsa_circ_0006459 significantly downregulated (P < 0.05). Moreover, hsa_circ_0015962 binds to miR-4683, and hsa_circ_0006459 binds to miR-133b.Downregulation of hsa_circ_0006459 and upregulation of hsa_circ_0015962 affect the treatment response of DF and are potential biomarkers in DF patients. The molecular mechanism involves hsa_circ_0006459-mediated targeted negative regulation of miR-133b and hsa_circ_0015962-mediated targeted negative regulation of miR-4683.

CDX2/mir-145-5p/SENP1 Pathways Affect LNCaP Cells Invasion and Migration.

Background/Aims: Recently, rapidly accumulating evidence has shown that microRNAs (miRNAs) are involved in human tumorigenesis, and the dysregulation of miRNAs has been observed in many cancers, including prostate cancer. miR-145-5p, an miRNA with reduced expression in prostate cancer cells, has been shown to have a tumor suppressive role in a variety of tumors. However, its underlying mechanism requires further elucidation. Methods: A lentiviral expression vector for miR-145-5p was constructed and used to establish a stable cell line (LNCaP) expressing miR-145-5p. The cells were cultured normally and divided into the control group (control), negative control group (negative control), and test group (miR-145-5p). Inhibition of proliferation was measured by a WST-8 assay. The early apoptosis rate of cells was detected by flow cytometry. Clone formation ability was detected by a clone formation inhibition test. Cell invasion and migration capacity was detected by a Transwell assay. The relative expression levels of proteins were detected by western blotting. We constructed a nude mouse model of prostate cancer to observe the effect of miR-145-5p on the growth of transplanted tumors. TargetScan bioinformatics software was used to predict target genes regulated by miR-14-5p. ChIPBase was used to predict transcription factors with binding sites in the upstream promoter region of miR-145-5p. Quantitative reverse transcription PCR was used to detect the relative expression level of genes. A bifluorescence-reporter gene vector was constructed to confirm the regulation of target genes by miR-145-5p. We used 5' rapid amplification of cDNA ends to confirm the transcription start site of miR-145-5p.Chromatin immunoprecipitation technology was used to detect the effect of transcription factors binding to miR-145-5p. Results: The overexpression of miR-145-5p not only inhibited the proliferation, invasion, and migration of LNCaP cells but also promoted their early apoptosis. After overexpressing miR-145-5p, the expression of small ubiquitin-like modifier protein-specific protease 1 (SENP1), and caudal-related homeobox 2 (CDX2) protein was decreased in LNCaP cells. The transcription factor CDX2 bound to the miR-145-5p promoter region and inhibited its transcription. The transcription start site of miR-145-5p was located at a guanine residue 1,408 bp upstream of the stem-loop sequence. Upon overexpression, miR-145-5p could bind to the 3'-untranslated region of SENP1 to inhibit its translation. Conclusion: These results suggested that CDX2 inhibits the expression of miR-145-5p, thereby relieving the inhibitory effect of miR-145-5p on the translation of SENP1 and affecting the invasion and migration of prostate cancer cells.

The CircRNA-ACAP2/Hsa-miR-21-5p/ Tiam1 Regulatory Feedback Circuit Affects the Proliferation, Migration, and Invasion of Colon Cancer SW480 Cells.

BACKGROUND/AIMS: Circular RNAs (circRNAs), a type of RNA that is widely expressed in human cells, have essential roles in the development and progression of cancer. CircRNAs contain microRNA (miRNA) binding sites and can function as miRNA sponges to regulate gene expression by removing the inhibitory effect of an miRNA on its target gene. METHODS: We used the bioinformatics software TargetScan and miRanda to predict circRNA-miRNA and miRNAi-Mrna interactions. Rate of inhibiting of proliferation was measured using a WST-8 cell proliferation assay. Clone formation ability was assessed with a clone formation inhibition test. Cell invasion and migration capacity was evaluated by performing a Transwell assay. Relative gene expression was assessed using quantitative real-time polymerase chain reaction and relative protein expression levels were determined with western blotting. circRNA and miRNA interaction was confirmed by dual-luciferase reporter and RNA-pull down assays. RESULTS: In the present study, the miRNA hsa-miR-21-5p was a target of circRNA-ACAP2, and T lymphoma invasion and metastasis protein 1 (Tiam1) was identified as a target gene of hsa-miR-21-5p. CircRNA-ACAP2 and Tiam1 were shown to be highly expressed in colon cancer tissue and colon cancer SW480 cells, but miR-21-5p was expressed at a low level. SW480 cell proliferation was suppressed when the expression of circRNA-ACAP2 and Tiam1 was decreased and the expression of miR-21-5p was increased in vivo and in vitro. SW480 cell migration and invasion were also inhibited under the same circumstance. The circRNA-ACAP2 interaction regulated the expression of miR-21-5p, and miR-21-5p regulated the expression of Tiam1. Down-regulation of circRNA-ACAP2 promoted miR-21-5p expression, which further suppressed the transcription and translation of Tiam1. CONCLUSION: The present study shows that the circRNA-ACAP2/hsa-miR-21-5p/Tiam1 regulatory feedback circuit could affect the proliferation, migration, and invasion of colon cancer SW480 cells. This was probably due to the fact that circRNA-ACAP2 could act as a miRNA sponge to regulate Tiam1 expression by removing the inhibitory effect of miR-21-5p on Tiam1 expression. The results from this study have revealed new insights into the pathogenicity of colon cancer and may provide novel therapeutic targets for the treatment of colon cancer.

In vitro induction and morphological characteristics of octoploid plants in Pogostemon cablin.

This paper describes an efficient colchicine-mediated technique for in vitro induction of octoploids in Pogostemon cablin and its confirmation by flow cytometry and chromosome numbers. The highest octoploid induction ratio was obtained by 0.05% colchicine treatment for 72 h. The chromosome number of octoploid seedlings was 2n = 8x = 128. Colchicine-induced tetraploids and octoploids planted in soil remained stable after 6 months. There were 31 lines of octoploid plants obtained. The leaf characteristics of P. cablin tetraploids and octoploids were compared. The larger leaves and stomata of transplants can be used to identify putative octoploids in P. cablin. Most octoploid lines exhibited higher patchoulic alcohol contents than the controls after 6 months of cultivation. Our results demonstrated that polyploidy induction can be beneficial in improving the medicinal value of P. cablin.

[Pharmacognostical study on Berchemia floribunda].

OBJECTIVE: To study the pharmacognostical characteristics of stem and root of Berchemia floribunda for its further research and usage. METHODS: The plant was researched by macroscopic identification, microscopic identification and thin layer chromatography. RESULTS: The transverse section of B. floribunda root was eccentric. There were many fiber bundles in the secondary phloem and two different stone cells distributed in stem and root respectively. The results of TLC could identify the stem and root of B. floribunda. CONCLUSION: The microscopic characteristics of B. floribunda stem and root can be used as reference for its identification. Quercetin can be used as the characteristic component to identify the stem and root.

[Primary study on dormancy and release method for Berchemia lineata seed].

OBJECTIVE: To explore the mechanism of the seed dormancy of Berchemia lineatea and the method of breaking the dormancy. METHODS: Hundred-seed method, TTC and imbibition method was used to measure thousand seeds weight, seed viability and hard seed percentage, respectively. The germination inhibitor's biological characteristic was identified from the extract of every part in its fructification. Four treatments were compared to explore the best way to break physical and biological dormancy such as 98% sulfuric acid, hot water,grit friction and GA3. RESULTS: The thousand seeds weight was 10.82 g, the percentage of hard seed was up to 100%, viability was 83%, its water absorption speed and absorption rate were relatively low. Being treated with 98% sulfuric acid for 10 minutes, the seed improved its germination rate to 85%, and significantly improved its germination potentiality to 41%. Every part of the fructification contained germination inhibitors. The strongest inhibitory effect was found in seed testa and embryo. 500 and 1 000 mg/L GA3 significantly improved seed's germination potentiality to 48% and 43%. CONCLUSION: Berchemia lineata seed is hard to germinate because of its physical and biological dormancy, which is one reason for the resource reduction of Berchemia lineata.

Rapid in vitro propagation of medicinally important Aquilaria agallocha.

Aquilaria agallocha can produce fragrant agarwood used for incense, traditional medicine and other products. An efficient plant regeneration system was established via organogenesis from shoots developed from seedlings of Aquilaria agallocha. Shoots generated many buds on MS medium supplemented with 1.3 micromol/L BA (6-benzylaminopurine) in the first 7 weeks, and the buds elongated on MS medium with 1.3 micromol/L BA+0.5 micromol/L NAA (naphthaleneacetic acid) in another 7 weeks, 2.3 shoots 2 cm in length per explant were obtained within 14 weeks. Plantlets were rooted on 1/2 MS medium after being immersed in 5 micromol/L NAA for 48 h, 96.7% of the roots grew up two weeks later. All plantlets that survived acclimatization grew well in the pots.