Changes in the expression of COI1, TIR1, and ERF1 genes and respective MiRNAs in Fusarium basal Rot-Stressed onion.

Fusarium oxysporum f.sp. cepae (FOC), as basal rot fungus, is the most detrimental pathogen causing a serious threat to onion productivity in the world. In this study, we first determined FOC tolerance in seven Iranian onion cultivars, two known international onions (Texas Early Grano and Sweet Yellow Spanish), and an Allium species related to the onion (Allium asarence) based on the infection severity. Then, a transcriptional screen was performed by comparing the transcript levels of some pathogen-responsive genes (ERF1, COI1, and TIR1) and their predicted miRNAs in the sensitive (Ghermeze Azarshahr Cv.) and the resistant (A. asarence) onions to determine key genes and their miRNAs involved in the defense responses of onions to FOC. From our results, a difference was found in the COI1 and ERF1 expression 48 h after inoculation with FOC as compared to the respective 24 and 72 h. It can be explained by either special mechanisms involved in raising energy consumption efficiency or the interactive effects of other genes in the jasmonic acid (JA) and ethylene (ET) signaling pathways. Moreover, expression analysis of the pathogen-responsive genes and their targeting miRNAs identified the miR-5629, which targets the COI1 gene as a likely key factor in conferring resistance in the FOC-resistant onion, i.e., A. asarence. However, exploring the function of the miRNA/target pair is highly recommended to deeply understand the effect of the miRNA/target pair-associated pathway in the control of A. asarense-FOC interaction.

Methanolic extract of Artemisia absinthium prompts apoptosis, enhancing expression of Bax/Bcl-2 ratio, cell cycle arrest, caspase-3 activation and mitochondrial membrane potential destruction in human colorectal cancer HCT-116 cells.

The Artemisia absinthium (AA), belongs to the Asteraceae family, is used as a therapeutic agent in traditional medicine in Iran. It is a rich source of biology-active compounds. However, the molecular mechanism of AA contributing to cell proliferation and apoptosis is still unknown. This study aims to assess the anticancer activity of the methanolic extract of A. absinthium (MEAA) against human colorectal cancer HCT-116 cell line. The cytotoxic effects of MEAA on HCT-116 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. The expression levels of BAX and BCL-2 in HCT-116 cell line were examined by qRT-PCR. Annexin V/PI-flow cytometry technique was used to detect the cell cycle and apoptosis. MMP was predicted by Rhodamine 123 staining, and caspase 3 activity was analyzed by ELISA. Western blot method was performed to detect the expression level of BAX, Bcl-2 and Caspase-3 proteins. The MTT test revealed MEAA reduced the viability of HCT-116 cells. The mRNA and protein levels of BAX increased, but those of BCL-2 decreased in MEAA-treated cells. MEAA also prompted cell cycle arrest and induced apoptosis. After adding MEAA, the protein level and activity of caspase 3 and MMP destruction significantly increased. MEAA predominantly prompted apoptosis in HCT-116 cells by activating the mitochondrial pathway.

Identification and tissue-specific expression of rutin biosynthetic pathway genes in Capparis spinosa elicited with salicylic acid and methyl jasmonate.

Capparis spinosa is an edible medicinal plant which is considered as an excellent source of rutin. Rutin is a glycoside of the flavonoid quercetin that has been reported to have a beneficial role in controlling various diseases such as hypertension, arteriosclerosis, diabetes, and obesity. In this study, the partial cDNA of four genes involved in the rutin biosynthetic pathway including 4-coumaroyl CoA ligase (4CL), flavonoid 3'-hydroxylase (F3'H), flavonol synthase (FLS) and flavonol-3-O-glucoside L-rhamnosyltransferase (RT) were identified in C.spinosa plants for the first time. The protein sequences of these genes shared high similarity with the same proteins in other plant species. Subsequently, the expression patterns of these genes as well as rutin accumulation in C.spinosa leaves treated with different concentrations of salicylic acid (SA) and methyl jasmonate (MeJA) and also in different tissues of Caper plants treated with 100 mgL-1 SA and 150 µM MeJA were evaluated. The expression of all four genes was clearly up-regulated and rutin contents increased in response to MeJA and SA treatments after 24 h. The highest rutin contents (5.30 mgg-1 DW and 13.27 mgg-1 DW), as well as the highest expression levels of all four genes, were obtained using 100 mgL-1 SA and 150 µM MeJA, respectively. Among the different tissues, the highest rutin content was observed in young leaves treated with 150 µM MeJA, which corresponded to the expression of related genes, especially RT, as a key gene in the rutin biosynthetic pathway. These results suggest that rutin content in various tissues of C. spinosa can be enhanced to a significant extent by MeJA and SA treatments and the gene expression patterns of rutin-biosynthesis-related genes are regulated by these elicitors.

Phytochemical, antioxidant, enzyme activity and antifungal properties of Satureja khuzistanica in vitro and in vivo explants stimulated by some chemical elicitors.

Context: Satureja khuzistanica Jamzad. (Lamiaceae), is known for its antifungal and antioxidant compounds, especially rosmarinic acid (RA).Objective: The study examines the effect of elicitors on RA production and phytochemical properties of S. khuzistanica.Materials and methods: In vitro plants were treated with methyl jasmonate (MeJA) and multi-walled carbon nanotubes (MWCNTs). In vivo plants were treated with MWCNTs and salicylic acid (SA). RA was measured by HPLC. Catalase (CAT), guaiacol peroxidase (POD) and ascorbate peroxidase (APX) were quantified. DPPH and ß-carotene were assayed in in vivo extracts. The antifungal effects of extracts were evaluated against Fusarium solani K (FsK).Results: The highest RA contents of in vitro plants were 50 mg/L MeJA (140.99 mg/g DW) and 250 mg/L MWCNTs (140.49 mg/g DW). The highest in vivo were 24 h MWCNTs (7.13 mg/g DW) and 72 h SA (9.12 mg/g DW). The maximum POD and APX activities were at 100 mg/L MeJA (5 and 4 mg protein, respectively). CAT had the highest activities at 50 mg/L MeJA (2 mg protein). DPPH and ß-carotene showed 50% and 80% inhibition, respectively. The FsK aggregation was the lowest for in vitro extract in number of conidia [1.82 × 1010], fresh weight (6.51 g) and dry weight (0.21 g) that proved RA inhibitory effects. The callus reduces FsK growth diameter to 2.75 on the 5th day.Discussion and conclusions: Application of MeJA, SA, and MWCNTSs could increase RA in S. khuzistanica and highlighted potential characteristics in pharmaceutical and antifungal effects.

The effect of drought stress on the expression of key genes involved in the biosynthesis of triterpenoid saponins in liquorice (Glycyrrhiza glabra).

Glycyrrhiza glabra is an important medicinal plant throughout the world. Glycyrrhizin is a triterpenoid that is among the most important secondary metabolites produced by liquorice. Drought stress is proposed to enhance the levels of secondary metabolites. In this study, the effect of drought stress on the expression of important genes involved in the glycyrrhizin biosynthetic pathway was examined. Drought stress at the seedling stage was applied to 8-day-old plants using polyethylene glycol. Subsequently, the samples were collected 0, 4, 8 or 24 h post-treatment. At the adult plant stage, 10-month-old plants were subjected to drought stress by discontinuing irrigation. Subsequently, samples were collected at 2, 16 and 28 days after drought imposition (S(2d), S(16d) and S(28d), respectively). We performed semi-quantitative RT-PCR assays to evaluate the gene expression levels of sequalene synthase (SQS), ß-amyrin synthase (bAS), lupeol synthase (LUS) and cycloartenol synthase (CAS) during stress. Finally, the glycyrrhizin content of stolons was determined via HPLC. The results revealed that due to osmotic stress, the gene expression levels of SQS and bAS were increased, whereas those of CAS were relatively unchanged at the seedling stage. At the adult plant stage, the expression levels of SQS and bAS were increased under drought stress conditions, whereas the gene expression level of CAS remained relatively constant. The glycyrrhizin content in stolons was increased only under severe drought stress conditions (S(28d)). Our results indicate that application of controlled drought stress up-regulates the expression of key genes involved in the biosynthesis of triterpenoid saponins and directly enhances the production of secondary metabolites, including glycyrrhizin, in liquorice plants.