Background: Flavonoids of Hypericum perforatum are important secondary metabolites which have been widely utilized in medicine for a range of purposes. The use of methyl jasmonate (MeJA) elicitation for the enhancement of flavonoid production in cell suspension culture of H. perforatum would be an efficient alternative method for the flavonoid production. Results: MeJA influenced the cells growth and flavonoid production. The optimal elicitation strategy was treatment of the cell cultures with 100 μmol/L MeJA on day 15, which resulted in the highest flavonoid production (280 mg/L) and 2.7 times of control cultures. The activities of catalase (CAT) were inhibited after MeJA treatment in the cell cultures, while the activities of phenylalanine ammonia lyase (PAL) increased, which led to the enhancement of flavonoid production. Conclusion: MeJA elicitation is a useful method for the enhancement of flavonoid production in cell suspension culture of H. perforatum.

HighlightAtNSE1 and AtNSE3 are crucial factors for early embryo and seedling development, and mutations of AtNSE1 and AtNSE3 can affect cell division and the DNA repair process.

Background Some natural compounds inhibit cancer cell growth in various cancer cell lines with fewer side effects than traditional chemotherapy. Here, we explore the pharmacological effects and mechanisms of worenine (isolated from Coptis chinensis) against colorectal cancer. Methods The effects of worenine on colorectal cancer cell proliferation, colony formation and cell cycle distribution were measured. Glycolysis was investigated by examining glucose uptake and consumption, lactate production, and the activities and expressions of glycolysis enzymes (PFK-L, HK2 and PKM2). HIF-1α was knocked down and stimulated in vitro to investigate the underlying mechanisms. Results Worenine somewhat altered the glucose metabolism and glycolysis (Warburg effect) of cancer cells. Its anti-cancer effects and capability to reverse the Warburg effect were similar to those of HIF-1α siRNA and weakened by deferoxamine (an HIF-1α agonist). Conclusion It is suggested that worenine targets HIF-1α to inhibit colorectal cancer cell growth, proliferation, cell cycle progression and the Warburg effect.

Since Colombia is one of the countries with the highest production of carnations worldwide, it is of great economic importance for the flower sector to prevent the disease fusariosis, the main cause of crop losses, by acquiring resistant varieties to this vascular disease caused by Fusarium oxysporum f. sp. Dianthi (FOX). In order to make an approach to the comprehension and knowledge of the response of carnation varieties to the presence of FOX, the main objective of this degree thesis was to study the gene expression (mRNA) between susceptible and resistant varieties of carnation during the elicitation with such pathogen. For this, first, mRNA was extracted from de-differentiated carnation cells, cultured in vitro, under elicitated and non-elicitated conditions with silica membrane technology.Second, a transcriptomic library was obtained through RNA-seq sequencing as well as the relative abundance of each transcript. With this information, the variation of the gene response in terms of mRNA produced by susceptible and resistant varieties of carnation to FOX, was analyzed. Finally, groups of genes that could participate in the resistance phenotype in carnation varieties with the presence of FOX were detected.

Replication factor C (RFC) is a conserved eukaryotic complex consisting of RFC1/2/3/4/5. It plays important roles in DNA replication and the cell cycle in yeast and fruit fly. However, it is not very clear how RFC subunits function in higher plants, except for the Arabidopsis (At) subunits AtRFC1 and AtRFC3. In this study, we investigated the functions of AtRFC4 and found that loss of function of AtRFC4 led to an early sporophyte lethality that initiated as early as the elongated zygote stage, all defective embryos arrested at the two- to four-cell embryo proper stage, and the endosperm possessed six to eight free nuclei. Complementation of rfc4-1/+ with AtRFC4 expression driven through the embryo-specific DD45pro and ABI3pro or the endosperm-specific FIS2pro could not completely restore the defective embryo or endosperm, whereas a combination of these three promoters in rfc4-1/+ enabled the aborted ovules to develop into viable seeds. This suggests that AtRFC4 functions simultaneously in endosperm and embryo and that the proliferation of endosperm is critical for embryo maturation. Assays of DNA content in rfc4-1/+ verified that DNA replication was disrupted in endosperm and embryo, resulting in blocked mitosis. Moreover, we observed a decreased proportion of late S-phase and M-phase cells in the rfc4-1/- seedlings, suggesting that incomplete DNA replication triggered cell cycle arrest in cells of the root apical meristem. Therefore, we conclude that AtRFC4 is a crucial gene for DNA replication.