Establishments of G3BP1-GFP stress granule monitoring system for real-time stress assessment in human neuroblastoma cells.

Acute stress caused by short-term exposure to deleterious chemicals can induce the aggregation of RNA-binding proteins (RBPs) in the cytosol and the formation of stress granules (SGs). The cytoplasmic RBP, Ras GTPase-activating protein-binding protein 1 (G3BP1) is a critical organizer of SG, and its aggregation is considered a hallmark of cellular stress. However, assembly of SG is a highly dynamic process that involves RBPs; hence, existing methods based on fixation processes or overexpression of RBPs exhibit limited efficacy in detecting the assembly of SG under stress conditions. In this study, we established a G3BP1- Green fluorescent protein (GFP) reporter protein in a human neuroblastoma cell line to overcome these limitations. GFP was introduced into the G3BP1 genomic sequence via homologous recombination to generate a G3BP1-GFP fusion protein and further analyze the aggregation processes. We validated the assembly of SG under stress conditions using the G3BP1-GFP reporter system. Additionally, this system supported the evaluation of bisphenol A-induced SG response in the established human neuroblastoma cell line. In conclusion, the established G3BP1-GFP reporter system enables us to monitor the assembly of the SG complex in a human neuroblastoma cell line in real time and can serve as an efficient tool for assessing potential neurotoxicity associated with short-term exposure to chemicals.

Mangifera Indica leaf extracts promote hair growth via activation of Wnt signaling pathway in human dermal papilla cells.

The crosstalk between androgens and Wnt signaling pathways is critical in the hair growth cycle. Therefore, natural products that target these two pathways for the inhibition of hair loss are sought after. In this study, we investigated the effect of water extracts of Mangifera indica leaves (WEML) on hair growth. WEML treatment significantly reduced the expression levels of both dickkopf-1 (DKK1) and type 2 5α-reductase (SRD5A2) involved in Wnt signal suppression activity and dihydrotestosterone (DHT) synthesis, respectively, in human follicle dermal papilla cells (HFDP). In addition, WEML treatment effectively upregulated Wnt target genes and downregulated DKK1 expression that was increased by DHT treatment. Degranulation analysis in rat basophilic leukemia mast cell line (RBL-2H3) using ß-hexosaminidase release assay confirmed that WEML did not exhibit allergenic activity. Furthermore, hair growth was significantly enhanced in in vivo mice model treated with WEML. These results suggest that M. indica leave extract contains bioactive materials that can be used to treat hair loss.

Flavobacterium hydrocarbonoxydans sp. nov., isolated from polluted soil.

This paper presents a polyphasic taxonomic study of a Gram-stain-negative bacterium designated GA093T, a soil isolate capable of benzo(α)pyrene degradation. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain GA093T is a member of the genus Flavobacterium, and formed an independent phylogenetic line while clustering with the type strains of Flavobacterium hibernum, Flavobacterium branchiarum and Flavobacterium hydatis. Strain GA093T was facultatively anaerobic, and could grow at 4-33 °C (optimum, 30 °C), at pH 6-11 (optimum, pH 7) and in the presence of 0-2 % (w/v) NaCl (optimum, 0 %). Strain GA093T was capable of producing acid from various carbon sources, which was comparable to other related species of Flavobacterium. The strain contained MK-6 as the only isoprenoid quinone, iso-C15 : 0 as the major cellular fatty acid, phosphatidylethanolamine and phosphatidylinositol as diagnostic polar lipids, and sym-homospermidine as the major polyamine. The chemotaxonomic properties of strain GA093T were consistent with the general properties of Flavobacterium except the presence of phosphatidylinositol, which distinguished it from other related species. The total stretch of the obtained genome of GA093T was 5.05 Mbp, and the DNA G+C content was 34.79 mol%. The genome contained genes potentially related to the degradation of aromatic hydrocarbons. On the basis of the present polyphasic analysis, strain GA093T was found to have properties that distunguished it as representing a novel species of the genus Flavobacterium, for which the name Flavobacterium hydrocarbonoxydans sp. nov. is proposed. The type strain is GA093T (=KCTC 72594T=LMG 31760T).