An iron-containing ferritin-based nanosensitizer for synergistic ferroptosis/sono-photodynamic cancer therapy.

Ferroptosis is a newly detected iron-dependent form of regulated cell death. Sono-photodynamic therapy (SPDT) can generate reactive oxygen species (ROS) and induce cell death under light and ultrasound. Due to the complexity of tumor physiology and pathology, single-modality often fails to achieve a satisfactory therapeutic effect. The development of a formulation platform with integration of multiple therapeutic modalities using a simple and convenient method is still a challenge. Here, we report the facile construction of a ferritin-based nanosensitizer FCD by co-encapsulating chlorin e6 (Ce6) and dihydroartemisinin (DHA) in horse spleen ferritin, and was employed for synergistic ferroptosis and SPDT. Ferritin in FCD can release Fe3+ under acidic conditions and Fe3+ can be reduced to Fe2+ in the presence of glutathione (GSH). The Fe2+ can react with hydrogen peroxide (H2O2) to produce harmful hydroxyl radicals. Furthermore, a large amount of ROS can be generated via the reaction of Fe2+ with DHA and by simultaneously irradiation of FCD with both light and ultrasound. More importantly, the depletion of GSH by FCD could decrease glutathione peroxidase 4 (GPX4) and increase lipid peroxidation (LPO) levels, thereby inducing ferroptosis. Therefore, by integrating the advantageous GSH-depletion capacity, ROS generation ability, and ferroptosis induction capability into one single nanosystem, FCD can serve as a promising platform for combined chemo-sono-photodynamic therapy of cancer.

The Osmotin-Like Protein Gene PdOLP1 Is Involved in Secondary Cell Wall Biosynthesis during Wood Formation in Poplar.

Osmotin-like proteins (OLPs) mediate defenses against abiotic and biotic stresses and fungal pathogens in plants. However, no OLPs have been functionally elucidated in poplar. Here, we report an osmotin-like protein designated PdOLP1 from Populus deltoides (Marsh.). Expression analysis showed that PdOLP1 transcripts were mainly present in immature xylem and immature phloem during vascular tissue development in P. deltoides. We conducted phenotypic, anatomical, and molecular analyses of PdOLP1-overexpressing lines and the PdOLP1-downregulated hybrid poplar 84K (Populus alba × Populus glandulosa) (Hybrid poplar 84K PagOLP1, PagOLP2, PagOLP3 and PagOLP4 are highly homologous to PdOLP1, and are downregulated in PdOLP1-downregulated hybrid poplar 84K). The overexpression of PdOLP1 led to a reduction in the radial width and cell layer number in the xylem and phloem zones, in expression of genes involved in lignin biosynthesis, and in the fibers and vessels of xylem cell walls in the overexpressing lines. Additionally, the xylem vessels and fibers of PdOLP1-downregulated poplar exhibited increased secondary cell wall thickness. Elevated expression of secondary wall biosynthetic genes was accompanied by increases in lignin content, dry weight biomass, and carbon storage in PdOLP1-downregulated lines. A PdOLP1 coexpression network was constructed and showed that PdOLP1 was coexpressed with a large number of genes involved in secondary cell wall biosynthesis and wood development in poplar. Moreover, based on transcriptional activation assays, PtobZIP5 and PtobHLH7 activated the PdOLP1 promoter, whereas PtoBLH8 and PtoWRKY40 repressed it. A yeast one-hybrid (Y1H) assay confirmed interaction of PtoBLH8, PtoMYB3, and PtoWRKY40 with the PdOLP1 promoter in vivo. Together, our results suggest that PdOLP1 is a negative regulator of secondary wall biosynthesis and may be valuable for manipulating secondary cell wall deposition to improve carbon fixation efficiency in tree species.

[Effects of land use change on soil labile organic carbon in Central Jiangxi of China].

Selecting the 15-year abandoned land (AL) and three forest lands [Phyllostachys edulis plantation (PE), Schima superba secondary forest (SS), and Cunninghamia Lanceolata plantation (CL)] in Anfu County of Jiangxi Province as test objects, this paper studied the effects of land use change on the soil organic carbon (SOC) pool and soil labile organic carbon (SLOC) contents. The soil organic carbon (SOC), microbial biomass carbon (MBC), hot- water extractable carbon (HWC), and readily oxidizable carbon (ROC) contents in the test lands were all in the order of PE>CL>SS>AL. As compared with those in AL, the SOC content, soil carbon stock, and soil labile organic carbon (SLOC) contents in the three forest lands all decreased with increasing soil depth, and had an obvious accumulation in surface soil. The proportions of different kinds of SLOC to soil total organic carbon differed markedly, among which, ROC had the highest proportion, while MBC had the smallest one. There existed significant relationships between SOC, MBC, HWC, and ROC. The MBC, HWC, and ROC contained higher content of active carbon, and were more sensitive to the land use change, being able to be used as the indicators for evaluating the soil quality and fertility in central Jiangxi Province.