25 research outputs found
Firmly anchored photosensitizer Chlorin e6 to layered double hydroxide nanoflakes for highly efficient photodynamic therapy in vivo
We covalently conjugate photosensitizer Chlorin e6 (Ce6) to polyethylene glycol modified layered double hydroxides and produce hybrid nanoflakes with excellentin vivophotodynamic therapeutic efficiency and safety profiles.</p
Convergence of the 26S proteasome and the REVOLUTA pathways in regulating inflorescence and floral meristem functions in Arabidopsis
The 26S proteasome is a large multisubunit proteolytic complex, regulating growth and development in eukaryotes by selective removal of short-lived regulatory proteins. Here, it is shown that the 26S proteasome and the transcription factor gene REVOLUTA (REV) act together in maintaining inflorescence and floral meristem (IM and FM) functions. The characterization of a newly identified Arabidopsis mutant, designated ae4 (asymmetric leaves1/2 enhancer4), which carries a mutation in the gene encoding the 26S proteasome subunit, RPN2a, is reported. ae4 and rev have minor defects in phyllotaxy structure and meristem initiation, respectively, whereas ae4 rev demonstrated strong developmental defects. Compared with the rev single mutant, an increased percentage of ae4 rev plants exhibited abnormal vegetative shoot apical and axillary meristems. After flowering, ae4 rev first gave rise to a few normal-looking flowers, and then flowers with reduced numbers of all types of floral organs. In late reproductive development, instead of flowers, the ae4 rev IM produced numerous filamentous structures, which contained cells seen only in the floral organs, and then carpelloid organs. In situ hybridization revealed that expression of the WUSCHEL and CLAVATA3 genes was severely down-regulated or absent in the late appearing ae4 rev primordia, but the genes were strongly expressed in top-layer cells of inflorescence tips. Double mutant plants combining rev with other 26S proteasome subunit mutants, rpn1a and rpn9a, resembled ae4 rev, suggesting that the 26S proteasome might act as a whole in regulating IM and FM functions
Overexpression of Saussurea involucrata dehydrin gene SiDHN promotes cold and drought tolerance in transgenic tomato plants.
Dehydrins are late embryogenesis abundant proteins that help regulate abiotic stress responses in plants. Overexpression of the Saussurea involucrata dehydrin gene SiDHN has previously been shown to improve water-use efficiency and enhance cold and drought tolerance of transgenic tobacco. To understand the mechanism by which SiDHN exerts its protective function, we transformed the SiDHN gene into tomato plants (Solanum lycopersicum L.) and assessed their response to abiotic stress. We observed that in response to stresses, the SiDHN transgenic tomato plants had increased contents of chlorophyll a and b, carotenoid and relative water content compared with wild-type plants. They also had higher maximal photochemical efficiency of photosystem II and accumulated more proline and soluble sugar. Compared to those wild-type plants, malondialdehyde content and relative electron leakage in transgenic plants were not significantly increased, and H2O2 and O2- contents in transgenic tomato plants were significantly decreased. We further observed that the production of stress-related antioxidant enzymes, including superoxide dismutase, ascorbate peroxidase, peroxidase, and catalase, as well as pyrroline-5-carboxylate synthetase and lipid transfer protein 1, were up-regulated in the transgenic plants under cold and drought stress. Based on these observations, we conclude that overexpression of SiDHN gene can promote cold and drought tolerance of transgenic tomato plants by inhibiting cell membrane damage, protecting chloroplasts, and enhancing the reactive oxygen species scavenging capacity. The finding can be beneficial for the application of SiDHN gene in improving crop tolerance to abiotic stress and oxidative damage
Insight into the Molecular Mechanism of Flower Color Regulation in <i>Rhododendron latoucheae</i> Franch: A Multi-Omics Approach
Rhododendron latoucheae Franch. (R. latoucheae) is a valuable woody plant known for its high ornamental value. While purple flowers are a distinct and attractive variant phenotype of R. latoucheae, the underlying mechanism regulating its flower color is still poorly understood. To investigate the molecular regulatory mechanism responsible for the variation in flower color, we selected plants with white-pink and purple petals as the object and conducted analyses of metabolites, key genes, and transcription factors associated with flower color. A combined metabolome–transcriptome analysis was performed, and the expression of key genes was subsequently verified through qRT-PCR experiments. The results of our study demonstrated a significant enrichment of differential metabolites in the flavonoid metabolic pathway. Changes in anthocyanin content followed the same trend as the observed flower color variations, specifically showing significant correlations with the contents of malvidin-3-O-glucoside, dihydromyricetin, gallocatechin, and peonidin-3-O-glucoside. Furthermore, we identified three key structural genes (F3GT1, LAR, ANR) and four transcription factors (bHLH130, bHLH41, bHLH123, MYB4) that are potentially associated with the biosynthesis of flavonoid compounds, thereby influencing the appearance of purple flower color in R. latoucheae
Fe1-xS/C nanocomposites from sugarcane waste-derived microporous carbon for high-performance lithium ion batteries
We report a novel strategy to collect microporous carbon from disposable sugarcane waste for lithium ion battery (LIB) applications. First boiled in water and ethanol and then calcined, the sugarcane waste successfully transforms into microporous carbon, delivering a specific capacity of 311 mA h g<small><sup>−1</sup></small> at 0.33C as a LIB anode material. For improved LIB performance, pyrrhotite-5T Fe<small><sub>1−<em>x</em></sub></small>S nanoparticles were uniformly dispersed and robustly attached to the scaffold of the microporous carbon using a novel sulfurization method. A remarkably ultrahigh capacity of 1185 mA h g<small><sup>−1</sup></small> (well beyond the theoretical value by 576 mA h g<small><sup>−1</sup></small>) was achieved after 200 charging/discharging cycles at a current density of 100 mA g<small><sup>−1</sup></small>, suggesting desirable synergetic effects between Fe<small><sub>1−<em>x</em></sub></small>S and microporous carbon which lead to a shortened lithium ion transportation path, enhanced conductivity and effective prevention of polysulfide dissolution. Our approach opens a convenient route for mass-producing sustainable, superior LIB electrodes from natural wastes that can substitute commercial graphite
Metabolome and transcriptome integration reveals insights into petals coloration mechanism of three species in Sect. Chrysantha chang
Background Sect. Chrysantha Chang, belonging to the Camellia genus, is one of the rare and precious ornamental plants distinguished by a distinctive array of yellow-toned petals. However, the variation mechanisms of petal color in Sect. Chrysantha Chang remains largely unclear. Methods We conducted an integrated analysis of metabolome and transcriptome to reveal petal coloration mechanism in three species, which have different yellow tones petals, including C. chuongtsoensis (CZ, golden yellow), C. achrysantha (ZD, light yellow), and C. parvipetala (XB, milk white). Results A total of 356 flavonoid metabolites were detected, and 295 differential metabolites were screened. The contents of 74 differential metabolites showed an upward trend and 19 metabolites showed a downward trend, among which 11 metabolites were annotated to the KEGG pathway database. We speculated that 10 metabolites were closely related to the deepening of the yellowness. Transcriptome analysis indicated that there were 2,948, 14,018 and 13,366 differentially expressed genes (DEGs) between CZ vs. ZD, CZ vs. XB and ZD vs. XB, respectively. Six key structural genes (CcCHI, CcFLS, CcDFR1, CcDFR2, CcDFR3, and CcCYP75B1) and five candidate transcription factors (MYB22, MYB28, MYB17, EREBP9, and EREBP13) were involved in the regulation of flavonoid metabolites. The findings indicate that flavonoid compounds influence the color intensity of yellow-toned petals in Sect. Chrysantha Chang. Our results provide a new perspective on the molecular mechanisms underlying flower color variation and present potential candidate genes for Camellia breeding
Green Synthesis of Bifunctional Fluorescent Carbon Dots from Garlic for Cellular Imaging and Free Radical Scavenging
Copolythiophene-Derived Colorimetric and Fluorometric Sensor for Lysophosphatidic Acid Based on Multipoint Interactions
3-Phenylthiophene-based water-soluble
copolythiophenes (<b>CPT9</b>) were designed for colorimetric
and fluorometric detection of lysophosphatidic
acid (LPA) based on electrostatic interaction, hydrophobic interaction,
and hydrogen bonding. Other negatively charged species gave nearly
no interference, and the detection limit reached to 0.6 μM,
which is below the requisite detection limits for LPA in human plasma
samples. The appealing performance of <b>CPT9</b> was demonstrated
to originate from the multipoint interaction-induced conformational
change of conjugated backbone and weakened electron transfer effect.
To our best knowledge, this is the first polythiophene based optical
sensor which displays emission peak red-shift followed with fluorescence
enhancement