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In desert habitats, sand burial is an important factor affecting germination of plant seeds and seedling growth. Xanthium spinosum has strong adaptability in arid desert areas, and is a common malignant invasive plant in Xinjiang, China. The effects of different sand burial depths on seed germination, seedling emergence, growth and biomass allocation were studied to provide a scientific basis for further control of X. spinosum. Six sand burial depths (1, 2, 3, 5, 7 and 9 cm) were established to explore the response of X. spinosum seed germination and seedling growth to sand burial. The first emergence time, peak emergence time, emergence rate, seedling growth height, biomass and biomass distribution of X. spinosum seeds was significantly different at sand burial depths (P < 0.05). The X. spinosum seeds had the highest emergence rate (71.5%) at 1 cm sand burial and the maximum seedling height (7.1 cm). As sand burial depth increased, the emergence rate and seedling height gradually decreased. Emergence rate (12.25%) and seedling height (2.9 cm) were lowest at 9 cm sand burial. The root length at 9 cm depth (13.6 cm) was significantly higher than that at other sand depths (P < 0.05). The sand burial depth affected the biomass accumulation and distribution of X. spinosum. As sand burial depth increased, the root biomass and rhizome ratio increased, and the most deeply buried seedlings allocated more biomass for root growth. The optimal sand burial depth for seed germination and seedling growth of X. spinosum was 1–3 cm, and high burial depth (5–9 cm) was not conducive to the germination and growth of X. spinosum seedlings. For prevention and control of X. spinosum, we suggest deeply ploughing crops before sowing to ensure X. spinosum seeds are ploughed into a deep soil layer. [ABSTRACT FROM AUTHOR]

Odorant-binding proteins (OBPs) play an important role in the sense of smell in parasitoid wasps, especially for locating hosts and mates. Clarifying the role of OBPs in information exchanges between parasitoid wasps and their environment is beneficial for understanding the sense of smell in parasitoid wasps. To this end, we cloned the OBPs, SsicOBP1 and SsicOBP2 (GenBank accession numbers: AKP80533.1 and AKP80534.1), of Scleroderma sichuanensis Xiao and then proceeded to conduct prokaryotic expression and qPCR analysis, and determine the binding capacity of SsicOBP1 and SsicOBP2 with 18 types of volatiles from Pinus massoniana Lambert using competitive binding (with 1-NPN as fluorescent probes). We found that SsicOBP1 and SsicOBP2 are expressed at high levels in the antennae of Scleroderma sichuanensis Xiao. Of the 18 types of P. massoniana volatiles, SsicOBP1 could bind effectively with ocimene (binding constant of 12.82 µM) and β-pinene (binding constant of 15.57 µM). SsicOBP2 could bind effectively with α-pinene (with a binding constant of 13.52 µM), ocimene (binding constant of 14.38 µM) and β-pinene (binding constant of 14.51 µM). From this, we could infer that SsicOBP1 and SsicOBP2 are general odorant-binding proteins, which play an important role in sensing plant volatiles. [ABSTRACT FROM AUTHOR]

A series of (2-benzoylethen-1-ol)-containing benzothiazine derivatives was synthesized, and their herbicidal activities were first evaluated. The bioassay results indicated that some of 3-benzoyl-4-hydroxy-2-methyl-2 H -1,2-benzothiazine-1,1-dioxide derivatives displayed good herbicidal activity in greenhouse testing, especially, compound 4w had good pre-emergent herbicidal activities against Brassica campestris , Amaranthus retroflexus and Echinochloa crusgalli even at a dosage of 187.5 g ha −1 . More importantly, compound 4w displayed significant inhibitory activity against Arabidopsis thaliana HPPD and was identified as the most potent candidate with IC 50 value of 0.48 μM, which is better than the commercial herbicide sulctrione (IC 50 = 0.53 μM) and comparable with the commercial herbicide mesotrione (IC 50 = 0.25 μM). The structure–activity relationships was studied and provided some useful information for improving herbicidal activity. The present work indicated that (2-benzoylethen-1-ol)-containing 1,2-benzothiazine motif could be a potential lead structure for further development of novel HPPD inhibiting-based herbicides. [ABSTRACT FROM AUTHOR]

This work described the fabrication of a gold nanoparticles/single-walled carbon nanotubes/glassy carbon electrode containing mono-6-thio-β-cyclodextrin (SH-β-CD) self-assembled monolayer (SH-β-CD/AuNPs/SWCNTs/GCE) and its application for electrochemical determination of methyl parathion (MP) pesticide in solution using square wave anodic stripping voltammetry (SWV) method. The SH-β-CD/AuNPs/SWCNTs nanohybrids had a three-dimensional porous nanostructure with large active surface area, and the SH-β-CD monolayer on AuNPs/SWCNTs surface could greatly enhance the sensitivity and selectivity in detecting MP pesticides. The SWV response of the MP on the SH-β-CD/AuNPs/SWCNTs/GCE was ca. 3.9 and 5.1 times that of MP on the SH-β-CD/AuNPs/GCE and AuNPs/SWCNTs/GCE, respectively. The sensor demonstrated a wide linear response range from 2.0–80.0 nM, with a lower detection limit of 0.1 nM (S/N = 3) using 180 s of preconcentration time. The interference experiments showed that other aromatic insecticide, such as, chlorpyrifos, 2,4-dDichlorophenoxy acetic acid, methamidophos, triazophos, parathion had little influence on the MP signal. The proposed sensor was further employed for detection of MP in the real environmental water sample. [ABSTRACT FROM AUTHOR]

Histone deacetylase 6 (HDAC6) has emerged as a critical regulator of many cellular pathways in tumors due to its unique structure basis and abundant substrate types. Over the past few decades, the role played by HDAC6 inhibitors as anticancer agents has sparked great interest of biochemists worldwide. However, they were less reported for gastric cancer therapy. In this paper, with the help of bioisosteric replacement, in-house library screening, and lead optimization strategies, we designed, synthesized and verified a series of 1,3-diaryl-1,2,4-triazole-capped HDAC6 inhibitors with promising anti-gastric cancer activities. Amongst, compound 9r displayed the best inhibitory activity towards HDAC6 (IC 50 = 30.6 nM), with 128-fold selectivity over HDAC1. Further BLI and CETSA assay proved the high affinity of 9r to HDAC6. In addition, 9r could dose-dependently upregulate the levels of acetylated α-tubulin, without significant effect on acetylated histone H3 in MGC803 cells. Besides, 9r exhibited potent antiproliferative effect on MGC803 cells, and promoted apoptosis and suppressed the metastasis without obvious toxicity, suggesting 9r would serve as a potential lead compound for the development of novel therapeutic agents of gastric cancer. [Display omitted] ● A novel series of 1,3-diaryl-1,2,4-triazole-capped HDAC6 inhibitors were designed and synthesized by the strategies of bioisosteric replacement, in-house library screening, and lead optimization. ● Compound 9r exhibited the best potency to HDAC6 (IC 50 = 30.6 nM), with 128-fold selectivity over HDAC1. ● Compound 9r displayed promising anti-gastric cancer activity without obvious toxicity. [ABSTRACT FROM AUTHOR]

In this paper, a series of thiosemicarbazone derivatives containing different aromatic heterocyclic groups were synthesized and the tridentate donor system of the lead compound was optimized. Most of the target compounds showed improved antiproliferative activity against MGC803 cells. SAR studies revealed that compound 5d displayed significant advantages in inhibition effect with an IC 50 value of 0.031 μM, and better selectivity between cancer and normal cells than 3-AP and DpC (about 15- and 5-fold improved respectively). Besides, compound 5d showed selective antiproliferative activity in not only other cancer cells but also different gastric cancer cell lines. In-depth mechanism studies showed that compound 5d could induce mitochondria-related apoptosis which might be related to the elevation of intracellular ROS level, and cause cell cycle arrest at S phase. Moreover, 5d could evidently suppress the cell migration and invasion by blocking the EMT (epithelial–mesenchymal transition) process. Consequently, our studies provided a lead optimization strategy of thiosemicarbazone derivatives which would contribute to discover high-efficiency and low-toxicity agents for the treatment of gastric cancer. Image 1 • The design and synthesis were based on lead optimization strategy. • 5d showed higher antiproliferative activity and lower toxicity than 3-AP and DpC. • 5d could induce cell apoptosis, and inhibit the migration and invasion of MGC803 cells. [ABSTRACT FROM AUTHOR]

Pheromone-binding proteins ( PBPs) play important roles in the information exchange between insect sexes, specifically in the process of transporting fat-soluble odour molecules from the external environment to olfactory receptors through the olfactory sensillum lymph. The PBP functions in this process may explain the sex pheromone identification mechanism used by insects, laying a theoretical foundation for the prevention and control of pests by interfering with olfactory recognition. In the present study, a PBP gene of Cyrtotrachelus buqueti ( Gen Bank accession number: KU845733) is cloned for prokaryotic expression. Using N-phenyl-1-naphthylamine as the fluorescent probe in a competitive binding assay, the ability of CbuqPBP1 to bind 12 sex pheromone analogues and three volatiles of Neosinocalamus affinis shoots is examined. Of the 12 C. buqueti sex pheromone analogues, dibutyl phthalate gives the greatest displacement (inhibitory constant value of 11.1 μ m), whereas the other sex pheromone components show much smaller displacements. Consistent with other PBPs, the three plant volatiles (linalool, benzaldehyde and indole) show only a limited displacement of CbuqPBP1. However, the binding abilities of 1 : 1 ratios of each of the three plant volatiles with dibutyl phthalate show increases of 62.3%, 65.1% and 51.7% over the binding abilities of the three plant volatiles alone. CbuqPBP1 has dual roles in the processes of sensing sex pheromones and plant volatiles. [ABSTRACT FROM AUTHOR]

Abstract: Camellia chekiangoleosa is an important species of genus Camellia. It provides high-quality edible oil and has great ornamental value. The flowers are big and red which bloom between February and March. Flower pigmentation is closely related to the accumulation of anthocyanin. Although anthocyanin biosynthesis has been studied extensively in herbaceous plants, little molecular information on the anthocyanin biosynthesis pathway of C. chekiangoleosa is yet known. In the present study, a cDNA library was constructed to obtain detailed and general data from the flowers of C. chekiangoleosa. To explore the transcriptome of C. chekiangoleosa and investigate genes involved in anthocyanin biosynthesis, a 454 GS FLX Titanium platform was used to generate an EST dataset. About 46,279 sequences were obtained, and 24,593 (53.1%) were annotated. Using Blast search against the AGRIS, 1740 unigenes were found homologous to 599 Arabidopsis transcription factor genes. Based on the transcriptome dataset, nine anthocyanin biosynthesis pathway genes (PAL, CHS1, CHS2, CHS3, CHI, F3H, DFR, ANS, and UFGT) were identified and cloned. The spatio-temporal expression patterns of these genes were also analyzed using quantitative real-time polymerase chain reaction. The study results not only enrich the gene resource but also provide valuable information for further studies concerning anthocyanin biosynthesis. [Copyright &y& Elsevier]