Phosphorylated TandeMBP: A unique protein substrate for protein phosphatase assay

To analyze a variety of protein phosphatases, we developed phosphorylated TandeMBP (P-TandeMBP), in which two different mouse myelin basic protein isoforms were fused in tandem, as a protein phosphatase substrate. P-TandeMBP was prepared efficiently in four steps: (1) phosphorylation of TandeMBP by a protein kinase mixture (Ca²⁺/calmodulin-dependent protein kinase Iδ, casein kinase 1δ, and extracellular signal-regulated kinase 2); (2) precipitation of both P-TandeMBP and protein kinases to remove ATP, Pi, and ADP; (3) acid extraction of P-TandeMBP with HCl to remove protein kinases; and (4) neutralization of the solution that contains P-TandeMBP with Tris. In combination with the malachite green assay, P-TandeMBP can be used to detect protein phosphatase activity without using radioactive materials. Moreover, P-TandeMBP served as an efficient substrate for PPM family phosphatases (PPM1A, PPM1B, PPM1D, PPM1F, PPM1G, PPM1H, PPM1K, and PPM1M) and PPP family phosphatase PP5. Various phosphatase activities were also detected with high sensitivity in gel filtration fractions from mouse brain using P-TandeMBP. These results indicate that P-TandeMBP might be a powerful tool for the detection of protein phosphatase activities.     

Effects of heat and drought stress on post‐illumination bursts of volatile organic compounds in isoprene‐emitting and non‐emitting poplar

Over the last decades, post‐illumination bursts (PIBs) of isoprene, acetaldehyde and green leaf volatiles (GLVs) following rapid light‐to‐dark transitions have been reported for a variety of different plant species. However, the mechanisms triggering their release still remain unclear. Here we measured PIBs of isoprene‐emitting (IE) and isoprene non‐emitting (NE) grey poplar plants grown under different climate scenarios (ambient control and three scenarios with elevated CO₂ concentrations: elevated control, periodic heat and temperature stress, chronic heat and temperature stress, followed by recovery periods). PIBs of isoprene were unaffected by elevated CO₂ and heat and drought stress in IE, while they were absent in NE plants. On the other hand, PIBs of acetaldehyde and also GLVs were strongly reduced in stress‐affected plants of all genotypes. After recovery from stress, distinct differences in PIB emissions in both genotypes confirmed different precursor pools for acetaldehyde and GLV emissions. Changes in PIBs of GLVs, almost absent in stressed plants and enhanced after recovery, could be mainly attributed to changes in lipoxygenase activity. Our results indicate that acetaldehyde PIBs, which recovered only partly, derive from a new mechanism in which acetaldehyde is produced from methylerythritol phosphate pathway intermediates, driven by deoxyxylulose phosphate synthase activity.     

Design,green synthesis and pharmacological evaluation of novel 5,6-diaryl-1,2,4-triazines bearing 3-morpholinoethylamine moiety as potential antithrombotic agents*

The aim of this research work was to investigate a series of novel 5,6-diaryl-1,2,4-triazines (3a–3q) containing 3-morpholinoethylamine side chain, and to address their antiplatelet activity by in vitro, ex vivo and in vivo methods. All compounds were synthesized by environment benign route and their structures were unambiguously confirmed by spectral data. Compounds (3l) and (3m) were confirmed by their single crystal X-ray structures. Out of all the synthesized compounds, 10 were found to be more potent in vitro than aspirin; six of them were found to be prominent in ex vivo assays and one compound (3d) was found to have the most promising antithrombotic profile in vivo. Moreover, compound (3d) demonstrated less ulcerogenicity in rats as compared to aspirin. The selectivity of the most promising compound (3d) for COX-1 and COX-2 enzymes was determined with the help of molecular docking studies and the results were correlated with the biological activity.     

Pou4f2‐GFP knock‐in mouse line: A model for studying retinal ganglion cell development

Pou4f2 acts as a key node in the comprehensive and step‐wise gene regulatory network (GRN) and regulates the development of retinal ganglion cells (RGCs). Accordingly, deletion of Pou4f2 results in RGC axon defects and apoptosis. To investigate the GRN involved in RGC regeneration, we generated a mouse line with a POU4F2‐green fluorescent protein (GFP) fusion protein expressed in RGCs. Co‐localization of POU4F2 and GFP in the retina and brain of Pou4f2‐GFP/+ heterozygote mice was confirmed using immunofluorescence analysis. Compared with those in wild‐type mice, the expression patterns of POU4F2 and POU4F1 and the co‐expression patterns of ISL1 and POU4F2 were unaffected in Pou4f2‐GFP/GFP homozygote mice. Moreover, the quantification of RGCs showed no significant difference between Pou4f2‐GFP/GFP homozygote and wild‐type mice. These results demonstrated that the development of RGCs in Pou4f2‐GFP/GFP homozygote mice was the same as in wild‐type mice. Thus, the present Pou4f2‐GFP knock‐in mouse line is a useful tool for further studies on the differentiation and regeneration of RGCs.     

GENE SILENCING BY PARENTAL RNA INTERFERENCE IN THE GREEN RICE LEAFHOPPER,Nephotettix cincticeps (HEMIPTERA: CICADELLIDAE)

RNA interference (RNAi) has been widely used for investigating gene function in many nonmodel insect species. Parental RNAi causes gene knockdown in the next generation through the administration of double‐strand RNA (dsRNA) to the mother generation. In this study, we demonstrate that parental RNAi mediated gene silencing is effective in determining the gene function of the cuticle and the salivary glands in green rice leafhopper (GRH), Nephotettix cincticeps (Uhler). Injection of dsRNA of NcLac2 (9 ng/female) to female parents caused a strong knockdown of laccase‐2 gene of first instar nymphs, which eventually led to high mortality rates and depigmentation of side lines on the body. The effects of parental RNAi on the mortality of the nymphs were maintained through 12–14 days after the injections. We also confirmed the effectiveness of parental RNAi induced silencing on the gene expressed in the salivary gland, the gene product of which is passed from instar to instar. The parental RNAi method can be used to examine gene function by phenotyping many offspring nymphs with injection of dsRNA into a small number of parent females, and may be applicable to high‐efficiency determination of gene functions in this species.     

Horticultural mineral oil influences Plum pox virus transmission by Myzus persicae

The residual activity of horticultural mineral oil (HMO) on the ability of green peach aphids, Myzus persicae (Sulzer), (GPA) to transmit Plum pox virus (PPV) to peach was measured by infection rates of detached leaves from plants sprayed with either HMO or water as a control that were inoculated using transfer of 25 viruliferous aphids per leaf at 0, 2, 4, 7, 9, 11 and 14 days after treatment (DAT). Persistent effects of HMO residue on the probing and feeding behaviours of GPA were also monitored with the electrical penetration graph (EPG) system. For glasshouse‐grown peach seedlings, the residual activity of HMO reduced PPV infection rates by more than 58% for up to 4 DAT following an initial reduction of approximately 81%. EPG recordings of GPA feeding behaviour showed that HMO significantly delayed first feeding probes and first intracellular punctures by more than 50 min without changing the ensuing stylet penetration behaviour. Applying HMO reduced virus infection rates for up to a week depending on the environmental conditions. EPG monitoring of aphid probing showed that HMO reduced the mean duration and mean number of potential drop (PD) phase feeding occurrences, compared with the water control. A reduction in the PD that has been shown to be related to the transmission of non‐persistently transmitted viruses may partly explain the reduction in PPV infection rates.     

Quirks of dye nomenclature. 6. Malachite green

Malachite green was discovered independently by two researchers in Germany in the 19^th century and found immediate employment as a dye and a pigment. Subsequently, other uses, such as staining biological specimens, emerged. A much later application was the control of fungal and protozoan infections in fish, for which the dye remains popular, although illegal in many countries owing to a variety of toxicity problems. In solution, malachite green can exist as five different species depending on the pH. The location of the positive charge of the colored cation on a carbon atom or a nitrogen atom is still debated. The original names of this dye, and their origins, are briefly surveyed.     

基于遥感技术的城市下垫面参数与热环境关系的研究——以北京市朝阳区为例

城市热岛（UHI）不仅直接关系到城市人居环境质量和居民健康状况,同时还对城市能源消耗、生态系统过程演变、生物物候以及城市经济可持续发展有着深远的影响。以北京市朝阳区2002—2017年夏季4期Landsat系列遥感影像为数据,采用大气反演法,对15年间朝阳区城市地表温度（LST）时空变化进行分析,发现15年间朝阳区城市热岛比例指数上升迅速,热岛效应逐年加剧。进一步研究表明,城市地表温度与归一化植被指数（NDVI）及归一化建筑指数（NDBI）密切相关：地表温度与NDBI正相关,NDBI指数每升高0.1,地表升温0.79~2.37°C;与NDVI指数负相关,NDVI指数每提高0.1,地表降温0.4~0.77°C。本研究可为城市规划建设与城市绿地营建提供科学具体的参考指导依据,并促进生态可持续发展与人居环境改善。