A systematic study of North American Angelica species (Apiaceae) based on nrDNA ITS and cpDNA sequences and fruit morphology

Angelica is a taxonomically complex genus widespread throughout the North Temperate Zone. Previous phylogenetic studies of the genus have focused primarily on its East Asian species. The relationships among its North American members, the monophyly of these species, and the value of fruit morphology in circumscribing its taxa have yet to be examined. This study represents the most comprehensive sampling of Angelica to date (100 species) and includes all 26 species in North America. Relationships are inferred using Bayesian inference, maximum likelihood, and maximum parsimony analyses of ITS sequences and, for multiple accessions of each North American species, cpDNA ndhF-rpl32, rpl32-trnL, and psbM-psbD sequences. The fruit morphological characters examined were those considered phylogenetically important in East Asian Angelica. The results revealed that the North American species fell into three major clades: North American Angelica clade, Archangelica clade, and the Eurasian Angelica clade. Angelica dawsonii has affinities with Lomatium brandegeei. Fourteen species within the North American Angelica clade were strongly supported as monophyletic. Two paraphyletic species resulted in new combinations in A. lineariloba and A. venenosa. Conflict between the ITS-derived and cpDNA-derived phylogenies and the lack of resolution in portions of the trees may be due to chloroplast capture and rapid species radiation. Fruit morphology supported some interspecific relationships based on molecular data, and relationships revealed by ITS and cpDNA data were roughly in accordance with fruit classification type and geographic distribution region, respectively. A diagnostic key based on fruit morphology is provided for the identification of the North American Angelica taxa.     

Intracellular localization of type III-delivered Pseudomonas ExoS with endosome vesicles

ExoS (453 amino acids) is a bi-functional type III cytotoxin produced by Pseudomonas aeruginosa. Residues 96-219 include the Rho GTPase-activating protein (RhoGAP) domain, and residues 234-453 include the 14-3-3-dependent ADP-ribosyltransferase domain. Earlier studies also identified an N-terminal domain (termed the membrane localization domain) that comprises residues 51-77 and includes a novel leucine-rich motif that targets ExoS to the perinuclear region of cultured cells. There is limited information on how ExoS or other type III cytotoxins enter and target intracellular host proteins. Type III-delivered ExoS localized to both plasma membrane and perinuclear region, whereas ExoS(DeltaMLD) was localized to the cytosol. Plasma membrane localization of ExoS was transient and had a half-life of approximately 20 min. Type III-delivered ExoS co-immunoprecipitated 14-3-3 proteins and Rab9, Rab6, and Rab5. Immunofluorescence experiments showed that ExoS colocalized with Rab9, Rab6, and Rab5. Fluorescent energy transfer was detected between ExoS and 14-3-3 proteins but not between ExoS and Rabs proteins. Together, these results indicate that type III-delivered ExoS localizes on the host endosomes and utilizes multiple pathways to traffic from the plasma membrane to the perinuclear region of intoxicated host cells.     

Higher insulin, triglycerides, and blood pressure with greater trunk fat in Tanner 1 Chinese

Objective: The aims of this study were to investigate the body fat distribution pattern in prepubertal Chinese children and to investigate the relationship between central fat distribution and specific biomarkers of cardiovascular disease. Research Methods and Procedures: The study was conducted in an urban Mainland Chinese (Jinan, Shandong) sample of children using a cross‐sectional design. Pubertal status was determined by Tanner criteria. Measurements included weight, height, waist circumference, DXA measures of total body fat and trunk fat; fasting serum measures of glucose, insulin, triglyceride, cholesterol, high‐density lipoprotein‐cholesterol; and systolic and diastolic blood pressure. Multiple regression models were developed with the biomarkers of cardiovascular risk factor as the dependent variables, and adjustments were made for significant covariates, including sex, age, height, weight, waist circumference, total body fat, trunk fat, and interactions. Results: A total of 247 healthy prepubertal subjects were studied. After co‐varying for age, weight, height, and extremity fat (the sum of arm fat and leg fat), girls had greater trunk fat than boys (p < 0.0001, R² for model = 0.95). Insulin and triglyceride were positively related to central fat measured by DXA‐trunk fat (p < 0.05) but not related to the waist circumference. In the blood pressure model, waist circumference was a significant predictor of both systolic blood pressure and diastolic blood pressure, while DXA‐trunk fat was associated with diastolic blood pressure only. Significant interactions between sex and trunk fat, and sex and total fat, were found in relation to diastolic blood pressure. Discussion: In prepubertal Chinese children, greater trunk fat was significantly associated with higher insulin and triglyceride in boys and girls and was associated with higher diastolic blood pressure in boys only.     

Erwinia carotovora ssp. carotovora Infection Induced ＂Defense Lignin＂ Accumulation and Lignin Biosynthetic Gene Expression in Chinese Cabbage （Brassica rapa L. ssp. pekinensis）

Erwinia carotovora subsp, carotovora （Ecc） infects and causes soft rot disease in hundreds of crop species including vegetables, flowers and fruits. Lignin biosynthesis has been implicated in defensive reactions to injury and pathogen infection in plants. In this work, variations of lignin content and gene expression in the molecular interaction between Chinese cabbage and Ecc were investigated. H2O2 accumulation and peroxidase activity were detected by 3, 3＇- Dimethoxybenzidine staining at mocked and Ecc-inoculated sites of Chinese cabbage leafstalks. Klason lignin content in inoculated plants increased by about 7.84%, 40.37%, and 43.13% more than that of the mocked site at 12, 24 and 72 h after inoculation, respectively. Gas chromatography detected more p-coumaryl （H） and less coniferyl （G） and sinapyl （S） monolignins in leafstalks of Chinese cabbage. All three monomers increased in Ecc-infected leafstalks, and the Ecc-induced ＂defense lignin＂ were composed of more G and H monolignins, and less S monolignin. After searching the expressed sequence tags （EST） data of Chinese cabbage, 12 genes putatively encoding enzymes involved in lignin biosynthesis were selected to study their expression. All of these genes could be induced by mock inoculation and Ecc infection, while the gene expression lasted for several more hours in the infected samples than in mocked and untreated plants. Our results indicated that ＂defense lignin＂ was different from the developmental lignin in composition; G and S monolignins were significantly induced in plants in response to the soft rot Ecc; thus, lignin biosynthesis was differentially regulated and played a role in plant response to the soft rot Ecc.     

富贵草杀灭钉螺效应研究

以富贵草(Pachysandra terminalis Sieb.et Zucc.)(以下简称PT)为实验材料,采用开放式浸杀法研究其植物原粉及提取物(PT-Ⅰ)对钉螺的杀灭效果和对鱼类的毒性作用。结果表明PT原粉浓度为17.5 mg/L时,钉螺72 h死亡率为93.4%,120 h死亡率达100.0%;其24、72、120、168 h的LC50分别为42.28、7.20、4.20、3.17 mg/L。PT原粉浓度为75.0 mg/L时,经168 h鱼死亡率为0。使用浓度为35.0、17.5、8.75、4.38 mg/L的PT原粉,分别浸泡1、2、18、42 h时,抑制钉螺上爬率均达到100%。原粉经提取分离得到PT-Ⅰ组分,以1.40 mg/L的PT-Ⅰ组分分别浸杀钉螺24、48、72、96、120 h,钉螺死亡率分别为36.7%、73.3%、96.7%、96.7%、100.0%。表明PT具有很好的杀灭钉螺、抑制钉螺上爬效果,且对鱼毒性较低,是一种较有研究价值的灭螺植物。     

Two new antibacterial sesquiterpenoids from Centipeda minima

Two new guaiane-type sesquiterpene lactones, compounds 1 and 2, along with three known guaianolide- or pseudoguaianolides, were isolated from Centipeda minima (whole plant). Their structures were identified by spectroscopic and mass-spectrometric analyses. The configuration at C5 of the guaiane framework of 1 was rationalized by quantum-mechanical calculations (Table 2). All compounds were found to be active against eight different microbial pathogens (Table 3), with MIC values in the range of 6.25-100 microg/ml.     

人γ－精浆蛋白的亲和纯化及其糖基化分析

目的:从人精液中提纯γ-精浆蛋白并对其生物学特性进行鉴定。 方法:应用饱和硫酸铵法从小鼠腹水中纯化出抗γ-精浆蛋白的单克隆抗体E4B7,将其共价交联到CNBr-Sepharose4B上,制备成免疫亲和层析柱,用该层析柱亲和纯化经饱和硫酸铵粗提的精液标本。纯化产物分别用SDS-PAGE、Western-blot及ELISA进行生物学特性鉴定,最后经PNGase F、Endo-H酶消化后进行糖基化分析。结果:SDS-PAGE电泳表明纯化蛋白的相对分子量约为44KD,Western-blot及ELISA鉴定显示该蛋白可与抗γ-精浆蛋白的单抗E4B7特异性结合。对纯化蛋白无论是单用Endo-H酶消化,还是同时用Endo-H酶和PNGase F酶共同消化,消化产物电泳后相对分子量均降低到34KD左右,而单独用PNGase F酶消化后相对分子量没有改变。Western-blot及ELISA鉴定显示糖苷酶处理后的纯化蛋白仍可与单抗E4B7特异性结合。结论:成功纯化出N-糖基化形式的γ-精浆蛋白,这为下一步筛选人源化抗体奠定了纯的抗原基础。     

Targeting autophagic regulation of NFkappaB in HTLV-I transformed cells by geldanamycin: implications for therapeutic interventions

The IkappaB kinase (IKK)/NFkappaB signaling pathway plays an essential role in the development and survival of many types of cancers including adult T-cell leukemia (ATL) caused by the human T-cell leukemia virus type I (HTLV-I) infection. Accordingly, targeting NFkappaB provides an attractive strategy for cancer therapy. We recently found that specific inhibition of Hsp90 by geldanamycin (GA) results in autophagic degradation of IKK and NFkappaB-inducing kinase (NIK), an upstream kinase of IKK, and inactivation of NFkappaB in various cell lines. Here, we further report that GA inhibition of Hsp90 also led to IKK autophagic degradation and NFkappaB inhibition in both HTLV-transformed T cells and ATL-derived cell lines. Importantly, GA treatment led to efficient apoptosis of these malignant cells, whereas inhibition of autophagic degradation of IKK significantly ameliorated the cytotoxic effect of GA. These findings thus not only provide mechanistic insights into the tumor suppression function of autophagy and the anti-tumor activity of GA, but also suggest an immediate therapeutic strategy for ATL and other diseases associated with NFkappaB activation by targeting autophagic degradation of the central NFkappaB activating kinases.     

An unconventionally secreted effector from the root knot nematode Meloidogyne incognita,Mi-ISC-1, promotes parasitism by disrupting salicylic acid biosynthesis in host plants

Plant-parasitic nematodes need to deliver effectors that suppress host immunity for successful parasitism. We have characterized a novel isochorismatase effector from the root-knot nematode Meloidogyne incognita, named Mi-ISC-1. The Mi-isc-1 gene is expressed in the subventral oesophageal glands and is up-regulated in parasitic-stage juveniles. Tobacco rattle virus-induced gene silencing targeting Mi-isc-1 attenuated M. incognita parasitism. Enzyme activity assays confirmed that Mi-ISC-1 can catalyse hydrolysis of isochorismate into 2,3-dihydro-2,3-dihydroxybenzoate in vitro. Although Mi-ISC-1 lacks a classical signal peptide for secretion at its N-terminus, a yeast invertase secretion assay showed that this protein can be secreted from eukaryotic cells. However, the subcellular localization and plasmolysis assay revealed that the unconventional secretory signal present on the Mi-ISC-1 is not recognized by the plant secretory pathway and that the effector was localized within the cytoplasm of plant cells, but not apoplast, when transiently expressed in Nicotiana benthamiana leaves by agroinfiltration. Ectopic expression of Mi-ISC-1 in N. benthamiana reduced expression of the PR1 gene and levels of salicylic acid (SA), and promoted infection by Phytophthora capsici. The cytoplasmic localization of Mi-ISC-1 is required for its function. Moreover, Mi-ISC-1 suppresses the production of SA following the reconstitution of the de novo SA biosynthesis via the isochorismate pathway in the cytoplasm of N. benthamiana leaves. These results demonstrate that M. incognita deploys a functional isochorismatase that suppresses SA-mediated plant defences by disrupting the isochorismate synthase pathway for SA biosynthesis to promote parasitism.