Proteomics analysis of kojic acid treated A375 human malignant melanoma cells

Although the toxicogenomics of kojic acid treated A375 human malignant melanoma cells has been elucidated, the proteomics of cellular response is still poorly understood. We performed proteomic analysis to investigate the anticancer effect of kojic acid on protein expression profile in A375 cells. A375 cells were treated with kojic acid at 8 microg/mL for 24, 48, and 72 h. With the use of 2-D PAGE and MALDI-Q-TOF MS and MS/MS analyses, proteomic profiles of A375 cells between control and kojic acid treatment were compared, and 30 differentially expressed proteins, containing 2 up-regulated proteins and 28 down-regulated proteins, were identified. Among these proteins, 17 isoforms of 5 identical proteins were observed and 11 chaperone proteins showed the high proportion of protein spots with 36.7% of total proteins. Bioinformatic tools were used to search for protein function and prediction of protein interaction. Sixteen differentially expressed proteins exhibited interaction network linked to the downstream regulations of p53 tumor suppressor and cell apoptosis, which may lead to suppress the melanogenesis and tumorigenesis of kojic acid treated A375 cells. In addition, GRP75, VIME and 2AAA were validated by Western blot analysis, whereas GRP75, 2AAA, HS90B, ENPL and KPYM were validated by RT-PCR. Therefore, these proteins play the important roles in cancer progression and may be potential biomarkers that are useful for diagnostic and therapeutic applications of malignant melanoma cancer.     

The PKC delta inhibitor, rottlerin, induces apoptosis of haematopoietic cell lines through mitochondrial membrane depolarization and caspases' cascade

Rottlerin is a widely selective protein kinase C delta (PKCdelta) inhibitor isolated from Mallotus philippinensis. It shown to be effective against several human tumor cell lines and in potentiating chemotherapy-induced cytotoxcicity. Using the trypan blue exclusion assay, we demonstrated that rottlerin reduced the viability in a dose- and time-dependent manner of human leukemia HL60 cells, human acute T cell leukemia Jurkat cells and mouse macrophage RAW 264.7 cells. Rottlerin caused apoptosis and the apaptotic processing was inhibited by a caspase inhibitor, z-VAD-fmk, in these haematopoietic cells. The apoptosis-inducing activities were determined by nuclear condensation, sub-G1 appearance, DNA fragmentation, loss of mitochondrial membrane potential (Deltapsim), release of mitochondrial cytochrome c into cytoplasm and proteolytic activation of caspase 9 and 3. Expression of PKCdelta and Bcl-2 protein inhibited Deltapsim change and repressed cell death. These studies suggest that the cytotoxic effects of rottlerin through inhibition of PKCdelta cause mitochondrial dysfunction, cytochrome c release from mitochondria into cytoplasm and the activation of caspases' cascade.     

再论DG指数的性质与应用

密度-类群指数(DG指数)是为研究复杂的土壤动物群落多样性而创建的, 其理论基础是土壤动物群落中各类群互不干扰和互利的关系大于互相竞争的关系, 因而公式中各类群是互相独立、互不影响的.DG指数自1990年建立以来, 经作者及同行学者在不同地带、不同生态系统和不同级别的土壤动物群落研究中运用, 都获得良好的效果, 能真实地反映群落的多样性状况,显示出它具有广泛的适用性.用情景分析法(scenario analysis)探讨DG指数与Shannon-Wiener多样性指数(H')的预期效果, 结果显示, 当群落间种数差和均匀度(J)差为正负相反的数值时, Shannon-Wiener指数与DG指数不一致.文中还对土壤动物群落多样性的概念、性质及指数适用性进行了讨论, 认为土壤动物群落在客观上不存在均匀的数量分布, 把"均匀度"看作是多样性的重要指标是不适宜的.DG指数虽然没有直接包含许多信息, 但能在广泛的情况下经得起检验, 因而具有重要的应用价值.     

Housekeeping genes in cancer: normalization of array data

Biological maintenance of cells under variable conditions should affect gene expression of only certain genes while leaving the rest unchanged. The latter, termed "housekeeping genes," by definition must reflect no change in their expression levels during cell development, treatment, or disease state anomalies. However, deviations from this rule have been observed. Using DNA microarray technology, we report here variations in expression levels of certain housekeeping genes in prostate cancer and a colorectal cancer gene therapy model system. To highlight, differential expression was observed for ribosomal protein genes in the prostate cancer cells and beta-actin in treated colorectal cells. High-throughput differential gene expression analysis via microarray technology and quantitative PCR has become a common platform for classifying variations in similar types of cancers, response to chemotherapy, identifying disease markers, etc. Therefore, normalization of the system based on housekeeping genes, such as those reported here in cancer, must be approached with caution.     

典型生境巨菌草根内生固氮菌的群落多样性

【目的】探究不同生境巨菌草内生固氮菌群落组成多样性及其分异规律。【方法】采用高通量测序固氮酶nif H标靶基因方法,研究了我国6个典型地区的巨菌草内生固氮菌群,包括福建闽侯县、新疆墨玉县、内蒙古阿拉善左旗、青海贵德县、甘肃安定区、海南那大镇,结合地理气候因子统计,分析了固氮菌多样性的环境驱动机制。【结果】共获得64122条nif H基因的有效序列,640个OTUs,归属于6个门、10个纲、17个目、24个科、33个属和39个种。不同地区巨菌草中优势内生固氮菌群的种类和丰度存在较大的差异。在门水平上,福州闽侯县、甘肃安定区、新疆墨玉县、内蒙古阿拉善左旗和青海贵德县5个地区的优势菌门均为变形菌门,海南那大镇的优势菌门为变形菌门和蓝藻菌门;属水平上,不同地区巨菌草最优势内生固氮菌类群分别为:福州闽侯县(变形菌门中未定属,80.56%);新疆墨玉县(变形菌门中未定属,33.14%);内蒙古阿拉善左旗(变形菌门中未定属,76.23%);甘肃安定区(α-变形菌纲中的未定属,53.78%);海南那大镇(变形菌门中未定属,38.37%);青海贵德县(变形菌门中未定属,46.12%)。Alpha多样性和Beta多样性分析表明,不同地区巨菌草内生固氮菌群落的多样性存在较大的差异,海南那大镇样本中巨菌草各类内生固氮菌群的多样性及丰富度最高,福建闽侯县样本中巨菌草各类内生固氮菌群的多样性及丰富度最低。典范对应分析(CCA)结果表明,年均降雨量和年均气温是影响巨菌草内生固氮菌群变化的主要因素,其次是土壤有机质、土壤全氮和土壤p H。【结论】不同地区巨菌草内生固氮菌群落的组成及丰度存在着较大的差异,海南那大镇巨菌草内生固氮菌群的种类及相对丰度较高,本研究可为巨菌草内生固氮菌群的资源开发及其固氮微生物肥料的菌种选育和生产应用提供理论支持。     

海南地区与环渤海湾美人鱼发光杆菌美人鱼亚种水产动物分离株的表型与遗传特征分析

美人鱼发光杆菌美人鱼亚种(Photobacterium damselae subsp.damselae,PDD)是一种广泛分布于海洋环境内的重要病原菌,可导致多种海洋生物患病死亡,近年来在我国不同养殖区域内均有发现和报道.[目的]通过生理代谢表型、毒力基因分布和分子遗传分析,系统比较我国海南地区和环渤海湾不同株系PDD...     

Evaluation of protocols used in 2-d electrophoresis for proteome analysis of young rice caryopsis

In order to obtain a high-resolution electrophorogram of rice young panicle proteome, we evaluated various protocols commonly used in two-dimensional (2D) polyacrylamide gel electrophoresis (PAGE) of proteins, including gel staining protocol, pH range of immobilized pH gradient (IPG) strips and sample loading quantity. Results showed that a silver staining protocol using sensitized solution containing glacial acetic acid, sodium acetate and sodium thiosulfate (reported by Heukeshoven and Dernick in 1988) and a Coomassie Brilliant Blue staining method using solution containing G-250, ammonium sulfate and phosphoric acid (reported by Pink et al in 2010) demonstrated the superior staining effect. In addition, we also showed that higher resolution was achieved when IPG gel strip with pH range of 5-8 was used, compared to that with pH range of 4-7. Finally, the optimal loading quantity was determined as 130 μg using the 17 cm-long nonlinear IPG strip with pH 5-8 in combination with the silver nitrate staining protocol. The evaluated results would be helpful in proteome analysis of young rice caryopsis.     

黄芪对镉致大鼠睾丸支持细胞超微结构及波形蛋白、E-钙粘蛋白表达改变的保护作用

目的 探讨黄芪对镉致大鼠睾丸支持细胞损伤的保护作用.方法 21只成年雄性SD大鼠随机分成镉组(0.1％氯化镉腹腔内注射,1mg/Kg体重/天,5天/周,处理后1、2、3、4周取材)、镉加黄芪组(注射氯化镉的同时注射黄芪,10g/Kg体重/天,5天/周,处理后2、4周取材)和对照组(腹腔内注射等量生理盐水).睾丸取材作光镜、免疫组织化学染色和图像分析及超微结构观察.结果 光镜H.E染色对照组支持细胞核不规则,染色浅,核仁明显,镉处理后胞浆内有空泡形成,镉加黄芪组支持细胞未见明显改变.对照组波形蛋白阳性产物在支持细胞靠近基室腔的胞浆中表达,E-钙粘蛋白阳性产物则主要定位于生精上皮近腔室的支持细胞和部分生精细胞胞浆中.镉处理后支持细胞胞浆中波形蛋白和E-钙粘蛋白阳性产物表达的平均光密度值均明显降低(P＜0.05),镉加黄芪组阳性产物表达虽较对照组减弱但明显高于相应镉组(P＜0.05).镉处理组支持细胞胞质特化区和紧密连接破坏,镉加黄芪组支持细胞超微病变较相应镉组为轻.结论 镉降低大鼠睾丸支持细胞波形蛋白和E-钙粘蛋白的表达并造成支持细胞的超微结构损伤,黄芪具有较好的保护效果.     

Dianyuea gen. nov. (Salicaceae: Scyphostegioideae) from southwestern China

Dianyuea C. Shang, S. Liao & Z. X. Zhang, a new monotypic genus of Salicaceae based on Flacourtia turbinata H. J. Dong & H. Peng, is described and illustrated. Morphologically, Dianyuea differs from Flacourtia Comm. ex L'Hér. by having six connate stamens, basal placentation and lobed seed appendages. All those features indicate that Dianyuea is allied with Scyphostegia Stapf. A molecular phylogenetic analysis using plastid trnL‐F, matK, and rbcL sequence data for representatives of 16 genera in Salicaceae s.l. shows that Dianyuea is sister to Scyphostegia. The new combination Dianyuea turbinata (H. J. Dong & H. Peng) C. Shang, S. Liao & Z. X. Zhang is proposed.