基于文献计量学核盘菌研究现状及趋势分析

核盘菌是当今世界上最难防治的农业植物病原真菌之一,对植物生产危害极大,核盘菌的致病性研究备受国内外专家、学者的关注。本文运用文献计量学方法,统计2002-2017年间SCIE数据库收录的相关核盘菌研究文献1 972篇,通过对论文产出数量和被引次数进行数据分析,综合考量论文的学术影响力,全面反映目前世界核盘菌研究现状及发展态势。核盘菌研究领域科研论文数量呈上升趋势,美国、中国、加拿大是核盘菌研究领域的主要发文国家。Plant Disease和European Journal of Plant Pathology是核盘菌研究领域发文的主要刊源,我国核盘菌相关研究文献数量近年来增长迅速,华中农业大学、中国农业科学院、南京农业大学等是我国核盘菌研究领域科研实力较强的机构。把握时机,加强科研国际合作与交流,增加论文的学术影响力是我国今后的发展方向。     

Role of TLR4-TRPC6 in LPS-induced NF-κB P65 expression and nuclear translocation in airway epithelial 16HBE cells

AIM: To investigate the role of Toll-like receptor 4 (TLR4) and transient receptor potential channel 6 (TRPC6) signaling pathway in lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) P65 expression and nuclear translocation in airway epithelial cells (16HBE) for supplementing the mechanism for airway inflammation. METHODS: After stimulating the 16HBE cells with LPS at 1 mg/L for 0, 0.5, 2, 6, 12 and 24 h, the expression of NF-κB P65 at mRNA and protein levels in the 16HBE cells were determined by RT-PCR and Western blot respectively, and the nuclear translocation of NF-κB P65 was detected by immunocytochemical staining method. The effects of TLR4 inhibitor CLI-095 at 5 μmol/L and TRPC6 agonist Hyp9 at 10 μmol/L on LPS (1 mg/L)-induced NF-κB P65 expression and nuclear translocation in the 16HBE cells were determined by RT-PCR, Western blot and immunocytochemical staining. RESULTS: LPS increased the mRNA and protein expression of NF-κB P65 and nuclear translocation in the 16HBE cells(P<0.05). TLR4 inhibitor CLI-095 reduced the mRNA and protein expression of NF-κB P65 and nuclear translocation induced by LPS, while Hyp9 enhanced the mRNA and protein expression of NF-κB P65 and nuclear translocation induced by LPS in the 16HBE cells(P<0.05). CONCLUSION: LPS induces the expression and nuclear translocation of NF-κB P65 in the 16HBE cells via TLR4-TRPC6 signaling pathway.     

Knockdown of HMGA2 gene inhibits TGF-β1-induced human embryonic lung fibroblast growth and collagen synthesis

AIM: To investigate the effects of high mobility group A2(HMGA2) gene knockdown on the cell viability, apoptosis, collagen synthesis and oxidative stress of human embryonic lung fibroblast (HELF) induced by transforming growth factor-β1 (TGF-β1). METHODS: The HELF were divided into blank group, TGF-β1 group,negative control (NC) group and HMGA2 siRNA(si-HMGA2) group. The protein levels of HMGA2, AKT and p-AKT were determined by Western blot. The cell viability and apoptotic rate was analyzed by MTT assay and flow cytometry,respectively. The mRNA expression of collagen I (COL-Ⅰ) and COL-Ⅲ was detected by RT-qPCR. DCFH-DA was used to detect the content of reactive oxygen species (ROS). RESULTS: Compared with blank group, the protein levels of HMGA2 and p-AKT, the cell viability, the mRNA expression of COL-Ⅰ and COL-Ⅲ in TGF-β1 group were significantly increased, but the apoptotic rate and ROS level were significantly decreased (P<0.05). Compared with TGF-β1 group, the protein levels of HMGA2 and p-AKT, the cell viability, the mRNA expression of COL-Ⅰ and COL-Ⅲ in si-HMGA2 group were significantly decreased, but the apoptotic rate and ROS level were significantly increased (P<0.05). CONCLUSION: Knockdown of HMGA2 gene expression decreases the viability and collagen synthesis, and promotes apoptosis and ROS production of human embryonic lung fibroblasts induced by TGF-β1. The mechanism may be related to down-regulation of PI3K/AKT signaling pathway.     

Development of a reverse-transcription loop-mediated isothermal amplification assay to detect avian influenza viruses in clinical specimens

In recent years, the avian influenza has brought not only serious economic loss to the poultry industry in China but also a serious threat to human health because of the avian influenza virus(AIV) gene recombination and reassortment. Until now, traditional RT-PCR, fluorescence RT-PCR and virus isolation identification have been developed and utilized to detect AIV, but these methods require high-level instruments and experimental conditions, not suitable for the rapid detection in field and farms. In order to develop a rapid, sensitive and practical method to detect and identify AIV subtypes, 4 specific primers to the conserved region of AIV M gene were designed and a loop-mediated isothermal amplification(RT-LAMP) method was established. Using this method, the M gene of H1–H16 subtypes of AIV were amplified in 30 min with a water bath and all 16 H subtypes of AIV were able to be visually identified in presence of fluorescein, without cross reaction with other susceptible avian viruses. In addition, the detection limit of the common H1, H5, H7, and H9 AIV subtypes with the RT-LAMP method was 0.1 PFU(plaque-forming unit), which was 10 times more sensitive than that using the routine RT-PCR. Further comparative tests found that the positivity rate of RT-LAMP on detecting clinical samples was 4.18%(14/335) comparing with 3.58%(12/335) from real-time RT-PCR. All these results suggested that the RT-LAMP method can specifically detect and identify AIV with high sensitivity and can be considered as a fast, convenient and practical method for the clinic test and epidemiological investigation of AIV.     

Looking back on development and disaster‐related displacement and resettlement,anticipating climate‐related displacement in the Asia Pacific region

The realisation that climate change might necessitate resettlement of people displaced initially raised interest in the experience of development‐forced displacement and resettlement (DFDR). Looking back, in 1980 the first international policy on involuntary resettlement was approved to address perceived weaknesses in state property and expropriation law to safeguard people in the way of development projects. Since then international policy and praxis have brought global attention to developmentally displaced people but have not guaranteed them an effective safeguard. Recently, renewed attention has focussed on state legal and governance frameworks substantively and procedurally. Identifying four key policy objectives that resonate with climate change displacement I analyse their treatment in a data base of DFDR laws and regulations from 40 Asia Pacific states. This analysis finds overall little legal congruence. Innovative new formulations in some Asian state laws address recent public criticisms and research findings, but mostly are yet to demonstrate positive outcomes for displaced people. Pacific states increasingly abandon expropriation law to negotiate lease terms for public infrastructure projects with customary landowners that do not extinguish customary title. Any laws governing climate change relocations must protect rights, livelihoods, well‐being, inclusive decision‐making and community initiatives with procedures whilst not relinquishing climate‐change‐reducing action.     

利用基因拆分技术培育耐草甘膦转基因水稻的研究

耐除草剂转基因水稻基因飘流可能产生的环境安全问题是人们关注的焦点之一,并已成为耐除草剂转基因水稻能否在我国生产上发挥效益的限制因素。基因拆分技术能够有效地控制转基因目标性状飘流,为培育耐除草剂转基因水稻提供新的途径和思路。本研究将耐除草剂基因G2-aroA拆分成N端(EPSPSn,1～295aa)和C端(EPSPSc,296～435aa),分别与SspDnaE蛋白内含肽的N端(Intein-N)和C端(Intein-C)连接形成融合基因EPSPSn-In与Ic-EPSPSc,并分别通过农杆菌介导法转入受体材料中花11。Southern杂交证明转基因水稻En-12和Ec-22中外源基因为单拷贝插入。侧翼序列分析证明转基因水稻En-12和Ec-22中外源基因分别插入第2和第6染色体。利用四引物法筛选出转基因水稻En-12和Ec-22的纯合系,并通过有性杂交获得同时含有EPSPSn-In与Ic-EPSPSc的转基因水稻En×Ec。草甘膦抗性分析发现,单独含有1个基因片段的转基因水稻En-12和Ec-22不具有耐受草甘膦特性,而同时含有2个基因片段的转基因水稻En×Ec具有耐受草甘膦的特性,说明拆分后的2个蛋白片段在intein的介导下重新组装成完整有功能蛋白,并赋予转基因水稻耐受草甘膦的特性。转基因水稻En×Ec与含有完整G2-aroA转基因水稻G2-6相比,其耐受草甘膦的能力有所下降,但能够满足生产需求。本研究结果为利用基因拆分技术培育转基因耐草甘膦水稻提供了科学依据,同时也为利用基因工程手段培育转基因杂交稻提供了新的技术平台。     

棉花中GhTFL1a和GhTFL1c基因的表达及启动子分析

从陆地棉中克隆了磷脂酰乙醇胺结合蛋白GhTFL1a和GhTFL1c基因,并对该基因进行表达分析、启动子预测和启动子活性研究。利用启动子分析软件PlantCARE预测得出,GhTFL1a启动子区域有脱落酸响应元件、干旱诱导的MYB结合位点和顶芽特异表达响应元件等;GhTFL1c启动子区域有乙烯响应元件、干旱诱导的MYB结合位点和水杨酸响应元件。因此,将pGhTFL1a和pGhTFL1c分别构建到启动子检测载体pBI121-GUS上形成融合表达载体,通过烟草瞬时转化检测得出这2个基因的启动子都具有活性。实时荧光定量PCR分析表明, GhTFL1a和GhTFL1c在光周期处理和不同材料的陆地棉(栽培种和半野生种)中表达模式呈相反趋势。GhTFL1a基因受脱落酸(abscisic acid, ABA)、水杨酸(salicylic acid, SA)和盐胁迫诱导,而GhTFL1c可以响应赤霉素(gibberellin, GA)、SA和ABA胁迫。研究结果初步表明,GhTFL1a和GhTFL1c可能参与了植物逆境胁迫脱落酸和水杨酸响应的调控,为在棉花中进一步阐明其功能奠定了基础。     

玉米开花期相关的Indeterminate domain(IDD)蛋白家族基因的鉴定

开花期是影响玉米产量的重要因子之一。Indeterminate1 (ID1)编码玉米Indeterminate domain (IDD)家族蛋白,是玉米开花期的重要调控因子。然而,其他玉米IDD蛋白家族基因及其生物学功能有待深入研究。本文利用生物信息学技术在玉米基因组中鉴定并分离了37个IDD家族基因,记作ZmIDD。表达分析发现这些ZmIDD基因在8个玉米组织中显示出多种表达模式。为进一步探讨ZmIDD基因在调控玉米开花期上的作用,检测了37个ZmIDD在172个自交系中的遗传多样性,发现35个ZmIDD基因在自交系间具有多态性,平均每个基因具有37.8个多态性位点。关联分析鉴定到包含ID1在内的7个ZmIDD基因在多个环境下与开花期性状显著关联。对Zm00001d020683基因2 kb的启动子区和600 bp编码区重测序,共鉴定到64个多态性位点。候选基因关联分析鉴定到2个启动子区的插入缺失(In/Del)位点与开花期显著关联,其中2个位点分别插入3 bp和2 bp的单倍型为一种提早开花的基因型。研究结果为玉米开花期相关基因的分离和利用研究提供了候选基因和选择靶点。     

花生AhPEPC1基因抑制表达的转基因后代转录组分析

磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvatecarboxylase,PEPC)是控制油料作物种子中蛋白质/油脂含量比率的一个关键酶。本研究检测了花生AhPEPC1基因抑制表达的转基因株系种子含油量,与非转基因花生相比,转基因花生种子含油量提高了5.7%～10.3%。利用转录组测序(RNA-Seq)技术分析花生中AhPEPC1基因的抑制表达是否影响其他基因的功能。结果表明,转录组分析筛选到110个基因差异表达,其中25个基因上调表达,85个基因表达下调。对110个差异表达基因进行了KEGG富集分析,其中有34个基因成功获得了KEGG注释,发现氨基酸的生物合成途径中有2个基因(Aradu.M0JX8,Aradu.FE0Z7)下调表达。利用荧光定量PCR分析了15个DEG(differential expressed gene)在非转基因对照和转基因花生种子中的表达情况,发现其趋势与转录组测序结果基本一致。研究结果可在一定程度上解析AhPEPC1基因调控花生种子含油量的分子机制。