A rapid and versatile combined DNA/RNA extraction protocol and its application to the analysis of a novel DNA marker set polymorphic between Arabidopsis thaliana ecotypes Col-0 and Landsberg erecta

Background  

Many established PCR-based approaches in plant molecular biology rely on lengthy and expensive methods for isolation of nucleic acids. Although several rapid DNA isolation protocols are available, they have not been tested for simultaneous RNA isolation for RT-PCR applications. In addition, traditional map-based cloning technologies often use ill-proportioned marker regions even when working with the model plant Arabidopsis thaliana, where the availability of the full genome sequence can now be exploited for the creation of a high-density marker systems.     

Progress of urinary exosome microRNAs in kidney diseases

Exosomes are extracellular vesicles that are actively released from all types of cells to various body fluids under the physiological and pathological conditions. It can be used as an intercellular signaling carrier by transferring specific components such as proteins, lipids and nucleic acids, which mediates the transmission of information between cells, thereby affecting the biological function of the recipient cells. Urinary exosomes are secreted by various cells in the urinary system and released into the urine. Recent studies have shown that changes of urinary exosome microRNAs can be used as biomarkers in kidney diseases for monitoring the changes of diseases and judging prognosis, and also have important value in the disease treatment. This article reviews the progress of urinary exosome microRNAs in kidney diseases.     

云芝子实体多糖(CVP)化学结构的研究(Ⅰ)

由化学方法揭示CVP是由多糖、核酸和蛋白质组成的混合物。用柱层析方法从CVP得到一个纯多糖A-1-2,组成它的单糖的摩尔比为GLu:Gal:Man:Xyl=9.67:1.64:1.00:0.88,用HPLC方法测得其分子量为9.3 ×10~3。     

黄皮种子脱水敏感性与核酸、蛋白质代谢的关系

黄皮种子发育晚期,胚内核酸和蛋白质合成能力增强,而花生种子发育晚期则呈下降趋势。脱水处理使生理成熟期黄皮胚核酸和蛋白质合成能力急剧下降,核酸水解酶活性增强。生物大分子代谢能力的变化是黄皮种子脱水敏感性的分子基础。     

Protocol: an improved and universal procedure for whole-mount immunolocalization in plants

Rapid advances in microscopy have boosted research on cell biology. However sample preparation enabling excellent reproducible tissue preservation and cell labeling for in depth microscopic analysis of inner cell layers, tissues and organs still represents a major challenge for immunolocalization studies. Here we describe a protocol for whole-mount immunolocalization of proteins which is applicable to a wide range of plant species. The protocol is improved and robust for optimal sample fixation, tissue clearing and multi-protein staining procedures and can be used in combination with simultaneous detection of specific sequences of nucleic acids. In addition, cell wall and nucleus labelling can be implemented in the protocol, thereby allowing a detailed analysis of morphology and gene expression patterns with single-cell resolution. Besides enabling accurate, high resolution and reproducible protein detection in expression and localization studies, the procedure takes a single working day to complete without the need for robotic equipment.     

乡村公园植物配置方法研究——以北碚静观乡村公园为例

从现状入手,探讨乡村公园植物选材、植物配置的基本原则和方法,分析其中存在的一些误区。并结合自身设计的北碚静观乡村公园中几个具有特色的景区特点,进一步探讨乡村公园如何通过植物配置来体现乡村的特色。     

番茄Cf-4-Avr4互作系统中信号转导基因的克隆与功能分析

 通过基因序列分析从抗叶霉病的番茄(含Cf-4基因) 中筛选出1个参与植物过敏反应的基因RGL (Resistance Gene L ike) 。采用酵母双杂交方法, 从番茄cDNA文库中筛选出两个与该基因的编码蛋白发生互作的蛋白, 分别命名为RGLIP-1和RGLIP-2 (RGL Interacting Protein) 。RGLIP-1全长291个氨基酸, 与类囊体内腔蛋白同源性较高, RGLIP-2全长248个氨基酸, 与拟南芥转导素高度同源。利用病毒诱导的基因沉默(Virus-Induced Gene Silencing, VIGS) 技术进行了基因功能分析。结果表明, 这两个互作蛋白参与了与植物抗病相关的过敏反应(Hypersensitive Response, HR) 。     

西瓜cDNA 表达文库构建及镰刀菌致病因子FonSIX6 互作蛋白的筛选和鉴定

 尖孢镰刀菌在与寄主的相互作用中分泌几个特定的富含半胱氨酸的小分子量蛋白（15.8 ~ 29.9 kD）进入木质部中启动致病力,被称为SIX（Secreted in xylem）蛋白。其中,SIX6蛋白是一个致病因子。西瓜专化型尖孢镰刀菌Fon（Fusarium oxysporum f. sp. niveurn）是引起西瓜枯萎病的病原真菌。为了解与FonSIX6存在相互作用的西瓜蛋白及其信号传导途径,克隆了FonSIX6基因,将FonSIX6的编码区与酵母GAL4的DNA结合功能区融合,构建成酵母诱饵蛋白表达载体pGBKT7-SIX6,进而转化到酵母菌株Y2H Gold中,经检测证实不具有毒性和自激活功能,可以用于酵母双杂交研究。同时,以国际上公认的抗枯萎病材料PI296341-FR构建酵母表达文库。采用酵母双杂交的方法,筛选到14个相互作用靶蛋白。分析筛选到的蛋白主要参与寄主的能量代谢、光合作用和基因表达调控,推测FonSIX6作用的靶位点主要是破坏寄主能量系统并影响光合作用,而寄主对其响应的方式是调控抗病基因的表达。     

A rapid and robust assay for detection of S-phase cell cycle progression in plant cells and tissues by using ethynyl deoxyuridine

Background  

Progress in plant cell cycle research is highly dependent on reliable methods for detection of cells replicating DNA. Frequency of S-phase cells (cells in DNA synthesis phase) is a basic parameter in studies on the control of cell division cycle and the developmental events of plant cells. Here we extend the microscopy and flow cytometry applications of the recently developed EdU (5-ethynyl-2'-deoxyuridine)-based S-phase assay to various plant species and tissues. We demonstrate that the presented protocols insure the improved preservation of cell and tissue structure and allow significant reduction in assay duration. In comparison with the frequently used detection of bromodeoxyuridine (BrdU) and tritiated-thymidine incorporation, this new methodology offers several advantages as we discuss here.     

Development of gene therapy in wound healing

The basic concept of gene therapy is to introduce a therapeutic gene into a cell, whose expression can improve to healing of wound. To achieve this goal, the suitable therapeutic gene has been selected and delivered into the reparative cell, which is becoming a focal point works about gene therapy in wound healing. There have been several different therapeutic genes and gene transfer strategies that have been used in models of wound healing. This article discusses several methods that have been used to deliver genes encoding growth factor proteins, stem cells into wounds and the advantages/disadvantages of each approach. We hope a safe vectors system to deliver the effectual transgene in wound healing.     

A nondestructive method for continuously monitoring plant growth

In the past, plant growth generally has been measured using destructive methods. This paper describes a nondestructive technique for continuously monitoring plant growth. The technique provides a means of directly and accurately measuring plant growth over both short and long time intervals. Application of this technique to the direct measurement of plant growth rates is illustrated using corn (Zea mays L.) as an example.     

Detection,cloning and expression of bone morphogenetic protein-1 from human osteosarcoma cell lines

AIM:To manufacture recombinant protein of the highly conserved domain in human bone morphogenetic protein-1(BMP-1) using gene engineering methods as antigen for making wide spectrum antibody to BMP-1.METHODS:We analyzed the gene sequences and protein structures of BMP-1 and its related proteins, and chose a highly conserved fragment as target gene. Total RNA was prepared from human osteosarcoma cell line Saos-2, then the target gene was amplified with RT-PCR. The PCR product was cloned into prokaryotic expression vector pMAL c2 to get recombinant vector BMP-1(322-588aa)-pMAL c2. After transforming the recombinant plasmid into DH5-alpha and screening, several prositive clones were got for sequencing. Finally the transformed cells was induced with IPTG to get fusion protein.RESULTS:The BMP-1 gene fragment was successfully cloned into vector pMAL c2, and was able to express efficiently with IPTG inducement. The amount of expressed fusion protein is about 66%-72% in total volume of bacterial proteins.CONCLUSIONS:The recombinant protein contains several key domains(2 CUB domains and 1 EGF domain), which are shared by BMP-1 and its related proteins. Specific wide spectrum antibody to human BMP-1 and its related proteins may be generated with this recombinant protein antigen.     

木本果树遗传转化研究进展

从遗传转化方法和影响遗传转化的因素两方面综述了木本果树遗传转化技术近年来的进展。木本果树遗传转化方法主要有农杆菌介导法和基因枪法;影响转化的因素主要从受体与再生系统、选择标记基因与转化细胞的筛选、培养方法与培养条件等方面进行论述。文章还归纳了导入目的基因并获得再生植株的木本果树种类,并对木本果树基因工程进展及展望进行了讨论。     

CELSS for advanced manned mission

An overview of the major concepts of Controlled Ecological Life Support System (CELSS) includes an identification of environmental factors, such as gravity levels, light levels, and growth volume, that influence the type of CELSS system that can be developed. Various plant growth systems are described together with their possible space applications. Life support functions performed by plants include food production, atmosphere regeneration, and water purification. Selected relationships between biological and physical-chemical life support techniques are considered as a part of these functions. Consumers in a CELSS may be humans, animals, or microorganisms, but nutritional, water, and atmosphere requirements of humans are emphasized in this report, as they are the primary requirement drivers for a CELSS design. The human role in waste generation is discussed as it affects plant nutrient availability. The role of waste management systems in recovering nutrients for plant growth and requirements for CELSS are defined for air, water, and food. Both physical and a biological nutrient recovery/waste disposal systems are examined. The separate subsystems of a CELSS are identified and discussed. Nutrient recovery, plant irradiation, automation, and facilities equipment and applications are reviewed with special attention to direct solar irradiation using fiber optics. These subsystems, along with other environmental control systems, such as thermal, humidity, and ventilation, are essential to plant growth in the space environment.     

苹果锚蛋白基因ANK家族生物信息学鉴定分析

 利用生物信息学方法对苹果ANK基因家族成员及分类鉴定,同时对其染色体定位、系统进化关系及芯片表达特性进行了分析。苹果MdANK家族包含351个基因,根据蛋白结构域差异分为16个类别,ANK-M类型最为庞大,有143个ANK蛋白;苹果的17条染色体均有ANK家族基因分布,其中第2条染色体上分布最多,有36个ANK基因。MdANK编码的蛋白在72 ~ 2 429个氨基酸范围内,等电点在4.30 ~ 11.13之间。芯片分析发现,在苹果果实成熟时期及砧木接穗互作过程中,多数MdANK基因的表达都有不同程度变化。     

High frequency, cell type-specific visualization of fluorescent-tagged genomic sites in interphase and mitotic cells of living Arabidopsis plants

Background  

Interphase chromosome organization and dynamics can be studied in living cells using fluorescent tagging techniques that exploit bacterial operator/repressor systems and auto-fluorescent proteins. A nuclear-localized Repressor Protein-Fluorescent Protein (RP-FP) fusion protein binds to operator repeats integrated as transgene arrays at defined locations in the genome. Under a fluorescence microscope, the tagged sites appear as bright fluorescent dots in living cells. This technique has been used successfully in plants, but is often hampered by low expression of genes encoding RP-FP fusion proteins, perhaps owing to one or more gene silencing mechanisms that are prevalent in plant cells.     

An improved method with a wider applicability to isolate plant mitochondria for mtDNA extraction

Background

Mitochondria perform a principal role in eukaryotic cells. Mutations in mtDNA can cause mitochondrial dysfunction and are frequently associated with various abnormalities during plant development. Extraction of plant mitochondria and mtDNA is the basic requirement for the characterization of mtDNA mutations and other molecular studies. However, currently available methods for mitochondria isolation are either tissue specific or species specific. Extracted mtDNA may contain substantial chloroplast DNA (cpDNA) and nuclear DNA (nDNA) and its end use efficiency can be reduced. Clearly, an effective mitochondria isolation method is warranted with wider applicability and with minimum contamination from cpDNA and nDNA.

Results

Here we reported an improved method for isolating mitochondria from dry wheat seeds and its extension to dead seeds, viable seeds, etiolated leaf tissue and several other plant species: oat, Arabidopsis, flax, and yellow mustard. The isolated mitochondria were successfully used to extract mtDNA with QIAamp DNA mini kit (Qiagen). The extracted mtDNA from the assayed samples of these species was intact in large quantity and showed little contamination from nDNA, cpDNA, RNA, and proteins. The mtDNA extracted from dead wheat seeds was also substantial, but more degraded and less intact when compared to those from viable seeds and other tissues.

Conclusion

The improved method was successfully applied to isolate mitochondria and extract mtDNA from several different tissues and plant species. The major advance in the improvement lies in its wider application with the same mitochondria extraction medium to different tissues and species. The improvement is significant, as it helps to widen the scope of future plant mitochondria research.

     

Poinsettia protoplasts - a simple, robust and efficient system for transient gene expression studies

ABSTRACT: BACKGROUND: Transient gene expression systems are indispensable tools in molecular biology. Yet, their routine application is limited to only few plant species and often requires substantial equipment and facilities. The high content of chloroplasts and chlorophyll can impede downstream applications of transformed cells from green plant tissue. RESULTS: We describe a fast and simple technique for the high-yield isolation and efficient transformation (>70%) of mesophyll-derived protoplasts from red leaves of the perennial plant Poinsettia (Euphorbia pulccherrima) for which no particular growth facilities or expensive equipment are needed. Poinsettia protoplasts display an astonishing robustness and can be employed in all commonly-used downstream applications, such as subcellular localisation (multi-colour fluorescence) or promoter activity studies. Due to a low abundance of chloroplasts or chromoplasts, problems encountered in other mesophyll-derived protoplast systems (particularly autofluorescence) are alleviated. Transgene expression is detectable within 90 min post-transformation and lasts over several days. CONCLUSIONS: The simplicity of isolation and transformation renders Poinsettia protoplasts an attractive system for transient gene expression experiments, including multicolour fluorescence, subcellular localisation and promoter activity studies. In addition, they offer hitherto unknown possibilities for anthocyan research and industrial applications.