植物细胞内产物释放行为研究进展

本文介绍了植物细胞培养中胞内产物释放的研究现状,包括：１、化学法：（１）有机溶剂法,（２）抗生素法,（３）蛋白质、溶血卵磷脂、脱乙酰几丁质,（４）去污剂、螯合剂;２．物理法：（１）渗透压冲击,（２）温度冲击,（３）电处理,（４）超声波处理、激光打孔,３、ｐＨ扰动及生物碱在胞内积累的两种机理。     

非洲菊的组织培养与快速繁殖

１植物名称非洲菊（Ｇｅｒｂｅｒａｊａｍｅｓｏｎｉｉ）,又名扶郎花。２材料类别无菌种子萌发的幼苗。３培养条件（１）种子萌发培养基：１／２ＭＳ＋０．７％琼脂（或脱脂棉）;（２）诱导分化培养基：ＭＳ＋６－ＢＡ１．５ｍｐ·Ｌ－１（单位下同）＋ＩＢＡ０．２;（３）芽增殖培养基：ＭＳ＋６－ＢＡ０．５;（４）生根培养基：ＭＳ＋ＮＡＡ２。上述（２）、（３）、（４）培养基内琼脂均为０．７％,蔗糖３％,ｐＨ５．８～６．０。培养条件为室温和自然光照,种子萌发前为暗培养。４生长与分化情况４．１萌发种子用纱布袋包装,无菌…     

第16卷总关键词索引

第１６卷总关键词索引阿蚊属（２）：９５Ｂ９５－８（３）：２７１白腹锦鸡（２）：１７８白鹇（２）：１９４；（４）：３５３白腰雨燕（４）：３８５保护生物学（３）：２８９蝙蝠蛾科（３）：２０７表皮生长因子（１）：４３比较（３）：２６３频谱分析（１）：７５濒...     

甜瓜的组织培养与快速繁殖

１植物名称甜瓜（Ｃｕｃｕｍｉｓｍｅｌｏ）品种“状元”。２材料类别顶芽、侧芽。３培养条件初代培养基：（１）ＭＳ＋６－ＢＡ０．２ｍｇ·Ｌ－１（单位下同）＋ＩＡＡ０．２。增殖培养基：（２）ＭＳ＋６－ＢＡＩ＋ＩＡＡ０．２。生根培养基：（３）Ｍｉｌｌｅｒ＋ＩＡＡ０．２;（４）Ｍｉｌｌｅｒ（无激素）。以上培养基ｐＨ均为５．８～６．０。琼脂浓度在（１）、（２）中为０．７％,在（３）、（４）中为０．６％;糖浓度在（１）、（２）中为３％,在（３）、（４）中为２％。培养温度均为（２５±３）℃,光照度２０００ｌｘ,光…     

第15卷关键词索引

第１５卷关键词索引白头鸭１５（３）：１９白蚁１５（２）：８５斑翅山鹑１５（４）：３７半翅目１５（３）：１斑点杂交试验１５（１）：８５斑羚１５（４）：４９斑腿蝗科１５（１）：２９蝙蝠蛾科１５（３）：５比较种群生态学１５（２）：３２Ｂ细胞１５（３）：８１...     

人血管内皮生因子受体配体结合域

利用ＰＣＲ技术,从人胎盘ｃＤＮＡ文库扩增出４个截短的人血管内皮生长因子受体（Ｆｌｔ－１）ｃＤＮＡ,分别含胞外第２、１－２、２－３、１－３个环,应用酵母双杂交系统对Ｆｌｔ－１的配体结合域进行了研究,结果表明不仅其胞外１－３环能与ｈＶＥＧＦ１６５结合,比其更小的片段２－３环也具有与配体结合的能力。进一步构建了重组表达质粒ｐＰＩＣ９Ｋ／Ｆｌｔ－１（１－３）和ｐＰＩＣ９Ｋ／Ｆｌｔ－１（２－３）,转化Ｐｉｖ     

环境对杂交水稻胞质及核质互作遗传表现的影响.不同N素下不育…

研究结果表明,水稻不育胞质对杂种一代产量表现的影响与其对后期干物质生产与分配的影响密切相关。在４种Ｎ素条件（６０、１５０、２４０和３３０ｋｇＮ·ｈｍ＾－２）下,不育胞质对杂种一代前期干物质生产与累积呈不同程度的正效应,其平均效应值为１．３７￣１．４７ｇ·ｍ＾－２·ｄ＾－１,进入生育后期,不同Ｎ处理的胞质效应表现明显不同,在Ｎ２（１５０ｋｇＮ·ｈｍ＾－２）或Ｎ３（２４０ｋｇＮ·ｈｍ＾－２）下,不育胞     

发光酶基因标记的荧光假单胞菌X16L2在小麦根圈的定殖动态

在土壤微宇宙系统内及田间土壤中,采用发不酶基因标记检测技术研究了荧光假单胞菌（Ｐｓｅｕｄｏｍｏｎａｓ ｆｌｕｏｒｅｓｃｅｎｓ,简称Ｐｆ）Ｘ１６Ｌ２在小麦根圈的定殖动态,研究结果表明：在不同灭菌灰潮土微宇宙中,Ｐｆ．Ｘ１６Ｌ２在小麦播种后３６ｄ定殖密度可达最高水平（３．２＊１０＾４ｃｆｕ．ｇ＾－１根）,然后开始下降,最后保持在一个相对稳定的较低水平（约３．２＊１０＾２ｃｆｕ．ｇ＾－１根））。在田间条     

中国大麦矮秆种质资源的基因分析——Ⅱ.矮秆基因的染色体定位

根据连锁遗传原理,利用全套染色体形态性状标记系,对２０份中国大麦矮秆种质资源的矮秆基因,进行了染色体定位。结果表明：１５份单基因矮秆中,有１份其矮秆基因与宽护颖基因Ｚ连锁,位于２（２Ｈ）染色体短臂上;１０份的矮秆基因与ｕｚ基因等位,由３（３Ｈ）长臂携带;４份的矮秆基因与钩芒基因Ｋ连锁,位于４（４Ｈ）长臂上。５份双基因矮秆中,有３份的矮秆基因分别位于２（２Ｈ）短臂和４（４Ｈ）长臂上;１份的矮秆基因各由其３（３Ｈ）和４（４Ｈ）长臂携带;其余１份的两对矮秆基因,１对与ｕｚ基因等位,由３（３Ｈ）长臂携带,另１对则与宽护颖基因ｗ连锁,位于２（２Ｈ）短臂之上。     

不同钙-醇溶解体系丝素蛋白的制备及表征研究

采用 ４种中性盐溶液 Ｃａ（ＮＯ３）２４Ｈ２Ｏ 甲醇、Ｃａ（ＮＯ３）２４Ｈ２Ｏ 乙醇、ＣａＣｌ２ 甲醇 水和 ＣａＣｌ２ 乙醇 水（摩尔比分别为 １∶２、１∶２、１∶２∶８、１∶２∶８）处理蚕丝纤维,透析后经冷冻干燥制成固体,利用ＳＤＳ ＰＡＧＥ、电镜扫描和红外光谱对制得的固体进行表征。ＳＤＳ ＰＡＧＥ结果表明：Ｃａ（ＮＯ３）２４Ｈ２Ｏ 醇体系降解丝素蛋白较 ＣａＣｌ２ 醇 水体系降解程度高;电镜扫描的结果表明 Ｃａ（ＮＯ３）２４Ｈ２Ｏ 甲醇和 ＣａＣｌ２ 乙醇 水溶解体系处理的丝素蛋白溶解比较完全,Ｃａ（ＮＯ３）２４Ｈ２Ｏ 甲醇处理的丝素蛋白冻干后为颗粒状,而 ＣａＣｌ２ 乙醇 水处理的丝素蛋白冻干后为片状。红外光谱的结果表明：４种溶液处理后的丝素蛋白构象均介于 β折叠和无规则卷曲之间,从而为丝素蛋白在药物缓释载体领域的应用提供了一定的理论依据。     

High DNA melting activity of extremophyte Eutrema salsugineum cold shock domain proteins EsCSDP1 and EsCSDP3

Plant cold shock domain proteins (CSDP) participate in maintenance of plant stress tolerance and in regulating their development. In the present paper we show that two out of three extremophyte plant Eutrema salsugineum proteins EsCSDP1-3, namely EsCSDP1 and EsCSDP3, possess high DNA-melting activity. DNA-melting activity of proteins was evaluated using molecular beacon assay in two ways: by measuring Tm parameter (the temperature at which half of the DNA beacon molecules is fully melted) and the beacon fluorescence at 4 °C. As the ratio protein/beacon was increased, a decrease in Tm was observed. Besides DNA-melting activity of full proteins, activity was measured for three isolated cold shock domains EsCSD1-3, C-terminal domain of EsCSDP1 (EsZnF1), as well as a mixture of EsCSD1 and EsZnF1. The Tm reduction efficiency of proteins formed the following sequence: EsCSDP3≈EsCSDP1>(EsCSD1+EsZnF1)>EsZnF1>EsCSDP2. Only full proteins EsCSDP3 and EsCSDP1 demonstrated DNA-melting activity at 4 °C. The presented experimental data indicate that i: interaction of EsCSDP1-3 with beacon single-stranded region is obligatory for efficient melting; ii: cold shock domain and C-terminal domain with zinc finger motifs should be present in one protein molecule to have high melting activity.     

Shock Wave Treatment Enhances Cell Proliferation and Improves Wound Healing by ATP Release-coupled Extracellular Signal-regulated Kinase (ERK) Activation

Shock wave treatment accelerates impaired wound healing in diverse clinical situations. However, the mechanisms underlying the beneficial effects of shock waves have not yet been fully revealed. Because cell proliferation is a major requirement in the wound healing cascade, we used in vitro studies and an in vivo wound healing model to study whether shock wave treatment influences proliferation by altering major extracellular factors and signaling pathways involved in cell proliferation. We identified extracellular ATP, released in an energy- and pulse number-dependent manner, as a trigger of the biological effects of shock wave treatment. Shock wave treatment induced ATP release, increased Erk1/2 and p38 MAPK activation, and enhanced proliferation in three different cell types (C3H10T1/2 murine mesenchymal progenitor cells, primary human adipose tissue-derived stem cells, and a human Jurkat T cell line) in vitro. Purinergic signaling-induced Erk1/2 activation was found to be essential for this proliferative effect, which was further confirmed by in vivo studies in a rat wound healing model where shock wave treatment induced proliferation and increased wound healing in an Erk1/2-dependent fashion. In summary, this report demonstrates that shock wave treatment triggers release of cellular ATP, which subsequently activates purinergic receptors and finally enhances proliferation in vitro and in vivo via downstream Erk1/2 signaling. In conclusion, our findings shed further light on the molecular mechanisms by which shock wave treatment exerts its beneficial effects. These findings could help to improve the clinical use of shock wave treatment for wound healing.     

Ultrastructural evidence for uptake of silicon-containing silicic acid analogs byUrtica pilulifera and incorporation into cell wall silica

Summary In natural environments the stinging nettle plant,Urtica pilulifera, bears stinging cells in which electron dense silica deposits occupy a significant volume of the cell wall. Plants were grown in hydroponic solutions with and without supplements of silicic acid, the chemical form of silicon available to biological systems to determine if this plant and the stinging cells will grow normally under conditions of silicon starvation. In separate experiments, several analogs of silicic acid were added as supplements to the hydroponic solution to determine whether silicic acid binding sites had detectably different specificities for the different molecular structures of the analogs. The analogs [(R-)_nSi(-OH)_m] have the following structures (R, n, m): (1)-H, 1, 3; (2)-CH₃, 1, 3; (3)-CH₃, 2, 2; (4)-CH₃, 3, 1; (5)-CH₂CH₃, 1, 3; and (6)-C₆H₅, 1, 3. Electron microscopy was used as an assay for the uptake and incorporation of analogs into an electron dense silica-like product in the stinging cell wall. The results indicate that cell wall silica production occurred only when the analog contained at least three hydroxyl groups. The morphology and ontogeny of the plant was normal except for: 1, the appearance of green spots on the leaves when the analog contained two or more hydroxyl groups, and 2, total blockage of flowering by the two methyl derivative of silicic acid, (CH₃)₂Si(OH)₂.     

Improving ethanol tolerance of a self-flocculating yeast by optimization of medium composition

High ethanol tolerance is a desired property of industrial yeast strains for efficient ethanol fermentation. In this study, the impact of medium composition on ethanol tolerance of the self-flocculating yeast SPSC01 was investigated using a chemically defined medium. Single-factor experiments revealed that besides magnesium and calcium, zinc also exhibited significant protective effect against ethanol toxicity; addition of 0.02 g/l zinc sulfate significantly increased cell viability in the ethanol shock treatment. Metal ions of manganese, cobalt, and ferrous failed to promote ethanol tolerance, although addition of 0.02 g/l cobalt increased ethanol production without apparent influence on ethanol tolerance. Furthermore, Uniform Design method was employed to obtain the medium with high cell viability, and the key nutrient factors in the medium composition were revealed to be (NH₄)₂SO₄, K₂HPO₄, vitamin mixtures, and the metal ions of magnesium, calcium and zinc. The optimized combination of metal ions addition was (g/l): MgSO₄ 0.4, CaCl₂ 0.2, ZnSO₄ 0.01. The highest cell viability (90.2%) of SPSC01 against ethanol shock treatment was observed in the optimized medium, which demonstrated significant improvement of ethanol tolerance of the self-flocculating yeast.     

Plant complex type free N-glycans occur in tomato xylem sap

Free N-glycans (FNGs) are ubiquitous in growing plants. Further, acidic peptide:N-glycanase is believed to be involved in the production of plant complex-type FNGs (PCT-FNGs) during the degradation of dysfunctional glycoproteins. However, the distribution of PCT-FNGs in growing plants has not been analyzed. Here, we report the occurrence of PCT-FNGs in the xylem sap of the stem of the tomato plant.

Abbreviations: RP-HPLC: reversed-phase HPLC; SF-HPLC: size-fractionation HPLC; PA-: pyridylamino; PCT: plant complex type; Hex: hexose; HexNAc: N-acetylhexosamine; Pen: pentose; Deoxyhex: deoxyhexose; Man: D-mannose; GlcNAc: N-acetyl-D-glucosamine; Xyl: D-xylose; Fuc: L-fucose; Le^a: Lewis a (Galβ1-3(Fucα1-4)GlcNAc); PCT: plant complex type; M3FX: Manα1-6(Manα1-3)(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc-PA; GN2M3FX: GlcNAcβ1-2Manα1-6(GlcNAcβ1-2Manα1-3)(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc-PA; (Le^a)1GN1M3FX: Galβ1-3(Fucα1-4)GlcNAc1-2 Manα1-6(GlcNAcβ1-2Manα1-3)(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc-PA or GlcNAc1-2Manα1-6(Galβ1-3(Fucα1-4)GlcNAc1-2Manα1-3)(Xylβ1-2)Manβ1-4GlcNAcβ1-4(Fucα1-3)GlcNAc-PA.     

Protein Synthesis in Maize during Anaerobic and Heat Stress

Protein accumulation and protein synthesis were investigated during anaerobic stress and heat shock in maize seedlings (Zea mays L.). Antibodies against alcohol dehydrogenase (ADH) and cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPC) were used to investigate the expression of the genes encoding these proteins during stress treatment. ADH1 protein accumulation is shown to increase about 10-fold in the root after 24 hours of anaerobic treatment. The Gpc gene products are separable into two size classes: the slow mobility GAPC1 and GAPC2 (GAPC1/2), and the faster GAPC3 and GAPC4 (GAPC3/4). The GAPC1/2 antigen did not increase at all, whereas the GAPC3/4 antigen increased less than fourfold. The proteins synthesized in the root during aerobic and anaerobic conditions were compared, and GAPC3/4 was identified as an anaerobic polypeptide. In vitro translations were used to estimate the levels of different mRNAs in roots following anaerobiosis, recovery from anaerobiosis, and heat shock. This was compared with the in vivo protein synthesis rates in roots labeled under identical conditions. In vivo labeling indicates that GAPC and ADH are not heat shock proteins. Although both GAPC3/4- and ADH1-translatable mRNA levels increase about 10-fold during anaerobiosis, in vivo labeling of these proteins (relative to total protein synthesis) is further enhanced, leading to a selective translation effect for ADH1 of threefold, and for GAPC3/4 of sixfold. In contrast, anoxia causes no change in GAPC1/2-translatable mRNA levels or in vivo labeling. As an additional comparison, β-glucosidase mRNA levels are found to be constant during anoxia, but in vivo synthesis decreases.     

HSP70-3 Interacts with Phospholipase Dδ and Participates in Heat Stress Defense

Heat shock proteins (HSPs) function as molecular chaperones and are key components responsible for protein folding, assembly, translocation, and degradation under stress conditions. However, little is known about how HSPs stabilize proteins and membranes in response to different hormonal or environmental cues in plants. Here, we combined molecular, biochemical, and genetic approaches to elucidate the involvement of cytosolic HSP70-3 in plant stress responses and the interplay between HSP70-3 and plasma membrane (PM)-localized phospholipase Dδ (PLDδ) in Arabidopsis (Arabidopsis thaliana). Analysis using pull-down, coimmunoprecipitation, and bimolecular fluorescence complementation revealed that HSP70-3 specifically interacted with PLDδ. HSP70-3 bound to microtubules, such that it stabilized cortical microtubules upon heat stress. We also showed that heat shock induced recruitment of HSP70-3 to the PM, where HSP70-3 inhibited PLDδ activity to mediate microtubule reorganization, phospholipid metabolism, and plant thermotolerance, and this process depended on the HSP70-3–PLDδ interaction. Our results suggest a model whereby the interplay between HSP70-3 and PLDδ facilitates the re-establishment of cellular homeostasis during plant responses to external stresses and reveal a regulatory mechanism in regulating membrane lipid metabolism.

The heat shock protein 70-3 interacts with phospholipase Dδ to regulate microtubule organization, lipid metabolism, and plant thermotolerance in Arabidopsis.     

Changes in Circulating Procalcitonin Versus C-Reactive Protein in Predicting Evolution of Infectious Disease in Febrile,Critically Ill Patients

Objective

Although absolute values for C-reactive protein (CRP) and procalcitonin (PCT) are well known to predict sepsis in the critically ill, it remains unclear how changes in CRP and PCT compare in predicting evolution of: infectious disease, invasiveness and severity (e.g. development of septic shock, organ failure and non-survival) in response to treatment. The current study attempts to clarify these aspects.

Methods

In 72 critically ill patients with new onset fever, CRP and PCT were measured on Day 0, 1, 2 and 7 after inclusion, and clinical courses were documented over a week with follow up to Day 28. Infection was microbiologically defined, while septic shock was defined as infection plus shock. The sequential organ failure assessment (SOFA) score was assessed.

Results

From peak at Day 0–2 to Day 7, CRP decreased when (bloodstream) infection and septic shock (Day 0–2) resolved and increased when complications such as a new (bloodstream) infection or septic shock (Day 3–7) supervened. PCT decreased when septic shock resolved and increased when a new bloodstream infection or septic shock supervened. Increased or unchanged SOFA scores were best predicted by PCT increases and Day 7 PCT, in turn, was predictive for 28-day outcome.

Conclusion

The data, obtained during ICU-acquired fever and infections, suggest that CRP may be favoured over PCT courses in judging response to antibiotic treatment. PCT, however, may better indicate the risk of complications, such as bloodstream infection, septic shock, organ failure and mortality, and therefore might help deciding on safe discontinuation of antibiotics. The analysis may thus help interpreting current literature and design future studies on guiding antibiotic therapy in the ICU.