光影响植物花青苷合成研究

近几年来,对于环境因子影响花青苷合成的研究已有相关报道。现基于对花青苷合成影响最大的光因子,结合国内外研究,综述了光照时间、光照强度和不同光质对植物花青苷合成途径中相关酶活性的调节作用、相关基因的调控作用以及植物的呈色反应的影响,指出对于大多数植物而言,光照时间越长,越有利于花青苷的合成,植物呈色效果明显;光照促进植物花青苷合成和积累,光强越大,提高花青苷合成途径中相关酶活性,促进相关基因上调表达以及促进植物花青苷的积累,呈色效果明显;在不同的光质中,对合成花青苷最有效的是蓝光和紫外光,可以提高酶活性,增强相关基因的表达,促进植物呈色。此外,还分析了目前花青苷光环境研究存在的问题,为今后研究提供新思路和新方向。     

花青苷生物合成转录调控研究进展

 花青苷生物合成由一系列结构基因编码的酶催化完成,而结构基因的表达受MYB、bHLH 和WD40 这3 类转录因子组成的MBW（MYB-bHLH-WD40）转录复合体的协同调控。花青苷合成的转 录调控研究最先在30 多年前见于玉米、拟南芥和矮牵牛等模式植物,近年来在肉质果实上也取得了重要 进展。在介绍果实花青苷的种类、分布与功能的基础上,回顾了MYB、bHLH、WD40 这3 类转录因子 的基本特性及其在花青苷合成调控中的作用,进而就MBW 转录复合体协同调控果实花青苷生物合成的 机制研究的近年进展进行了综述。     

花青苷生物合成转录调控研究进展

花青苷生物合成由一系列结构基因编码的酶催化完成,而结构基因的表达受 MYB、bHLH和 WD40 这 3 类转录因子组成的 MBW（MYB-bHLH-WD40）转录复合体的协同调控。花青苷合成的转录调控研究最先在 30 多年前见于玉米、拟南芥和矮牵牛等模式植物,近年来在肉质果实上也取得了重要进展。在介绍果实花青苷的种类、分布与功能的基础上,回顾了 MYB、bHLH、WD40 这 3 类转录因子的基本特性及其在花青苷合成调控中的作用,进而就 MBW 转录复合体协同调控果实花青苷生物合成的机制研究的近年进展进行了综述。     

红皮梨着色与花青苷合成研究进展

红皮梨资源非常丰富,包括砂梨、秋子梨、新疆梨、白梨和西洋梨在内的世界梨主栽种类,具有很高的商业价值。综述了红皮梨果实着色与其花青苷合成研究所取得的进展。重点介绍了红皮梨着色过程中色素种类及其变化、花青苷的组分、花青苷在果皮组织中的分布、花青苷的合成途径以及相关酶活性的变化,同时还介绍了与花青苷合成有关的结构基因、调节基因和转录因子等研究进展,并从内因和外因两方面阐述了花青苷代谢与红皮梨着色的关系,为今后研发红皮梨优质高效栽培技术、培育色泽鲜艳的红皮梨新品种奠定理论基础。     

蔬菜花青苷生物合成及转录调控的研究进展

蔬菜在人们日常饮食中占据重要地位,可为人体提供维生素、矿物质等多种营养物质。颜色是蔬菜育种中重要的感官指标,而蔬菜颜色的形成受不同类型花青苷的影响。花青苷在植物生长发育、延缓机体衰老、预防心脏病等方面都发挥重要作用。研究表明,花青苷的生物合成受结构基因和调节基因的共同调控,分子水平上对蔬菜花青苷遗传机制的研究也在不断加深。笔者综述了与蔬菜花青苷生物合成途径中相关结构基因及其转录调控基因的研究现状,并对蔬菜花青苷的研究前景进行了展望。     

套袋对苹果果皮花青苷合成及着色的影响

套袋是提高苹果果实着色的主要技术措施之一,也是研究苹果果皮花青苷合成和基因表达的重要手段。苹果果皮花青苷的合成经由苯丙烷类代谢途径,编码苹果花青苷合成酶类的基因已得到克隆。套袋后果皮花青苷合成酶类的基因表达受到抑制,因而抑制了花青苷合成;摘袋后果皮花青苷迅速合成,与套袋后果皮光受体浓度增加和叶绿素含量降低从而提高对光的敏感度、迅速启动花青苷合成酶类的基因协同表达有关。果皮色素特别是花青苷和叶绿素的含量、比例和分布决定果实的着色状况,套袋促进果皮花青苷合成的同时大大降低了叶绿素含量,从而使果实着色鲜艳。     

百合花色机理研究进展

百合花色主要由花青苷和类胡萝卜素形成,一般粉色和棕色花中主要成分是花青苷;黄色和橙色花中主要成分是类胡萝卜素;红色是由花青苷和类胡萝卜素共同组成。百合花色的遗传现象比较复杂。目前初步构建了几个群体,通过遗传连锁图谱标记了花色相关位点。百合中花青苷和类胡萝卜素合成代谢途径中的大部分结构基因已经被克隆和研究。花青苷合成途径中的转录因子LhMYB12调控百合花被片中的花青苷的有无,其转录水平调控花青苷的颜色强度和着色类型。本文总结了百合花朵的着色机理研究,为进一步开展百合花色育种提供了理论参考。     

花色素苷生物合成与分子调控研究进展

花色素苷是决定植物花色的主要色素,其生物合成是目前研究得最为清楚的植物次生代谢途径之一。花色素苷的生物合成主要由于F3H,F3'H和F3'5'H三个关键酶的作用形成3个分支,最终分别生成橙色到砖红色的天竺葵素糖苷,红色的矢车菊素糖苷和蓝色到紫色的飞燕草素糖苷,因此, F3'H,F3'5'H和DFR基因是利用遗传转化引入花卉植物原本缺乏的花色代谢途径的关键基因。花色素苷合成结构基因的转录调控是目前研究的热点,对结构基因的转录进行调控的转录因子主要包括两大类相互作用的因子－bHLH和MYB类转录因子,花色素苷合成的转录调控机理的基本模式,包括bHLH和MYB类因子之间的相互作用,以及它们对结构基因顺式元件的识别和结合已经阐述的比较清楚。另外,对于一些处于bHLH和MYB上游的, WD40类因子和光敏色素的研究开启了从信号传导到花色素苷合成的整个调控过程的研究。     

科技文摘

正UV-A诱导大豆芽苗菜下胚轴中花青苷积累的分子机理目的:研究长波紫外光(UV-A)、白光(W)和蓝光(B)对大豆芽苗菜下胚轴中花青苷含量、花青苷合成相关酶活性、花青苷合成途径相关基因及光受体基因表达量的影响,以探明UV-A诱导大豆芽苗菜下胚轴中花青苷生物合成的分子机理,为光质调控技术应用于大豆芽苗菜工业化生产提供理论依据。方法:以大豆‘东农690’为试材,以黑暗培养为对照,连续     

茄子紫色形成的分子研究进展

对茄子花青苷的种类和功能、影响茄子各组织紫色形成和花青苷积累的关联位点、以及茄子花青苷合成的结构基因和调控基因进行总结,为解析茄子紫色形成的分子机制提供参考。     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Expression and significance of c-IAP2 and GAS1 in Hodgkin's lymphoma and anaplastic large cell lymphoma

AIM: To detect the expression of cytoplasmic inhibitor of apoptosis protein 2 (c-IAP2) and growth arrest-specific gene 1 (GAS1) in Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL) and to investigate the role of two genes in the pathogenesis of HL and ALCL.METHODS: HE staining, the antibodies CD30, CD15, CD45RO and CD20 were used to screen the cases of HL and ALCL from 288 cases of lymphoma. The clarified HL and ALCL were subjected for immunohistochemical staining by SP and ABC methods to analyze the expression of c-IAP2 and GAS1. RESULTS: ①The positive rate of c-IAP2 in HL was 25/26(96.1%) while that in ALCL was 6/19(31.6%), there presented statistic significance between HL and ALCL groups(P<0.05), meanwhile the positive rate of GAS1 showed statistic significance between HL and ALCL groups(P<0.05). ②Two cases were showed to be a mixed type combined with large tumor cells of HL and relatively smaller tumor cells of ALCL.CONCLUSION: ①The different expression of c-IAP2 and GAS1 in HL and ALCL implied a different mechanism of oncogenesis and the different defects in the pathway of signal transduction of apoptosis in HL and ALCL;②Few cases showed an overlap and a likely transitional state between HL and ALCL; ③The different expressing manner of GAS1 and c-IAP2 in HL and ALCL implied the potential marks for the differential dignosis of two kinds of lymphoma.     

Ergebnisse der Leistungsprüfungen der Süßkirschensorte ‚Stella‘ auf Gisela- und Weiroot-Unterlagen in Bulgarien

Zusammenfassung Die Leistungsprüfungen wurden im Zeitraum 1997 bis 2003 mit den Unterlagen Gisela 4 und 5, den Klonnummern 195/20 und 497/8 aus der Gisela-Serie sowie Weiroot 10, 13, 53, 72 und 158 durchgeführt. Dabei dienten Sämlinge von P1 (bulgarische Selektion aus Prunus mahaleb) als Kontrolle. Alle Unterlagen waren mit der Sorte Stella veredelt und im Dezember 1996 in der Versuchsanlage der Agraruniversität in Plovdiv, Bulgarien, im Abstand von 6 m×4,5 m gepflanzt worden. Dabei erfolgte ein Pflanzschnitt. Nach Abschluss der natürlichen Kronenentwicklung wurde jedes Jahr ein Winterschnitt vorgenommen. Der Boden wurde durch mechanische Bearbeitung offen gehalten und nach dem 4. Standjahr wurden die Baumstreifen mit Herbiziden behandelt. Die Wasserversorgung erfolgte durch eine dem natürlichen Gefälle folgende Überflutung, allerdings nicht immer zum optimalen Zeitpunkt, da keine eigene Wasserquelle zur Verfügung stand.Basierend auf den Ergebnissen bis zum Anfang des 7. Standjahres können die untersuchten Unterlagen in zwei Gruppen differenziert werden: starkwüchsig—Weiroot 10, P1 und Weiroot 13; mittelstarkwachsend bis schwachwüchsig—Gi 497/8, Gisela 4, Weiroot 53, Weiroot 158, Gi 195/20, Weiroot 72 und Gisela 5. Letztere zeichnete sich durch besondere Schwachwüchsigkeit aus. Die meisten Wurzelschosser bildeten Gisela 4, Weiroot 10 und Weiroot 13. Weiroot 53, Weiroot 72 und Weiroot 158 entwickelten deutlich weniger und P1, Gisela 5, Gi 195/20 sowie Gi 497/8 keine Wurzelschosser. Den frühesten Blühbeginn induzierte Gisela 4. Die anderen Unterlagen führten, in Abhängigkeit von den Temperaturbedingungen des jeweiligen Jahres, zu einer Verspätung der Blüte: P1 und Weiroot 10 um 1–2 Tage; Gi 497/8, Weiroot 13 und Weiroot 158 um 2–4 Tage; Weiroot 72 um 2–7 Tage; Gi 195/20 um 3–6 Tage; Weiroot 53 um 3–8 Tage und Gisela 5 um 3–10 Tage. Die Reifezeit der Früchte war bei den Bäumen auf Gisela 5 im Vergleich zu den anderen Varianten um 2–3 Tage verspätet. Gisela 5, Weiroot 72 und Gisela 4 induzierten bei der aufveredelten Sorte die höchsten Ertragsleistungen, P1 die geringsten. Bei den Bäumen auf Gisela 5 war die Fruchtgröße geringer als bei den anderen Unterlagen. Bäume auf Gisela 5 brauchen intensive Pflege. Nur wenn alle Produktionsfaktoren und kulturtechnischen Maßnahmen optimiert werden, kann das hohe Ertragspotenzial dieser Unterlage ausgeschöpft werden.     

Effects of patch attributes, barriers, and distance between patches on the distribution of a rock-dwelling rodent (Lagidium viscacia)

We tested whether size of habitat patches and distance between patches are sufficient to predict the distribution of the mountain vizcacha Lagidium viscacia a large, rock-dwelling rodent of the Patagonian steppe Argentina, or whether information on other patch and landscape characteristics also is required. A logistic regression model including the distance between rock crevices and depth of crevices, distance between a patch and the nearest occupied patch, and whether or not there was a river separating it from the nearest occupied patch was a better predictor of patch occupancy by mountain vizcachas than was a model based only on patch size and distance between patches. Our results indicate that a simple metapopulation analysis based on size of habitat patches and distance between patches may not provide an accurate representation of regional population dynamics if patches vary in habitat quality independently of patch size and features in the matrix alter connectivity. This revised version was published online in August 2006 with corrections to the Cover Date.