中国农业科学院等6家单位发现植物株型发育新机制

正7月13日,《Nature Plants》在线发表了中国农业科学院蔬菜花卉研究所、深圳农业基因组研究所、中科院生物物理所、加州大学戴维斯分校等6家单位合作研究的关于作物株型发育基因表达调控的最新研究成果。研究发现黄瓜卷须发育的身份基因TCP家族的转录因子—TEN调控黄瓜卷须发育和运动的分子机制,揭示了基因内部结合的转录因子如何调控基因表达,为深入认识株型发育的基因调控网络提供了重要的突破。     

蔬菜作物盐胁迫响应及耐盐机制研究进展

近年来,由于不合理的灌溉及其他环境因素,土壤盐渍化问题日趋严重,盐胁迫严重影响蔬菜作物生长、发育和产量,限制土地利用。盐胁迫主要改变蔬菜作物的净光合生产率、呼吸作用、细胞膜结构和各类酶活性。本文综述了盐胁迫对蔬菜作物表观形态的改变和植物内部生理生化指标的影响,阐述了蔬菜对盐胁迫的生理响应（包括渗透调节、离子区域化、抗氧化代谢）和分子调控（包括转录因子、离子平衡调控基因、抗氧化基因、小RNA）机制;总结了各类蔬菜耐盐性的鉴定方法;展望了蔬菜作物耐盐性的研究方向。     

《中国蔬菜》2013·6 学术论文导读

植物果实发育调控的分子机理研究进展蒋励等(中国农业大学农学与生物技术学院,北京100193)-《中国蔬菜》2013(6) 果实的发育与成熟是一个复杂的过程,果实大小、形状、颜色、品质、风味等都随着果实发育和成熟而变化,并受一系列果实发育相关基因的影响和调控.研究植物果实发育调控的分子机理对于今后提高果实品质具有重要的意义.因此,本文主要综述了拟南芥和番茄中果实发育与成熟相关基因的发掘与相互作用,以及果实发育调控的分子机理研究进展,为今后的果实发育研究和育种工作的开展提供一定的理论指导.     

瓜类种子性状遗传及分子生物学研究进展

种子性状与植物的生长发育、产品器官的产量和品质以及环境适应性等密切相关。探究种子
性状遗传和发育调控机制对作物种质改良、提高产量与解决生物能源问题具有重要作用。近年来,种子性
状研究在瓜类蔬菜作物上取得较快进展,本文综述了瓜类种子性状的遗传特性、发育调控机制及分子生物
学方面的研究进展,并对目前该领域相关研究中存在的问题进行了讨论,对未来的研究方向提出了展望。     

《中国蔬菜》2013·14 学术论文导读

瓜类种子性状遗传及分子生物学研究进展王敏等(中国农业科学院蔬菜花卉研究所,北京100081)—《中国蔬菜》2013(14)种子性状与植物的生长发育、产品器官的产量和品质以及环境适应性等密切相关。探究种子性状遗传和发育调控机制对作物种质改良、提高产量与解决生物能源问题具有重要作用。近年来,种子性状研究在瓜类蔬菜作物上取得较快进展,本文综述了瓜类种子性状的遗传特性、发育调控机制及分子     

蔬菜作物中类胡萝卜素研究进展

类胡萝卜素是一种重要的天然色素,广泛存在于动植物以及微生物体内,是人体维生素A的主要来源,对人类健康具有重要作用.在蔬菜作物中,不同种类和含量的类胡萝卜素赋予其颜色的多样性.植物类胡萝卜素积累是一个复杂的过程.它与有色体发育有关,由多个结构基因和转录因子调控,还受环境因素影响.本文对蔬菜作物中类胡萝卜素的合成代谢途径及...     

LED光质调控蔬菜作物几类生物活性物质合成代谢的研究进展

蔬菜作物中富含多种具有调节人体新陈代谢、提高免疫力、预防慢性疾病以及防癌抗癌等生物学功能的活性物质。光照是影响蔬菜作物生长发育的重要环境因子之一,同时也是参与调控植物体内各种生物活性物质合成与代谢的重要因子。综述了LED光质及比例对蔬菜作物体内酚类化合物、类胡萝卜素、萝卜硫苷、维生素C等活性物质合成代谢的影响,并简要概括了光质调控上述活性物质的分子机制。该综述不仅可为蔬菜作物生物活性物质的光质调控提供理论参考,也可为LED光质调控高品质蔬菜作物的生产提供理论支撑和技术支持。     

植物花粉发育相关基因的研究进展

植物花粉发育是一个复杂的生理生化过程,涉及众多基因的表达调控,现已在多种作物中鉴定了大量与花粉发育相关的基因。这些基因中的某个基因结构或表达发生变异,都会引起花药发育异常,从而导致花粉败育。本文综述了植物花粉发育相关基因的研究进展,讨论了花粉发育的过程及其相关基因的表达,为以后植物花粉发育过程的研究提供理论参考。     

光质对蔬菜作物类胡萝卜素合成与调控研究进展

本文综述了不同光质对蔬菜作物类胡萝卜素含量的调控作用，重点从生物合成关键基因调控、翻译后调控及库源调控方面总结了光质对蔬菜作物类胡萝卜素的调控机制，旨在为蔬菜作物高效种植、产品器官品质光质调控及植物照明灯具开发提供理论参考。     

蔬菜种业经理必备的蔬菜专业基础知识(上)

随着社会的发展和人民生活水平的提高,人们对蔬菜产量和产品质量的要求也日益增长.提高蔬菜的产量和产品质量通常可从两方面人手:一是选育优良新品种和高质量种子;二是通过改善栽培管理条件、调控植物的生长和发育,使作物的遗传潜力得以充分表达.其中优良品种的选育和良种应用仍然是主要的途径.本文将对蔬菜的引种、新品种选育和良种繁育的相关知识作一些介绍.     

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.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

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.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [³-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10^-6-10^-4 mmol/L) stimulated [³-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [³-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10^-6-10^-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl₂ for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.