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1.
Pan J  Cui K  Wei D  Huang J  Xiang J  Nie L 《Physiologia plantarum》2011,141(4):321-331
Stem non-structural carbohydrates (NSCs) and its relationship with yield formation was investigated under low nitrogen (LN) and normal nitrogen (NN) treatments, using 46 recombinant inbred lines from Zhenshan 97 × Minghui 63 (Oryza sativa). Apparent contribution of transferred NSC to grain yield (AC(NSC) ) ranged from approximately 1 to 28% under LN and from 1 to 15% under NN. Concentration and total mass of NSC in stem (TM(NSC) ) at heading, apparent transferred mass of NSC (ATM(NSC) ) and AC(NSC) were larger under LN compared with NN. However, there was no significant difference in the apparent ratio of transferred NSC from stems to grain (AR(NSC) ). ATM(NSC) was positively correlated with grain yield, 1000-grain weight and AC(NSC) under both nitrogen levels, whereas AR(NSC) was highly correlated with harvest index and AC(NSC) . Leaf area contributed more strongly to grain yield compared with ATM(NSC) under both LN and NN. ATM(NSC) showed larger direct effects on grain yield under LN compared with NN. TM(NSC) at heading, small vascular bundles (SVBs) and spikelets per m(2) under LN had positive direct effects on ATM(NSC) . SVB and spikelets per m(2) under LN had larger and positive direct effects, and large vascular bundles had negative direct effects on AR(NSC) . TM(NSC) at heading and SVB under LN had positive direct effects on AC(NSC) . In brief, LN supply increased stem NSC accumulation and translocation to developing grain. Components of the source-sink-flow system showed different effects on NSC translocation and contribution to yield formation, depending on genotype and nitrogen level.  相似文献   

2.
The in vivo anti-influenza virus and antivaccinia virus activity of 156 biologically active compounds was determined. One of two criteria was used for evaluating activity against the influenza virus. The criteria were increase in survivor number and mean survival time, and reduction in virus-induced lung consolidation in treated, infected Swiss mice. Increase in survivor number and mean survival time were the criteria for evaluation of antivaccinia virus activity. Several drug doses were tested against two virus concentrations to demonstrate antiviral activity more clearly. Two compounds were considered significantly active against the influenza virus: DL-noformicin (NSC 72942) and amantadine hydrochloride (NSC 83653). Eleven compounds had reproducible activity against vaccinia virus: isatin-beta-thiosemicarbazone (NSC 721), 6-azauracil (NSC 3425), 9-alpha-fluoro-2alpha-methylhydrocortisone 21-acetate (NSC 12601), 5-[bis(2-chloroethyl)amino]uracil (NSC 34462), 5-iodo-2'-deoxyuridine (NSC 39661), streptonigrin (NSC 45383), N-methylisatin beta-thiosemicarbazone (NSC 69811), cytovirin (NSC 91770), 9-beta-D-arabinofuranosyladenine (NSC 404241), and 5-(mercaptomethyl)uracil (NSC 529351).  相似文献   

3.
ABCC1 is a member of the ATP-binding Cassette super family of transporters, actively effluxes xenobiotics from cells. Clinically, ABCC1 expression is linked to cancer multidrug resistance. Substrate efflux is energised by ATP binding and hydrolysis at the nucleotide-binding domains (NBDs) and inhibition of these events may help combat drug resistance. The aim of this study is to identify potential inhibitors of ABCC1 through virtual screening of National Cancer Institute (NCI) compounds. A threedimensional model of ABCC1 NBD2 was generated using MODELLER whilst the X-ray crystal structure of ABCC1 NBD1 was retrieved from the Protein Data Bank. A pharmacophore hypothesis was generated based on flavonoids known to bind at the NBDs using PHASE, and used to screen the NCI database. GLIDE was employed in molecular docking studies for all hit compounds identified by pharmacophore screening. The best potential inhibitors were identified as compounds possessing predicted binding affinities greater than ATP. Approximately 5% (13/265) of the hit compounds possessed lower docking scores than ATP in ABCC1 NBD1 (NSC93033, NSC662377, NSC319661, NSC333748, NSC683893, NSC226639, NSC94231, NSC55979, NSC169121, NSC166574, NSC73380, NSC127738, NSC115534), whereas approximately 7% (7/104) of docked NCI compounds were predicted to possess lower docking scores than ATP in ABCC1 NBD2 (NSC91789, NSC529483, NSC211168, NSC318214, NSC116519, NSC372332, NSC526974). Analyses of docking orientations revealed P-loop residues of each NBD and the aromatic amino acids Trp653 (NBD1) and Tyr1302 (NBD2) were key in interacting with high-affinity compounds. On the basis of docked orientation and docking score the compounds identified may be potential inhibitors of ABCC1 and require further pharmacological analysis.

Abbreviations

ABC - ATP-binding cassette, DHS - dehydrosilybin, MDR - multidrug resistance, NBD - nucleotide-binding domain, PDB - protein data bank.  相似文献   

4.
Non‐structural carbohydrates (NSC) are crucial for forest resilience, but little is known regarding the role of bark in NSC storage. However, bark's abundance in woody stems and its large living fraction make it potentially key for NSC storage. We quantified total NSC, soluble sugar (SS) and starch concentrations in the most living region of bark (inner bark, IB), and sapwood of twigs, trunks and roots of 45 woody species from three contrasting tropical climates spanning global extremes of bark diversity and wide phylogenetic diversity. NSC concentrations were similar (total NSC, starch) or higher (SS) in IB than wood, with concentrations co‐varying strongly. NSC concentrations varied widely across organs and species within communities and were not significantly affected by climate, leaf habit or the presence of photosynthetic bark. Starch concentration tended to increase with density, but only in wood. IB contributed substantially to NSC storage, accounting for 17–36% of total NSC, 23–47% of SS and 15–33% of starch pools. Further examination of the drivers of variation in IB NSC concentration, and taking into account the substantial contribution of IB to NSC pools, will be crucial to understand the role of storage in plant environmental adaptation.  相似文献   

5.
We searched the National Cancer Institute (NCI) compound library for structures related to the antitumor quinoline NSC3852 (5-nitroso-8-quinolinol) and used a computer algorithm to predict the antiprotozoan activity for each of 13 structures. Half of these compounds inhibited Toxoplasma gondii tachyzoite propagation in human fibroblasts at 相似文献   

6.
Neural stem/progenitor cells (NSC) have the potential for treatment of a wide range of neurological diseases such as Parkinson Disease and multiple sclerosis. Currently, NSC have been isolated only from hippocampus and subventricular zone (SVZ) of the adult brain. It is not known whether NSC can be found in all parts of the developing mid-trimester central nervous system (CNS) when the brain undergoes massive transformation and growth. Multipotent NSC from the mid-trimester cerebra, thalamus, SVZ, hippocampus, thalamus, cerebellum, brain stem and spinal cord can be derived and propagated as clonal neurospheres with increasing frequencies with increasing gestations. These NSC can undergo multi-lineage differentiation both in vitro and in vivo, and engraft in a developmental murine model. Regionally-derived NSC are phenotypically distinct, with hippocampal NSC having a significantly higher neurogenic potential (53.6%) over other sources (range of 0%–27.5%, p<0.004). Whole genome expression analysis showed differential gene expression between these regionally-derived NSC, which involved the Notch, epidermal growth factor as well as interleukin pathways. We have shown the presence of phenotypically-distinct regionally-derived NSC from the mid-trimester CNS, which may reflect the ontological differences occurring within the CNS. Aside from informing on the role of such cells during fetal growth, they may be useful for different cellular therapy applications.  相似文献   

7.
8.
Non-structural carbohydrates (NSC) play important roles in metabolic processes of plants and represent important functional traits in plant adaptation to the external environment. However, there are few reports concerning intra-annual NSC distribution in temperate deciduous forests, especially for the purpose of comparison among different stand ages on China’s Loess Plateau. Here, NSC allocation dynamics with age ring-porous black locust tree was determined for the growing (May) and dormant (November) seasons over the period from sapling to dying trees—defined as a completely defoliated tree with dried branches in the growing season. It was noted that regardless of tree age, NSC concentration was highest in coarse roots [16.4 g per 100 g of dry mass (16.4% DM)] and stems (15.1% DM). At the tree level, NSC concentration was highest (14.3% DM) in a 30-year-old stand in November and lowest (4.1% DM) in dying stands in May. The pool of NSC at tree level was highest (25.2 kg DM per tree) in 30-year-old stands in November and lowest (0.13 kg DM per tree) in sapling stands in May. The concentration of NSC was significantly lower in May than in November for all tree ages, organs, and biochemical components. The results underscored the importance of NSC in plant growth on China’s Loess Plateau. It also provided a useful insight into the dynamics of NSC from sapling to dying broadleaved tree species.  相似文献   

9.
非结构性碳水化合物(NSC)在植物体内的含量及分配对植物生长和存活至关重要。开展氮沉降和降雨变化对幼苗NSC影响的研究,为揭示干旱导致幼苗死亡机理及预测气候变化背景下幼苗自然更新及培育提供依据。本研究以1年生红砂幼苗为对象,测定了不同降雨(降雨减少(W-)、自然降水(W)和降雨增多(W+))和氮添加(N0(0 g N·m-2·a-1)、N1(4.6 g N·m-2·a-1)、N2(9.2 g N·m-2·a-1)、N3(13.8 g N·m-2·a-1))条件下红砂幼苗各器官NSC及其组分含量。结果表明:红砂幼苗各器官NSC含量为28.8~71.8mg·g-1,叶片含量最高,茎含量最低。氮添加和降雨变化对红砂幼苗叶片和根系淀粉及总NSC含量有显著影响,而对茎无显著影响。各降雨条件下,氮添加均促进了红砂幼苗叶片淀粉和总NSC累积,在降雨增加30%的条件下氮的促进效应更显著,中高氮(N2和N3)叶片淀粉与总NSC含量显著高于低氮水平(N1和N0);在低氮降雨减少30%(N1W-)处理下,红砂叶片淀粉和NSC含量最小,而根系淀粉和NSC含量最大,即低氮干旱胁迫下红砂可通过NSC在不同器官的重...  相似文献   

10.
枝条是碳供应器官和碳需求器官的连接者, 研究其非结构性碳水化合物(NSC)含量的季节变化对理解树木体内的碳分配至关重要。该研究以秦岭东段栓皮栎(Quercus variabilis)优势群落为研究对象, 于2016年5月至2017年5月, 在其分布的海拔上下限(650 m和970 m), 通过在展叶期采用旬尺度和在非展叶期采用月尺度相结合的周期性取样方法(共计12次), 测定栓皮栎枝条NSC组分及含量, 并观测同期叶片物候变化。结果表明: (1)栓皮栎枝条NSC含量随季节波动较小, 变化差异不显著。但枝条可溶性糖含量(高海拔)或淀粉含量(低海拔)在一定生境条件下, 均存在明显的季节波动, 说明栓皮栎枝条可溶性糖和淀粉之间存在动态转化过程。(2)栓皮栎枝条NSC组成以可溶性糖为主(61%), 这可能是该树种在暖温带季风气候区所采取的生长策略。(3)土壤含水量(正相关)和饱和水汽压差(负相关)分别是在高海拔和低海拔影响栓皮栎枝条NSC含量的主导环境因子, 说明相比高海拔, 低海拔的栓皮栎可能对高温引起的水分胁迫更敏感。(4)结合叶片物候发现, 栓皮栎枝条NSC含量最大值出现在萌芽前(3月中下旬, 11%左右), 最小值出现在展叶后期(4月末, 5%左右), 叶片萌芽展叶后枝条NSC含量下降。总体而言, 枝条NSC含量在高低海拔不存在显著差异, 但春季萌芽前后存在显著差异, 海拔引起的叶片物候时间差极可能是造成这一现象的主要原因。研究结果说明, 栓皮栎叶片物候会直接影响枝条NSC含量的季节变化, 枝条NSC含量对叶片萌芽生长至关重要, 研究结果有助于加深对栓皮栎树体内碳调配机制的理解。  相似文献   

11.
In the sturgeon fry nucleus preopticus (Npo), light and weakly differentiated neurosecretory cells (NSC) as well as differentiated (i-cells) were revealed. Among these types of cells, there were the transitional forms. No "picnomorphic" cells were found in any Npo zone. NSC contained different amounts of elementary secretory granules 110-270 nm in diameter. The distribution of organelles was evaluated statistically, their number increasing from i-cells to the NSC. These data suggest that growth and differentiation of the NSC take place during this stage of ontogeny. The results are discussed in terms of specific functioning and maturity of the NSC.  相似文献   

12.
We analysed concentrations of starch, sucrose, glucose and fructose in upper branch wood, foliage and trunk sapwood of Douglas-fir trees in height classes ranging from ~2 to ~57 m. Mean concentrations of non-structural carbohydrates (NSC) for all tissues were highest in the tallest height class and lowest in the lowest height class, and height-related trends in NSC were most pronounced in branches. Throughout a 17-month sampling period, mean values of branch NSC from the 57 m trees ranged between 30 and 377% greater than the 2 m trees. Branch NSC was inversely correlated with midday shoot water potential (Ψ(l)), shoot osmotic potential at full turgor (Ψ) and shoot extension. Temporal fluctuation in branch NSC was inversely correlated with height, and positively correlated with midday Ψ(l) , Ψ and shoot extension. The positive correlation between height and storage of NSC, and the negative correlation between NSC storage and shoot extension provide evidence that size-related growth decline in trees is not strongly associated with constraints on photosynthesis. The negative correlation between height and fluctuation in NSC suggests that mobilization of photosynthate in taller trees is constrained by some factor such as reductions in turgor-driven cell expansion or constraints on phloem transport.  相似文献   

13.
MOTIVATION: The nearest shrunken centroid (NSC) method has been successfully applied in many DNA-microarray classification problems. The NSC uses 'shrunken' centroids as prototypes for each class and identifies subsets of genes that best characterize each class. Classification is then made to the nearest (shrunken) centroid. The NSC is very easy to implement and very easy to interpret, however, it has drawbacks. RESULTS: We show that the NSC method can be interpreted in the framework of LASSO regression. Based on that, we consider two new methods, adaptive L(infinity)-norm penalized NSC (ALP-NSC) and adaptive hierarchically penalized NSC (AHP-NSC), with two different penalty functions for microarray classification, which improve over the NSC. Unlike the L(1)-norm penalty used in LASSO, the penalty terms that we consider make use of the fact that parameters belonging to one gene should be treated as a natural group. Numerical results indicate that the two new methods tend to remove irrelevant genes more effectively and provide better classification results than the L(1)-norm approach. AVAILABILITY: R code for the ALP-NSC and the AHP-NSC algorithms are available from authors upon request.  相似文献   

14.
温带森林不同树种具有不同的非结构性碳水化合物(NSC)存储和利用策略, 树干是成年树木NSC主体储存库。但树干NSC径向变异和种间差异仍不清楚, 无孔材(裸子植物)、散孔材和环孔材(被子植物)所代表的木材孔性功能群对树干NSC浓度的影响尚缺乏定论。为探索温带森林主要树种树干NSC浓度随树木木材孔性和组织的变化特征, 该研究在黑龙江省穆棱市的东北典型阔叶红松(Pinus koraiensis)林中选择32个树种, 采集胸高位置树皮、边材和心材3种组织, 分析NSC浓度随木材孔性和组织的变化特征。结果表明: (1)树种、组织和木材孔性均显著影响树干的NSC浓度。3种组织可溶性糖、淀粉、总NSC浓度和糖/淀粉的种间变异较大, 变异系数最低为37% (树皮总NSC浓度), 最高达到101% (心材淀粉浓度), 树干组织、树种及其交互作用均显著影响NSC浓度。(2)总体上可溶性糖、淀粉和总NSC浓度均随径向深度增加而降低。无孔材树皮的可溶性糖浓度和糖/淀粉显著高于散孔材和环孔材, 而边材中的淀粉和总NSC浓度为环孔材>散孔材>无孔材。(3)无孔材可溶性糖、淀粉和总NSC浓度边材和心材比均在1左右, 显著低于散孔材和环孔材, 而且无孔材边材和心材之间淀粉浓度相关较紧密, 表明被子植物的边材、心材功能分化较裸子植物更为明显。研究结果表明木材孔性影响了温带树种树干NSC存储策略, 研究整树NSC以及树木生理生态学功能需要区分树干组织。  相似文献   

15.
In this study, a Cu(2+) chelate of the novel thiosemicarbazone NSC 689534 was evaluated for in vitro and in vivo anti-cancer activity. Results demonstrated that NSC 689534 activity (low micromolar range) was enhanced four- to fivefold by copper chelation and completely attenuated by iron. Importantly, once formed, the NSC 689534/Cu(2+) complex retained activity in the presence of additional iron or iron-containing biomolecules. NSC 689534/Cu(2+) mediated its effects primarily through the induction of ROS, with depletion of cellular glutathione and protein thiols. Pretreatment of cells with the antioxidant N-acetyl-l-cysteine impaired activity, whereas NSC 689534/Cu(2+) effectively synergized with the glutathione biosynthesis inhibitor buthionine sulfoximine. Microarray analysis of NSC 689534/Cu(2+)-treated cells highlighted activation of pathways involved in oxidative and ER stress/UPR, autophagy, and metal metabolism. Further scrutiny of the role of ER stress and autophagy indicated that NSC 689534/Cu(2+)-induced cell death was ER-stress dependent and autophagy independent. Last, NSC 689534/Cu(2+) was shown to have activity in an HL60 xenograft model. These data suggest that NSC 689534/Cu(2+) is a potent oxidative stress inducer worthy of further preclinical investigation.  相似文献   

16.
近年来,森林食叶害虫在全世界呈爆发趋势.树木的非结构性碳水化合物(NSC)如何响应叶片损失对其生长和生存至关重要.雌雄异株植物在维持森林生态系统稳定性方面扮演着重要角色.然而,目前对该类植物性别之间如何响应去叶的研究还比较少.本文以我国重要的经济和生态恢复树种青杨(Populus cathayana)为研究材料,比较了...  相似文献   

17.
Implanted neural stem cells (NSC) could improve neurological functions following spinal cord injury (SCI), but the optimal conditions for NSC transplantation are largely unknown, especially in transected spinal cord. This study investigated the effect and fate of NSC engrafted into spinal cords at different locations and time points following T9 spinal cord transection. Engrafted NSC could survive and migrate in host spinal cords. Significant improvement in hindlimb locomotor functions associated with NSC survival was found in rats receiving NSC transplantation in the spinal cords rostral to the transection site at the subacute stage (7 days post operation), compared with those caudal to the transection site at the acute stage (at the time of injury). At 4 weeks post operation, CD68 immunohistochemical staining confirmed that macrophages were less in rostrally transplanted sites and in subacute groups than seen in caudal and acute transplanted rats. The present findings indicated that NSC transplantation into spinal cords rostral to transection site at the subacute stage is an optimal strategy for engrafted NSC survival and host behavioral improvement. It therefore would be available to the usage of NSC for the treatment of SCI in the future clinic trial.  相似文献   

18.
Sheath rot disease (ShR) caused by Sarocladium oryzae (S. oryzae) infection is an emerging disease that causes severe yield loss by restricting the translocation of non‐structural carbohydrates (NSC). Potassium (K) nutrition plays a critical role in disease resistance and the exportation of NSC. However, the physiological mechanisms of K with respect to ShR have not been thoroughly elucidated to date. The objectives of this study were to reveal the mechanisms by which K increases ShR resistance by regulating NSC translocation of rice, therefore, a field experiment combined with an inoculation experiment was conducted. We demonstrate that ShR disease incidence and disease index decreased dramatically with an increasing K application. K deficiency sharply induced the accumulation of NSC in the flag leaf (FL) and flag leaf sheath (FLS) under S. oryzae infection condition, which reduced the contribution of transferred NSC to final yield. A permutational multivariate analysis showed that K deficiency had a greater (49.0%, P < 0.001) effect on the NSC content variation in FL than that of S. oryzae infection (15.0%, P < 0.001). S. oryzae infection dramatically increased the difference in apparent transferred mass of NSC and cell membrane injury of diseased organs between K‐deficient and K‐sufficient rice. Finally, we demonstrate that cell membrane injury was a limiting factor imposed by K deficiency, which restricts the export of NSC from source organs. This work highlights the importance of K in improving ShR resistance by regulating NSC translocation (particularly the stem NSC).  相似文献   

19.
秦岭东段栓皮栎叶片非结构性碳水化合物含量的季节动态   总被引:1,自引:0,他引:1  
研究树木叶片非结构性碳水化合物(Nonstructural carbohydrate,NSC)组分的季节变化是掌握树木碳代谢规律的基础,也有利于判断以往研究仅凭生长季单次或几次(5次)的取样方法是否存在一定局限性。以秦岭东段栓皮栎(Quercus variabilis Blume)优势群落为研究对象,在其分布的海拔上下限(650 m和970 m),于2016年5月至2017年5月,通过月尺度周期性取样(共计9次),测定栓皮栎叶片NSC及其组分含量,并观测同期叶片物候变化。结果显示:(1)栓皮栎叶片NSC及其组分季节变化差异显著(P0.05),可溶性糖、淀粉和NSC变异系数分别为20.99%、52.28%和25.96%;(2)整体而言,栓皮栎叶片NSC最小值在展叶初期(3月末—4月初,5%左右),最大值在展叶末期(5月上旬,12%左右),之后NSC呈持续下降趋势。不同海拔NSC极值出现时间略有不同,叶片物候可能是影响年内极值的主要原因。(3)栓皮栎叶片NSC组成以可溶性糖为主(65%),这可能是树种在暖温带所采取的生长策略。(4)海拔对栓皮栎叶片NSC及其组分影响差异不显著,低海拔栓皮栎叶片NSC及其组分含量略大于高海拔。研究结果,栓皮栎叶片NSC含量存在明显的季节波动,适当加大NSC采样频率对于正确理解树木碳代谢十分必要。  相似文献   

20.
为探讨中国沙棘(Hippophae rhamnoides ssp.sinensis)伐桩萌枝的养分投资与分配机制,以陕西省定边县15a中国沙棘人工林为研究对象,设置不平茬(对照)和平茬高度0、10、20 cm处理,分析伐桩萌枝能力、非结构性碳水化合物(NSC)对平茬高度的响应规律及其因果关系.结果显示:(1)随平茬高度...  相似文献   

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