红小豆是我国重要的杂粮作物之一[1]，其苗期易受杂草影响，导致产量下降，因此，合理使用除草剂既可以控制杂草，又可以减少药害，达到有效种植，确保红小豆增收增产。氟磺胺草醚（fomesafen，FSA）又称虎威，属于二苯醚类除草剂，其主要作用于原卟啉原氧化酶[2]，因其除草效率高、选择性好[3]，可被杂草叶片及根部吸收，抑制杂草光合速率及对有机物和能量汲取，从而达到除草效果[4]，目前已广泛用于大豆[5]、番茄[6]、小麦[7]、草莓[8]和玉米[9]等田间阔叶类杂草的防除。研究[10]表明，用25% FSA·烯草酮乳油对绿豆和红小豆田间阔叶杂草防除效果较好。红小豆田间喷施25% FSA能使红小豆增产[11]。但田间喷施FSA影响大豆幼苗的光合速率[12]，抑制幼苗蔗糖代谢和碳代谢过程，阻碍同化产物的合成和运输，影响大豆根瘤的能量供应[13-14]。
代谢组学是系统生物学的一个分支，在研究环境因素作用下的特定代谢型具有较高的灵敏度，在环境变化对机体的影响研究等方面具有优势[15-16]。前人[17]研究表明，采用LC-MS技术分析乐果对小鼠的影响，在尿液中筛选出12种差异代谢物，在血浆中筛选出13种差异代谢物，且代谢物二甲基硫代磷酸和二甲基二硫代磷酸在所有的差异代谢物中最为显著。利用LC-MS方法检测吡虫啉对蜜蜂羽化出房时代谢物的影响，共鉴定出18种差异代谢物，主要调控鸟苷酸代谢和能量代谢等途径，对蜜蜂的生长发育产生显著影响[18]。利用代谢组学技术研究了恶唑烷酮对玉米幼苗代谢产物的影响，检测到90多种代谢产物，其中24种差异显著，这些差异代谢物参与玉米幼苗的能量和蛋白质代谢[19]。
1 材料与方法
1.1 试验材料
试验红小豆品种为珍珠红。试验试剂为25%氟磺胺草醚水剂；甲醇、乙腈、甲酸和异丙醇均为色谱纯，2-氯-L-苯丙氨酸（纯度≥98%）。
1.2 仪器与设备
试验所用设备如下，冷冻离心机（Centrifuge 5430 R）、多样品冷冻研磨仪（Wonbio-96 c）、台式快速离心浓缩干燥器（LNG-T 88）、氮气吹扫仪（JXDC-20）、UHPLC液相色谱系统（Vanquish Horizon system）、质谱仪（Q-ExactiveHF-X）。
1.3 试验设计
1.3.1 FSA胁迫红小豆种植试验及样品采集
挑选出籽粒大小均匀、饱满的红小豆种子，用去离子水洗去表面污渍后，浸泡于30% H2O2溶液中消毒5min，再用去离子水冲洗，直到泡沫完全消失，晾干后备用。根据除草剂FSA的推荐使用量进行红小豆萌发试验。每盆种50粒，每3盆为1个处理，每个处理3个重复，以未喷药为空白对照，待红小豆苗长到2~3叶时用除草剂FSA（0.3mL/m2）进行喷施，喷药次数为2次，间隔时间为14d，第2次喷药结束7d后，对红小豆幼苗进行采样（即红小豆幼苗为5叶时），采集未喷施FSA的红小豆幼苗为Z-2-ZZ组，喷施FSA的红小豆幼苗为Z-2-ZZ-2组，所有采集样品置于-20℃冰箱中储存备用。
1.3.2 样品处理
准确称取50mg样品至2mL离心管中，加入一颗直径为6mm的研磨珠和400µL提取液[甲醇:水=4:1（v:v）]，在冷冻组织研磨仪研磨6min（-10℃，50Hz），再用低温超声提取30min（5℃，40kHz），将样品于-20℃条件下静置30min，离心15min（13 000g，4℃），移取上清液至带内插管的进样小瓶中上机分析。最后每个样本分别移取20µL上清液混合后作为质控样本。
1.3.3 LC-MS检测
1.4 数据处理
使用ProgenesisQI（美国）软件进行峰提取等预处理，并将提取的特征峰在公共的代谢组数据库KEGG和HMDB进行搜库鉴定，匹配出的代谢集用ropls（R）软件进行多元统计分析，结合Student’s t检验的P<0.05和正交偏最小二乘―判别分析（OPLS-DA）中VIP>1筛选出差异代谢物，最后对代谢物进行KEGG通路富集分析。
2 结果与分析
2.1 FSA胁迫下红小豆幼苗主成分分析（PCA）
图1
图1
红小豆幼苗Z-2-ZZ-2组和Z-2-ZZ组主成分分析得分图
Fig.1
Scores of principal component analysis of adzuki bean seedlings in Z-2-ZZ-2 and Z-2-ZZ groups
2.2 FSA胁迫红小豆幼苗正交偏最小二乘判别分析（OPLS-DA）
图2
图2
红小豆幼苗Z-2-ZZ-2组和Z-2-ZZ组OPLS-DA置换检验结果
Fig.2
OPLS-DA replacement test results of adzuki bean seedlings in Z-2-ZZ-2 and Z-2-ZZ groups
2.3 FSA胁迫下红小豆幼苗差异代谢物数量和类别鉴定结果
由图3可知，红色点表示差异代谢物的表达量呈上调趋势，蓝色点表示差异代谢物的表达量呈下调趋势，越往左右两边，差异越显著。2种离子模式下分析出的代谢物数量极多，但多数仅有变化趋势，差异不显著。
图3
图3
FSA胁迫下红小豆幼苗差异代谢物火山图
Fig.3
Volcanic figure of different metabolites of adzuki bean seedlings under FSA stress
Z-2-ZZ-2与Z-2-ZZ相比，从数量上看，在P<0.05、VIP>1的条件下共筛选出236种差异代谢物，如表1和表2可知，正离子模式下，分析出有名称的代谢物106种，其中上调50种，下调56种；负离子模式下，分析出代谢物130种，其中上调42种，下调88种。从分类上看，正离子模式下，上调的差异代谢物主要是苯丙烷和聚酮化合物、有机化合物、脂质和类脂分子等，下调的差异代谢物主要是有机酸及其衍生物、脂质和类脂分子、有机杂环化合物、核苷、核苷酸及其类似物、苯丙烷和聚酮化合物等；负离子模式下，上调的差异代谢物主要是苯丙烷和聚酮化合物、脂质和类脂分子、有机氧化合物以及有机杂环化合物等，下调的差异代谢物主要是有机酸及其衍生物、脂质和类脂分子、有机氧化合物、核苷、核苷酸及其类似物、苯丙烷和聚酮化合物等。
表1 FSA胁迫下红小豆幼苗差异代谢物定性结果（正离子)
Table 1
| 化合物分类 Classification of compound | 差异代谢物总数量 Total quantity of differential metabolites | 显著上调 Significant up regulation | 显著下调 Significant down- regulation |
|---|---|---|---|
| 苯丙烷和聚酮化合物Phenylpropane and polyketone compounds | 13 | 10 | 3 |
| 苯类Benzene | 2 | 2 | 0 |
| 核苷、核苷酸和类似物Nucleosides, nucleotides and analogues | 3 | 0 | 3 |
| 均质非金属化合物Homogeneous non-metallic compound | 1 | 0 | 1 |
| 有机氮化合物Organic nitrogen compounds | 1 | 0 | 1 |
| 有机酸及其衍生物Organic acids and their derivatives | 11 | 0 | 11 |
| 有机氧化合物Organic oxygen compounds | 12 | 11 | 1 |
| 有机杂环化合物Organic heterocyclic compounds | 8 | 2 | 6 |
| 脂质和类脂分子Lipids and lipid molecules | 19 | 8 | 11 |
| 其他Others | 36 | 17 | 19 |
| 合计Total | 106 | 50 | 56 |
表2 FSA胁迫下红小豆幼苗差异代谢物定性结果（负离子)
Table 2
| 化合物分类 Classification of compound | 差异代谢物总数 Total quantity of differential metabolites | 显著上调 Significant up regulation | 显著下调 Significant down- regulation |
|---|---|---|---|
| 苯丙烷和聚酮化合物Phenylpropane and polyketone compounds | 14 | 10 | 4 |
| 苯类Benzene | 3 | 2 | 1 |
| 核苷、核苷酸和类似物Nucleosides, nucleotides and analogues | 4 | 0 | 4 |
| 有机氮化合物Organic nitrogen compounds | 1 | 0 | 1 |
| 有机酸及其衍生物Organic acids and their derivatives | 34 | 2 | 32 |
| 有机氧化合物Organic oxygen compounds | 12 | 7 | 5 |
| 有机杂环化合物Organic heterocyclic compounds | 10 | 7 | 3 |
| 脂质和类脂分子Lipids and lipid molecules | 40 | 10 | 30 |
| 其他Others | 12 | 4 | 8 |
| 合计Total | 130 | 42 | 88 |
2.4 FSA胁迫下红小豆幼苗差异代谢物代谢通路分析
植物的生长伴随着复杂的代谢过程，由多种小分子代谢物共同调控，并不能从单一物质含量变化对整体变化进行判断，因此需进一步对其代谢途径进行具体的分析[24]。将筛选出的差异代谢物与KEGG通路数据库信息进行匹配，对匹配到的代谢通路进行拓扑分析并绘制气泡图。由图4可知，正离子模式下，共分析出16条代谢通路；负离子模式下，共分析出12条代谢通路，再结合Impact值和P<0.05综合分析，筛选出差异显著的代谢通路以及参与相应通路的差异代谢物。如表3和表4可知，正离子模式下，富集到5条差异显著的代谢通路，分别是嘧啶代谢、异黄酮生物合成、嘌呤代谢、半乳糖代谢和精氨酸和脯氨酸代谢，映射出13种差异代谢物，其中差异代谢物尿嘧啶和胞嘧啶参与嘧啶代谢的代谢途径，2,7,4′-三羟基异黄酮、甘氨酸和毛蕊异黄酮参与了异黄酮生物合成，鸟嘌呤、次黄嘌呤和β-谷甾酮参与嘌呤代谢，甘露三糖和蔗糖参与了半乳糖代谢，4-（谷氨酰胺）丁酸酯、对香豆酰腐胺和（2 S）-2-（3-羧基丙酰氨基）-5-氧代戊酸参与了精氨酸和脯氨酸代谢；负离子模式下，富集到2条差异显著的代谢通路，映射出5种差异代谢物，分别是花青素生物合成和黄酮类生物合成，其中差异代谢物矢车菊素-3-葡萄糖苷和花葵素参与了花青素生物合成，根皮苷、（2 R,3 R）-3,4′,7-三羟基黄烷酮、花葵素和香树脂参与了黄酮类生物合成。
图4
图4
FSA胁迫下红小豆幼苗代谢途径拓扑分析气泡图
气泡表示通路；Impact value表示通路的重要性；-Log10P表示富集显著性
Fig.4
Bubble diagram of topological analysis of metabolic pathway of adzuki bean seedlings under FSA stress
The bubbles in the figure represent the path; Impact value indicates the importance of the path -Log10P indicates enrichment significance
表3 FSA胁迫下红小豆幼苗代谢通路富集结果（正离子）
Table 3
| 通路名称 Path name | 通路代谢物总数 Total pathway metabolites | 富集代谢物个数 Number of enriched metabolites | P值 P-value | Impact值 Impact value | 代谢物名称及KEGG ID Metabolite name and KEGG ID |
|---|---|---|---|---|---|
| 嘧啶代谢 Pyrimidine metabolism | 62 | 2 | 0.0235 | 0.1239 | 尿嘧啶C00106；胞嘧啶C00380 |
| 异黄酮生物合成 Isoflavone biosynthesis | 49 | 3 | 0.0007 | 0.1078 | 2,7,4'-三羟基异黄酮C15567；甘氨酸C16195；毛蕊异黄酮C01562 |
| 嘌呤代谢 Purine metabolism | 81 | 3 | 0.0031 | 0.0796 | 鸟嘌呤C00242；次黄嘌呤C00262；β-谷甾酮C00014 |
| 半乳糖代谢 Galactose metabolism | 46 | 2 | 0.0136 | 0.0153 | 甘露三糖C05404；蔗糖C00089 |
| 精氨酸和脯氨酸代谢 Arginine and proline metabolism | 72 | 3 | 0.0022 | 0.0073 | 4-(谷氨酰胺)丁酸酯C15767；对香豆酰腐胺C18326；(2 S)-2-(3-羧基丙酰氨基)-5-氧代戊酸C05932 |
表4 FSA胁迫下红小豆幼苗代谢通路富集结果（负离子）
Table 4
| 通路名称 Path name | 通路代谢物总数 Total pathway metabolites | 富集代谢物个数 Number of enriched metabolites | P值 P-value | Impact值 Impact value | 代谢物名称及KEGG ID Metabolite name and KEGG ID |
|---|---|---|---|---|---|
| 花青素生物合成 Anthocyanin biosynthesis | 41 | 2 | 0.0147 | 0.1284 | 矢车菊素-3-葡萄糖苷C12137；花葵素C05904 |
| 黄酮类生物合成 Flavonoid biosynthesis | 68 | 4 | 0.0030 | 0.0208 | 根皮苷C01604；花葵素C05904；香树脂C00974；(2 R,3 R)-3,4',7-三羟基黄烷酮C09751 |
由图4可知，颜色越红，P值越小，说明通路越显著，气泡越大，通路越重要。正离子模式下，嘧啶代谢途径、异黄酮生物合成途径和嘌呤代谢途径的气泡相对较大，说明这3条通路在分析FSA对红小豆幼苗代谢途径的影响较为重要，其次，半乳糖代谢和精氨酸和脯氨酸代谢的气泡相对较小，说明FSA对红小豆幼苗代谢途径的影响也有一定的重要性；负离子模式下，花青素生物合成途径的气泡较大，说明FSA对红小豆幼苗的花青素生物合成影响较大，通路较为重要，黄酮类生物合成途径的气泡稍小，说明FSA对红小豆幼苗中黄酮类物质的合成有显著影响。
3 讨论
植物中产生的次级代谢产物主要用于应对不良环境条件，如黄酮类物质、萜类化合物和生物碱等，它们对非生物的胁迫具有耐受性[25]。红小豆田间喷施FSA，主要对红小豆幼苗中苯丙烷和聚酮类化合物、脂质和类脂分子类化合物以及有机酸及其衍生物类化合物产生显著影响。苯丙烷和聚酮类化合物中的差异代谢物主要是黄酮类化合物，研究[26]表明，黄酮类化合物是豆类中的一种酚类化合物，具有调理细胞分化、凋亡、抗自由基等作用[27-28]，红小豆田间喷施FSA能刺激红小豆幼苗产生次级代谢产物中的黄酮类物质，促进红小豆幼苗的生长代谢。植物根系分泌有机酸是为了适应环境胁迫，红小豆幼苗生长过程中受除草剂FSA的胁迫，产生的有机酸释放到根际土壤中，从而改变土壤环境，例如土壤的理化性质和微生物活性等[29⇓-31]，为红小豆幼苗的生长提供养分和能量，并且有机酸及其衍生物化合物中的羧酸及其衍生物属于萜类化合物，具有抵御FSA胁迫的作用。
糖类物质能为植物的细胞代谢提供碳源和能量[32]。本研究发现，参与半乳糖代谢途径的差异代谢物——蔗糖的表达量显著下调，与程茁等[14]的研究结果一致，糖代谢为氨基酸代谢提供能量[33]，因此，氨基酸代谢中的精氨酸和脯氨酸代谢也受一定的影响。嘌呤和嘧啶主要以核苷酸的形式存在，而参与精氨酸和脯氨酸代谢的差异代谢物4-（谷氨酰胺）丁酸酯为嘌呤和嘧啶核苷酸类化合物的合成提供一部分氮源[34]。嘌呤和嘧啶属于生物碱，生物碱的合成和积累受生物和非生物的调控[35]，本研究中嘌呤代谢和嘧啶代谢途径富集到的差异代谢物尿嘧啶、胞嘧啶、鸟嘌呤、次黄嘌呤等的表达量在FSA胁迫下发生显著下调，喷施FSA抑制了红小豆幼苗的嘌呤代谢和嘧啶代谢。此外，植物类黄酮能使植物抵御外界环境的压迫[25,36]，喷施FSA能促进红小豆幼苗中黄酮类物质的合成。花青素属于黄酮类化合物，是一种天然色素，幼苗的花色由各种花青素的比例决定，矢车菊素-3-葡萄糖苷和花葵素分别产生红色和橙色的花[37]，但花青素生物合成容易受外界因素的影响[38]，红小豆田间喷施FSA显著影响红小豆幼苗中花青素的生物合成。
4 结论
采用LC-MS代谢组学技术分析红小豆幼苗受FSA胁迫后代谢物的变化具有可行性。结果表明，FSA对红小豆幼苗代谢产物的种类和数量都有显著影响，主成分分析显示，Z-2-ZZ-2组和Z-2-ZZ组之间存在代谢组学差异，经多元统计分析后，共筛选出236种差异代谢物，且多数呈现下调趋势，说明红小豆田间喷施FSA对红小豆幼苗的生长代谢造成显著影响。
KEGG通路分析发现，除草剂FSA对红小豆幼苗的生长代谢途径有显著影响，正离子模式下，差异显著且最为重要的通路是嘧啶代谢和异黄酮生物合成，负离子模式下，差异显著且最为重要的通路是花青素生物合成。本研究中筛选出7条差异显著的代谢通路中有3条（异黄酮生物合成、花青素生物合成和黄酮类生物合成）与红小豆幼苗中黄酮类化合物的合成有关，喷施FSA对红小豆幼苗中黄酮类物质的影响较大，黄酮类化合物是通路分析的关键代谢物。
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URL
[本文引用: 1]
Fomesafen is a protoporphyrinogen oxidase–inhibitor herbicide with an alternative mode of action that provides PRE weed control in strawberry [Fragaria×ananassa(Weston) Duchesne ex Rozier (pro sp.) [chiloensis×virginiana]] produced in a plasticulture setting in Florida. Plasticulture mulch could decrease fomesafen dissipation and increase crop injury in rotational crops. Field experiments were conducted in Balm, FL, to investigate fomesafen persistence and movement in soil in Florida strawberry systems for the 2014/2015 and 2015/2016 production cycles. Treatments included fomesafen preplant at 0, 0.42, and 0.84 kg ai ha−1. Soil samples were taken under the plastic from plots treated with fomesafen at 0.42 kg ha−1throughout the production cycle. Fomesafen did not injure strawberry or decrease yield. Fomesafen concentration data for the 0.0- to 0.1-m soil depth were described using a three-parameter logistic function. The fomesafen 50% dissipation times were 37 and 47 d for the 2014/2015 and 2015/2016 production cycles, respectively. At the end of the study, fomesafen was last detected in the 0.0- to 0.1-m depth soil at 167 and 194 d after treatment in the 2014/2015 and 2015/2016 production cycles, respectively. Fomesafen concentration was less than 25 ppb on any sampling date for 0.1- to 0.2-m and 0.2- to 0.3-m depths. Fomesafen concentration decreased significantly after strawberry was transplanted and likely leached during overhead and drip irrigation used during the crop establishment.
Dissipation of fomesafen in biochar-amended soil and its availability to corn (Zea mays L.) and earthworm (Eisenia fetida)
DOI:10.1007/s11368-016-1407-4 URL [本文引用: 1]
Metabolomics the link between genotypes and phenotypes
DOI:10.1023/A:1013713905833 URL [本文引用: 1]
代谢组学在水稻研究中的应用进展
DOI:10.13304/j.nykjdb.2017.0068
[本文引用: 1]
代谢组学是系统生物学重要的分支，通过对小分子代谢物的研究来揭示生命体的生理状态，进而探索生命活动的规律。对代谢组学进行了简单概述，介绍了代谢组学常用的分析平台，综述了代谢组学在水稻响应非生物和生物胁迫、基因功能、辅助育种及转基因安全研究中的应用现状，并就存在的挑战和机遇进行了分析，以期为代谢组学应用于水稻研究提供参考。
Metabonomics analysis of urine and plasma from rats given long-term and low-dose dimethoate by ultra-performance liquid chromatography-mass spectrometry
DOI:10.1016/j.cbi.2012.07.004
PMID:22884955
[本文引用: 1]
This study assessed the effects of long-term, low-dose dimethoate administration to rats by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Dimethoate (0.04, 0.12, and 0.36 mg/kg body weight/day) was administered daily to male Wistar rats through their drinking water for 24 weeks. Significant changes in serum clinical chemistry were observed in the middle- and high-dose groups. UPLC-MS revealed evident separate clustering among the different dose groups using global metabolic profiling by supervised partial least squares-discriminant analysis. Metabonomic analysis showed alterations in a number of metabolites (12 from urine and 13 from plasma), such as L-tyrosine, dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), citric acid, uric acid, suberic acid, glycylproline, allantoin, isovalerylglutamic acid and kinds of lipids. The results suggest that long-term, low-dose exposure to dimethoate can cause disturbances in liver function, antioxidant and nervous systems, as well as the metabolisms of lipids, glucose, fatty acids, amino acids, and collagen in rats. DMTP and DMDTP, which had the most significant changes among all other studied biomarkers, were considered as early, sensitive biomarkers of exposure to dimethoate. The other aforementioned proposed toxicity biomarkers in metabonomic analysis may be useful in the risk assessment of the toxic effects of dimethoate. Metabonomics as a systems toxicology approach was able to provide comprehensive information on the dynamic process of dimethoate induced toxicity. In addition, the results indicate that metabonomic approach could detect systemic toxic effects at an earlier stage compared to clinical chemistry. The combination of metabonomics and clinical chemistry made the toxicity of dimethoate on rats more comprehensive.Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
基于非靶向代谢组学的白茶与绿茶、乌龙茶和红茶代谢产物特征比较
DOI:10.7506/spkx1002-6630-20190128-358
[本文引用: 1]
探究白茶的代谢物特征及其形成的加工学原理，以福云六号和黄旦茶树品种一芽二三叶鲜叶为原料，按照白茶、绿茶、乌龙茶和红茶加工方法制成相应茶类。使用超高效液相色谱-四极杆飞行时间质谱测定鲜叶样品和不同茶类中全部代谢物丰度，并对代谢物进行筛选和鉴定。结果表明，2 个品种制成的不同茶类之间代谢差异物共筛选出152 个和148 个，其中33 个茶叶中主要物质得到鉴定，这些物质属于儿茶素及其衍生物类、花青素类、水解单宁类、黄酮醇或黄酮糖苷类、酚酸类和茶黄素类。主成分分析表明白茶在第1主成分上介于乌龙茶和红茶之间，在第2主成分上区别于其他茶类。载荷图显示黄酮醇或黄酮糖苷类物质、酯型儿茶素和儿茶素衍生物是白茶区别于其他茶类的特征代谢产物。从物质丰度上看，白茶中大部分黄酮醇或黄酮糖苷类物质显著高于其他茶类；儿茶素和花青素显著低于绿茶并接近红茶，特别是非酯型儿茶素；茶黄素和茶黄素-3-没食子酸酯高于绿茶，但茶黄素-3’-没食子酸酯和茶黄素-3,3’-没食子酸酯与绿茶相比无显著差异；儿茶素衍生物8-C-抗坏血酸基-表没食子儿茶素没食子酸酯显著高于其他茶类。
Metabolomics: a way forward for crop improvement
DOI:10.3390/metabo9010001
URL
[本文引用: 2]
To evaluate the taste of ordinary muscle from white-fleshed fish, we used GC-MS metabolomic analysis to characterise the compounds therein, and correlated the obtained data with taste measurements from an electronic tongue. Prediction models using orthogonal partial least squares were produced for different taste attributes, and the primary metabolic components correlated with the taste attributes were identified. Clear differences were observed in the component profiles for different fish species. Using an electronic tongue, differences in tastes were noted among the fish species in terms of sourness, acidic bitterness, umami and saltiness. The obtained correlations allowed the construction of good taste prediction models, especially for sourness, acidic bitterness and saltiness. Compounds such as phosphoric acid, lactic acid and creatinine were found to be highly correlated with some taste attributes. Phosphoric acid in particular showed the highest variable important for prediction (VIP) scores in many of the taste prediction models, and it is therefore a candidate marker to evaluate the tastes of white-fleshed fish.
Flavonoid biosynthetic pathways in plants: Versatile targets for metabolic engineering
Naturally occurring chalcones and their biological activities
DOI:10.1007/s11101-014-9387-8 URL [本文引用: 1]
Exploring the temperature- stress metabolome of arabidopsis
DOI:10.1104/pp.104.052142
URL
[本文引用: 1]
Metabolic profiling analyses were performed to determine metabolite temporal dynamics associated with the induction of acquired thermotolerance in response to heat shock and acquired freezing tolerance in response to cold shock. Low-Mr polar metabolite analyses were performed using gas chromatography-mass spectrometry. Eighty-one identified metabolites and 416 unidentified mass spectral tags, characterized by retention time indices and specific mass fragments, were monitored. Cold shock influenced metabolism far more profoundly than heat shock. The steady-state pool sizes of 143 and 311 metabolites or mass spectral tags were altered in response to heat and cold shock, respectively. Comparison of heat- and cold-shock response patterns revealed that the majority of heat-shock responses were shared with cold-shock responses, a previously unknown relationship. Coordinate increases in the pool sizes of amino acids derived from pyruvate and oxaloacetate, polyamine precursors, and compatible solutes were observed during both heat and cold shock. In addition, many of the metabolites that showed increases in response to both heat and cold shock in this study were previously unlinked with temperature stress. This investigation provides new insight into the mechanisms of plant adaptation to thermal stress at the metabolite level, reveals relationships between heat- and cold-shock responses, and highlights the roles of known signaling molecules and protectants.
棉花在盐碱胁迫下代谢产物及通路的分析
DOI:10.3724/SP.J.1006.2022.14110
[本文引用: 1]
阐明植物盐碱胁迫下的代谢机制将有助于进一步优化育种和栽培, 从而提高盐碱地作物产量。本研究采用液相色谱-质谱(LC-MS), 对中性盐和碱性盐胁迫下棉花叶片代谢产物进行研究, 分析棉花在盐碱胁迫下的代谢差异。结果显示, 盐胁迫下棉花叶片中糖类在正负离子模式下分别有7种和2种上调, 氨基酸类各有3种上调, 有机酸类分别有12种和8种上调; 碱胁迫下棉花叶片中的糖类分别有3种和5种上调, 有机酸类分别有2种和9种上调, 氨基酸类各有2种上调。盐胁迫下发现10条差异代谢通路, 变化最明显的代谢通路是亚油酸代谢, 其次是淀粉和蔗糖代谢与精氨酸生物合成; 碱胁迫下发现5条差异代谢通路, 变化最明显的代谢通路是色氨酸代谢, 其次是精氨酸和脯氨酸代谢与柠檬酸循环(TCA循环)。棉花采取不同的代谢机制抵抗盐碱胁迫, 盐胁迫更倾向于积累糖类, 碱胁迫更倾向于积累有机酸; 在能量代谢方面, 盐胁迫下棉花淀粉和蔗糖代谢更加活跃, 碱胁迫下TCA循环更加活跃; 盐胁迫提高了棉花氮素同化能力, 碱胁迫降低了氮的同化能力。
The cell and developmental biology of alkaloid biosynthesis
Plants produce unique natural products as a result of gene mutation and subsequent adaptation of metabolic pathways to create new secondary metabolites. However, their biosynthesis and accumulation remains remarkably under the control of the biotic and abiotic environments. Alkaloid biosynthesis, which requires the adaptation of cellular activities to perform specialized metabolism without compromising general homeostasis, is accomplished by restricting product biosynthesis and accumulation to particular cells and to defined times of plant development. The cell and developmental biology of alkaloid biosynthesis, which is remarkably complex, evolved in part by recruiting pre-existing enzymes to perform new functions.
