通路拓扑影响:完整技术报告

主要发现:在 KEGG 反应网络上计算影响值:45 个比较中至少有 1 条通路 FDR<0.05 的,酶(基因)网络 13 个、联合网络 9 个、代谢物网络 2 个;类黄酮生物合成在酶网络上的影响值最高达 0.88。

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1 分析目的

富集分析只看一条通路里差异分子的数量,不区分它们处在通路的什么位置。处在多条代谢路线交汇处的分子(如分支点化合物、关键酶)变化时,对整条通路的影响通常更大。通路拓扑影响分析把“差异分子在通路网络中的位置重要性”量化为影响值(Pathway Impact),与富集显著性一起判断哪些通路既显著又关键。本流程在同一套 KEGG 反应网络上分别计算代谢物、基因(酶)和两者联合的影响值,并对照三者的一致程度。

2 分析原理

1. 通路网络(来自 KEGG KGML,真实拓扑):每条通路的 KGML 文件给出反应(R 编号)、催化反应的酶(KO 编号)以及反应的底物和产物(化合物 C 编号)。ATP、NADH、H₂O、CO₂ 等通用辅因子和小分子不作为节点。在此基础上构建三种有向网络:

2. 中心性:相对介数中心性(relative betweenness centrality)。节点 v 的介数 B(v) = Σs≠v≠t σst(v)/σst,σst 为 s 到 t 的最短路径条数,σst(v) 为其中经过 v 的条数;有向图的相对值为 B(v)/[(n−1)(n−2)],n 为通路节点数。用 Brandes 算法计算,并在验收中用 igraph 独立复算。

3. 影响值:节点重要性 wv = 中心性 / 通路内全部节点中心性之和(全部节点之和为 1)。

Impactp = Σv ∈ 命中节点 wv

取值 0–1。基因层的命中节点为至少有 1 个差异基因注释到该 KO 的节点;代谢物层为至少有 1 个差异代谢物注释到该化合物的节点;联合层两者都算。通路内没有任何中介节点(全部中心性为 0)时影响值不可计算,记为 NA。联合层的影响值是在联合网络上直接计算的,不是把两个组学的影响值相加、平均或加权。

4. 富集 P 值:节点水平的超几何检验(与 MetPA 的 ORA 一致)。N 为全部可分析通路中已检测的节点数,K 为该通路已检测节点数,n 为背景中的命中节点数,k 为该通路的命中节点数,P 为上尾概率。联合层把 KO 节点和化合物节点放在同一背景中检验(MetaboAnalyst 联合通路分析的 “combine queries” 方式)。FDR 在每个比较、每一层内对全部可检验通路做 BH 校正。

5. 覆盖率:已检测节点数 / 通路节点总数,说明该通路在本数据中能被观测到的比例;覆盖率低的通路,影响值和 P 值都不可靠。

3 输入数据及预处理

通路数据库:KEGG 参考通路(ko / map)KGML,快照版本见“方法与软件”页;纳入范围与 KEGG 联合富集相同(去掉总览图和人类疾病、器官系统、药物开发类,只保留 7 种代表植物至少一种具有的通路,排除 ko00965)。物种尚未确认,因此使用参考通路而不是某个物种的专属通路,部分节点在本物种中可能不存在。

分子映射:基因经服务商注释的 KO 映射到酶节点;代谢物经服务商注释的 KEGG 化合物编号映射到化合物节点。

已检测与命中:每个比较中,有检验结果的基因所在 KO、至少一组检出的代谢物所在化合物视为已检测;其中有差异分子的节点为命中。差异标准与“差异总览”页相同。

分析单位:影响值依赖差异分子列表,因此按比较计算;没有“全部 30 个样本”版本。跨比较的热图只是把各比较的结果并列展示,不合并统计量。

4 软件、算法及参数

软件 / 函数版本用途与关键参数
Python3.11.18KGML 反应表解析、三种网络构建、Brandes 介数中心性(有向、无权,除以 (n−1)(n−2))
scipy.stats.hypergeom—节点水平超几何检验(上尾)
igraph2.3.4验收时独立复算介数中心性和影响值
ggplot2 / pheatmap4.0.3 / 1.0.13影响值气泡图、共同通路对照图、跨比较热图(色标 0–0.5)
参数—中心性 relative_betweenness;通路节点少于 3 个不计算

5 统计指标解释

下表列出本页出现的全部统计指标和缩写(由页面内容自动生成)。全部术语见术语表。

术语中文名英文名定义与读法
PP 值P value在原假设(无差异、无相关或无富集)成立时,得到当前或更极端结果的概率,未经多重检验校正。
FDR错误发现率false discovery rate多重检验校正指标,表示在所有判为显著的结果中,预期假阳性所占比例。本报告全部用 Benjamini–Hochberg 方法计算,检验范围在各分析中分别说明(如“该比较的全部配对”“全部可评估通路”)。
BHBenjamini–Hochberg 校正Benjamini–Hochberg procedure把 m 个 P 值从小到大排序,第 i 个的校正值为 min(1, min_{k≥i} P_(k)·m/k)。控制 FDR,比 Bonferroni 校正宽松。
NA缺失值not available没有数值。未检出、未检验或不可计算时记为 NA,不当作 0。
KEGG京都基因与基因组百科全书Kyoto Encyclopedia of Genes and Genomes代谢通路和分子功能数据库。本流程用 KEGG 通路、KO、化合物(C 编号)和反应(R 编号)注释。
KOKEGG 直系同源编号KEGG OrthologyK 开头的编号,把不同物种的同功能基因归为一类,用于把基因映射到通路。
ORA过表达分析over-representation analysis检验差异分子在某通路中是否多于随机期望,本流程用超几何检验。
Pathway Impact通路拓扑影响值pathway impact差异分子在通路网络中的位置重要性之和。本流程按 MetPA 方法:在 KEGG 反应网络上计算每个节点的相对介数中心性,归一化为节点重要性(通路内之和为 1),影响值 = 命中节点重要性之和,0–1;越大说明差异分子越集中在通路的关键位置。代谢物、酶(基因)、联合网络三层分别计算,不相加。
WGCNA加权基因共表达网络分析weighted gene co-expression network analysis把相关矩阵经软阈值幂次变换成加权网络,用拓扑重叠聚类得到共表达模块。
KGMLKEGG 标记语言文件KEGG Markup LanguageKEGG 通路图的 XML 描述文件,记录每个节点的 KO 或化合物编号、坐标以及反应的底物和产物。
MetPA代谢通路分析Metabolomics Pathway Analysis结合超几何富集和通路拓扑(相对介数中心性)的代谢通路分析方法,MetaboAnalyst 的通路分析模块即基于此方法。
betweenness介数中心性betweenness centrality网络中经过某节点的最短路径所占的比例之和,衡量节点作为“桥梁”的作用;相对介数中心性在有向图中再除以 (n−1)(n−2)。
coverage通路覆盖率pathway coverage通路网络中在本数据已检测到的节点数 / 节点总数。

6 图表与结果展示

全局结果

影响值汇总共 135 行下载全表

表注:comparison 比较;layer 网络层;pathways 可检验通路数;with_hits 有命中节点的通路数;fdr_lt_005 FDR<0.05 的通路数;impact_gt_0 影响值大于 0 的通路数;max_impact 最大影响值。

comparisonlayerpathwayswith_hitsfdr_lt_005impact_gt_0max_impactcategory
R1_vs_R2gene955040.06359B_R组内跨水平
R1_vs_R2joint965050.02476B_R组内跨水平
R1_vs_R2met950000B_R组内跨水平
R1_vs_R3gene950000B_R组内跨水平
R1_vs_R3joint963030.03202B_R组内跨水平
R1_vs_R3met953030.05893B_R组内跨水平
R1_vs_R4gene95801651B_R组内跨水平
R1_vs_R4joint96810790.3667B_R组内跨水平
R1_vs_R4met957030.08123B_R组内跨水平
R1_vs_R5gene95880751B_R组内跨水平
R1_vs_R5joint96891880.4063B_R组内跨水平
R1_vs_R5met9520080.08123B_R组内跨水平
R1_vs_Y1gene95803680.8812A_同水平处理间
R1_vs_Y1joint96810800.4138A_同水平处理间
R1_vs_Y1met9511060.1212A_同水平处理间
R1_vs_Y2gene95820680.8889D_跨水平跨处理
R1_vs_Y2joint96820810.4091D_跨水平跨处理
R1_vs_Y2met959060.2399D_跨水平跨处理
R1_vs_Y3gene95810691D_跨水平跨处理
R1_vs_Y3joint96820800.4545D_跨水平跨处理
R1_vs_Y3met9510040.05958D_跨水平跨处理
R1_vs_Y4gene95820721D_跨水平跨处理
R1_vs_Y4joint96830820.4545D_跨水平跨处理
R1_vs_Y4met95310130.3253D_跨水平跨处理
R1_vs_Y5gene95861741D_跨水平跨处理
R1_vs_Y5joint96861850.4545D_跨水平跨处理
R1_vs_Y5met95180110.2399D_跨水平跨处理
R2_vs_R3gene950000B_R组内跨水平
R2_vs_R3joint962020.02426B_R组内跨水平
R2_vs_R3met952020.0543B_R组内跨水平
R2_vs_R4gene95740621B_R组内跨水平
R2_vs_R4joint96760740.2985B_R组内跨水平
R2_vs_R4met957060.09123B_R组内跨水平
R2_vs_R5gene95860721B_R组内跨水平
R2_vs_R5joint96860850.4063B_R组内跨水平
R2_vs_R5met9511070.09123B_R组内跨水平
R2_vs_Y1gene95762610.7999D_跨水平跨处理
R2_vs_Y1joint96780760.3773D_跨水平跨处理
R2_vs_Y1met959050.06323D_跨水平跨处理
R2_vs_Y2gene95750630.8889A_同水平处理间
R2_vs_Y2joint96760750.4088A_同水平处理间
R2_vs_Y2met9511180.09786A_同水平处理间
R2_vs_Y3gene95790650.8889D_跨水平跨处理
R2_vs_Y3joint96810790.3871D_跨水平跨处理
R2_vs_Y3met95231120.1173D_跨水平跨处理
R2_vs_Y4gene95820681D_跨水平跨处理
R2_vs_Y4joint96840820.4091D_跨水平跨处理
R2_vs_Y4met95150100.1111D_跨水平跨处理
R2_vs_Y5gene95860741D_跨水平跨处理
R2_vs_Y5joint96861850.4371D_跨水平跨处理
R2_vs_Y5met95180120.1611D_跨水平跨处理
R3_vs_R4gene95822731B_R组内跨水平
R3_vs_R4joint96832820.3993B_R组内跨水平
R3_vs_R4met95180140.1151B_R组内跨水平
R3_vs_R5gene95871741B_R组内跨水平
R3_vs_R5joint96870860.422B_R组内跨水平
R3_vs_R5met95220120.08797B_R组内跨水平
R3_vs_Y1gene95811660.8889D_跨水平跨处理
R3_vs_Y1joint96830810.3773D_跨水平跨处理
R3_vs_Y1met9510050.06323D_跨水平跨处理
R3_vs_Y2gene95790651D_跨水平跨处理
R3_vs_Y2joint96800780.3425D_跨水平跨处理
R3_vs_Y2met9511060.3021D_跨水平跨处理
R3_vs_Y3gene95790681A_同水平处理间
R3_vs_Y3joint96810790.3658A_同水平处理间
R3_vs_Y3met9513060.144A_同水平处理间
R3_vs_Y4gene95820691D_跨水平跨处理
R3_vs_Y4joint96850820.4091D_跨水平跨处理
R3_vs_Y4met95360190.3253D_跨水平跨处理
R3_vs_Y5gene95862741D_跨水平跨处理
R3_vs_Y5joint96861850.4071D_跨水平跨处理
R3_vs_Y5met95220150.08219D_跨水平跨处理
R4_vs_R5gene95632440.875B_R组内跨水平
R4_vs_R5joint96652640.4348B_R组内跨水平
R4_vs_R5met9510080.1887B_R组内跨水平
R4_vs_Y1gene95830691D_跨水平跨处理
R4_vs_Y1joint96860840.5682D_跨水平跨处理
R4_vs_Y1met95310210.25D_跨水平跨处理
R4_vs_Y2gene95840691D_跨水平跨处理
R4_vs_Y2joint96860830.5227D_跨水平跨处理
R4_vs_Y2met95270200.1288D_跨水平跨处理
R4_vs_Y3gene95820691D_跨水平跨处理
R4_vs_Y3joint96860830.3636D_跨水平跨处理
R4_vs_Y3met95370230.144D_跨水平跨处理
R4_vs_Y4gene95871711A_同水平处理间
R4_vs_Y4joint96881870.4091A_同水平处理间
R4_vs_Y4met95210110.141A_同水平处理间
R4_vs_Y5gene95810741D_跨水平跨处理
R4_vs_Y5joint96830830.5227D_跨水平跨处理
R4_vs_Y5met95220130.1288D_跨水平跨处理
R5_vs_Y1gene95850721D_跨水平跨处理
R5_vs_Y1joint96870850.5682D_跨水平跨处理
R5_vs_Y1met95330150.25D_跨水平跨处理
R5_vs_Y2gene95880731D_跨水平跨处理
R5_vs_Y2joint96890870.5682D_跨水平跨处理
R5_vs_Y2met95310180.3021D_跨水平跨处理
R5_vs_Y3gene95850700.608D_跨水平跨处理
R5_vs_Y3joint96880840.5D_跨水平跨处理
R5_vs_Y3met95340180.141D_跨水平跨处理
R5_vs_Y4gene95891731D_跨水平跨处理
R5_vs_Y4joint96901880.5682D_跨水平跨处理
R5_vs_Y4met95250120.141D_跨水平跨处理
R5_vs_Y5gene95830701A_同水平处理间
R5_vs_Y5joint96840830.5682A_同水平处理间
R5_vs_Y5met95220140.1682A_同水平处理间
Y1_vs_Y2gene950000C_Y组内跨水平
Y1_vs_Y2joint962010.01239C_Y组内跨水平
Y1_vs_Y2met952010.03454C_Y组内跨水平
Y1_vs_Y3gene952010.005368C_Y组内跨水平
Y1_vs_Y3joint9614190.04842C_Y组内跨水平
Y1_vs_Y3met9513060.1658C_Y组内跨水平
Y1_vs_Y4gene95730561C_Y组内跨水平
Y1_vs_Y4joint96770740.2295C_Y组内跨水平
Y1_vs_Y4met95320130.3253C_Y组内跨水平
Y1_vs_Y5gene95732581C_Y组内跨水平
Y1_vs_Y5joint96750750.2639C_Y组内跨水平
Y1_vs_Y5met95220160.1212C_Y组内跨水平
Y2_vs_Y3gene950000C_Y组内跨水平
Y2_vs_Y3joint961010.01121C_Y组内跨水平
Y2_vs_Y3met951010.00546C_Y组内跨水平
Y2_vs_Y4gene95660491C_Y组内跨水平
Y2_vs_Y4joint96700690.2295C_Y组内跨水平
Y2_vs_Y4met95200120.3021C_Y组内跨水平
Y2_vs_Y5gene95760571C_Y组内跨水平
Y2_vs_Y5joint96760750.2398C_Y组内跨水平
Y2_vs_Y5met9510070.06323C_Y组内跨水平
Y3_vs_Y4gene95630381C_Y组内跨水平
Y3_vs_Y4joint96700630.2309C_Y组内跨水平
Y3_vs_Y4met95280120.3253C_Y组内跨水平
Y3_vs_Y5gene95761601C_Y组内跨水平
Y3_vs_Y5joint96770760.3459C_Y组内跨水平
Y3_vs_Y5met95200140.08219C_Y组内跨水平
Y4_vs_Y5gene95720600.4469C_Y组内跨水平
Y4_vs_Y5joint96740720.1651C_Y组内跨水平
Y4_vs_Y5met956030.05958C_Y组内跨水平
通路网络共 288 行下载全表

表注:pid、name 通路;layer 网络层;n_nodes、n_edges 节点数和边数;sum_betweenness 相对介数中心性之和;analyzable 影响值是否可计算(节点数达到下限且存在中介节点)。

pidnamelayern_nodesn_edgessum_betweennessanalyzable
00010Glycolysis / Gluconeogenesismet30603.026是
00010Glycolysis / Gluconeogenesisgene10913172.064是
00010Glycolysis / Gluconeogenesisjoint1393984.748是
00020Citrate cycle (TCA cycle)met19432.536是
00020Citrate cycle (TCA cycle)gene709181.314是
00020Citrate cycle (TCA cycle)joint892903.808是
00030Pentose phosphate pathwaymet37812.064是
00030Pentose phosphate pathwaygene958381.221是
00030Pentose phosphate pathwayjoint1323293.116是
00040Pentose and glucuronate interconversionsmet591153.452是
00040Pentose and glucuronate interconversionsgene974633.015是
00040Pentose and glucuronate interconversionsjoint1563346.618是
00051Fructose and mannose metabolismmet54901.385是
00051Fructose and mannose metabolismgene1249301.449是
00051Fructose and mannose metabolismjoint1783692.997是
00052Galactose metabolismmet48833.066是
00052Galactose metabolismgene874712.771是
00052Galactose metabolismjoint1353295.958是
00053Ascorbate and aldarate metabolismmet51820.7988是
00053Ascorbate and aldarate metabolismgene631500.5695是
00053Ascorbate and aldarate metabolismjoint1141971.511是
00061Fatty acid biosynthesismet56933.536是
00061Fatty acid biosynthesisgene393730.3812是
00061Fatty acid biosynthesisjoint957381.193是
00062Fatty acid elongationmet37502.107是
00062Fatty acid elongationgene25420.9601是
00062Fatty acid elongationjoint621771.153是
00071Fatty acid degradationmet45712.386是
00071Fatty acid degradationgene604220.2767是
00071Fatty acid degradationjoint1056800.9151是
00073Cutin, suberine and wax biosynthesismet20170.03801是
00073Cutin, suberine and wax biosynthesisgene20280.02632是
00073Cutin, suberine and wax biosynthesisjoint40640.1808是
00100Steroid biosynthesismet56600.9684是
00100Steroid biosynthesisgene34681.034是
00100Steroid biosynthesisjoint901372.395是
00130Ubiquinone and other terpenoid-quinone biosynthesismet68720.1936是
00130Ubiquinone and other terpenoid-quinone biosynthesisgene641470.5709是
00130Ubiquinone and other terpenoid-quinone biosynthesisjoint1322081.086是
00220Arginine biosynthesismet22291.345是
00220Arginine biosynthesisgene663670.8712是
00220Arginine biosynthesisjoint881582.299是
00230Purine metabolismmet771161.57是
00230Purine metabolismgene21920561.092是
00230Purine metabolismjoint2967542.819是
00232Caffeine metabolismmet18210.2794是
00232Caffeine metabolismgene16360.2905是
00232Caffeine metabolismjoint34550.8532是
00240Pyrimidine metabolismmet59880.6319是
00240Pyrimidine metabolismgene10911370.7799是
00240Pyrimidine metabolismjoint1684841.912是
00250Alanine, aspartate and glutamate metabolismmet27380.3523是
00250Alanine, aspartate and glutamate metabolismgene704420.9695是
00250Alanine, aspartate and glutamate metabolismjoint971982.465是
00260Glycine, serine and threonine metabolismmet48821.887是
00260Glycine, serine and threonine metabolismgene1148811.757是
00260Glycine, serine and threonine metabolismjoint1623374.026是
00261Monobactam biosynthesismet29260.1336是
00261Monobactam biosynthesisgene27180.08923是
00261Monobactam biosynthesisjoint56670.3084是
00270Cysteine and methionine metabolismmet641012.15是
00270Cysteine and methionine metabolismgene1318942.036是
00270Cysteine and methionine metabolismjoint1954394.522是
00280Valine, leucine and isoleucine degradationmet39641.557是
00280Valine, leucine and isoleucine degradationgene713400.8128是
00280Valine, leucine and isoleucine degradationjoint1103052.342是
00290Valine, leucine and isoleucine biosynthesismet22300.5357是
00290Valine, leucine and isoleucine biosynthesisgene19642.092是
00290Valine, leucine and isoleucine biosynthesisjoint411024.695是
00300Lysine biosynthesismet33481.138是
00300Lysine biosynthesisgene481340.9681是
00300Lysine biosynthesisjoint811572.309是
00310Lysine degradationmet51660.3882是
00310Lysine degradationgene9911000.1978是
00310Lysine degradationjoint1503520.6244是
00330Arginine and proline metabolismmet69970.7452是
00330Arginine and proline metabolismgene1145462.587是
00330Arginine and proline metabolismjoint1833135.629是
00340Histidine metabolismmet35401.41是
00340Histidine metabolismgene501111.105是
00340Histidine metabolismjoint851302.28是
00350Tyrosine metabolismmet61790.424是
00350Tyrosine metabolismgene856290.6364是
00350Tyrosine metabolismjoint1463111.519是
00360Phenylalanine metabolismmet43550.6893是
00360Phenylalanine metabolismgene755750.6464是
00360Phenylalanine metabolismjoint1182321.567是
00380Tryptophan metabolismmet52560.1482是
00380Tryptophan metabolismgene762360.5694是
00380Tryptophan metabolismjoint1282111.385是
00400Phenylalanine, tyrosine and tryptophan biosynthesismet34512.398是
00400Phenylalanine, tyrosine and tryptophan biosynthesisgene748331.071是
00400Phenylalanine, tyrosine and tryptophan biosynthesisjoint1083682.565是
00402Benzoxazinoid biosynthesismet981.5是
00402Benzoxazinoid biosynthesisgene871.333是
00402Benzoxazinoid biosynthesisjoint17162.833是
00410beta-Alanine metabolismmet24351.194是
00410beta-Alanine metabolismgene463151.122是
00410beta-Alanine metabolismjoint701542.714是
00430Taurine and hypotaurine metabolismmet21300.9842是
00430Taurine and hypotaurine metabolismgene29840.6839是
00430Taurine and hypotaurine metabolismjoint50781.903是
00440Phosphonate and phosphinate metabolismmet45440.2807是
00440Phosphonate and phosphinate metabolismgene48700.2414是
00440Phosphonate and phosphinate metabolismjoint931140.647是
00450Selenocompound metabolismmet21220.09737是
00450Selenocompound metabolismgene36560.07227是
00450Selenocompound metabolismjoint57880.2744是
00460Cyanoamino acid metabolismmet44450.2763是
00460Cyanoamino acid metabolismgene371020.504是
00460Cyanoamino acid metabolismjoint811421.083是
00470D-Amino acid metabolismmet60740.05815是
00470D-Amino acid metabolismgene561620.564是
00470D-Amino acid metabolismjoint1162321.378是
00480Glutathione metabolismmet35501.007是
00480Glutathione metabolismgene554191.176是
00480Glutathione metabolismjoint902092.804是
00500Starch and sucrose metabolismmet35852.368是
00500Starch and sucrose metabolismgene1099362.218是
00500Starch and sucrose metabolismjoint1443315.155是
00510N-Glycan biosynthesismet1090.5139是
00510N-Glycan biosynthesisgene21250.2是
00510N-Glycan biosynthesisjoint31460.7138是
00520Amino sugar and nucleotide sugar metabolismmet721071.447是
00520Amino sugar and nucleotide sugar metabolismgene1196251.774是
00520Amino sugar and nucleotide sugar metabolismjoint1913933.766是
00531Glycosaminoglycan degradationmet100否
00531Glycosaminoglycan degradationgene200否
00531Glycosaminoglycan degradationjoint341是
00540Lipopolysaccharide biosynthesismet42510.5726是
00540Lipopolysaccharide biosynthesisgene26381.213是
00540Lipopolysaccharide biosynthesisjoint68862.196是
00541Biosynthesis of various nucleotide sugarsmet1211340.06681是
00541Biosynthesis of various nucleotide sugarsgene1352830.1374是
00541Biosynthesis of various nucleotide sugarsjoint2563500.3299是
00561Glycerolipid metabolismmet32471.004是
00561Glycerolipid metabolismgene10113541.205是
00561Glycerolipid metabolismjoint1333072.767是
00562Inositol phosphate metabolismmet47702.278是
00562Inositol phosphate metabolismgene793712.299是
00562Inositol phosphate metabolismjoint1262275.151是
00563Glycosylphosphatidylinositol (GPI)-anchor biosynthesismet16120.07143是
00563Glycosylphosphatidylinositol (GPI)-anchor biosynthesisgene1880.01471是
00563Glycosylphosphatidylinositol (GPI)-anchor biosynthesisjoint34320.1723是
00564Glycerophospholipid metabolismmet52842.373是
00564Glycerophospholipid metabolismgene12010162.228是
00564Glycerophospholipid metabolismjoint1724074.94是
00565Ether lipid metabolismmet21220.2是
00565Ether lipid metabolismgene311480.4897是
00565Ether lipid metabolismjoint52941.209是
00566Sulfoquinovose metabolismmet39491.01是
00566Sulfoquinovose metabolismgene50930.8516是
00566Sulfoquinovose metabolismjoint891282.016是
00590Arachidonic acid metabolismmet46480.09394是
00590Arachidonic acid metabolismgene512210.1135是
00590Arachidonic acid metabolismjoint971790.3684是
00591Linoleic acid metabolismmet13120.1136是
00591Linoleic acid metabolismgene251280否
00591Linoleic acid metabolismjoint38630.277是
00592alpha-Linolenic acid metabolismmet51480.05918是
00592alpha-Linolenic acid metabolismgene34480.2282是
00592alpha-Linolenic acid metabolismjoint851040.393是
00600Sphingolipid metabolismmet34511.041是
00600Sphingolipid metabolismgene564001.466是
00600Sphingolipid metabolismjoint901883.46是
00620Pyruvate metabolismmet28550.7179是
00620Pyruvate metabolismgene14124040.5977是
00620Pyruvate metabolismjoint1694031.625是
00630Glyoxylate and dicarboxylate metabolismmet55882.091是
00630Glyoxylate and dicarboxylate metabolismgene1208590.9992是
00630Glyoxylate and dicarboxylate metabolismjoint1753432.827是
00640Propanoate metabolismmet37692.188是
00640Propanoate metabolismgene10211991.515是
00640Propanoate metabolismjoint1393393.953是
00650Butanoate metabolismmet43761.382是
00650Butanoate metabolismgene1158201.45是
00650Butanoate metabolismjoint1583873.122是
00660C5-Branched dibasic acid metabolismmet22300.5167是
00660C5-Branched dibasic acid metabolismgene30950.4433是
00660C5-Branched dibasic acid metabolismjoint521061.05是
00670One carbon pool by folatemet25651.46是
00670One carbon pool by folategene6514600.755是
00670One carbon pool by folatejoint902752.474是
00710Carbon fixation by Calvin cyclemet19341.467是
00710Carbon fixation by Calvin cyclegene371241.178是
00710Carbon fixation by Calvin cyclejoint561052.811是
00730Thiamine metabolismmet28331.262是
00730Thiamine metabolismgene361700.9118是
00730Thiamine metabolismjoint641132.236是
00740Riboflavin metabolismmet18170.2978是
00740Riboflavin metabolismgene532120.1802是
00740Riboflavin metabolismjoint711030.7029是
00750Vitamin B6 metabolismmet23330.8571是
00750Vitamin B6 metabolismgene261140.5683是
00750Vitamin B6 metabolismjoint49981.585是
00760Nicotinate and nicotinamide metabolismmet51570.2522是
00760Nicotinate and nicotinamide metabolismgene976180.3735是
00760Nicotinate and nicotinamide metabolismjoint1482600.9098是
00770Pantothenate and CoA biosynthesismet26320.605是
00770Pantothenate and CoA biosynthesisgene471530.6541是
00770Pantothenate and CoA biosynthesisjoint731421.421是
00780Biotin metabolismmet24261.494是
00780Biotin metabolismgene24451.01是
00780Biotin metabolismjoint48712.362是
00785Lipoic acid metabolismmet29501.328是
00785Lipoic acid metabolismgene251210.7627是
00785Lipoic acid metabolismjoint541192.017是
00790Folate biosynthesismet56660.2061是
00790Folate biosynthesisgene844350.2846是
00790Folate biosynthesisjoint1402860.6811是
00860Porphyrin metabolismmet1161290.8376是
00860Porphyrin metabolismgene1404500.7387是
00860Porphyrin metabolismjoint2563931.551是
00900Terpenoid backbone biosynthesismet44601.149是
00900Terpenoid backbone biosynthesisgene642170.82是
00900Terpenoid backbone biosynthesisjoint1081692.076是
00901Indole alkaloid biosynthesismet80710.08423是
00901Indole alkaloid biosynthesisgene57510.09188是
00901Indole alkaloid biosynthesisjoint1371430.2139是
00902Monoterpenoid biosynthesismet48480.1721是
00902Monoterpenoid biosynthesisgene44400.07863是
00902Monoterpenoid biosynthesisjoint921120.2527是
00904Diterpenoid biosynthesismet1041030.2621是
00904Diterpenoid biosynthesisgene761760.1207是
00904Diterpenoid biosynthesisjoint1802570.3257是
00905Brassinosteroid biosynthesismet26290.2783是
00905Brassinosteroid biosynthesisgene12481.136是
00905Brassinosteroid biosynthesisjoint38982.251是
00906Carotenoid biosynthesismet1091160.4012是
00906Carotenoid biosynthesisgene612100.4842是
00906Carotenoid biosynthesisjoint1702941.062是
00908Zeatin biosynthesismet22200.007143是
00908Zeatin biosynthesisgene1010否
00908Zeatin biosynthesisjoint32340.04731是
00909Sesquiterpenoid and triterpenoid biosynthesismet84840.02512是
00909Sesquiterpenoid and triterpenoid biosynthesisgene75380.004813是
00909Sesquiterpenoid and triterpenoid biosynthesisjoint1591800.04076是
00910Nitrogen metabolismmet17150.1083是
00910Nitrogen metabolismgene663000.137是
00910Nitrogen metabolismjoint831130.4032是
00920Sulfur metabolismmet39640.6437是
00920Sulfur metabolismgene12117451.054是
00920Sulfur metabolismjoint1603452.371是
00940Phenylpropanoid biosynthesismet54670.9528是
00940Phenylpropanoid biosynthesisgene31750.8437是
00940Phenylpropanoid biosynthesisjoint851642.314是
00941Flavonoid biosynthesismet68740.1621是
00941Flavonoid biosynthesisgene27560.4508是
00941Flavonoid biosynthesisjoint951611.193是
00942Anthocyanin biosynthesismet41360.04231是
00942Anthocyanin biosynthesisgene15180.07692是
00942Anthocyanin biosynthesisjoint56780.3357是
00943Isoflavonoid biosynthesismet49430.1188是
00943Isoflavonoid biosynthesisgene18180.3676是
00943Isoflavonoid biosynthesisjoint67910.8855是
00944Flavone and flavonol biosynthesismet30240.03695是
00944Flavone and flavonol biosynthesisgene15150.04945是
00944Flavone and flavonol biosynthesisjoint45520.2119是
00945Stilbenoid, diarylheptanoid and gingerol biosynthesismet19210.6176是
00945Stilbenoid, diarylheptanoid and gingerol biosynthesisgene13140.2576是
00945Stilbenoid, diarylheptanoid and gingerol biosynthesisjoint32411.071是
00950Isoquinoline alkaloid biosynthesismet95920.4244是
00950Isoquinoline alkaloid biosynthesisgene691180.696是
00950Isoquinoline alkaloid biosynthesisjoint1642241.258是
00960Tropane, piperidine and pyridine alkaloid biosynthesismet42330.07805是
00960Tropane, piperidine and pyridine alkaloid biosynthesisgene40480.226是
00960Tropane, piperidine and pyridine alkaloid biosynthesisjoint821130.3193是
00966Glucosinolate metabolismmet69670.4941是
00966Glucosinolate metabolismgene35511.843是
00966Glucosinolate metabolismjoint1041663.571是
00970Aminoacyl-tRNA biosynthesismet52350.002745是
00970Aminoacyl-tRNA biosynthesisgene44140.000554是
00970Aminoacyl-tRNA biosynthesisjoint961010.01512是
00996Biosynthesis of various alkaloidsmet27190.04308是
00996Biosynthesis of various alkaloidsgene1480.02564是
00996Biosynthesis of various alkaloidsjoint41370.1147是
00999Biosynthesis of various plant secondary metabolitesmet111940.07431是
00999Biosynthesis of various plant secondary metabolitesgene74580.1109是
00999Biosynthesis of various plant secondary metabolitesjoint1852050.2229是
01040Biosynthesis of unsaturated fatty acidsmet36240.009244是
01040Biosynthesis of unsaturated fatty acidsgene940否
01040Biosynthesis of unsaturated fatty acidsjoint45720.3277是
01310Nitrogen cyclemet780.7333是
01310Nitrogen cyclegene392250.4339是
01310Nitrogen cyclejoint46761.258是
01320Sulfur cyclemet14190.3333是
01320Sulfur cyclegene442450.5975是
01320Sulfur cyclejoint581231.399是

全部比较的影响值 节点中心性 网络边

各比较结果

7 结果描述

网络规模。96 条纳入通路有 KGML 反应信息;影响值可计算的通路:代谢物网络 95 条、酶网络 92 条、联合网络 96 条。

显著通路。45 个比较累计 FDR<0.05 的“比较 × 通路”:酶网络 20 个、联合网络 11 个、代谢物网络 2 个。代谢物网络命中节点少,有命中节点的通路数中位数只有 18 条(酶网络为 81 条)。

反复出现的通路(P<0.05 的比较数)。酶网络:Phenylpropanoid biosynthesis(32 个比较)、Starch and sucrose metabolism(25 个比较)、Flavonoid biosynthesis(23 个比较);联合网络:Glycolysis / Gluconeogenesis(29 个比较)、Carbon fixation by Calvin cycle(20 个比较)、Starch and sucrose metabolism(17 个比较);代谢物网络:Flavonoid biosynthesis(9 个比较)、C5-Branched dibasic acid metabolism(6 个比较)、Biosynthesis of various alkaloids(4 个比较)。

类黄酮生物合成。酶网络上影响值最高为 0.88(R1_vs_Y1,FDR=0.008);同一通路在代谢物网络上最高为 0.16,联合网络最高为 0.44。

8 生物学意义

数据支持的观察

苯丙烷和类黄酮生物合成在酶网络上反复出现,且类黄酮合成的命中酶占据了通路网络中的关键位置(影响值接近 0.9),与联合富集、WGCNA 和关键通路排序的结论一致 [24]。糖酵解、卡尔文循环、淀粉和蔗糖代谢在联合网络上反复出现,说明碳代谢主干上的酶和中间产物同时发生变化。

需要进一步验证的假设

处理和水平可能改变了碳代谢主干和苯丙烷—类黄酮分支之间的物质分配。影响值只反映差异分子在网络中的位置,不反映通量;需要用关键酶活性、代谢物定量或同位素示踪验证。代谢物网络的命中节点很少,代谢层的拓扑结论不可靠。

9 局限性

KEGG 参考通路是多物种合并的通用图,不保证本物种中每个酶和反应都存在;物种确认后可改用物种专属通路重算。代谢物只有约三分之一有 KEGG 编号,代谢物层的命中节点很少,影响值和 P 值波动大。介数中心性只反映网络位置,不反映通量大小或限速步骤。同一 KO 下的多个基因、同一化合物下的多个代谢物被合并为一个节点,节点内方向相反的变化会被掩盖。三种网络的节点和背景不同,影响值不能跨层直接比较大小,只能看各自的排序和一致性。

参考文献

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