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GhMYB43负调控木质素的生物合成和茉莉酸信号
沈吉丽,肖胜华,惠慧,努日曼古丽·艾尼,胡琴,张晓君,杨兆光,聂新辉,朱龙付
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GhMYB43负调控木质素的生物合成和茉莉酸信号
GhMYB43 Negatively Regulates Lignin Biosynthesis and Jasmonic Acid Signaling
【目的】棉花黄萎病是由土壤传播的植物维管束真菌病害,导致每年棉花产量和品质的严重损失。本研究通过鉴定抗病基因,研究抗病机制,为棉花多抗种质资源创新提供理论基础。【方法】利用酵母单杂交（Yeast one hybrid）筛选到1个GhLac1上游的调节因子,并通过构建系统进化树、氨基酸序列多重比对、定量逆转录聚合酶链反应（Reverse transcription-quantitative polymerase chain reaction, RT-qPCR）、烟草瞬时转化、双荧光素酶检测系统、病毒诱导的基因沉默技术、棉花遗传转化技术等对该转录因子相关功能进行验证。【结果】Gh_D12G0544与拟南芥（Arabidopsis thaliana）中AtMYB43同源性最高,将其编码基因命名为GhMYB43。GhMYB43位于陆地棉Dt亚组第12号染色体上,编码1个含376个氨基酸的蛋白质,含有2个MYB结构域;RT-qPCR分析发现GhMYB43在茎中优势转录,受水杨酸和过氧化氢诱导上调表达,而受茉莉酸甲酯诱导下调表达,转录水平会受大丽轮枝菌（Verticilium dahliae）诱导;亚细胞定位结果显示,GhMYB43蛋白定位于细胞核中;双荧光素酶检测系统验证该基因具有转录激活活性;抗病性鉴定发现抑制GhMYB43转录会增强棉花植株对黄萎病菌的抗性;超表达GhMYB43增强了棉花对黄萎病菌的敏感性;木质素组织化学染色和含量测定结果表明,超表达GhMYB43转基因系的木质素含量明显低于对照材料。RT-qPCR分析表明,GhMYB43负调控木质素合成途径中关键酶基因的转录水平,并且负调控茉莉酸信号路径相关基因的转录。【结论】GhMYB43负调控木质素合成和茉莉酸信号。
[Objective] Verticillium wilt is a vascular fungal disease spread by soil, which causes serious loss of cotton yield and reduction in quality every year. This study provides a theoretical basis for the innovation of cotton multi-resistant germplasms by identifying disease resistance genes and studying disease resistance mechanisms. [Method] Yeast one hybrid was performed to screen the upstream regulatory factors of GhLac1, and the construction of phylogenetic trees, multiple alignment of amino acid sequences, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), transient tobacco transformation, dual luciferase assay system, virus-induced gene silencing and cotton genetic transformation technology were performed to verify the function of this transcription factor. [Result] Gh_D12G0544 is the most homologous to AtMYB43 in Arabidopsis thaliana, so its encoding gene was named GhMYB43. GhMYB43 is located on chromosome 12 of the Dt subgroup of upland cotton and encodes a protein containing 376 amino acids that contains two MYB domains. RT-qPCR analysis showed that GhMYB43 was predominantly transcribed in the stem and was up-regulated by salicylic acid (SA) and H2O2, but down-regulated by methyl jasmonate (Me-JA); at the same time, the transcription level was induced by Verticillium dahliae. Subcellular localization results showed that GhMYB43 protein is localized in the nucleus. The dual luciferase assay system verified that the gene has transcriptional activation activity. Disease resistance identification found that the inhibition GhMYB43 transcription level enhanced the resistance of cotton to V. dahliae, and overexpression of GhMYB43 increased the susceptibility of plants to this pathogen. Histochemical staining and content determination of lignin showed that the lignin content of GhMYB43 overexpressing transgenic lines was significantly lower than that of control materials. RT-qPCR analysis showed that GhMYB43 negatively regulates the transcription level of enzyme genes involved in the lignin synthesis and JA signaling pathway. [Conclusion] GhMYB43 negatively regulates lignin synthesis and JA signal.
棉花黄萎病 / GhMYB43 / 抗病性 / 木质素 / 茉莉酸信号 {{custom_keyword}} /
cotton Verticillium wilt / GhMYB43 / disease resistance / lignin / jasmonic acid signal {{custom_keyword}} /
表1 RT-qPCR引物序列Table 1 RT-qPCR primers used in this study |
| 基因名称 Gene name | 正向引物 Forward primer | 反向引物 Reverse primer |
| GhUB7 | GAAGGCATTCCACCTGACCAAC | CTTGACCTTCTTCTTCTTGTGCTTG |
| GhHCT-1 | CTGAAAGCACAGCAATCTCCAT | CCAAAGTAACCAGGTGGGAGTG |
| GhCCoAOMT-1 | TGGTGAAGGTTGGTGGTTTGAT | CATGCAAATCTCAATCCTGGGG |
| GhCCoAOMT-3 | GAGACCAGTGTGTATCCGAGGG | CAAGGGCAGTGGCTAAGAGAGA |
| GhCOMT-2 | TTGAAAGATGCTGTGCTGGATG | CCTTGGAAACCATCATATGTATCG |
| GhLOX4-1 | ATGGCTCCAAAGAGAAGCAAAG | CGTAAAAGGGACGTTAAGAACC |
| GhLOX6-1 | AATTCGGGGAAGAGCGTTGAGG | ACCGAAGTCGGATGGGACAGTA |
| GhAOS1 | CGGATTAGAGCCTCAGTGTCGG | CGGATTAGAGCCTCAGTGTCGG |
| GhAOC3 | AGGGGAGATTTGGAGAAACGG | TCAAAAATGCCAGACCCACCAG |
图1 GhMYB43的基因克隆和结构分析a：使用棉花和拟南芥酵母转录因子文库筛选可与GhLac1启动子结合的转录因子;AD：激活域;BD：结合域;3-AT：3-氨基-1,2,4-三唑。b：GhMYB43基因结构示意图。Fig. 1 Gene cloning and structure analysis of GhMYB43 a: using cotton and Arabidopsis yeast transcription factor libraries to screen the transcription factors that can be bound to the GhLac1 promoter; AD: activation domain; BD: binding domain; 3-AT: 3-amino-1,2,4-triazole. b: structure of GhMYB43. |
图2 GhMYB43同源蛋白序列系统进化树和同源蛋白质多重序列比对方框表示R2R3结构域。GhMYB43：陆地棉Gossypium hirsutum,AT5G16600;AtMYB43：拟南芥Arabidopsis thaliana,AT5G16600; AtMYB85：拟南芥Arabidopsis thaliana,AT4G22680;CsMYB20：甜橙Citrus sinensis,XP_006482113.1;DzODORANT1：榴莲Durio zibethinus,XP_022728015.1;GrODORANT1：雷蒙德氏棉Gossypium raimondii,XP_012436774.1;HuODORANT1：哥伦比亚锦葵Herrania umbratica,XP_021296684.1;PeODORANT1：胡杨Populus euphratica,XP_011007235.1;TcMYB20：可可树Theobroma cacao,EOY03898.1;ZjMYB20：金丝小枣Ziziphus jujuba,XP_015901922.1。Fig. 2 Phylogenetic tree and multiple sequence alignment homologous proteins of GhMYB43 The box shows the R2R3 domain. |
图3 GhMYB43组织诱导转录和诱导转录模式分析a：GhMYB43的组织转录模式;b、c、d、e分别为GhMYB43在根中受水杨酸（SA）、H2O2、茉莉酸甲酯（Me-JA）和大丽轮枝菌V991诱导的转录模式。所提取组织材料均来源于陆地棉YZ1,内参基因为GhUB7。Mock为水处理。数据为平均值±标准差,基于3次生物学重复。组间数据采用t检验进行差异显著性分析,不同小写字母表示差异显著（P<0.05）。Fig. 3 Tissue expression patterns and induced expression patterns of GhMYB43 analyzed by RT-qPCR a: tissue expression pattern of GhMYB43. b, c, d, e: SA, H2O2, Me-JA, V991 induced expression patterns of GhMYB43 in roots. GhMYB43 was extracted from different tissues of the cotton line YZ1. GhUB7 is the internal reference gene. Mock is water treatment. The values are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at the 0.05 probability level (P<0.05). |
图5 GhMYB43 棉花原生质体中的转录激活活性的分析a：棉花原生质体双荧光素酶检测系统示意图;GAL4为啤酒酵母的半乳糖苷酶基因激活因子,DB为DNA结合域。 b：GAL4DB-GhMYB43的转录激活活性。LUC为萤火虫荧光素酶,REN为海参荧光素酶。数据为平均值±标准差,基于3次生物学重复。组间数据采用t检验进行差异显著性分析,**表示差异极显著（P<0.01）。Fig. 5 Transcriptional activity assay of GhMYB43 in cotton protoplasts a: schematic diagram of double luciferase activity detection system of cotton protoplast. GAL4: an activator of galactosidase gene in Saccharomyces cerevisiae; DB: DNA binding domain. b: GAL4DB-GhMYB43 transcription activity using relative activity of luciferase. LUC: firefly luciferase; REN: Renilla luciferase. The values are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at the 0.01 probability level (P<0.01). |
图6 超表达GhMYB43抑制了转基因材料对黄萎病菌的抗性a：超表达GhMYB43株系拷贝数分析。b：转基因和野生型（WT）材料中GhMYB43的转录水平。GhUB7为内参基因。c：野生型（WT）植株和超表达材料OE-8、OE-77、OE-81接种黄萎病菌后15 d的表型。d：WT植株和超表达材料OE-8、OE-77、OE-81接种黄萎病菌后15 d病情指数和发病率统计。e：WT植株和超表达材料OE-8、OE-77、OE-81接种黄萎病菌后15 d剖秆鉴定结果。f：WT植株和超表达材料OE-8、OE-77、OE-81接种黄萎病菌后15 d病原菌恢复培养。分图b、d中数据为平均值±标准差（n=3）。组间数据采用t检验进行差异显著性分析,不同小写字母表示差异显著（P<0.05）。Fig. 6 Overexpressing of GhMYB43 impair cotton resistance to Verticillium dahliae a: southern blotting analysis of the selected transgenic lines of GhMYB43.b: analysis of GhMYB43 expression levels of GhMYB43 transgenic lines and wild type (WT). GhUB7 was used as control. c: disease symptoms in WT and over-expression lines plants after inoculation with V. dahliae strain V991 for 15 d. d: the disease rate and disease index of over-expression lines plants after inoculation with V. dahliae strain V991 for 15 d. e: the stem cutting phenotype of WT and over-expression lines plants after inoculation for 15 d. f: stem sections were cultured on the medium after inoculated with V. dahliae for 15 d, as a measure for fungal colonization. The values in figures b and d are the means±standard deviation(n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at the 0.05 probability level (P<0.05). |
图7 VIGS抑制棉花GhMYB43的表达情况及其对黄萎病菌的抗性鉴定结果a：CLA基因沉默后植株的白化表型。b：GhMYB43的干涉情况检测。c：VIGS抑制GhMYB43表达植株与对照的表型。d：VIGS抑制GhMYB43表达的植株接种V991后12~18 d的发病率和病情指数。e：剖秆鉴定结果。f：病原菌恢复培养17 d时的结果。分图b、d中的数据为平均值±标准差（n=3）。组间数据采用t检验进行差异显著性分析,不同小写字母表示差异显著（P<0.05）。Fig. 7 VIGS inhibition of the expression of GhMYB43 in cotton and its resistance to Verticillium dahliae a: the whitening phenotype appeared in the plants after CLA was silenced. b: analysis of the expression of GhMYB43 in TRV∷00 and TRV∷GhMYB43. c: phenotype of GhMYB43 silenced plants compared to control. d: the disease rate and disease index of GhMYB43 silenced plants at 12-18 d after inoculation with V.dahliae. e: the stem cutting phenotype of TRV∷00 and TRV∷GhMYB43. f: stem sections were cultured on the medium after inoculation with V. dahliae for 17 d, as a measure for fungal colonization. The values in figures b and d are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at 0.05 probability level (P<0.05). |
图8 超表达GhMYB43棉花的木质素含量情况a：间苯三酚染色显示木质素棉花茎秆中的沉积情况。b：对照材料（WT）和转GhMYB43基因材料茎秆中木质素含量。Mock：水处理;WT：野生型。数据为平均值±标准差,基于3次生物学重复。组间数据采用t检验进行差异显著性分析,*、**分别表示差异显著（P<0.05）、极显著（P<0.01）。Fig. 8 Lignin content of cotton overexpressing GhMYB43 a: pyrogallol staining shows deposition of lignin in cotton stems. b: lignin content in stems of control materials(WT) and GhMYB43 transgenic materials. Mock: water treatment; WT: wild type plants. The values are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; *, ** indicate significance at the 0.05 (P<0.05), 0.01 (P<0.01) probability level, respectively. |
图9 GhMYB43负调控木质素合成相关基因的表达a：水处理下超表达GhMYB43株系和野生型（WT）中木质素合成相关基因的转录水平;b：V991处理后超表达GhMYB43株系中木质素合成相关基因的转录水平;c：水处理下VIGS抑制GhMYB43表达植株中木质素合成相关基因的转录水平;d：V991处理后VIGS抑制GhMYB43表达植株中木质素合成相关基因的转录水平。数据为平均值±标准差（n=3）。组间数据采用t检验进行差异显著性分析,不同小写字母表示差异显著（P<0.05）。Fig. 9 GhMYB43 negatively regulates the expression level of genes involved in lignin synthesis a: expression of lignin synthesis-related genes in wild type (WT) and GhMYB43-overexpressing lines inoculated with water. b: expression lignin synthesis-related genes in WT and GhMYB43-overexpressing lines inoculated with Verticillium dahliae. c: expression of lignin synthesis-related genes in TRV∷00, TRV∷GhMYB43 seedlings of cotton inoculated with water. d: expression of lignin synthesis-related genes in TRV∷00, TRV∷GhMYB43 seedlings of cotton inoculated with V. dahliae. The values are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at the 0.05 probability level (P<0.05). |
图10 GhMYB43负调控JA激素合成相关基因的表达a：水处理（Mock）和V991处理后,GhMYB43过表达株系和野生型（WT）植株中茉莉酸（JA）合成相关基因的表达。b：Mock处理和V991处理后,TRV∷00和TRV∷GhMYB43中JA合成相关基因的表达。内参基因为GhUB7。数据为平均值±标准差（n=3）。组间数据采用t检验进行差异显著性分析,不同小写字母表示差异显著（P<0.05）。Fig. 10 GhMYB43 negatively regulates the expression level of genes involved in JA synthesis a: expression of jasmonate (JA) pathway genes in roots of GhMYB43-overexpressing lines and wild type (WT) plants infected with water (Mock) and V991. b: expression of JA pathway genes in roots of TRV∷GhMYB43 and TRV∷00 seedlings of cotton infected with Mock and V991. The values in figures b and d are the means ± standard deviation (n=3). Statistical analyses were performed using Student's t test; different lowercases indicate significance at the 0.05 probability level (P<0.05). |
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Verticillium dahliae is a phytopathogenic fungal pathogen that causes vascular wilt diseases responsible for considerable decreases in cotton yields. The lignification of cell wall appositions is a conserved basal defence mechanism in the plant innate immune response. However, the function of laccase in defence-induced lignification has not been described. Screening of an SSH library of a resistant cotton cultivar, Jimian20, inoculated with V. dahliae revealed a laccase gene that was strongly induced by the pathogen. This gene was phylogenetically related to AtLAC15 and contained domains conserved by laccases; therefore, we named it GhLAC15. Quantitative reverse transcription-polymerase chain reaction indicated that GhLAC15 maintained higher expression levels in tolerant than in susceptible cultivars. Overexpression of GhLAC15 enhanced cell wall lignification, resulting in increased total lignin, G monolignol and G/S ratio, which significantly improved the Verticillium wilt resistance of transgenic Arabidopsis. In addition, the levels of arabinose and xylose were higher in transgenic plants than in wild-type plants, which resulted in transgenic Arabidopsis plants being less easily hydrolysed. Furthermore, suppression of the transcriptional level of GhLAC15 resulted in an increase in susceptibility in cotton. The content of monolignol and the G/S ratio were lower in silenced cotton plants, which led to resistant cotton cv. Jimian20 becoming susceptible. These results demonstrate that GhLAC15 enhances Verticillium wilt resistance via an increase in defence-induced lignification and arabinose and xylose accumulation in the cell wall of Gossypium hirsutum. This study broadens our knowledge of defence-induced lignification and cell wall modifications as defence mechanisms against V. dahliae.© 2018 The Authors. Molecular Plant Pathology published by BSPP and John Wiley & Sons Ltd.
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Secondary cell wall (SCW) biosynthesis during wood formation in trees is controlled by a multilevel regulatory network that coordinates the expression of substantial genes. However, few transcription factors involved in the negative regulation of secondary wall biosynthesis have been characterized in tree species. In this study, we isolated an R2R3 MYB transcription factor MYB189 from Populus trichocarpa, which is expressed predominantly in secondary vascular tissues, especially in the xylem. A novel repression motif was identified in the C-terminal region of MYB189, which indicates this factor was a transcriptional repressor. Overexpression (OE) of MYB189 in Arabidopsis and poplar resulted in a significant reduction in the contents of lignin, cellulose and hemicelluloses. Vascular development in stems of MYB189 OE lines was markedly inhibited, leading to a dramatic decrease in SCW thickness of xylem fibers. Gene expression analyses showed that most of the structural genes involved in the biosynthesis of lignin, cellulose and xylans were significantly downregulated in MYB189-overexpressing poplars compared with the wild-type control. Chromatin immunoprecipitation-quantitative real-time polymerase chain reaction and transient expression assays revealed that MYB189 could directly bind to the promoters of secondary wall biosynthetic genes to repress their expression. Together, these data suggest that MYB189 acts as a repressor to regulate SCW biosynthesis in poplar.© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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The function of the plant hormone jasmonic acid (JA) in the development of tomato () flowers was analyzed with a mutant defective in JA perception (, ). In contrast with Arabidopsis () JA-insensitive plants, which are male sterile, the tomato mutant is female sterile, with major defects in female development. To identify putative JA-dependent regulatory components, we performed transcriptomics on ovules from flowers at three developmental stages from wild type and mutants. One of the strongly downregulated genes in encodes the MYB transcription factor SlMYB21. Its Arabidopsis ortholog plays a crucial role in JA-regulated stamen development. SlMYB21 was shown here to exhibit transcription factor activity in yeast, to interact with SlJAZ9 in yeast and in planta, and to complement Arabidopsis To analyze SlMYB21 function, we generated clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR associated protein 9 (Cas9) mutants and identified a mutant by Targeting Induced Local Lesions in Genomes (TILLING). These mutants showed female sterility, corroborating a function of MYB21 in tomato ovule development. Transcriptomics analysis of wild type,, and carpels revealed processes that might be controlled by SlMYB21. The data suggest positive regulation of JA biosynthesis by SlMYB21, but negative regulation of auxin and gibberellins. The results demonstrate that SlMYB21 mediates at least partially the action of JA and might control the flower-to-fruit transition.© 2019 American Society of Plant Biologists. All rights reserved.
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The incompatible pathosystem between resistant cotton (Gossypium barbadense cv. 7124) and Verticillium dahliae strain V991 was used to study the cotton transcriptome changes after pathogen inoculation by RNA-Seq. Of 32,774 genes detected by mapping the tags to assembly cotton contigs, 3442 defence-responsive genes were identified. Gene cluster analyses and functional assignments of differentially expressed genes indicated a significant transcriptional complexity. Quantitative real-time PCR (qPCR) was performed on selected genes with different expression levels and functional assignments to demonstrate the utility of RNA-Seq for gene expression profiles during the cotton defence response. Detailed elucidation of responses of leucine-rich repeat receptor-like kinases (LRR-RLKs), phytohormone signalling-related genes, and transcription factors described the interplay of signals that allowed the plant to fine-tune defence responses. On the basis of global gene regulation of phenylpropanoid metabolism-related genes, phenylpropanoid metabolism was deduced to be involved in the cotton defence response. A closer look at the expression of these genes, enzyme activity, and lignin levels revealed differences between resistant and susceptible cotton plants. Both types of plants showed an increased level of expression of lignin synthesis-related genes and increased phenylalanine-ammonia lyase (PAL) and peroxidase (POD) enzyme activity after inoculation with V. dahliae, but the increase was greater and faster in the resistant line. Histochemical analysis of lignin revealed that the resistant cotton not only retains its vascular structure, but also accumulates high levels of lignin. Furthermore, quantitative analysis demonstrated increased lignification and cross-linking of lignin in resistant cotton stems. Overall, a critical role for lignin was believed to contribute to the resistance of cotton to disease.
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Lignin is a phenylpropanoid-derived polymer that functions as a major component of cell walls in plant vascular tissues. Biosynthesis of the aromatic amino acid Phe provides precursors for many secondary metabolites, including lignins and flavonoids. Here, we discovered that MYB transcription factors MYB20, MYB42, MYB43, and MYB85 are transcriptional regulators that directly activate lignin biosynthesis genes and Phe biosynthesis genes during secondary wall formation in Arabidopsis (). Disruption of,,, and resulted in growth development defects and substantial reductions in lignin biosynthesis. In addition, our data showed that these MYB proteins directly activated transcriptional repressors that specifically inhibit flavonoid biosynthesis, which competes with lignin biosynthesis for Phe precursors. Together, our results provide important insights into the molecular framework for the lignin biosynthesis pathway.© 2020 American Society of Plant Biologists. All Rights Reserved.
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Verticillium wilt, caused by Verticillium dahliae Kleb., is a serious threat to cotton (Gossypium spp.) crop production. To enhance our understanding of the plant's complex defensive mechanism, we examined colonization patterns and interactions between V. dahliae and two cotton species, the resistant G. barbadense and the susceptible G. hirsutum. Microscopic examinations and grafting experiments showed that the progression of infection was restricted within G. barbadense. At all pre- and postinoculation sampling times, levels of salicylic acid (SA) were also higher in that species than in G. hirsutum. Comparative RNA-Seq analyses indicated that infection induced dramatic changes in the expression of thousands of genes in G. hirsutum, whereas those changes were fewer and weaker in G. barbadense. Investigations of the morphological and biochemical nature of cell-wall barriers demonstrated that depositions of lignin, phenolic compounds, and callose were significantly higher in G. barbadense. To determine the contribution of a known resistance gene to these processes, we silenced GbEDS1 and found that the transformed plants had decreased SA production, which led to the upregulation of PLASMODESMATA-LOCATED PROTEIN (PDLP) 1 and PDLP6. This was followed by a decline in callose deposition in the plasmodesmata, which then led to increased pathogen susceptibility. This comparison between resistant and susceptible species indicated that both physical and chemical mechanisms play important roles in the defenses of cotton against V. dahliae.
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R2R3-MYB transcription factors are important regulators of the growth and development of plants. Here, CmMYB8 a chrysanthemum gene encoding an R2R3-MYB transcription factor, was isolated and functionally characterized. The gene was transcribed throughout the plant, but most strongly in the stem. When CmMYB8 was over-expressed, a number of genes encoding components of lignin synthesis were down-regulated, and the plants' lignin content was reduced. The composition of the lignin in the transgenic plants was also altered, and its S/G ratio was reduced. A further consequence of the over-expression of CmMYB8 was to lessen the transcript abundance of key genes involved in flavonoid synthesis, resulting in a reduced accumulation of flavonoids. The indication is that the CmMYB8 protein participates in the negative regulation of both lignin and flavonoid synthesis.Copyright © 2020 Elsevier Masson SAS. All rights reserved.
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| [33] |
To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that are a highly effective and inducible defense system. Central to this system are the plant defense hormones jasmonic acid (JA) and salicylic acid (SA) and crosstalk between the two, which may play an important role in defense responses to specific pathogens or even genotypes. Here, we used the - pathosystem to test how the host's defense system functions against genetic variation in a pathogen. We measured defense-related phenotypes and transcriptomic responses in Arabidopsis wild-type Col-0 and JA- and SA-signaling mutants, and, individually challenged with 96 diverse isolates. Those data showed genetic variation in the pathogen influences on all components within the plant defense system at the transcriptional level. We identified four gene coexpression networks and two vectors of defense variation triggered by genetic variation in This showed that the JA and SA signaling pathways functioned to constrain/canalize the range of virulence in the pathogen population, but the underlying transcriptomic response was highly plastic. These data showed that plants utilize major defense hormone pathways to buffer disease resistance, but not the metabolic or transcriptional responses to genetic variation within a pathogen.© 2017 American Society of Plant Biologists. All rights reserved.
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PDF(10806 KB)
表1 RT-qPCR引物序列
图1 GhMYB43的基因克隆和结构分析图2 GhMYB43同源蛋白序列系统进化树和同源蛋白质多重序列比对图3 GhMYB43组织诱导转录和诱导转录模式分析图4 GhMYB43亚细胞定位图5 GhMYB43 棉花原生质体中的转录激活活性的分析图6 超表达GhMYB43抑制了转基因材料对黄萎病菌的抗性图7 VIGS抑制棉花GhMYB43的表达情况及其对黄萎病菌的抗性鉴定结果图8 超表达GhMYB43棉花的木质素含量情况图9 GhMYB43负调控木质素合成相关基因的表达图10 GhMYB43负调控JA激素合成相关基因的表达/
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