共查询到20条相似文献，搜索用时 15 毫秒
1.
2.
Hui Yang Xiaokang Chen Ruixin Yang Jing Cheng Yong Chen Matthieu H. A. J. Joosten Yu Du 《Molecular Plant Pathology》2023,24(5):399-412
Mitogen-activated protein kinase (MAPK) cascades play pivotal roles in plant responses to both biotic and abiotic stress. A screen of a Nicotiana benthamiana cDNA virus-induced gene silencing (VIGS) library for altered plant responses to inoculation with Phytophthora infestans previously identified an NbMKK gene, encoding a clade D MAPKK that we renamed as NbMKK5, which is involved in immunity to P. infestans. To study the role of the potato orthologous gene, referred to as StMKK5, in the response to P. infestans, we transiently overexpressed StMKK5 in N. benthamiana and observed that cell death occurred at 2 days postinfiltration. Silencing of the highly conserved eukaryotic protein SGT1 delayed the StMKK5-induced cell death, whereas silencing of the MAPK-encoding gene NbSIPK completely abolished the cell death response. Further investigations showed that StMKK5 interacts with, and directly phosphorylates, StSIPK. Furthermore, both StMKK5 and StSIPK trigger salicylic acid (SA)- and ethylene (Eth)-related gene expression, and co-expression of the salicylate hydroxylase NahG with the negative regulator of Eth signalling CTR1 hampers StSIPK-triggered cell death. This observation indicates that the cell death triggered by StMKK5-StSIPK is dependent on the combination of SA- and Eth-signalling. By introducing point mutations, we showed that the kinase activity of both StMKK5 and StSIPK is required for triggering cell death. Genetic analysis showed that StMKK5 depends on StSIPK to trigger plant resistance. Thus, our results define a potato StMKK5-SIPK module that positively regulates immunity to P. infestans via activation of both the SA and Eth signalling pathways. 相似文献
3.
MAPK级联途径参与ABA信号转导调节的植物生长发育过程 总被引：2，自引：0，他引：2
植物激素ABA参与调控植物生长发育和生理代谢以及多种胁迫应答过程,促分裂原活化蛋白激酶（MAPK）级联途径应答于多种生物和非生物胁迫,广泛参与调控植物的生长发育。MAPK级联途径与ABA信号转导协同作用参与调控植物种子萌发、气孔运动和生长发育,本文主要归纳了植物中受ABA调控激活的MAPK级联途径成员,阐述了它们参与ABA信号转导调控植物生理反应和生长发育的过程,并对MAPK级联途径与ABA信号转导的研究方向作出了展望,指出对MAPK下游底物的筛选是完善MAPK级联途径的重要组成部分。 相似文献
4.
Effects of actinomycin-D (ACT), cycloheximide (CH), rifampicin (RIF) and chloramphenicol (CAP) on senescence of soybean leaf discs were investigated. All inhibitors tested are effective in retarding senescence of soybean leaf discs. However, CH is more effective than ACT, RIF and CAP, suggesting that activation of preexisting, latent metabolic systems present in the cytoplasm piays predominant role in the initiating of leaf senescence. However, the possibility that events taking place in the nucleus or chloroplast are essential for the initiation of leaf senescence cannot be excluded. 相似文献
5.
The effects of growth temperature and winter duration on the leaf phenology of Erythronium japonicum were examined in two experiments. Bulbs wintered in the field were cultivated at 10 and 20° C and the bulbs were cultivated at 15° C after chilling treatment at 3° C for 60 and 120 days and without chilling in winter. The plants cultivated at 20° C showed significantly earlier leaf emergence, a more rapid rate of leaf extension and shorter leaf longevity than those cultivated at 10° C. The decrease in the leaf longevity at 20° C resulted from the decreases in the durations of all of the developmental, mature, and senescent phases. The bulbs without chilling treatment did not sprout leaves and those with chilling treatment sprouted leaves. The increase in the length of chilling treatment from 60 to 120 days affected leaf phenology in same manner as the increase in the growth temperature from 10 to 20° C. 相似文献
6.
7.
8.
9.
活性氧(ROS)和植物激素是植物衰老过程中重要的内在或者外在的调控因子.我们发现,相对于离体诱导的衰老过程,在脱落酸(ABA)和乙烯(ethylene)促进的衰老过程中有较多的活性氧积累;在对拟南芥磷脂酶Dδ (PLDδ)缺失型突变体的研究中发现,与野生型相比,突变体在衰老过程中产生较少的活性氧.我们比较了上述两种基因型的离体叶片在离体、ABA和ethylene三种衰老处理下内源的ABA、茉莉酸甲酯(MeJA)、玉米素核苷(Zeatin Riboside,ZR)和吲哚乙酸(IAA)的含量变化,发现每一种激素对上述三种衰老处理的响应模式都很相似.在离体诱导的衰老中,两种基因型拟南芥的内源激素含量没有差异;而在ABA促进的衰老过程中,PLDδ缺失型突变体叶片中的MeJA的含量较低,ZR和IAA含量较高;在乙烯促进的衰老过程中,突变体中的ABA和MeJA的含量较低,ZR和IAA含量较高.上述内源激素的这种变化可能有助于延缓突变体的衰老. 相似文献
10.
Morris K MacKerness SA Page T John CF Murphy AM Carr JP Buchanan-Wollaston V 《The Plant journal : for cell and molecular biology》2000,23(5):677-685
Leaf senescence is a complex process that is controlled by multiple developmental and environmental signals and is manifested by induced expression of a large number of different genes. In this paper we describe experiments that show, for the first time, that the salicylic acid (SA)-signalling pathway has a role in the control of gene expression during developmental senescence. Arabidopsis plants defective in the SA-signalling pathway (npr1 and pad4 mutants and NahG transgenic plants) were used to investigate senescence-enhanced gene expression, and a number of genes showed altered expression patterns. Senescence-induced expression of the cysteine protease gene SAG12, for example, was conditional on the presence of SA, together with another unidentified senescence-specific factor. Changes in gene expression patterns were accompanied by a delayed yellowing and reduced necrosis in the mutant plants defective in SA-signalling, suggesting a role for SA in the cell death that occurs at the final stage of senescence. We propose the presence of a minimum of three senescence-enhanced signalling factors in senescing leaves, one of which is SA. We also suggest that a combination of signalling factors is required for the optimum expression of many genes during senescence. 相似文献
11.
12.
We screened for mutants of Arabidopsis thaliana that displayed enhanced disease resistance to the powdery mildew pathogen Erysiphe cichoracearum and identified the edr3 mutant, which formed large gray lesions upon infection with E. cichoracearum and supported very little sporulation. The edr3-mediated disease resistance and cell death phenotypes were dependent on salicylic acid signaling, but independent of ethylene and jasmonic acid signaling. In addition, edr3 plants displayed enhanced susceptibility to the necrotrophic fungal pathogen Botrytis cinerea, but showed normal responses to virulent and avirulent strains of Pseudomonas syringae pv. tomato. The EDR3 gene was isolated by positional cloning and found to encode Arabidopsis dynamin-related protein 1E (DRP1E). The edr3 mutation caused an amino acid substitution in the GTPase domain of DRP1E (proline 77 to leucine) that is predicted to block GTP hydrolysis, but not GTP binding. A T-DNA insertion allele in DRP1E did not cause powdery mildew-induced lesions, suggesting that this phenotype is caused by DRP1E being locked in the GTP-bound state, rather than by a loss of DRP1E activity. Analysis of DRP1E-green fluorescent protein fusion proteins revealed that DRP1E is at least partially localized to mitochondria. These observations suggest a mechanistic link between salicylic acid signaling, mitochondria and programmed cell death in plants. 相似文献
13.
14.
Tang D Ade J Frye CA Innes RW 《The Plant journal : for cell and molecular biology》2005,44(2):245-257
We have identified an Arabidopsis mutant that displays enhanced disease resistance (edr2) to the biotrophic powdery mildew pathogen Erysiphe cichoracearum. Inhibition of fungal growth on edr2 mutant leaves occurred at a late stage of the infection process and coincided with formation of necrotic lesions approximately 5 days after inoculation. Double-mutant analysis revealed that edr2-mediated resistance is suppressed by mutations that inhibit salicylic acid (SA)-induced defense signaling, including npr1, pad4 and sid2, demonstrating that edr2-mediated disease resistance is dependent on SA. However, edr2 showed normal responses to the bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000. EDR2 appears to be constitutively transcribed in all tissues and organs and encodes a novel protein, consisting of a putative pleckstrin homology (PH) domain and a steroidogenic acute regulatory protein-related lipid-transfer (START) domain, and contains an N-terminal mitochondrial targeting sequence. The PH and START domains are implicated in lipid binding, suggesting that EDR2 may provide a link between lipid signaling and activation of programmed cell death mediated by mitochondria. 相似文献
15.
当绿豆幼苗在自然条件下生长到12d龄时,剪下第一对叶片,漂浮在水面,以蓝光荧光灯照射叶片,用白光和黑暗为对照。蓝光处理可延缓叶片叶绿素和蛋白质含量的降低,促进气孔的开放,维持SOD活性在较高的水平,从而延缓了质膜相对透性的增大。因此,我们认为,蓝光可以延缓绿豆幼苗离体叶片的衰老。 相似文献
16.
17.
MAPK级联途径在真核生物细胞的信号传递过程中起着重要的作用.MAPK级联途径由MAPK、MAPKK和MAPKKK三类酶蛋白组成.这三类蛋白质的结构非常保守,通过磷酸化作用传递各种信号.在酵母和动、植物细胞中已经发现了一系列的MAPK级联途径成员,使真核生物的信号传递途径逐渐得到阐明. 相似文献
18.
Treatment of triadimefon on detached leaves of mung bean (Phaseolus radiatus L. ) seedlings increased the levels of chlorophyll and soluble proteins. Declined activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate-peroxidase (AsA-POD) and contents of ascorbate (ASA) and glutathione (GSH) were observed during the senescence of detached young leaves. Triadimefon at concentration of 20 mg/L promoted the activities of POD, AsA-POD and levels of AsA and GSH, but had no effect on the activities of SOD and CAT. On the other hand, the levels of malondialdehyde (MDA) were increased and the increase of which was markedly negative correlated with the activities of POD, AsA-POD and with the contents of AsA and GSH during the senescence of leaves. MDA contents were decreased by triadimefon treatment. These resuits suggested that triadimefon retarded the senescence of leaves in mung bean seedlings in terms of enhancing the protective ability of plant tissues against membrane lipid peroxidation. 相似文献
19.
三唑酮对绿豆幼苗叶片衰老的延缓作用 总被引：26，自引：0，他引：26
三唑酮处理可提高离体绿豆（ＰｈａｓｅｏｌｕｓｒａｄｉａｔｕｓＬ．）幼苗叶片叶绿素和蛋白质含量。叶片衰老过程中超氧物歧化酶（ＳＯＤ）、过氧化物酶（ＰＯＤ）、过氧化氢酶（ＣＡＴ）和抗坏血酸过氧化物酶（ＡｓＡＰＯＤ）活性及抗坏血酸（ＡｓＡ）和还原型谷胱甘肽（ＧＳＨ）含量降低。２０ｍｇ／Ｌ三唑酮可提高ＰＯＤ、ＡｓＡＰＯＤ活性和ＡｓＡ、ＧＳＨ含量,对ＳＯＤ、ＣＡＴ活性无影响。丙二醛（ＭＤＡ）含量在叶片衰老过程中提高,并与ＰＯＤ、ＡｓＡＰＯＤ活性和ＡｓＡ、ＧＳＨ含量呈显著负相关,三唑酮可降低ＭＤＡ含量。表明三唑酮有提高植物对膜脂过氧化作用的保护能力,延缓叶片的衰老作用。 相似文献