An unconventionally secreted effector from the root knot nematode Meloidogyne incognita, Mi-ISC-1, promotes parasitism by disrupting salicylic acid biosynthesis in host plants.
An unconventionally secreted effector from the root knot nematode Meloidogyne incognita, Mi-ISC-1, promotes parasitism by disrupting salicylic acid biosynthesis in host plants.
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根结线虫根结线虫 (Meloidogyne incognita) 的非常规分泌效应子 Mi-ISC-1 通过破坏宿主植物中的水杨酸生物合成来促进寄生
DOI：
10.1111/mpp.13175
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发表时间：
2022-04
影响因子：
4.9
通讯作者：
Wang X
中科院分区：
文献类型：
--
作者：
Qin X;Xue B;Tian H;Fang C;Yu J;Chen C;Xue Q;Jones J;Wang X
植物寄生线虫需要传递抑制宿主免疫的效应器才能成功寄生。我们从南方根结线虫中鉴定了一种新的异丝分裂酶效应子，命名为Mi-ISC-1。Mi-ISC-1基因在食道腺腹下表达，在寄生虫期幼虫中上调表达。针对Mi-ISC-1的烟草骚动病毒诱导的基因沉默可减弱南方根结线虫的寄生。酶活性测定表明，Mi-ISC-1在体外能催化异甲酸水解制2，3-二氢-2，3-二羟基苯甲酸酯。虽然Mi-ISC-1在其N端缺乏一个典型的分泌信号肽，但酵母转化酶分泌实验表明，该蛋白可以从真核细胞中分泌。然而，亚细胞定位和质解分析表明，存在于Mi-ISC-1上的非常规分泌信号不被植物分泌途径识别，当通过农业渗透在烟草叶片中瞬时表达时，效应器定位在植物细胞的细胞质中，而不是质外体中。Mi-ISC-1的异位表达降低了Pr1基因的表达和水杨酸(SA)水平，促进了辣椒疫霉菌的侵染。Mi-ISC-1的功能需要细胞质定位。此外，Mi-ISC-1通过胞质中的异鞭毛酸途径抑制了SA从头合成过程中SA的产生。这些结果表明，南方根结线虫通过破坏SA生物合成的同裂原酸合成酶途径来促进寄生，从而部署一种功能性的同裂链酶来抑制SA介导的植物防御。南方根结线虫Mi-ISC-1的线虫效应器能将细胞质内的异链氨基酸从接合转移到L-谷氨酸，从而阻断细胞质中水杨酸的生物合成。
Plant‐parasitic nematodes need to deliver effectors that suppress host immunity for successful parasitism. We have characterized a novel isochorismatase effector from the root‐knot nematode Meloidogyne incognita, named Mi‐ISC‐1. The Mi‐isc‐1 gene is expressed in the subventral oesophageal glands and is up‐regulated in parasitic‐stage juveniles. Tobacco rattle virus‐induced gene silencing targeting Mi‐isc‐1 attenuated M. incognita parasitism. Enzyme activity assays confirmed that Mi‐ISC‐1 can catalyse hydrolysis of isochorismate into 2,3‐dihydro‐2,3‐dihydroxybenzoate in vitro. Although Mi‐ISC‐1 lacks a classical signal peptide for secretion at its N‐terminus, a yeast invertase secretion assay showed that this protein can be secreted from eukaryotic cells. However, the subcellular localization and plasmolysis assay revealed that the unconventional secretory signal present on the Mi‐ISC‐1 is not recognized by the plant secretory pathway and that the effector was localized within the cytoplasm of plant cells, but not apoplast, when transiently expressed in Nicotiana benthamiana leaves by agroinfiltration. Ectopic expression of Mi‐ISC‐1 in N. benthamiana reduced expression of the PR1 gene and levels of salicylic acid (SA), and promoted infection by Phytophthora capsici. The cytoplasmic localization of Mi‐ISC‐1 is required for its function. Moreover, Mi‐ISC‐1 suppresses the production of SA following the reconstitution of the de novo SA biosynthesis via the isochorismate pathway in the cytoplasm of N. benthamiana leaves. These results demonstrate that M. incognita deploys a functional isochorismatase that suppresses SA‐mediated plant defences by disrupting the isochorismate synthase pathway for SA biosynthesis to promote parasitism. The nematode effector from the root‐knot nematode Meloidogyne incognita, Mi‐ISC‐1, diverts the cytoplasmic isochorismate away from conjugation to l‐glutamate, thus interrupting salicylic acid biosynthesis in the cytosol.
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影响因子：
3.5
作者：
Gleason, Cynthia;Polzin, Frederik;Elashry, Abdelnaser
通讯作者：
Elashry, Abdelnaser
DOI：
10.1073/pnas.85.20.7652
发表时间：
1988-10-01
影响因子：
11.1
作者：
GYLLENSTEN, UB;ERLICH, HA
通讯作者：
ERLICH, HA
马铃薯胞囊线虫效应子 RHA1B 是一种泛素连接酶，使用两种不同的机制来抑制植物免疫信号传导
影响因子：
6.7
作者：
Kud, Joanna;Wang, Wenjie;Xiao, Fangming
通讯作者：
Xiao, Fangming
影响因子：
3.5
作者：
Lambert, KN;Allen, KD;Sussex, IM
通讯作者：
Sussex, IM
DOI：
10.1007/s10969-012-9127-5
发表时间：
2012-03
期刊：
Journal of structural and functional genomics
影响因子：
--
作者：
Goral, Anna M;Tkaczuk, Karolina L;Chruszcz, Maksymilian;Kagan, Olga;Savchenko, Alexei;Minor, Wladek
通讯作者：
Minor, Wladek