A novel nematode effector suppresses plant immunity by activating host reactive oxygen species-scavenging system.
Evidence is emerging that plant-parasitic nematodes can secrete effectors to interfere with the host immune response, but it remains unknown how these effectors can conquer host immune responses. Here, we depict a novel effector, MjTTL5, that could suppress plant immune response. Immunolocalization and transcriptional analyses showed that MjTTL5 is expressed specifically within the subventral gland of Meloidogyne javanica and up-regulated in the early parasitic stage of the nematode. Transgenic Arabidopsis lines expressing MjTTL5 were significantly more susceptible to M. javanica infection than wild-type plants, and vice versa, in planta silencing of MjTTL5 substantially increased plant resistance to M. javanica. Yeast two-hybrid, coimmunoprecipitation and bimolecular fluorescent complementation assays showed that MjTTL5 interacts specifically with Arabidopsis ferredoxin : thioredoxin reductase catalytic subunit (AtFTRc), a key component of host antioxidant system. The expression of AtFTRc is induced by the infection of M. javanica. Interaction between AtFTRc and MjTTL could drastically increase host reactive oxygen species-scavenging activity, and result in suppression of plant basal defenses and attenuation of host resistance to the nematode infection. Our results demonstrate that the host ferredoxin : thioredoxin system can be exploited cunningly by M. javanica, revealing a novel mechanism utilized by plant-parasitic nematodes to subjugate plant innate immunity and thereby promoting parasitism.
Laboratory of Plant Nematology, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.
Borong
B
Lin
Laboratory of Plant Nematology, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.
Kan
K
Zhuo
School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA.
Shiyan
S
Chen
Laboratory of Plant Nematology, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.
Lili
L
Hu
Laboratory of Plant Nematology, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.
Longhua
L
Sun
School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA.|Robert W. Holley Center for Agriculture and Health, US Department of Agriculture, Agricultural Research Service, Ithaca, NY, 14853, USA.
Xiaohong
X
Wang
Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.|Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore.
Lian-Hui
LH
Zhang
Laboratory of Plant Nematology, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China.|Guangdong Vocational College of Ecological Engineering, Guangzhou, 510520, China.
Jinling
J
Liao
D000818:Animals; D017360:Arabidopsis / Q000235:genetics / Q000276:immunology / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000378:metabolism; D001499:Bayes Theorem; D003001:Cloning, Molecular; D003198:Computer Simulation; D060467:Disease Resistance; D016166:Free Radical Scavengers / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017238:Genes, Helminth; D017343:Genes, Plant; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006790:Host-Parasite Interactions; D006861:Hydrogen Peroxide / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D010271:Parasites; D000069452:Pathogen-Associated Molecular Pattern Molecules; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D057865:Plant Immunity; D011485:Protein Binding; D000072417:Protein Domains; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014431:Tylenchoidea / Q000235:genetics / Q000502:physiology*; D015854:Up-Regulation
D029681:Arabidopsis Proteins; D016166:Free Radical Scavengers; D015801:Helminth Proteins; D000069452:Pathogen-Associated Molecular Pattern Molecules; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide
Arabidopsis thaliana; Meloidogyne javanica; ferredoxin : thioredoxin reductase catalytic subunit; pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI); reactive oxygen species (ROS); transthyretin-like protein (TTL)