The type III effector RipB from
            Ralstonia solanacearum
            RS1000 acts as a major avirulence factor in
            Nicotiana benthamiana
            and other
            Nicotiana
            species

The plasma membrane (PM) is at the interface of plant–pathogen interactions and, thus, many bacterial type-III effector (T3E) proteins target membrane-associated processes to interfere with immunity. The Pseudomonas syringae T3E HopZ1a is a host cell PM-localized effector protein that has several immunity-associated host targets but also activates effector-triggered immunity in resistant backgrounds. Although HopZ1a has been shown to interfere with early defense signaling at the PM, no dedicated PM-associated HopZ1a target protein has been identified until now. Here, we show that HopZ1a interacts with the PM-associated remorin protein NbREM4 from Nicotiana benthamiana in several independent assays. NbREM4 relocalizes to membrane nanodomains after treatment with the bacterial elicitor flg22 and transient overexpression of NbREM4 in N. benthamiana induces the expression of a subset of defense-related genes. We can further show that NbREM4 interacts with the immune-related receptor-like cytoplasmic kinase avrPphB-susceptible 1 (PBS1) and is phosphorylated by PBS1 on several residues in vitro. Thus, we conclude that NbREM4 is associated with early defense signaling at the PM. The possible relevance of the HopZ1a–NbREM4 interaction for HopZ1a virulence and avirulence functions is discussed. [Formula: see text]Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Download Full-text

Ralstonia solanacearum type III effector RipV2 encoding a novel E3 ubiquitin ligase (NEL) is required for full virulence by suppressing plant PAMP-triggered immunity

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2021.02.082 ◽

2021 ◽

Vol 550 ◽

pp. 120-126

Author(s):

Dong Cheng ◽

Dan Zhou ◽

Yudan Wang ◽

Bingsen Wang ◽

Qin He ◽

...

Keyword(s):

Ubiquitin Ligase ◽

Ralstonia Solanacearum ◽

E3 Ubiquitin Ligase ◽

Type Iii Effector ◽

Type Iii

Download Full-text

SseF, a type III effector protein from the mammalian pathogen Salmonella enterica, requires resistance-gene-mediated signalling to activate cell death in the model plant Nicotiana benthamiana

New Phytologist ◽

10.1111/j.1469-8137.2012.04124.x ◽

2012 ◽

Vol 194 (4) ◽

pp. 1046-1060 ◽

Cited By ~ 25

Author(s):

Şuayib Üstün ◽

Petra Müller ◽

Ralf Palmisano ◽

Michael Hensel ◽

Frederik Börnke

Keyword(s):

Cell Death ◽

Resistance Gene ◽

Nicotiana Benthamiana ◽

Salmonella Enterica ◽

Effector Protein ◽

Type Iii Effector ◽

Model Plant ◽

Type Iii ◽

Activate Cell

Download Full-text

Opening the Ralstonia solanacearum type III effector tool box: insights into host cell subversion mechanisms

Current Opinion in Plant Biology ◽

10.1016/j.pbi.2014.05.002 ◽

2014 ◽

Vol 20 ◽

pp. 110-117 ◽

Cited By ~ 45

Author(s):

Laurent Deslandes ◽

Stephane Genin

Keyword(s):

Host Cell ◽

Ralstonia Solanacearum ◽

Type Iii Effector ◽

Type Iii

Download Full-text

Identification of novel Ralstonia solanacearum type III effector proteins through translocation analysis of hrpB-regulated gene products

Microbiology ◽

10.1099/mic.0.027763-0 ◽

2009 ◽

Vol 155 (7) ◽

pp. 2235-2244 ◽

Cited By ~ 33

Author(s):

Takafumi Mukaihara ◽

Naoyuki Tamura

Keyword(s):

Ralstonia Solanacearum ◽

Pathogenic Bacteria ◽

Tandem Repeats ◽

Plant Cells ◽

Secretion System ◽

Effector Proteins ◽

Gene Products ◽

Type Iii Effector ◽

Type Iii ◽

Effector Genes

The Hrp type III secretion system (TTSS) is essential for the pathogenicity of Ralstonia solanacearum on host plants. Hrp TTSS is a specialized secretion system that injects virulence proteins, the so-called type III effector proteins, into plant cells. In R. solanacearum, the expression of Hrp TTSS-related genes is regulated by an AraC-type transcriptional activator, HrpB. We have identified 30 hrpB-regulated hpx ( hrpB-dependent expression) genes and three well-known hrpB-regulated genes, popA, popB and popC, as candidate effector genes in R. solanacearum strain RS1000. In this study, we newly cloned 11 additional candidate effector genes that share homology with known hpx genes from R. solanacearum RS1000. Using a Cya reporter system, we investigated the translocation of these 44 gene products into plant cells via the Hrp TTSS and identified 34 effector proteins. These include three effector families composed of more than four members, namely the Hpx4, Hpx30 and GALA families. The Hpx30 family effectors are 2200–2500 aa in size and appear to be the largest class of effector proteins among animal- and plant-pathogenic bacteria. Members of this family contain 12–18 tandem repeats of a novel 42 aa motif, designated SKWP repeats.

Download Full-text