Search results for "plant immunity"

Free Radicals Mediate Systemic Acquired Resistance

2014

Summary: Systemic acquired resistance (SAR) is a form of resistance that protects plants against a broad spectrum of secondary infections. However, exploiting SAR for the protection of agriculturally important plants warrants a thorough investigation of the mutual interrelationships among the various signals that mediate SAR. Here, we show that nitric oxide (NO) and reactive oxygen species (ROS) serve as inducers of SAR in a concentration-dependent manner. Thus, genetic mutations that either inhibit NO/ROS production or increase NO accumulation (e.g., a mutation in S-nitrosoglutathione reductase [GSNOR]) abrogate SAR. Different ROS function additively to generate the fatty-acid-derived azel…

Study of the role of the CDC48 chaperone protein in plant immunity

2018

The chaperone protein CDC48 (Cell division cycle 48) is a major regulator of the quality control of proteins and is involved in various cellular processes in animals and yeast. In contrast, the role of CDC48 in plants is poorly known. In the present work, we investigated the function of CDC48 in plant immunity thanks to the cryptogein/tobacco biological model, cryptogein being produced by the oomycete phytophthora cryptogea.Three strategies were carried out. First, the dynamic of accumulation CDC48 together with intracellular events inherent to the immune response were analyzed in both wild-type and CDC48 overexpressing tobacco cells (CDC48-TAP line). Second, a list if CDC48 partners was es…

Analysis of the role of nitric oxide (NO) in the cross‐regulation between immunity, growth and iron homeostasis in plants

2019

Studies performed in our Agroecology Department show that the immune response of plants is linked to their iron nutrition and is modulated by pyoverdine, a siderophore produced by the plant beneficial rhizobacteria Pseudomonas fluorescens C7R12. Accordingly, Arabidopsis thaliana plantlets exposed to iron deficiency and treated with pyoverdine in its iron non‐chelated structure (apo‐pyo) show an enhanced growth but a decreased immune response capacity. We hypothesize that nitric oxide (NO), a universal signaling molecule, is a key component of the regulation of the immune response in plants exposed to apo‐pyo and to the C7R12 strain. We checked by fluorescence microscopy that NO is actually …

Study of the stress-related signalling of endoplasmic reticulum in grapevine immunity associated to LysM receptor kinases (VvLYKs)

2023

In the actual situation of decreasing the use of chemicals in agriculture, enhancing our understanding of plant immunity is a critical task to develop more sustainable plant health protection methods. An interesting strategy is to study how plants, and in particular grapevine, perceives and responds to different microorganisms. Microorganisms are notably recognizedby LysM Receptor-like Kinase (LYKs) and previous works have identified 16 LYKs encoded by the grapevine genome (VvLYKs) (Roudaire et al. 2023). Among them, VvLYK1-1, VvLYK1-2 and VvLYK5-1 are involved in chitin perception and thus play a role in the plant immunity. Interestingly, immune responses are also involved during symbiotic…

New insights about the role of the chaperon-like protein Cdc48, a target for nitric oxide in plant immunity

2015

Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays.

2014

International audience; Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of "PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type" oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as…

NO signaling in cryptogein-induced immune responses in tobacco

2014

SPEIPM; International audience

Cryptogein signaling in tobacco: in search for nitric oxide targets

2013

Nitric oxide (NO) triggers various physiological responses in plants. Notably, NO is recognized to account for the response to biotic stresses. We previously reported that NO is produced in tobacco cells exposed to cryptogein, a 10 kDa elicitor secreted by the oomycete Phytophthora cryptogea. To decipher the role of NO, we identified and characterized S-nitrosylated proteins in tobacco cell suspensions elicited by cryptogein. Several candidates were identified including the chaperone-like AAA+ATPase CDC48 and a calmodulin isoform (CaM). Interestingly, the Cys residue undergoing S-nitrosylation in CaM is located in the first Ca2+ binding EF hand and is not or poorly conserved in other organi…

Nuclear involvement of the Cell Division Cycle 48 protein during the plant immune response

2023

The control of protein homeostasis, a balance between their synthesis and degradation, also called proteostasis, is essential for cell survival. Any imbalance of the proteome, for instance triggered by a stress, leads to an accumulation of misfolded proteins leading to proteotoxic stress that can induce cell death. The ubiquitin proteasome system (UPS) is a major actor in the selective degradation of misfolded proteins to preserve proteome balance.The chaperone-like Cdc48 is a member of the AAA+ ATPase enzyme family which isconserved in mammals (VCP), yeasts and plants (Cdc48: Cell Division Cycle 48/p97).Cdc48/VCP is a cytosolic and nuclear protein which segregates misfolded proteins fromsu…

Comparison between tumors in plants and human beings: Mechanisms of tumor development and therapy with secondary plant metabolites

2019

Abstract Background Human tumors are still a major threat to human health and plant tumors negatively affect agricultural yields. Both areas of research are developing largely independent of each other. Treatment of both plant and human tumors remains unsatisfactory and novel therapy options are urgently needed. Hypothesis The concept of this paper is to compare cellular and molecular mechanisms of tumor development in plants and human beings and to explore possibilities to develop novel treatment strategies based on bioactive secondary plant metabolites. The interdisciplinary discourse may unravel commonalities and differences in the biology of plant and human tumors as basis for rational …