real-time-detection-reactive-oxygen-species-production-immune

Real-Time Detection of Reactive Oxygen Species Production in Immune Response in Rice with a Chemiluminescence Assay

Reactive oxygen species (ROS) play vital roles in a variety of biological processes, including the sensing of abiotic and biotic stresses. Upon pathogen ...

Shanghai Jiao Tong University

The cuticle is the outermost layer of plant aerial tissue that interacts with the environment and protects plants against water loss and various biotic and abiotic stresses. ADP ribosylation factor guanine nucleotide exchange factor proteins (ARF-GEFs) are key components of the vesicle trafficking system. Our study discovers that AtMIN7, an  ARF-GEF, is critical for cuticle formation and related leaf surface defense against the bacterial pathogen  pathovar tomato (). Our transmission electron microscopy and scanning electron microscopy studies indicate that the  mutant leaves have a thinner cuticular layer, defective stomata structure, and impaired cuticle ledge of stomata compared to the leaves of wild type plants. GC-MS analysis further revealed that the amount of cutin monomers was significantly reduced in  mutant plants. Furthermore, the exogenous application of either of three plant hormones-salicylic acid, jasmonic acid, or abscisic acid-enhanced the cuticle formation in  mutant leaves and the related defense responses to the bacterial  infection. Thus, transport of cutin-related components by AtMIN7 may contribute to its impact on cuticle formation and related defense function.

Deciphering the Novel Role of AtMIN7 in Cuticle Formation and Defense against the Bacterial Pathogen Infection.

Plant fatty acids (FAs) and lipids are essential in storing energy and act as structural components for cell membranes and signaling molecules for plant growth and stress responses. Acyl carrier proteins (ACPs) are small acidic proteins that covalently bind the fatty acyl intermediates during the elongation of FAs. The  ACP family has eight members. Through reverse genetic, molecular, and biochemical approaches, we have discovered that ACP1 localizes to the chloroplast and limits the magnitude of pattern-triggered immunity (PTI) against the bacterial pathogen  pv. . Mutant  plants have reduced levels of linolenic acid (18:3), which is the primary precursor for biosynthesis of the phytohormone jasmonic acid (JA), and a corresponding decrease in the abundance of JA. Consistent with the known antagonistic relationship between JA and salicylic acid (SA),  mutant plants also accumulate a higher level of SA and display corresponding shifts in JA- and SA-regulated transcriptional outputs. Moreover, methyl JA and linolenic acid treatments cause an apparently enhanced decrease of resistance against  pv.  in  mutants than that in WT plants. The ability of ACP1 to prevent this hormone imbalance likely underlies its negative impact on PTI in plant defense. Thus, ACP1 links FA metabolism to stress hormone homeostasis to be negatively involved in PTI in  plant defense. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Involvement of  Acyl Carrier Protein 1 in PAMP-Triggered Immunity.

Plants evolve a prompt and robust immune system to defend themselves against pathogen infections. Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) is the first battle layer activated upon the PAMP's perception, which leads to multiple defense responses. The plasma membrane (PM) H-ATPases are the primary ion pumps to create and maintain the cellular membrane potential that is critical for various essential biological processes, including plant growth, development, and defense. This study discovered that the PM H-ATPase AHA5 is negatively involved in Arabidopsis PTI against the virulent pathogen  pvr.  () DC3000 infection. The  mutant plants caused the reduced stomata opening upon the  infection, which was associated with the salicylic acid (SA) pathway. In addition, the  mutant plants caused the increased levels of callose deposition, defense-related gene expression, and SA accumulation. Our results also indicate that the PM H-ATPase activity of AHA5 probably mediates the coupling of HO generation and the apoplast alkalization in PTI responses. Moreover, AHA5 was found to interact with a vital defense regulator, RPM1-interacting protein 4 (RIN4), in vitro and in vivo, which might also be critical for its function in PTI. In summary, our studies show that AHA5 functions as a novel and critical component that is negatively involved in PTI by coordinating different defense responses during the Arabidopsis- DC3000 interaction.

Jiangbo Fan

Shanghai Collaborative Innovation Center of Agri-Seeds,
School of Agriculture and Biology,
Joint Center for Single Cell Biology,
Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology,
Joint Center for Single Cell Biology, School of Agriculture and Biology

Shanghai Jiao Tong University

Real-Time Detection of Reactive Oxygen Species Production in Immune Response in Rice with a Chemiluminescence Assay

Jiangbo Fan

Shanghai Collaborative Innovation Center of Agri-Seeds,School of Agriculture and Biology,Joint Center for Single Cell Biology,Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology,Joint Center for Single Cell Biology, School of Agriculture and Biology

Shanghai Jiao Tong University

Real-Time Detection of Reactive Oxygen Species Production in Immune Response in Rice with a Chemiluminescence Assay

Shanghai Collaborative Innovation Center of Agri-Seeds,
School of Agriculture and Biology,
Joint Center for Single Cell Biology,
Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology,
Joint Center for Single Cell Biology, School of Agriculture and Biology