Proteome Changes Reveal the Protective Roles of Exogenous Citric Acid in Alleviating Cu Toxicity in Brassica napus L

Identification of the succinate-CoA ligase protein gene family reveals that TaSUCL1-1 positively regulate cadmium resistance in wheat

The Succinate-CoA ligase (SUCL1) gene family is involved in energy metabolism, phytohormone signaling, and plant growth, development, and tolerance to stress. This is the first study to analyze the SUCL1 gene family in wheat (Triticum aestivum). 17 TaSUCL1 genes were identified in the complete genome sequence and classified into five subfamilies based on related genes found in three other species. The 17 TaSUCL1 genes were unevenly distributed across 11 chromosomes, and the collinearity of these genes was further investigated. Through using real-time qPCR (RT-qPCR) analysis, we identified the expression patterns of the TaSUCL1 genes under various tissues and different heavy metal stress conditions. The functions of selected TaSUCL1-1 gene were investigated by RNA interference (RNAi). This study provided a comprehensive analysis of the TaSUCL1 gene family. Within the TaSUCL1 genes, the exon-intron structure and motif composition exhibited significant similarity among members of the same evolutionary branch. Homology analysis and phylogenetic comparison of the SUCL1 genes in different plants offered valuable insights for studying the evolutionary characteristics of the SUCL1 genes. The expression levels of the TaSUCL1 genes in different tissues and under various metal stress conditions reveal its important role in plant growth and development. Gene function analysis demonstrated that TaSUCL1-1 silenced wheat plants exhibited a decrease in the total cadmium (Cd) concentrations and gene expression levels compared to the wild type (WT). Additionally, TaSUCL1-1 belonging to class c physically interacts with the β-amylase protein TaBMY1 as verified by yeast two-hybridization. This research provides a useful resource for further study of the function and molecular genetic mechanism of the SUCL1 gene family members.

How plants respond to heavy metal contamination: a narrative review of proteomic studies and phytoremediation applications

MAIN CONCLUSION

Heavy metal pollution caused by human activities is a serious threat to the environment and human health. Plants have evolved sophisticated defence systems to deal with heavy metal stress, with proteins and enzymes serving as critical intercepting agents for heavy metal toxicity reduction. Proteomics continues to be effective in identifying markers associated with stress response and metabolic processes. This review explores the complex interactions between heavy metal pollution and plant physiology, with an emphasis on proteomic and biotechnological perspectives. Over the last century, accelerated industrialization, agriculture activities, energy production, and urbanization have established a constant need for natural resources, resulting in environmental degradation. The widespread buildup of heavy metals in ecosystems as a result of human activity is especially concerning. Although some heavy metals are required by organisms in trace amounts, high concentrations pose serious risks to the ecosystem and human health. As immobile organisms, plants are directly exposed to heavy metal contamination, prompting the development of robust defence mechanisms. Proteomics has been used to understand how plants react to heavy metal stress. The development of proteomic techniques offers promising opportunities to improve plant tolerance to toxicity from heavy metals. Additionally, there is substantial scope for phytoremediation, a sustainable method that uses plants to extract, sequester, or eliminate contaminants in the context of changes in protein expression and total protein behaviour. Changes in proteins and enzymatic activities have been highlighted to illuminate the complex effects of heavy metal pollution on plant metabolism, and how proteomic research has revealed the plant's ability to mitigate heavy metal toxicity by intercepting vital nutrients, organic substances, and/or microorganisms.

Understanding the Proteomes of Plant Development and Stress Responses in Brassica Crops

Brassica crops have great economic value due to their rich nutritional content and are therefore grown worldwide as oilseeds, vegetables, and condiments. Deciphering the molecular mechanisms associated with the advantageous phenotype is the major objective of various Brassica improvement programs. As large technological advancements have been achieved in the past decade, the methods to understand molecular mechanisms underlying the traits of interest have also taken a sharp upturn in plant breeding practices. Proteomics has emerged as one of the preferred choices nowadays along with genomics and other molecular approaches, as proteins are the ultimate effector molecules responsible for phenotypic changes in living systems, and allow plants to resist variable environmental stresses. In the last two decades, rapid progress has been made in the field of proteomics research in Brassica crops, but a comprehensive review that collates the different studies is lacking. This review provides an inclusive summary of different proteomic studies undertaken in Brassica crops for cytoplasmic male sterility, oil content, and proteomics of floral organs and seeds, under different biotic and abiotic stresses including post-translational modifications of proteins. This comprehensive review will help in understanding the role of different proteins in controlling plant phenotypes, and provides information for initiating future studies on Brassica breeding and improvement programs.

Multi-Omics Uncover the Mechanism of Wheat under Heavy Metal Stress

Environmental pollution of heavy metals has received growing attention in recent years. Heavy metals such as cadmium, lead and mercury can cause physiological and morphological disturbances which adversely affect the growth and quality of crops. Wheat (Triticum aestivum L.) can accumulate high contents of heavy metals in its edible parts. Understanding wheat response to heavy metal stress and its management in decreasing heavy metal uptake and accumulation may help to improve its growth and grain quality. Very recently, emerging advances in heavy metal toxicity and phytoremediation methods to reduce heavy metal pollution have been made in wheat. Especially, the molecular mechanisms of wheat under heavy metal stress are increasingly being recognized. In this review, we focus on the recently described epigenomics, transcriptomics, proteomics, metabolomics, ionomics and multi-omics combination, as well as functional genes uncovering heavy metal stress in wheat. The findings in this review provide some insights into challenges and future recommendations for wheat under heavy metal stress.

Photosynthetic Characteristics and Chloroplast Ultrastructure Responses of Citrus Leaves to Copper Toxicity Induced by Bordeaux Mixture in Greenhouse

Bordeaux mixture (Bm) is a copper (Cu)-based pesticide that has been widely used for controlling citrus scab and citrus canker. However, frequent spraying of Bm is toxic to citrus. To our knowledge, few studies are available that discuss how the photosynthetic characteristics and chloroplast ultrastructure of citrus leaves are affected by Cu toxicity induced by excessive Bm. In the study, two-year-old seedlings of Citrus grandis (C. grandis) and Citrus sinensis (C. sinensis), which were precultured in pots, were foliar-sprayed with deionized water (as control) or Bm diluted 500-fold at intervals of 7 days for 6 times (4 times as recommended by the manufacturer) to investigate the leaf Cu absorption, photosynthesis, chloroplast ultrastructure and antioxidant enzymatic activities. Bm foliar-sprayed 6 times on citrus seedlings increased the leaf Cu content, decreased the photosynthetic pigments content and destroyed the chloroplast ultrastructure, which induced leaf chlorosis and photosynthetic inhibition. A lower Cu absorption, a higher light photon-electron transfer efficiency, a relative integrity of chloroplast ultrastructure and a promoted antioxidant protection contributed to a higher photosynthetic activity of C. grandis than C. sinensis under excessive spraying of Bm. The present study provides crucial references for screening and selecting citrus species with a higher tolerance to Cu toxicity induced by excessive Bm.

Label-free proteomics approach reveals candidate proteins in rice (Oryza sativa L.) important for ACC deaminase producing bacteria-mediated tolerance against salt stress

The omics-based studies are important for identifying characteristic proteins in plants to elucidate the mechanism of ACC deaminase producing bacteria-mediated salt tolerance. This study evaluates the changes in the proteome of rice inoculated with ACC deaminase producing bacteria under salt stress conditions. Salt stress resulted in a significant decrease in photosynthetic pigments, whereas inoculation of Methylobacterium oryzae CBMB20 had significantly increased pigment contents under normal and salt stress conditions. A total of 76, 51 and 33 differentially abundant proteins (DAPs) were identified in non-inoculated salt stressed plants, bacteria inoculated plants under normal and salt stress conditions, respectively. The abundances of proteins responsible for ethylene emission and programmed cell death were increased, and that of photosynthesis-related proteins were decreased in non-inoculated plants under salt stress. Whereas, bacteria-inoculated plants had shown higher abundance of antioxidant proteins, RuBisCo and ribosomal proteins that are important for enhancing stress tolerance and improving plant physiological traits. Collectively, salt stress might affect plant physiological traits by impairing photosynthetic machinery and accelerating apoptosis leading to a decline in biomass. However, inoculation of plants with bacteria can assist in enhancing photosynthetic activity, antioxidant activities and ethylene regulation related proteins for attenuating salt induced apoptosis and sustaining growth and development. This article is protected by copyright. All rights reserved.