Proteins responsive to <i>B</i>. <i>maydis</i> and its predicted multiple subcellular locations.

<p>A) A conceptual diagram of a systematic NHR of soybean against <i>B</i>. <i>maydis</i>. H₂O₂ production and callose deposition were processed upon the interaction between soybean and <i>B</i>. <i>maydis</i> starting at the cell wall of soybean. The subcellular locations of the differentially expressed proteins were predicted. Changed proteins are shown in italics, and the organelle is written in blue. For instance, Hsp 70 was predicted to exist in chloroplasts and mitochondria. All of the major organelles responded to <i>B</i>. <i>maydis</i>. B) Venn diagram representing the differentially expressed proteins found in the leaves, stems, and roots of soybean plants. An L, S, or R character was placed before the spots (corresponding to the 2-DE pattern) corresponding to leaf, stem, and root proteins. Two pairs of leaf and stem protein spots were attributed to the same protein, L17 and S24, and L34 and S7. There was only one pair of stem and root protein spots that was attributed to the same protein, S15 and R13. However, no protein overlap between leaf and root was detected.</p

Proteomic Analysis of the Relationship between Metabolism and Nonhost Resistance in Soybean Exposed to <i>Bipolaris maydis</i>

<div><p>Nonhost resistance (NHR) pertains to the most common form of plant resistance against pathogenic microorganisms of other species. <i>Bipolaris maydis</i> is a non-adapted pathogen affecting soybeans, particularly of maize/soybean intercropping systems. However, no experimental evidence has described the immune response of soybeans against <i>B</i>. <i>maydis</i>. To elucidate the molecular mechanism underlying NHR in soybeans, proteomics analysis based on two-dimensional polyacrylamide gel electrophoresis (2-DE) was performed to identify proteins involved in the soybean response to <i>B</i>. <i>maydis</i>. The spread of <i>B</i>. <i>maydis</i> spores across soybean leaves induced NHR throughout the plant, which mobilized almost all organelles and various metabolic processes in response to <i>B</i>. <i>maydis</i>. Some enzymes, including ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), mitochondrial processing peptidase (MPP), oxygen evolving enhancer (OEE), and nucleoside diphosphate kinase (NDKs), were found to be related to NHR in soybeans. These enzymes have been identified in previous studies, and STRING analysis showed that most of the protein functions related to major metabolic processes were induced as a response to <i>B</i>. <i>maydis</i>, which suggested an array of complex interactions between soybeans and <i>B</i>. <i>maydis</i>. These findings suggest a systematic NHR against non-adapted pathogens in soybeans. This response was characterized by an overlap between metabolic processes and response to stimulus. Several metabolic processes provide the soybean with innate immunity to the non-adapted pathogen, <i>B</i>. <i>maydis</i>. This research investigation on NHR in soybeans may foster a better understanding of plant innate immunity, as well as the interactions between plant and non-adapted pathogens in intercropping systems.</p></div

Proteins in soybean roots in response to the challenge of <i>B</i>. <i>maydis</i> on leaves.

<p>Proteins in soybean roots in response to the challenge of <i>B</i>. <i>maydis</i> on leaves.</p

Predicted locations of differentially expressed proteins in soybean to <i>B</i>. <i>maydis</i>.

<p>Some proteins are predicted in multiple locations, which could be located in chloroplast and mitochondrion.</p><p>Predicted locations of differentially expressed proteins in soybean to <i>B</i>. <i>maydis</i>.</p

<i>Arabidopsis</i> DB-based BLAST analysis of the interaction network of 64 differentially expressed proteins in the roots, stems, and leaves of soybean plants in response to <i>B</i>. <i>maydis</i>.

<p>GO analysis indicated that the 38 red nodes in A might be involved in metabolic processes (P value = 1.070e ⁻¹⁰). Another 35 red nodes in B were involved in stimulus response (P value = 3.970e ⁻¹⁰). Thirty proteins belonged to the both metabolic process and response to stimulus, which suggested that the same protein could perform different functions in soybean plants in response to <i>B</i>. <i>maydis</i> stress.</p

Two DE patterns of stem proteins responding to <i>B</i>. <i>maydis</i>.

<p>S7 and S2 show enlarged images of protein spots 7 and 2, which were differentially expressed under <i>B</i>. <i>maydis</i> stress conditions; “C” refers to the protein pattern dissolved on the control gel, and “T” to the protein pattern dissolved on the treatment gel. The differential abundance of proteins was read using the PDQuest software and is plotted as the relative intensity enumerated in E7 and E2. E7 and E2 represent the relative expression of protein spots 7 and 2 in the control and treatment groups. “C” also refers to the control, and “T” to treatment. S7/E7 and S2/E2 are representative images of the differentially expressed proteins in the stems of soybean plants.</p

Two-DE map of root proteins responding to <i>B</i>. <i>maydis</i>.

<p>S1 and S15 were zoomed in the protein spot 1 and spot 15 differentially expressed under the <i>B</i>. <i>maydis</i> stress; “C” refers to the protein spot excised from the control gel, and “T” refers to the protein spot excised from the treatment gel. The differential abundance of proteins was determined using the PDQuest software and was plotted as the relative intensity enumerated as ES1 and ES15. ES1 and ES15 represent the relative expression between control and treatment of protein spot 1 and spot 15, “C” means control, and “T” indicates treatment. S1/ES1 and S15/ES15 are representative differentially expressed root proteins.</p

The result of Gene-set enrichment analysis on functional categories.

<p>The result of Gene-set enrichment analysis on functional categories.</p

The effects of activated charcoal (AC) on the survival rate of Sanqi ginseng plants that were grown in water or root exudates (REs) with or without AC.

<p>The means and standard errors are shown. Asterisks indicate statistically significant difference of treatment compared with water control. *, <i>p</i> < 0.05; **, <i>p</i> < 0.01, LSD test.</p

Cell deaths in the Sanqi ginseng root tips after treatment with ginsenosides.

<p>Roots were treated with R₁, Rg₁, Re, Rb₁, Rb₃, Rg₂, Rh₁, and Rd at a concentration of 1.0 μg mL^-1 for 24 h and then stained with PI (5.0 μg mL^-1). Cell nuclei that stained with PI indicated dead cells (red).</p