12 research outputs found
Characterization of Storage Proteins in Wild (\u3ci\u3eGlycine soja\u3c/i\u3e) and Cultivated (\u3ci\u3eGlycine max\u3c/i\u3e) Soybean Seeds Using Proteomic Analysis
A combined proteomic approach was applied for the separation, identification, and comparison of two major storage proteins, β-conglycinin and glycinin, in wild (Glycine soja) and cultivated (Glycine max) soybean seeds. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with three different immobilized pH gradient (IPG) strips was an effective method to separate a large number of abundant and less-abundant storage proteins. Most of the subunits of β-conglycinin were well separated in the pH range 3.0-10.0, while acidic and basic glycinin polypeptides were well-separated in pH ranges 4.0-7.0 and 6.0-11.0, respectively. Although the overall distribution pattern of the protein spots was similar in both genotypes using pH 3.0-10.0, variations in number and intensity of protein spots were better resolved using a combination of pH 4.0-7.0 and pH 6.0-11.0. The total number of storage protein spots detected in wild and cultivated genotypes was approximately 44 and 34, respectively. This is the first study reporting the comparison of protein profiles of wild and cultivated genotypes of soybean seeds using proteomic tools
Gene expression profiling of the plant pathogenic basidiomycetous fungus \u3ci\u3eRhizoctonia solani\u3c/i\u3e AG 4 reveals putative virulence factors
Rhizoctonia solani is a ubiquitous basidiomycetous soilborne fungal pathogen causing damping- off of seedlings, aerial blights and postharvest diseases. To gain insight into the molecular mechanisms of pathogenesis a global approach based on analysis of expressed sequence tags (ESTs) was undertaken. To get broad gene-expression coverage, two normalized EST libraries were developed from mycelia grown under high nitrogen-induced virulent and low nitrogen/methylglucose-induced hypovirulent conditions. A pilot-scale assessment of gene diversity was made from the sequence analyses of the two libraries. A total of 2280 cDNA clones was sequenced that corresponded to 220 unique sequence sets or clusters (contigs) and 805 singlets, making up a total of 1025 unique genes identified from the two virulence-differentiated cDNA libraries. From the total sequences, 295 genes (38.7%) exhibited strong similarities with genes in public databases and were categorized into 11 functional groups. Approximately 61.3% of the R. solani ESTs have no apparent homologs in publicly available fungal genome databases and are considered unique genes. We have identified several cDNAs with potential roles in fungal pathogenicity, virulence, signal transduction, vegetative incompatibility and mating, drug resistance, lignin degradation, bioremediation and morphological differentiation. A codon-usage table has been formulated based on 14 694 R. solani EST codons. Further analysis of ESTs might provide insights into virulence mechanisms of R. solani AG 4 as well as roles of these genes in development, saprophytic colonization and ecological adaptation of this important fungal plant pathogen
Proteomic analysis of the pulvinus, a heliotropic tissue, in Glycine max
Certain plant species respond to light, dark, and other environmental factors by leaf movement. Leguminous plants both track and avoid the sun through turgor changes of the pulvinus tissue at the base of leaves. Mechanisms leading to pulvinar turgor flux, particularly knowledge of the proteins involved, are not well-known. In this study we used two-dimensional gel electrophoresis and liquid chromatography-tandom mass spectrometry to separate and identify the proteins located in the soybean pulvinus. A total of 183 spots were separated and 195 proteins from 165 spots were identified and functionally analyzed using single enrichment analysis for gene ontology terms. The most significant terms were related to proton transport. Comparison with guard cell proteomes revealed similar significant processes but a greater number of pulvinus proteins are required for comparable analysis. To our knowledge, this is a novel report on the analysis of proteins found in soybean pulvinus. These findings provide a better understanding of the proteins required for turgor change in the pulvinus
Biochemical and Anatomical Investigation of Sesbania herbacea (Mill.) McVaugh Nodules Grown under Flooded and Non-Flooded Conditions
Sesbania herbacea, a native North American fast-growing legume, thrives in wet and waterlogged conditions. This legume enters into symbiotic association with rhizobia, resulting in the formation of nitrogen-fixing nodules on the roots. A flooding-induced anaerobic environment imposes a challenge for the survival of rhizobia and negatively impacts nodulation. Very little information is available on how S. herbacea is able to thrive and efficiently fix N2 in flooded conditions. In this study, we found that Sesbania plants grown under flooded conditions were significantly taller, produced more biomass, and formed more nodules when compared to plants grown on dry land. Transmission electron microscopy of Sesbania nodules revealed bacteroids from flooded nodules contained prominent polyhydroxybutyrate crystals, which were absent in non-flooded nodules. Gas and ion chromatography mass spectrometry analysis of nodule metabolites revealed a marked decrease in asparagine and an increase in the levels of gamma aminobutyric acid in flooded nodules. 2-D gel electrophoresis of nodule bacteroid proteins revealed flooding-induced changes in their protein profiles. Several of the bacteroid proteins that were prominent in flooded nodules were identified by mass spectrometry to be members of the ABC transporter family. The activities of several key enzymes involved in nitrogen metabolism was altered in Sesbania flooded nodules. Aspartate aminotransferase (AspAT), an enzyme with a vital role in the assimilation of reduced nitrogen, was dramatically elevated in flooded nodules. The results of our study highlight the potential of S. herbacea as a green manure and sheds light on the morphological, structural, and biochemical adaptations that enable S. herbacea to thrive and efficiently fix N2 in flooded conditions
Proteomic Analysis of Pigeonpea (Cajanus cajan) Seeds Reveals the Accumulation of Numerous Stress-Related Proteins
Pigeonpea
is one of the major sources of dietary protein for more
than a billion people living in South Asia. This hardy legume is often
grown in low-input and risk-prone marginal environments. Considerable
research effort has been devoted by a global research consortium to
develop genomic resources for the improvement of this legume crop.
These efforts have resulted in the elucidation of the complete genome
sequence of pigeonpea. Despite these developments, little is known
about the seed proteome of this important crop. Here, we report the
proteome of pigeonpea seed. To enable the isolation of maximum number
of seed proteins, including those that are present in very low amounts,
three different protein fractions were obtained by employing different
extraction media. High-resolution two-dimensional (2-D) electrophoresis
followed by MALDI-TOF-TOF-MS/MS analysis of these protein fractions
resulted in the identification of 373 pigeonpea seed proteins. Consistent
with the reported high degree of synteny between the pigeonpea and
soybean genomes, a large number of pigeonpea seed proteins exhibited
significant amino acid homology with soybean seed proteins. Our proteomic
analysis identified a large number of stress-related proteins, presumably
due to its adaptation to drought-prone environments. The availability
of a pigeonpea seed proteome reference map should shed light on the
roles of these identified proteins in various biological processes
and facilitate the improvement of seed composition
Proteomic Investigation of Rhizoctonia solani AG 4 Identifies Secretome and Mycelial Proteins with Roles in Plant Cell Wall Degradation and Virulence
Rhizoctonia solani AG 4 is a soilborne
necrotrophic fungal plant pathogen that causes economically important
diseases on agronomic crops worldwide. This study used a proteomics
approach to characterize both intracellular proteins and the secretome
of <i>R. solani</i> AG 4 isolate Rs23A under several
growth conditions, the secretome being highly important in pathogenesis.
From over 500 total secretome and soluble intracellular protein spots
from 2-D gels, 457 protein spots were analyzed and 318 proteins positively
matched with fungal proteins of known function by comparison with
available <i>R. solani</i> genome databases specific
for anastomosis groups 1-IA, 1-IB, and 3. These proteins were categorized
to possible cellular locations and functional groups and for some
proteins their putative roles in plant cell wall degradation and virulence.
The majority of the secreted proteins were grouped to extracellular
regions and contain hydrolase activity