pv. causes halo blight disease in the common bean . The bacterium invades the leaf apoplast and uses a type III secretion system to inject effector proteins into a bean cell to interfere with the bean immune system.
View Article and Find Full Text PDFMol Plant Microbe Interact
September 2020
Halo blight disease of beans is caused by a gram-negative bacterium, pv. . The disease is prevalent in South America and Africa and causes crop loss for indigent people who rely on beans as a primary source of daily nutrition.
View Article and Find Full Text PDFMol Plant Microbe Interact
April 2020
The common bean rust fungus reduces harvests of the dry, edible common bean. Natural resistance genes in the plant can provide protection until a fungal strain that breaks resistance emerges. In this study, we demonstrate that benzo(1,2,3)thiadiazole-7-carbothioic acid -methyl ester (BTH) sprayed on susceptible beans induces resistance to common bean rust.
View Article and Find Full Text PDFMol Cell Proteomics
February 2020
The blue mold fungus, is a postharvest apple pathogen that contributes to food waste by rotting fruit and by producing harmful mycotoxins ( patulin). To identify genes controlling pathogen virulence, a random T-DNA insertional library was created from wild-type strain R19. One transformant, T625, had reduced virulence in apples, blistered mycelial hyphae, and a T-DNA insertion that abolished transcription of the single copy locus in which it was inserted.
View Article and Find Full Text PDFPre-mRNA alternative splicing is a conserved mechanism for eukaryotic cells to leverage existing genetic resources to create a diverse pool of protein products. It is regulated in coordination with other events in RNA metabolism such as transcription, polyadenylation, RNA transport, and nonsense-mediated decay protein networks. SERINE/ARGININE-RICH 45 (SR45) is thought to be a neutral splicing regulator.
View Article and Find Full Text PDFStaphylococcus aureus, a bacterial, food-borne pathogen of humans, can contaminate raw fruits and vegetables. While physical and chemical methods are available to control S. aureus, scientists are searching for inhibitory phytochemicals from plants.
View Article and Find Full Text PDFMol Plant Microbe Interact
March 2018
Rhizobia colonize legumes and reduce N to NH in root nodules. The current model is that symbiotic rhizobia bacteroids avoid assimilating this NH. Instead, host legume cells form glutamine from NH, and the nitrogen is returned to the bacteroid as dicarboxylates, peptides, and amino acids.
View Article and Find Full Text PDFThe plant-pathogenic fungi Uromyces appendiculatus and Phakopsora pachyrhizi cause debilitating rust diseases on common bean and soybean. These rust fungi secrete effector proteins that allow them to infect plants, but their effector repertoires are not understood. The discovery of rust fungus effectors may eventually help guide decisions and actions that mitigate crop production loss.
View Article and Find Full Text PDFSystemic acquired resistance (SAR) is an enhanced defence response triggered when plants detect a pathogen. The response is extended to uninfected organs to protect against future attack. NPR1 is a nuclear leucine-rich repeat protein with a key role in SAR.
View Article and Find Full Text PDFPlant endo-β-1,4-glucanases (EGases) include cell wall-modifying enzymes that are involved in nematode-induced growth of syncytia (feeding structures) in nematode-infected roots. EGases in the α- and β-subfamilies contain signal peptides and are secreted, whereas those in the γ-subfamily have a membrane-anchoring domain and are not secreted. The Arabidopsis α-EGase At1g48930, designated as AtCel6, is known to be down-regulated by beet cyst nematode (Heterodera schachtii) in Arabidopsis roots, whereas another α-EGase, AtCel2, is up-regulated.
View Article and Find Full Text PDFBackground: Extensive studies using the model system Arabidopsis thaliana to elucidate plant defense signaling and pathway networks indicate that salicylic acid (SA) is the key hormone triggering the plant defense response against biotrophic and hemi-biotrophic pathogens, while jasmonic acid (JA) and derivatives are critical to the defense response against necrotrophic pathogens. Several reports demonstrate that SA limits nematode reproduction.
Results: Here we translate knowledge gained from studies using Arabidopsis to soybean.
During pathogen attack, the host plant induces genes to ward off the pathogen while the pathogen often produces effector proteins to increase susceptibility of the host. Gene expression studies of syncytia formed in soybean root by soybean cyst nematode (Heterodera glycines) identified many genes altered in expression in resistant and susceptible roots. However, it is difficult to assess the role and impact of these genes on resistance using gene expression patterns alone.
View Article and Find Full Text PDFHost-mediated (hm) expression of parasite genes as tandem inverted repeats was investigated as a means to abrogate the formation of mature Heterodera glycines (soybean cyst nematode) female cysts during its infection of Glycine max (soybean). A Gateway-compatible hm plant transformation system was developed specifically for these experiments in G. max.
View Article and Find Full Text PDFOur laboratory has been working toward increasing our understanding of the genetic control of cold hardiness in blueberry (Vaccinium section Cyanococcus) to ultimately use this information to develop more cold hardy cultivars for the industry. Here, we report using cDNA microarrays to monitor changes in gene expression at multiple times during cold acclimation under field and cold room conditions. Microarrays contained over 2,500 cDNA inserts, approximately half of which had been picked and single-pass sequenced from each of two cDNA libraries that were constructed from cold acclimated floral buds and non-acclimated floral buds of the fairly cold hardy cv.
View Article and Find Full Text PDFChanges in gene expression within roots of Glycine max (soybean), cv. Kent, susceptible to infection by Heterodera glycines (the soybean cyst nematode [SCN]), at 6, 12, and 24 h, and 2, 4, 6, and 8 days post-inoculation were monitored using microarrays containing more than 6,000 cDNA inserts. Replicate, independent biological samples were examined at each time point.
View Article and Find Full Text PDFThere is spontaneous cure of a large portion of Ascaris suum 4th-stage larvae (L4) from the jejunum of infected pigs between 14 and 21 days after inoculation (DAI). Those L4 that remain in the jejunum continue to develop while those that have moved to the ileum are eventually expelled from the intestines. Although increases in intestinal mucosal mast cells and changes in local host immunity are coincidental with spontaneous cure, the population of L4 that continue to develop in the jejunum may counteract host protective mechanisms by the differential production of factors related to parasitism.
View Article and Find Full Text PDF