A5079312266- Plant-Microbe Interactions and Immunity
- Plant tissue culture and regeneration
- Plant Gene Expression Analysis
- Plant pathogens and resistance mechanisms
- Plant Virus Research Studies
- Plant Pathogenic Bacteria Studies
- Plant Molecular Biology Research
- Transgenic Plants and Applications
- Legume Nitrogen Fixing Symbiosis
- Photosynthetic Processes and Mechanisms
- Plant Stress Responses and Tolerance
- Plant biochemistry and biosynthesis
- Plant Reproductive Biology
- Plant Pathogens and Fungal Diseases
- Genomics, phytochemicals, and oxidative stress
- Plant Genetic and Mutation Studies
- Hemoglobin structure and function
- Polysaccharides and Plant Cell Walls
- Biofuel production and bioconversion
- Nematode management and characterization studies
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Biochemical and biochemical processes
- Plant Parasitism and Resistance
- Biochemical and Structural Characterization
- Nitric Oxide and Endothelin Effects
Keck Hospital of USC
2024-2025
Newcastle University
2024
Jacksonville College
2024
Mayo Clinic in Florida
2024
WinnMed
2024
VA Greater Los Angeles Healthcare System
2023
Mayo Clinic in Arizona
2022
Newcastle upon Tyne Hospitals NHS Foundation Trust
2021
University of California, Los Angeles
2021
John Innes Centre
2002-2012
Rapid generation of superoxide and accumulation H2O2 is a characteristic early feature the hypersensitive response following perception pathogen avirulence signals. Emerging data indicate that oxidative burst reflects activation membrane-bound NADPH oxidase closely resembling operating in activated neutrophils. The oxidants are not only direct protective agents, but also functions as substrate for cross-linking cell wall, threshold trigger death, diffusible signal induction cellular...
Plants produce a wide array of natural products, many which are likely to be useful bioactive structures. Unfortunately, these complex products usually occur at very low abundance and with restricted tissue distribution, thereby hindering their evaluation. Here, we report novel approach for enhancing the accumulation based on activation tagging by Agrobacterium-mediated transformation T-DNA that carries cauliflower mosaic virus 35S enhancer sequences its right border. Among ∼5000 Arabidopsis...
Nitric oxide (NO) and reactive oxygen intermediates (ROIs) play key roles in the activation of disease resistance mechanisms both animals plants. In NO cooperates with ROIs to kill tumor cells for macrophage killing bacteria. Such cytotoxic events occur because unregulated levels drive a diffusion-limited reaction O 2 − generate peroxynitrite (ONOO ), mediator cellular injury many biological systems. Here we show that soybean production at onset pathogen-induced hypersensitive response (HR)...
Activation tagging using T-DNA vectors that contain multimerized transcriptional enhancers from the cauliflower mosaic virus (CaMV) 35S gene has been applied to Arabidopsis plants. New activation-tagging confer resistance antibiotic kanamycin or herbicide glufosinate have used generate several tens of thousands transformed From these, over 30 dominant mutants with various phenotypes isolated. Analysis a subset shown overexpressed genes are almost always found immediately adjacent inserted...
Programmed cell death (PCD) is a physiological process involved in the selective elimination of unwanted cells (Ellis et al., 1991). In animals, these include those that have served temporary functions, such as tadpole tail at metamorphosis; are overproduced, vertebrate neurons; or present inappropriate positions, between developing digits and Mullerian duct required females but not males; die during specialization, keratinocytes surface skin (Jacobsen 1997). PCD specific types can also give...
Rapid generation of O2- and H2O2, which is reminiscent the oxidative burst in neutrophils, a central component resistance response plants to pathogen challenge. Here, we report that Arabidopsis rbohA (for respiratory oxidase homolog A) gene encodes putative 108-kD protein, with C-terminal region shows pronounced similarity 69-kD apoprotein gp91phox subunit neutrophil NADPH oxidase. The RbohA protein has large hydrophilic N-terminal domain not present gp91phox. This contains two Ca2+ binding...
Elicitation of soybean cells causes a rapid insolubilization two cell wall structural proteins, p33 and p100. Likewise, short elicitation 30 min rendered walls more refractory to enzyme digestion as assayed by the yield protoplasts released. This effect could be ascribed protein cross-linking because its insensitivity inhibitors transcription (actinomycin D) translation (cycloheximide) induction exogenous H2O2. Moreover, induced loss prevented preincubation with DTT, which also blocks...
The phenylpropanoid-derived natural product salicylic acid (SA) plays a key role in disease resistance. However, SA administered the absence of pathogen is paradoxically weak inductive signal, often requiring concentrations 0.5 to 5 mM induce acquired resistance or related defense mechanisms precondition signal systems. In contrast, endogenous accumulates < 70 microM at site attempted infection. Here, we show that although 10 100 had negligible effects when soybean cell suspensions pathogen,...
An assay was developed to study plant receptor kinase activation and signaling mechanisms. The extracellular leucine-rich repeat (LRR) transmembrane domains of the Arabidopsis BRI1, which is implicated in brassinosteroid signaling, were fused serine/threonine domain XA21, rice disease resistance receptor. chimeric initiates defense responses cells upon treatment with brassinosteroids. These results, indicate that BRI1 perceives brassinosteroids, suggest a general mechanism for LRR kinases...
Microbial elicitors or attempted infection with an avirulent pathogen strain causes the rapid production of reactive oxygen intermediates. Recent findings indicate that H2O2 from this oxidative burst plays a central role in orchestration hypersensitive response: (i) as substrate driving cross-linking cell wall structural proteins to slow microbial ingress prior deployment transcription-dependent defenses and trap pathogens cells destined undergo death, (ii) local threshold trigger programmed...
Activation of plant defense genes was investigated by analysis transcripts completed in vitro isolated nuclei. Elicitor treatment suspension-cultured bean (Phaseolus vulgaris L.) cells caused marked transient stimulation transcription encoding apoproteins cell wall hydroxyproline-rich glycoproteins (HRGP) and the phenylpropanoid biosynthetic enzymes phenylalanine ammonia-lyase (PAL) chalcone synthase (CHS), concomitant with onset rapid accumulation respective mRNAs hence expression...
We isolated an activation-tagged Arabidopsis (Arabidopsis thaliana) line, constitutive disease susceptibility2-1D (cds2-1D), that showed enhanced bacterial growth when challenged with various Pseudomonas syringae strains. Systemic acquired resistance and systemic PATHOGENESIS-RELATED GENE1 induction were also compromised in cds2-1D. The T-DNA insertion adjacent to NINE-CIS-EPOXYCAROTENOID DIOXYGENASE5 (NCED5), one of six genes encoding the abscisic acid (ABA) biosynthetic enzyme NCED, caused...
Nitric oxide (NO) is a widespread signaling molecule, and numerous targets of its action exist in plants. Whereas the activity NO erythrocytes, microorganisms, invertebrates has been shown to be regulated by several hemoglobins, function plant hemoglobins detoxification not yet elucidated. Here, we show that Arabidopsis thaliana nonsymbiotic hemoglobin AHb1 scavenges through production S-nitrosohemoglobin reduces emission under hypoxic stress, indicating role detoxification. However, does...
Phenylalanine ammonia-lyase (PAL) catalyzes the first step in phenylpropanoid synthesis. The role of PAL pathway regulation was investigated by measurement product accumulation as a function enzyme activity collection near-isogenic transgenic tobacco plants exhibiting range levels from wild type to 0.2% type. In leaf tissue, level is dominant factor regulating major chlorogenic acid and overall flux into pathway. stems, at wild-type contributes, together with downstream steps, lignin...
We analyzed lignin content and composition in transgenic tobacco (Nicotiana tabacum) lines altered the expression of early phenylpropanoid biosynthetic enzymes L-phenylalanine ammonia-lyase cinnamate 4-hydroxylase (C4H). The reduction C4H activity by antisense or sense suppression resulted reduced levels Klason lignin, accompanied a decreased syringyl/guaiacyl monomer ratio as determined pyrolysis gas chromatography/mass spectrometry Similar down -regulation ammonia-lyase, enzyme preceding...
Hydroxyproline-rich glycoproteins (HRGPs) are important structural components of plant cell walls and also accumulate in response to infection as an apparent defense mechanism. Accumulation HRGP mRNA biologically stressed bean (Phaseolus vulgaris L.) cells was monitored by blot hybridization with (32)P-labeled tomato genomic sequences. Elicitor treatment suspension-cultured caused a marked increase hybridizable mRNA. The less rapid but more prolonged than that observed for mRNAs encoding...