Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Entire DC Network
Mutations In Pmr5 Result In Powdery Mildew Resistance And Altered Cell Wall Composition, John P. Vogel, Ted K. Raab, Chris R. Somerville, Shauna C. Somerville
Mutations In Pmr5 Result In Powdery Mildew Resistance And Altered Cell Wall Composition, John P. Vogel, Ted K. Raab, Chris R. Somerville, Shauna C. Somerville
Ted K. Raab
Powdery mildews and other obligate biotrophic pathogens are highly adapted to their hosts and often show limited host ranges. One facet of such host specialization is likely to be penetration of the host cell wall, a major barrier to infection. A mutation in the pmr5 gene rendered Arabidopsis resistant to the powdery mildew species Erysiphe cichoracearum and Erysiphe orontii, but not to the unrelated pathogens Pseudomonas syringae or Peronospora parasitica. PMR5 belongs to a large family of plant-specific genes of unknown function. pmr5-mediated resistance did not require signaling through either the salicylic acid or jasmonic acid/ ethylene defense pathways, suggesting …
Ecological And Agricultural Applications Of Synchrotron Ir Microscopy, Ted K. Raab, John P. Vogel
Ecological And Agricultural Applications Of Synchrotron Ir Microscopy, Ted K. Raab, John P. Vogel
Ted K. Raab
The diffraction-limited spot size of synchrotron-based IR microscopes provides cell-specific, spectrochemical imaging of cleared leaf, stem and root tissues of the model genetic organism Arabidopsis thaliana, and mutant plants created either by T-DNA insertional inactivation or chemical mutagenesis. Spectra in the wavelength region from 6 to 12 microns provide chemical and physical information on the cell wall polysaccharides of mutants lacking particular biosynthetic enzymes (‘‘Cellulose synthase-like’’ genes). In parallel experiments, synchrotron IR microscopy delineates the role of Arabidopsis cell wall enzymes as susceptibility factors to the fungus Erysiphe cichoracearum, a causative agent of powdery mildew disease. Three genes, pmr4, pmr5, …
Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville
Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville
Ted K. Raab
The plant genes required for the growth and reproduction of plant pathogens are largely unknown. In an effort to identify these genes, we isolated Arabidopsis mutants that do not support the normal growth of the powdery mildew pathogen Erysiphe cichoracearum. Here, we report on the cloning and characterization of one of these genes, PMR6. PMR6 encodes a pectate lyase-like protein with a novel C-terminal domain. Consistent with its predicted gene function, mutations in PMR6 alter the composition of the plant cell wall, as shown by Fourier transform infrared spectroscopy. pmr6-mediated resistance requires neither salicylic acid nor the ability to perceive …
Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin
Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin
Ted K. Raab
A bright synchrotron light source operated by the Lawrence Berkeley National Laboratory served as an external source for infrared (IR) microscopy of plant root microcosms. Mid-IR light from synchrotrons is 2-3 orders of magnitude brighter than conventional sources, providing contrast based on the chemical information in the reflected signal at a spatial resolution near the diffraction-limit of 3-10 microns. In an experiment using plant root microcosms fitted with zinc selenide IR-transmissive windows (50 mm x 20 mm x 1 mm), we describe chemical differences and similarities within the root zone of mung bean (Vigna radiata L.), grown with or without …