Purdue University

About: Purdue University is a education organization based out in West Lafayette, Indiana, United States. It is known for research contribution in the topics: Population & Heat transfer. The organization has 73219 authors who have published 163563 publications receiving 5775236 citations. The organization is also known as: Purdue & Purdue-West Lafayette.

Identification and characterization of MPG1, a gene involved in pathogenicity from the rice blast fungus Magnaporthe grisea.

Abstract: Differential cDNA cloning was used to identify genes expressed during infectious growth of the fungal pathogen Magnaporthe grisea in its host, the rice plant. We characterized one of these genes, MPG1, in detail. Using a novel assay to determine the proportion of fungal biomass present in the plant, we determined that the MPG1 transcript was 60-fold more abundant during growth in the plant than in culture. Mpg1 mutants have a reduced ability to cause disease symptoms that appears to result from an impaired ability to undergo appressorium formation. MPG1 mRNA was highly abundant very early in plant infection concomitant with appressorium formation and was also abundant at the time of symptom development. The MPG1 mRNA was also expressed during conidiation and in mycelial cultures starved for nitrogen or carbon. MPG1 potentially encodes a small, secreted, cysteine-rich, moderately hydrophobic protein with the characteristics of a fungal hydrophobin. Consistent with the role of the MPG1 gene product as a hydrophobin, Mpg1 mutants show an "easily wettable" phenotype. Our results suggest that hydrophobins may have a role in the elaboration of infective structures by fungi and may fulfill other functions in fungal phytopathogenesis.

Primary structural comparison of RNA-dependent polymerases from plant, animal and bacterial viruses.

Abstract: Possible alignments for portions of the genomic codons in eight different plant and animal viruses are presented: tobacco mosaic, brome mosaic, alfalfa mosaic, sindbis, foot-and-mouth disease, polio, encephalomyocarditis, and cowpea mosaic viruses. Since in one of the viruses (polio) the aligned sequence has been identified as an RNA-dependent polymerase, this would imply the identification of the polymerases in the other viruses. A conserved fourteen-residue segment consisting of an Asp-Asp sequence flanked by hydrophobic residues has also been found in retroviral reverse transcriptases, a bacteriophage, influenza virus, cauliflower mosaic virus and hepatitis B virus, suggesting this span as a possible active site or nucleic acid recognition region for the polymerases. Evolutionary implications are discussed.

The influence of irrelevant location information on performance: A review of the Simon and spatial Stroop effects

Abstract: The purpose of this paper is to investigate the effect of irrelevant location information on performance of visual choice-reaction tasks. We review empirical findings and theoretical explanations from two domains, those of the Simon effect and the spatial Stroop effect, in which stimulus location has been shown to affect reaction time when irrelevant to the task. We then integrate the findings and explanations from the two domains to clarify how and why stimulus location influences performance even when it is uninformative to the correct response. Factors that influence the processing of irrelevant location information include response modality, relative timing with respect to the relevant information, spatial coding, and allocation of attention. The most promising accounts are offered by models in which response selection is a function of (1) strength of association of the irrelevant stimulus information with the response and (2) temporal overlap of the resulting response activation with that produced by the relevant stimulus information.