Publications by authors named "Douglas A Johnson"

Discovery and analysis of genetic variants underlying agriculturally important traits are key to molecular breeding of crops. Reduced representation approaches have provided cost-efficient genotyping using next-generation sequencing. However, accurate genotype calling from next-generation sequencing data is challenging, particularly in polyploid species due to their genome complexity.

View Article and Find Full Text PDF
Article Synopsis
  • * Research in greenhouses revealed that controlling day length through supplemental lighting can synchronize flowering between certain Miscanthus and sugarcane genotypes, particularly those from low latitude regions.
  • * Experiments with 33 Miscanthus genotypes showed varying flowering responses based on day length, with low latitude variants generally flowering earlier under shorter days, while high latitude variants showed stunted growth and no flowering under short days.
View Article and Find Full Text PDF

Douglas A. Johnson began his career as a human rights activist while earning his undergraduate degree in philosophy (1975) at Macalester College in the United States. He lived at Gandhi's ashram in India to study nonviolent organizing (1969 to 1970).

View Article and Find Full Text PDF

Genetic analysis identifies multiple, potential protein binding sites important for insulator function in Arabidopsis thaliana: Rap1 site in UASrpg, Su(Hw) site in UASrpg, and CTCF site in BEAD1c. Three non-plant insulators UASrpg, BEAD1c, and gypsy isolated from Ashbya gossypii, Homo sapiens and Drosophila melanogaster gypsy retrotransposon, respectively, demonstrate insulator function in transgenic Arabidopsis thaliana. Here, the hypothesis that DNA sequences functional in A.

View Article and Find Full Text PDF

Background And Aims: Miscanthus, a C4 perennial grass native to East Asia, is a promising biomass crop. Miscanthus sacchariflorus has a broad geographic range, is used to produce paper in China and is one of the parents (along with Miscanthus sinensis) of the important biomass species Miscanthus × giganteus. The largest study of M.

View Article and Find Full Text PDF

Background and aims Miscanthus is a genus of perennial C4 grasses native to East Asia. It includes the emerging ligno-cellulosic biomass crop M. ×giganteus, a hybrid between M.

View Article and Find Full Text PDF

Cereal infection by the broad host range fungal pathogen Fusarium graminearum is a significant global agricultural and food safety issue due to the deposition of mycotoxins within infected grains. Methods to study the intracellular effects of mycotoxins often use the baker's yeast model system (Saccharomyces cerevisiae); however, this organism has an efficient drug export network known as the pleiotropic drug resistance (PDR) network, which consists of a family of multidrug exporters. This study describes the first study that has evaluated the potential involvement of all known or putative ATP-binding cassette (ABC) transporters from the PDR network in exporting the F.

View Article and Find Full Text PDF

The genus Elymus is a repository for a large number of species that have been difficult to classify by traditional techniques due to their remarkable levels of polymorphism. Following the genome analyses of Yen and Yang (Genus Elymus 5:58-362, 2013), we used sequences of the nr5SDNA to investigate diversity within those 24 species having St and H haplomes (Baum et al. Mol Genet Genomics 290:329-42, 2015) and for which the genome status was known.

View Article and Find Full Text PDF

Background: This study aimed to increase safety knowledge and behaviour of US Hispanic custodial workers in healthcare through a culturally appropriate training and monitoring process.

Method: A single-group, repeated-measures, pre-test and post-test design was used to examine training effectiveness across four sets of behaviours with 23 Spanish-speaking workers.

Results: Small group, lecture-style training in Spanish with pictures and video resulted in significant improvements in knowledge and behaviour.

View Article and Find Full Text PDF

The study of proportional relationships between size, shape, and function of part of or the whole organism is traditionally known as allometry. Examination of correlative changes in the size of interbranch distances (IBDs) at different root orders may help to identify root branching rules. Root morphological and functional characteristics in three range grasses {bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) Löve], crested wheatgrass [Agropyron desertorum (Fisch.

View Article and Find Full Text PDF

Elements that contribute to the high, stable yield of soybean peroxidase (SBP) in soybean seed coats can be exploited in the development of this tissue as a protein production platform. SBP contains an N-terminal and a C-terminal propeptide that are predicted to direct vacuolar targeting; this may be one factor that contributes to its high yield and stability. We characterized the function of the SBP propeptides and investigated their ability to increase the yield of a foreign protein in a heterologous plant system.

View Article and Find Full Text PDF

Objective: To study changes in bone mineral density (BMD) and a bone resorption marker in elderly men who received off-label zoledronic acid for osteoporosis treatment.

Methods: We conducted a retrospective review of medical records of 50 male veterans who had received at least one 4-mg intravenous infusion of zoledronic acid and had BMD measurements at 2 of 3 skeletal sites both before the infusion and at a mean of 2.2 years after the infusion.

View Article and Find Full Text PDF

To complete our study of the genus Hordeum and to elaborate a phylogeny of species based upon 5S rDNA sequences, we have cloned and sequenced PCR amplicons from seven American polyploid species to generate 164 new 5S rRNA gene sequences. These sequences were analysed along with the more than 2000 5S rDNA sequences previously generated from the majority of species in Hordeum to provide a comprehensive picture of the distribution (presence or absence) of 5S rDNA unit classes (orthologous groups) in this genus as well as insights into the phylogeny of Hordeum. Testing of substitution models for each unit class based upon the consensus sequences of all the taxa as well as for each unit class within the genus found that the general best fit was TPM3uf+G, from which a maximum-likelihood tree was calculated.

View Article and Find Full Text PDF

The expression pattern of tissue-specific promoters in transgenes can be influenced by promoter/enhancer elements employed for the expression of selectable marker genes or elements found in DNA flanking the insertion site. We have developed an analytical system in Arabidopsis thaliana to investigate strategies useful in blocking or reducing nonspecific interactions. These experiments confirm that the DNA configuration and the insertion of spacer DNA aid in the appropriate expression of tissue-specific promoters.

View Article and Find Full Text PDF

Exposure-based treatments have proven effective in treating a range of fears and phobias and can be accounted for by mechanisms described in behavioral theory. Enhanced dosed and dosed-only exposure are promising new behavioral approaches for treating fears and phobias. Thirty-nine participants with speech anxiety were randomly assigned to a prolonged exposure (PE) condition, a positively enhanced dosed exposure (PDE) condition, a dosed-only exposure (DE) condition, or a negatively-supplemented dosed exposure (NDE) condition.

View Article and Find Full Text PDF

A new genus Douglasdeweya containing the two species, Douglasdeweya deweyi and D. wangii was published in 2005 by Yen et al. based upon the results of cytogenetical and morphological findings.

View Article and Find Full Text PDF

A screen for genes involved in root nodule senescence has led to the isolation of the senescence-associated nodulin 1 (SAN1) multigene family from Glycine max (soybean). The three, tandemly repeated SAN1 genes each have three exons and two introns and are highly conserved. SAN1A and SAN1B code for conceptual proteins of 352 and 353 amino acids, respectively, and share over 83% sequence identity, while SAN1C encodes a truncated protein of 126 amino acids and is likely to be a pseudogene.

View Article and Find Full Text PDF

The molecular diversity of 5S rDNA from the closely related Asiatic diploid species, Hordeum bogdanii and the H. brevisubulatum complex has been catalogued and analysed. As in previous studies in Hordeum, we found that the sequences are constrained in such an manner that unit classes can be defined.

View Article and Find Full Text PDF

To facilitate detection of genotoxicity from environmental mutagen exposure, we generated an in vitro enhanced green fluorescence protein (EGFP) reactivation assay that quickly and effectively detects frameshift mutations in tandem repeat sequences (TRS). Two murine cell lines, C3H10T1/2 and mismatch repair deficient MC2a, were stably transfected with EGFP reporter plasmids in which the EGFP constructs contain TRS that put the EGFP sequence out of frame. These included several 2, 3, 4, 5 and 6 bp repeat sequences, a control non-repetitive sequence and a human gene sequence containing a 4 bp repeat motif.

View Article and Find Full Text PDF

5S rDNA clones from 12 South American diploid Hordeum species containing the HH genome and 3 Eurasian diploid Hordeum species containing the II genome, including the cultivated barley Hordeum vulgare, were sequenced and their sequence diversity was analyzed. The 374 sequenced clones were assigned to "unit classes", which were further assigned to haplomes. Each haplome contained 2 unit classes.

View Article and Find Full Text PDF

In biomaterials applications there exists a need to protect against the environmental release of recombinant microorganisms and transmissible genetic material and to prevent the recovery of proprietary genetic information. Irradiation technologies have long been used to eliminate microorganisms associated with spoilage and contamination and recent studies have demonstrated that moderate doses of irradiation may be used to sterilize medically important proteins without causing adverse effects in their desirable biological properties. Recombinant Escherichia coli cells expressing organophosphate hydrolase (OPH, E.

View Article and Find Full Text PDF

The extent of sequence identity among clones derived from monomorphic and polymorphic AFLPTM polymorphism bands was quantified. A total of 79 fragments from a monomorphic band of 273 bp and 48 fragments from a polymorphic band of 159 bp, isolated from individuals belonging to different populations, varieties, and species of Echinacea, were cloned and sequenced. The monomorphic fragments exhibited above 90% sequence identity among clones within samples.

View Article and Find Full Text PDF

We describe a gene, SCB1 (Seed Coat BURP-domain protein 1), that is expressed specifically within the soybean (Glycine max [L.] Merrill) seed coat early in its development. Northern blot analysis and mRNA in situ hybridization revealed novel patterns of gene expression during seed development.

View Article and Find Full Text PDF