A model system for studying plant-microbe interactions under snow.

A model plant–pathogen system using Arabidopsis and its natural snow mold pathogen demonstrated Arabidopsis plants develop disease resistance through cold acclimation.

Production of biologically active Atlantic salmon interferon in transgenic potato and rice plants.

Interferons (IFNs) are cytokines that induce an antiviral state in vertebrate cells. The Atlantic salmon (Salmo salar) IFN gene (SasaIFN-alpha1) was introduced in potato and rice plants by Agrobacterium-mediated transformation to produce a biologically active fish IFN in these plants. The transgenes and their transcripts were detected by PCR and Northern blot analysis.

Risk-managed production of bioactive recombinant proteins using a novel plant virus vector with a helper plant to complement viral systemic movement.

A plant viral vector has the potential to efficiently produce recombinant proteins at a low cost in a short period. Although recombinant proteins can be also produced by transgenic plants, a plant viral vector, if available, may be more convenient when urgent scale-up in production is needed. However, it is difficult to use a viral vector in open fields because of the risk of escape to the environment.

Ability of orally administered IFN-α4 to inhibit naturally occurring gingival inflammation in dogs.

It has been reported that type I interferons (IFN-α/β) play an important role in innate immune responses against viral and bacterial infections. In this study, we used and examined naturally occurred canine periodontal disease to show the therapeutic efficacy of low dose oral administration (LDOA) of canine IFN-α subtype 4 (CaIFN-α4). We administered purified recombinant CaIFN-α4 expressed in a baculovirus system to dogs with or without gingival inflammation.

Calditerricola satsumensis gen. nov., sp. nov. and Calditerricola yamamurae sp. nov., extreme thermophiles isolated from a high-temperature compost.

Two novel thermophilic micro-organisms, designated YMO81(T) and YMO722(T), were isolated from a high-temperature compost (internal temperature > 95 °C). The isolates were able to grow at 80 °C in a nutrient broth and in a synthetic medium. Cells were aerobic, Gram-negative rods (0.

The obligate alkaliphile Bacillus clarkii K24-1U retains extruded protons at the beginning of respiration.

Alkaliphiles grow under alkaline conditions that might be disadvantageous for the transmembrane pH gradient (Delta pH, outside acidic). In this study, the behaviors of extruded protons by the respiration of obligate alkaliphilic Bacillus clarkii K24-1U were investigated by comparison with those of neutralophilic Bacillus subtilis IAM 1026. Although whole-cell suspensions of both Bacillus species consumed oxygen immediately after the addition of air, there were lag times before the suspensions were acidified.

HC-Pro, a potyvirus RNA silencing suppressor, cancels cycling of Cucumber mosaic virus in Nicotiana benthamiana plants.

The mixed infection of Cucumber mosaic virus (CMV) and a potyvirus has been known to increase CMV titer in Nicotiana benthamiana plants, resulting in synergistic viral symptoms. We found that among three potyviruses--Potato virus Y (PVY), Turnip mosaic virus (TuMV), and Clover yellow vein virus (C1YVV)--synergistic effects on CMV (or a recombinant CMV vector) titers were most efficiently induced by a co-infection with PVY in N. benthamiana plants.

Crystal structure of salt-tolerant glutaminase from Micrococcus luteus K-3 in the presence and absence of its product L-glutamate and its activator Tris.

Glutaminase from Micrococcus luteus K-3 [Micrococcus glutaminase (Mglu); 456 amino acid residues (aa); 48 kDa] is a salt-tolerant enzyme. Our previous study determined the structure of its major 42-kDa fragment. Here, using new crystallization conditions, we determined the structures of the intact enzyme in the presence and absence of its product L-glutamate and its activator Tris, which activates the enzyme by sixfold.

Comparison of functional properties of two fungal antifreeze proteins from Antarctomyces psychrotrophicus and Typhula ishikariensis.

Antifreeze proteins are structurally diverse polypeptides that have thermal hysteresis activity and have been discovered in many cold-adapted organisms. Of these, fungal antifreeze protein has been purified and partially characterized only in a species of psychrophilic basidiomycete, Typhula ishikariensis. Here we report a new fungal antifreeze protein from another psychrophile, Antarctomyces psychrotrophicus.

Natural selection drives the fine-scale divergence of a coevolutionary arms race involving a long-mouthed weevil and its obligate host plant.

Background: One of the major recent advances in evolutionary biology is the recognition that evolutionary interactions between species are substantially differentiated among geographic populations. To date, several authors have revealed natural selection pressures mediating the geographically-divergent processes of coevolution. How local, then, is the geographic structuring of natural selection in coevolutionary systems?

Results: I examined the spatial scale of a "geographic selection mosaic," focusing on a system involving a seed-predatory insect, the camellia weevil (Curculio camelliae), and its host plant, the Japanese camellia (Camellia japonica).

Physiological role and redox properties of a small cytochrome c(5), cytochrome c-552, from alkaliphile, Pseudomonas alcaliphila AL15-21(T).

Cytochrome c-552 from Pseudomonas alcaliphila AL15-21(T), which is a small cytochrome c(5) from Pseudomonas spp., was first purified and characterized in our previous study. Although it has been found that cytochrome c-552 is induced at a high pH under air-limited condition, the physiological role of this cytochrome c has not been clarified yet.

Arabidopsis WUSCHEL is a bifunctional transcription factor that acts as a repressor in stem cell regulation and as an activator in floral patterning.

Most transcription factors act either as activators or repressors, and no such factors with dual function have been unequivocally identified and characterized in plants. We demonstrate here that the Arabidopsis thaliana protein WUSCHEL (WUS), which regulates the maintenance of stem cell populations in shoot meristems, is a bifunctional transcription factor that acts mainly as a repressor but becomes an activator when involved in the regulation of the AGAMOUS (AG) gene. We show that the WUS box, which is conserved among WOX genes, is the domain that is essential for all the activities of WUS, namely, for regulation of stem cell identity and size of floral meristem.

Arabidopsis SBP-box genes SPL10, SPL11 and SPL2 control morphological change in association with shoot maturation in the reproductive phase.

Lateral organ traits in higher plants, such as lamina shape and trichome distribution, change gradually in association with shoot maturation. Regulation of this shoot maturation process in the vegetative phase has been extensively investigated, and members of the SQUAMOSA PROMOTER BINDING PROTEIN (SBP)-box family of transcription factors have been shown to be involved in this process. However, little is known about the regulation of shoot maturation in the reproductive phase.

Construction of highly reactive probes for abasic site detection by introduction of an aromatic and a guanidine residue into an aminooxy group.

Abasic sites (AP sites) arise from hydrolysis of glycosidic bonds of DNA that is damaged by various external and internal processes; unrepaired AP sites give rise to genetic mutations. We have constructed highly reactive AP-site-detecting probes by introducing a hydrophobic and a hydrophilic residue in an aminooxy group. Synthesized probes containing either a naphthalene or a guanidine residue conjugate effectively with AP sites.

Development of novel chemical probes to detect abasic sites in DNA.

We chemically synthesized a series of aminooxy derivatives to develop novel probes for sensitive detection of abasic (AP) sites in DNA. The results of the conjugation reactions showed that the probes could efficiently react to AP sites by introducing an aromatic or a guanidino group in their structures. In particular, the probe having both functional groups showed the most effective reactivity, indicating that hydrophobic and electrostatic interactions cooperatively acted in the reaction of the probe to AP sites.

Do arms races punctuate evolutionary stasis? Unified insights from phylogeny, phylogeography and microevolutionary processes.

One of the major controversies in evolutionary biology concerns the processes underlying macroevolutionary patterns in which prolonged stasis is disrupted by rapid, short-term evolution that leads species to new adaptive zones. Recent advances in the understanding of contemporary evolution have suggested that such rapid evolution can occur in the wild as a result of environmental changes. Here, we examined a novel hypothesis that evolutionary stasis is punctuated by co-evolutionary arms races, which continuously alter adaptive peaks and landscapes.

Psychrobacter piscatorii sp. nov., a psychrotolerant bacterium exhibiting high catalase activity isolated from an oxidative environment.

A Gram-negative, non-motile, psychrotolerant bacterium exhibiting high catalase activity, designated strain T-3-2(T), was isolated from a drain of a fish-processing plant. Its catalase activity was 12 000 U (mg protein)(-1), much higher than the activity of the other Psychrobacter strains tested. The strain grew at 0-30 degrees C and in the presence of 0-12 % NaCl.

Paenibacillus macquariensis subsp. defensor subsp. nov., isolated from boreal soil.

Two Gram-variable, aerobic, motile, rod-shaped, endospore-forming bacterial strains, M4-2T and M4-1, were isolated from soil samples collected from Oblast Magadan, Russian Far East, as micro-organisms antagonistic to the psychrophilic phytopathogenic fungus Typhula ishikariensis. Strains M4-2T and M4-1 were identified as members of the genus Paenibacillus by phenotypic and phylogenetic analyses based on 16S rRNA gene sequences. The strains contained anteiso-C15:0 as the major fatty acid (63.

Construction of time-lapse scanning electrochemical microscopy with temperature control and its application to evaluate the preservation effects of antifreeze proteins on living cells.

Antifreeze proteins (AFPs) can protect cells from hypothermic damage; however, their mechanism of action remains unclear. Scanning electrochemical microscopy (SECM) can evaluate the size and activities of cells, although long-term continuous monitoring has been unsuccessful. We constructed a novel, fully automated, time-lapse SECM system and investigated the cell preservation effect of AFPs by analyzing single cellular topography at low temperatures.

Conditional gene silencing of multiple genes with antisense RNAs and generation of a mutator strain of Escherichia coli.

In this study, we describe a method of simultaneous conditional gene silencing of up to four genes in Escherichia coli by using antisense RNAs. We used antisense RNAs with paired termini, which carried flanking inverted repeats to create paired double-stranded RNA termini; these RNAs have been proven to have high silencing efficacy. To express antisense RNAs, we constructed four IPTG-inducible vectors carrying different but compatible replication origins.

A chimeric NST repressor has the potential to improve glucose productivity from plant cell walls.

Bioethanol might be produced more economically and with less ecological impact (with reduced exploitation of food crops) if we could increase the production of glucose from the cellulosic materials in plant cell walls. However, plant cell walls are relatively resistant to enzymatic and physicochemical hydrolysis and, therefore, it is necessary to develop methods for reducing such resistance. Changes in plant cell wall materials, by genetic engineering, that render them more easily hydrolyzable to glucose might be a valuable approach to this problem.

Functional analysis of transcription factors in Arabidopsis.

Transcription factors (TFs) regulate the expression of genes at the transcriptional level. Modification of TF activity dynamically alters the transcriptome, which leads to metabolic and phenotypic changes. Thus, functional analysis of TFs using 'omics-based' methodologies is one of the most important areas of the post-genome era.