Evaluation of the allergenicity of ω5-gliadin-deficient Hokushin wheat (1BS-18) in a wheat allergy rat model

We previously developed Hokushin wheat line as a hypoallergenic wheat lacking ω5-gliadin (1BS-18), a major allergen for wheat-dependent exercise-induced anaphylaxis. However, the allergenicity of 1BS-18 has not been understood completely. In this study, we evaluated the allergenicity of 1BS-18 such as anaphylactic elicitation ability and sensitization ability using rats sensitized with ω5-gliadin or glutens prepared from Hokushin (Hokushin gluten) or 1BS-18 (1BS-18 gluten). Rats were sensitized by intraperitoneal administration of ω5-gliadin, Hokushin gluten or 1BS-18 gluten. Immunoglobulin E-mediated systemic anaphylaxis was evaluated by measuring changes in rectal temperature for 30 min after intravenous challenge with ω5-gliadin or the test glutens in unsensitized rats or rats sensitized with ω5-gliadin or the test glutens. In ω5-gliadin-sensitized rats, intravenous challenge with ω5-gliadin or Hokushin gluten significantly decreased the rectal temperature at 30 min after challenge while challenge with 1BS-18 gluten did not reduce the rectal temperature. Furthermore, intravenous challenge with ω5-gliadin significantly decreased the rectal temperature in rats sensitized with Hokushin gluten or 1BS-18 gluten. However, the reduced degree observed in 1BS-18 gluten-sensitized rats was smaller than that in Hokushin gluten-sensitized rats. In conclusion, 1BS-18 elicited no allergic reaction in ω5-gliadin-sensitized rats and had less sensitization ability for ω5-gliadin than that of Hokushin wheat.     

The antioxidative function of eicosapentaenoic acid in a marine bacterium, Shewanella marinintestina IK-1

When the eicosapentaenoic acid (EPA)-deficient mutant strain IK-1Delta8 of the marine EPA-producing Shewanella marinintestina IK-1 was treated with various concentrations of hydrogen peroxide (H(2)O(2)), its colony-forming ability decreased more than that of the wild type. Protein carbonylation, induced by treating cells with 0.01 mM H(2)O(2) under bacteriostatic conditions, was enhanced only in cells lacking EPA. The amount of cells recovered from the cultures was decreased more significantly by the presence of H(2)O(2) for cells lacking EPA than for those producing EPA. Treatment of the cells with 0.1 mM H(2)O(2) resulted in much lower intracellular concentrations of H(2)O(2) being consistently detected in cells with EPA than in those without EPA. These results suggest that cellular EPA can directly protect cells against oxidative damage by shielding the entry of exogenously added H(2)O(2) in S. marinintestina IK-1.     

Legumain/asparaginyl endopeptidase controls extracellular matrix remodeling through the degradation of fibronectin in mouse renal proximal tubular cells

Legumain/asparaginyl endopeptidase (EC 3.4.22.34) is a novel cysteine protease that is abundantly expressed in the late endosomes and lysosomes of renal proximal tubular cells. Recently, emerging evidence has indicated that legumain might play an important role in control of extracellular matrix turnover in various pathological conditions such as tumor growth/metastasis and progression of atherosclerosis. We initially found that purified legumain can directly degrade fibronectin, one of the main components of the extracellular matrix, in vitro. Therefore, we examined the effect of legumain on fibronectin degradation in cultured mouse renal proximal tubular cells. Fibronectin processing can be inhibited by chloroquine, an inhibitor of lysosomal degradation, and can be enhanced by the overexpression of legumain, indicating that fibronectin degradation occurs in the presence of legumain in lysosomes from renal proximal tubular cells. Furthermore, in legumain-deficient mice, unilateral ureteral obstruction (UUO)-induced renal interstitial protein accumulation of fibronectin and renal interstitial fibrosis were markedly enhanced. These findings indicate that legumain might have an important role in extracellular matrix remodeling via the degradation of fibronectin in renal proximal tubular cells.     

Identification and characterization of plasma kallikrein-kinin system inhibitors from salivary glands of the blood-sucking insect Triatoma infestans

Two plasma kallikrein-kinin system inhibitors in the salivary glands of the kissing bug Triatoma infestans, designated triafestin-1 and triafestin-2, have been identified and characterized. Reconstitution experiments showed that triafestin-1 and triafestin-2 inhibit the activation of the kallikrein-kinin system by inhibiting the reciprocal activation of factor XII and prekallikrein, and subsequent release of bradykinin. Binding analyses showed that triafestin-1 and triafestin-2 specifically interact with factor XII and high molecular weight kininogen in a Zn2+-dependent manner, suggesting that they specifically recognize Zn2+-induced conformational changes in factor XII and high molecular weight kininogen. Triafestin-1 and triafestin-2 also inhibit factor XII and high molecular weight kininogen binding to negatively charged surfaces. Furthermore, they interact with both the N-terminus of factor XII and domain D5 of high molecular weight kininogen, which are the binding domains for biological activating surfaces. These results suggest that triafestin-1 and triafestin-2 inhibit activation of the kallikrein-kinin system by interfering with the association of factor XII and high molecular weight kininogen with biological activating surfaces, resulting in the inhibition of bradykinin release in an animal host during insect blood-feeding.     

No apparent effects of the buccal cavity attaching parasite,Salmincola sp. (Copepoda: Lernaeopodidae), on a stream salmonid: a mark-recapture study

Ichthyological Research - We evaluated the effects of a buccal cavity attaching Salmincola sp. on white-spotted charr Salvelinus leucomaenis by mark-recapture method to compare body condition,...     

Construction of a Pseudozyma antarctica strain without foreign DNA sequences (self-cloning strain) for high yield production of a biodegradable plastic-degrading enzyme

ABSTRACT

The basidiomycetous yeast Pseudozyma antarctica GB-4(0) esterase (PaE) is a promising candidate for accelerating degradation of used biodegradable plastics (BPs). To increase safety and reduce costs associated with the use of PaE, we constructed a self-cloning strain with high-PaE productivity. A Lys12 gene (PaLYS12)-deleted lysine auxotroph strain GB4-(0)-L1 was obtained from GB-4(0) by ultraviolet mutagenesis and nystatin enrichment. Subsequently, the PaE gene (PaCLE1) expression cassette consisting of GB-4(0)-derived PaCLE1, under the control of a xylose-inducible xylanase promoter with PaLYS12, was randomly introduced into the GB4-(0)-L1 genome. A PaE high-producing strain, PGB474, was selected from among the transformants by high throughput double-screening based on its ability to degrade emulsified polybutylene succinate-co-adipate. Quantitative PCR revealed that four copies of the PaE gene expression cassette were introduced into the PGB474 genome. PGB474 produced 2.0 g/L of PaE by xylose-fed-batch cultivation using a 3-L jar fermentor for 72 h.     

Fern gametophytes of Angiopteris lygodiifolia and Osmunda japonica harbor diverse Mucoromycotina fungi

Journal of Plant Research - Mycorrhizal symbiosis between plants and fungi is ubiquitous, and has been played key roles in plant terrestrialization and diversification. Although arbuscular...     

Effects of cytoskeleton-disrupting agents on tyrosine transport into cultured bovine adrenal chromaffin cells

The effects of various cytoskeleton-disrupting agents on tyrosine transport into chromaffin cells were examined to assess the possibility of cytoskeleton involvement in the regulation of precursor supply for catecholamine synthesis. Tyrosine transport was markedly increased by cytochalasin B. Vinblastine also stimulated tyrosine transport, although its effect was less pronounced than that of cytochalasin B. While colchicine failed to cause any significant increase in the transport under the same conditions. These results therefore suggest a possible role of microfilaments as a factor regulating tyrosine transport into chromaffin cells.     

A method for micrometer resolution patterning of primary culture neurons for SPM analysis

In this work we present a method for ultra-fine patterning of primary culture neuron cell growth, which is compatible for scanning near-field optical atomic force microscopy (SNOAM) analysis. SNOAM uses near-field optics to break the fundamental diffraction limit imposed on normal microscopy. SNOAM can achieve sub-100 nm optical resolutions, but requires transparent, open substrates. The ability to do physiological measurements on patterns of neurons, combined with ultra high resolution optical and fluorescent analysis, is useful in the study of long-term potentiation. The patterning method consists of chemical guidance with an element of physical confinement and allows for ultra-fine patterning of neural growth on transparent glass substrates. Substrates consist of microfabricated perfluoropolymer barrier structures on glass. Poly-L-lysine was selectively deposited using a silicone-based microfluidic stencil aligned to the perfluoropolymer/glass substrate. Primary culture neurons were extracted from 8-day-old chicks and grown for 3 days to form good networks. This patterning system shows very specific growth with patterning separations down to the level of individual neurites. Fluorescent imaging was carried out on both cell viability during growth and immuno-tagged microtubule-associated proteins on the neurites. Neurons inside the patterned structures were imaged and analyzed with a tapping mode SNOAM.