Analyses of leaves from open field-grown transgenic poplars overexpressing xyloglucanase

The transgenic expression of Aspergillus xyloglucanase cDNA (AaXEG2) with 35S promoter in the leaves of open field-grown poplars was studied. The level of xyloglucan in the transgenic poplars was decreased to 15–16% in the non-fertile soil (forest-field soil) and to 21–22% in the fertile soil (farming-field soil) compared with that of the wild-type poplars. The leaves exhibited a smaller surface area with more rounded teeth than those of the wild-type plants, similar to the sun leaf variety that was grown in the incubation room and subsequently greenhoused. The majority of total veins with water-conducting vascular bundles were shorter in the leaves of the transgenic poplars than those of the wild type. This decrease in vein length may result from a decrease in xyloglucan during leaf development, from which large numbers of proteins were markedly downregulated in the leaves of the transgenic plants via proteomic analysis. It seems likely that the leaves of the transgenic poplars came to relax the edges of their tooth rather than extend their veins as a result of the loosening of the xyloglucan cellulose networks in the leaves.     

An enzyme-linked immunosorbent assay using nuclear antigen for detection of feline herpesvirus 1 antibody.

To detect antibody against feline herpesvirus 1 (FHV-1) in the sera of cats, the sensitivity and specificity of an enzyme-linked immunosorbent assay (ELISA) using nuclear antigen was investigated. The standardized optical density readings (ODs) of the ELISA obtained by the 1-step serum dilution (1:80) method were compared with the serum neutralization test (SNT) results, with a correlation of 0.993, and with the hemagglutination inhibition (HI) test results, with a correlation of 0.851. The ODs for the ELISA titers were obtained using the serial serum dilution method and were compared with the SNT results, with a correlation of 0.933, and with the HI test results, with a correlation of 0.987. In the experimental infection of 4 specific-pathogen-free cats, the results of different serologic tests (SNT and HI) and the ELISA using the serial serum dilution method revealed rapid production of antibodies after inoculation, whereas the ELISA using the one-step serum dilution method indicated that titers increased more slowly. These results indicate that with the present ELISA using nuclear antigen, there are fewer demands on time and labor, making the method convenient for monitoring FHV-1 infection.     

Cold acclimation and photoinhibition of photosynthesis accompanied by needle color changes inCryptomeria japonica during the winter

This study focused on the physiological changes inCryptomeria japonica accompanied by needle color changes during the winter. The physiological measurements include gas exchange, chlorophyll fluorescence, pigments, active oxygen scavenging enzymes, and several proteins in the photosynthetic apparatus. The light-saturated photosynthesis decreased during the winter. Total chlorophyll content and chlorophylla/b ratio decreased; meanwhile xanthophyll cycle pigments and lutein contents increased significantly. These results indicate that cold acclimation had occurred. Photoinhibition was also observed inC. japonica which can be determined from the decreases in photochemical efficiency of PS II and the partial closure of PS II reaction centers. Small and large subunits of Rubisco and LHC II in the needles ofC. japonica showed only a slight decrease during the winter, indicating that photoinhibition inC. japonica probably reflects a protective process to prevent more severe damage to the photosynthetic apparatus during low-temperature stress. This research was supported by the Bio-oriented Technology Research Advancement Institute (BRAIN), Japan     

Mammary lesions associated with bovine herpesvirus type 4 in a cow with clinical mastitis

Intranuclear eosinophilic inclusion bodies were seen in the lactiferous duct and sinus epithelium of mammary tissues collected from a cow with clinical mastitis. Transmission electron microscopy revealed herpesvirus particles in these cells. Immunolabeling against anti bovine herpesvirus type 4 (BHV-4) rabbit serum was detected in nuclei that had intranuclear inclusion bodies. In addition, BHV-4 was isolated from the mammary tissue. The viral DNA was detected by nested PCR from the same tissue. This is the first report to describe mammary lesions in association with BHV-4.     

Requirement for the SLP-76 adaptor GADS in T cell development

GADS is an adaptor protein implicated in CD3 signaling because of its ability to link SLP-76 to LAT. A GADS-deficient mouse was generated by gene targeting, and the function of GADS in T cell development and activation was examined. GADS- CD4-CD8- thymocytes exhibited a severe block in proliferation but still differentiated into mature T cells. GADS- thymocytes failed to respond to CD3 cross-linking in vivo and were impaired in positive and negative selection. Immunoprecipitation experiments revealed that the association between SLP-76 and LAT was uncoupled in GADS- thymocytes. These observations indicate that GADS is a critical adaptor for CD3 signaling.     

Simple detection method of powerful antiradical compounds in the raw extract of plants and its application for the identification of antiradical plant constituents

A simple detection method for a powerful radical scavenging compound in a mixture containing a large variety of compounds, such as the raw extract of edible plants, was developed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) as the radical reagent. The method was established on the basis of the features of the typical chain-breaking antioxidation reaction mechanism, which suggests that the radical scavenging antioxidant should be converted to other stable nonradical compounds during the reaction. This method requires only a simple HPLC instrument, and the disappearance or decrease in the peak intensity, which is induced by the addition of DPPH. This change is monitored by the HPLC to detect the powerful radical scavenger from the complex mixture. The method was applied to the detection and identification of the most powerful antiradical compound in the extracts of three antioxidatively active plant extracts (Psidium guajava, Citrus depressa, and Hypericum chinense). The radical scavenging efficiency of a newly identified compound from H. chinense was also compared with that of Trolox and catechin using the method.     

Recovery mechanism of the antioxidant activity from carnosic acid quinone,an oxidized sage and rosemary antioxidant

A solution of carnosic acid quinone, which is a radical chain-termination product having no antioxidant activity in the antioxidant reaction of carnosic acid, recovers potent antioxidant activity upon standing. The HPLC analysis of an aged solution of carnosic acid quinone revealed that several antioxidants are produced in the solution. From the time-course and quantitative analyses of the formation of the products and their structural analysis, an antioxidant mechanism from carnosic acid quinone is proposed that includes a redox reaction of carnosic acid quinone in addition to the isomerization to lactone derivatives. In the first stage of antioxidation, carnosic acid, the reduction product from carnosic acid quinone, contributes to the potent antioxidant activity of the solution. This proposed mechanism can explain one of the reasons for the strong antioxidant activity of the extract of the popular herbs sage and rosemary.