Gene Expression Profile of Hemocytes of Kuruma Shrimp, Marsupenaeus japonicus Following Peptidoglycan Stimulation

Shrimps are believed to lack an adaptive immune system and therefore rely heavily on their innate immune mechanisms to ward off pathogens. Moreover, their innate defense reactions are triggered by bacterial and fungal cell wall components such as lipopolysaccharides, peptidoglycan and β-glucans. In this study, we used microarray to examine the gene expression profile of kuruma shrimp, Marsupenaeus japonicus, after stimulation with peptidoglycan. Subsequent results show that the number of upregulated genes and percentage of differential expression (21%) was highest at day 1 poststimulation. Differentially expressed genes in day 7 and day 14, on the other hand, were 3.25% and 11.21%, respectively. Sixty-one (61) genes of unknown function were found to have responded outright to peptidoglycan (PG) stimulation. Administration of PG also caused increases in the expressions of crustin, lysozyme, and a few antibacterial peptides, all of which are known to be involved in crustacean immune response. Taken together, our results suggest that innate response in shrimp is triggered instantaneously upon exposure to a bacterial component. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Angiotensin II receptor antagonist, L-158,809, prevents intimal hyperplasia in dog grafted veins

We investigated the levels of the angiotensin II-forming enzymes, chymase and angiotensin converting enzyme (ACE), in dog grafted veins, and studied the effect of an angiotensin II type 1 receptor antagonist, L-158,809, on vascular proliferation in the grafted veins. The right external jugular vein was grafted to the ipsilaterial carotid artery. In the group treated with L-158,809, the drug (10 mg/kg per day, p.o.) were administered orally from 7 days before the operation to 28 days after it, while the others were administrated placebo. In the placebo-treated group, the chymase activity in the grafted veins was increased about 10-fold and the ACE activity was doubled. The areas of intima and media were significantly increased in the grafted veins in the placebo-treated group. L-158,809 significantly reduced the intimal area of the grafted veins. An angiotensin II receptor antagonist, L-158,809, prevented the vascular proliferation in the grafted veins, and the development of the proliferation may depend on activation of local angiotensin II formation.     

4-Hydroxy hexenal derived from dietary n-3 polyunsaturated fatty acids induces anti-oxidative enzyme heme oxygenase-1 in multiple organs

It has recently been reported that expression of heme oxygenase-1 (HO-1) plays a protective role against many diseases. Furthermore, n-3 polyunsaturated fatty acids (PUFAs) were shown to induce HO-1 expression in several cells in vitro, and in a few cases also in vivo. However, very few reports have demonstrated that n-3 PUFAs induce HO-1 in vivo.     

l-Carnitine is essential to β-oxidation of quarried fatty acid from mitochondrial membrane by PLA2

Mitochondrial β-oxidation is an important system involved in the energy production of various cells. In this system, the function of l-carnitine is essential for the uptake of fatty acids to mitochondria. However, it is unclear whether or not endogenous respiration, ADP-induced O₂ consumption without substrates, is caused by l-carnitine treatment. In this study, we investigated whether l-carnitine is essential to the β-oxidation of quarried fatty acids from the mitochondrial membrane by phospholipase A₂ (PLA₂) using isolated mitochondria from the liver of rats. Intact mitochondria were incubated in a medium containing Pi, CoA and l-carnitine. The effect of l-carnitine treatment on ADP-induced mitochondrial respiration was observed without exogenous respiratory substrate. Increase in mitochondrial respiration was induced by treatment with l-carnitine in a concentration-dependent manner. Treatment with rotenone, a complex I blocker, completely inhibited ADP-induced oxygen consumption even in the presence of l-carnitine. Moreover, the l-carnitine dependent ADP-induced mitochondrial oxygen consumption did not increase when PLA₂ inhibitors were treated before ADP treatment. The l-carnitine-dependent ADP-induced oxygen consumption did contribute to ATP productions but not heat generation via an uncoupling system. These results suggest that l-carnitine might be essential to the β-oxidation of quarried fatty acids from the mitochondrial membrane by PLA₂.     

Genotypic variations in carbon isotope discrimination, transpiration efficiency, and biomass production in rice as affected by soil water conditions and N

Genotypic and environmental (soil water regime and N level) variation in carbon isotope discrimination (CID) in relation to the gas exchange, transpiration efficiency (A/T), and biomass production were investigated in field experiments using eleven rice (Oryza sativa L.) genotypes. The results showed that genotype was more dominant for variation in CID than in total biomass. Genotypic ranking in CID was consistent across environments because of small genotype × environment interactions. Japonica genotypes tended to have lower CID than indica genotypes. Higher soil water and lower N rate significantly increased CID. Variation in CID was slightly smaller for water regime than for genotype. There was a negative correlation between CID andA/T among genotypes within water regimes. Genotypic variation in CID was associated mainly with variation in stomatal conductance under all soil water regimes and with photosynthetic capacity in late growth stages under aerobic soil conditions. The decrease in CID at higher N was probably due to lower stomatal conductance under aerobic soil conditions and to higher photosynthetic rates under submerged soil conditions. The correlation between biomass and CID was not clear in aerobic soil, whereas it was positive in submerged soil, which indicated that the significance of lower or higher CID for improving biomass productivity may differ under different soil water regimes. Overall, the results implied a possible use of CID as a selection criterion for genotypic improvement inA/T and productivity in rice.     

Pseudodeflectusin, a novel isochroman derivative from Aspergillus pseudodeflectus a parasite of the sea weed, Sargassum fusiform, as a selective human cancer cytotoxin

A new isochroman derivative named pseudodeflectusin was isolated from a culture broth of Aspergillus pseudodeflectus. The structure was determined by spectroscopic means as 9-hydroxy-7-methyl-2-(methylethylidine)-furano[3,2-H]isochroman-3-one. This compound exhibited cytotoxicity for several human cancer cell lines from the stomach (NUGC-3), cervix (HeLa-S3), and peripheral blood (HL-60), but did not affect those from the lung (A549) or colon (DLD-1). The LD50 value of this compound for HL-60 cells was 39 microM.     

Genetically engineered rice containing larger amounts of nicotianamine to enhance the antihypertensive effect

Nicotianamine (NA), a metal chelator ubiquitous in higher plants, serves as an antihypertensive substance in humans. To engineer a novel antihypertensive rice that contains larger amounts of NA, the barley NA synthase gene, HvNAS1 , was introduced into rice via Agrobacterium -mediated transformation. The introduced HvNAS1 was driven by pGluB-1 , which induces strong gene expression in the endosperm of rice seeds. The NA content in transgenic rice seeds was up to fourfold greater than that in non-transgenic rice seeds. The Cre/ loxP DNA excision (CLX) system was used to remove the selectable marker gene for antibiotic resistance. Furthermore, the transgenic rice was crossed with a cleistogamous mutant to prevent gene transfer via pollen dispersal. These two modifications may minimize public concern with regard to the use of this transgenic rice.     

Improvement of isoflavone aglycones production using β-glucosidase secretory produced in recombinant Aspergillus oryzae

β-Glucosidase (BGL1) from Aspergillus oryzae was efficiently produced in recombinant A. oryzae using sodM promoter-mediated expression system. The yield of BGL1 was 960 mg/l in liquid culture, which is 20-fold higher than the yield of BGL1 produced using the yeast Saccharomyces cerevisiae. Recombinant BGL1 converted isoflavone glycosides into isoflavone aglycones more efficiently than β-glucosidase from almond. In addition, BGL1 produced isoflavone aglycones even in the presence of the insoluble form of isoflavone glycosides.     

Comparison of the DNA content of megakaryocytes identified immunologically with that identified morphologically

 We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole (DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls, the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced 0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients, the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore, this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients. Accepted: 29 April 1997