A novel third chromosomal locus controls susceptibility to Autographa californica multiple nucleopolyhedrovirus in the silkworm,Bombyx mori

Baculovirus demonstrates specific infection spectrums and thus one certain host exhibits particular response to single baculovirus isolate. Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is considered to be not an innate pathogen to Bombyx mori, but some silkworm strains have been identified to be permissive to AcMNPV, indicating the positive or negative involvement of certain host factors in baculovirus replications in vivo. To provide a fundamental knowledge of this process, we performed large-scale screening to investigate the responses of 448 silkworm strains against recombinant AcMNPV inoculation. By genetic analysis between permissive and resistant strains identified, we further confirmed that a potential corresponding locus on chromosome 3 regulates host responses to AcMNPV in silkworm. Additionally, we found that it is available for AcMNPV–silkworm baculovirus expression vector system to produce proteins of interest.     

Adsorbents for Apheresis Prepared from Polysaccharides of Algae that Threaten Ecosystem Services

In this work, we investigated whether materials isolated from algae that threaten ecosystems can be used for human benefit. We converted acidic polysaccharides (ulvan) from the alga Ulva pertusa into soft hydrogel materials. In addition to ulvan, the hydrogels also contained alginate in a polyion complex with chitosan. Cross‐linking the hydrogel with glutaraldehyde reduced polysaccharide elution from the polyion complex gel. We also found that both ulvan? chitosan and alginate? chitosan gels were able to remove urea and heavy metals from aqueous solution. This is clinically significant, since during apheresis, toxic compounds such as urea have to be removed from the bloodstream of patients. Importantly, albumin was not removed by the hydrogels, implying that this vital protein can be returned to the bloodstream following dialysis.     

Modification of synapse formation of accessory olfactory bulb neurons by coculture with vomeronasal neurons

Previously, a coculture system of accessory olfactory bulb (AOB) neurons and vomeronasal (VN) neurons was established for studying the functional roles of AOB neurons in pheromonal signal processing. In this study, the effect of VN neurons on the development of AOB neurons was examined in a coculture system. Spine density was quantitatively measured for various culture periods of 21, 28, 36, and 42 days in vitro. The densities of dendritic spines were lower in the coculture than in single culture for all periods in vitro. Synapse formation on spines was analyzed immunocytochemically using an anti-synaptophysin antibody. The ratio of the density of synaptophysin-immunopositive spine/total spine density was larger in the coculture than in the single culture. The volume of spine head was larger in the coculture than in single culture. These changes were not observed in the coculture in which there was no physical contact between AOB neurons and VN neurons. These observations suggest that synapse formation on the spines of AOB neurons is modified by physical contact with VN neurons.     

Hydroxylated poly(N-isopropylacrylamide) as functional thermoresponsive materials

In this study, we developed a poly(N-isopropylacrylamide)-based thermoresponsive polymeric material with a high content of hydroxyl groups. We newly designed the functional monomer, N-(2-hydroxyisopropyl)acrylamide (HIPAAm), considering maintaining the continuous and repeated structure of the isopropylamide group after copolymerization and the monomer reactivity ratios. The thermoresponsive polymer was derived by conventional radical copolymerization of HIPAAm with N-isopropylacrylamide (NIPAAm) in high yield. Estimation of monomer reactivity ratios, r(1) and r(2), supported the almost random sequence of the comonomers. The obtained copolymers showed a very sensitive phase transition and/or separation in response to temperature in aqueous media although they have many hydrophilic parts, and their thermoresponsive behavior was not affected by the pH. Furthermore, the cloud points of these copolymers closely depended on the HIPAAm content and could be easily controlled by adding salts. HIPAAm is expected to regulate the phase transition and/or separation temperature of the NIPAAm-based copolymers while maintaining their desirable sensitive thermoresponse. Differential scanning calorimetric analysis showed that dehydration of the polymer chains occurring in phase transition became incomplete with increasing HIPAAm content. Moreover, it was found that poly(NIPAAm-co-HIPAAm) having a high content of the HIPAAm unit showed liquid-liquid phase separation involving coacervation. The sizes of the coacervate droplets were relatively monodisperse and very minimal. Poly(NIPAAm-co-HIPAAm) is valuable for use in biomedical fields such as bioseparation.     

Grifolin derivatives from Albatrellus caeruleoporus, new inhibitors of nitric oxide production in RAW 264.7 cells

Two new farnesyl phenols named grifolinones A and B, together with known grifolin and neogrifolin, were isolated from methanolic extract of the inedible mushroom Albatrellus caeruleoporus. Their structures were characterized by a combination of 2D NMR, MS, IR, and UV spectra. Grifolinone B was composed of two grifolin molecules, which were connected by a C-C bond. Grifolinones A and B, grifolin, and neogrifolin exhibited inhibitory activity against nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells with IC50values of 23.4, 22.9, 29.0, and 23.3 microM, respectively.     

Conformational changes of the phenyl and naphthyl isocyanate-DNA adducts during DNA replication and by minor groove binding molecules

DNA lesions produced by aromatic isocyanates have an extra bulky group on the nucleotide bases, with the capability of forming stacking interaction within a DNA helix. In this work, we investigated the conformation of the 2′-deoxyadenosine and 2′-deoxycytidine derivatives tethering a phenyl or naphthyl group, introduced in a DNA duplex. The chemical modification experiments using KMnO₄ and 1-cyclohexyl-3 -(2-morpholinoethyl) carbodiimide metho-p-toluenesulfonate have shown that the 2′-deoxycytidine lesions form the base pair with guanine while the 2′-deoxyadenosine lesions have less ability of forming the base pair with thymine in solution. Nevertheless, the kinetic analysis shows that these DNA lesions are compatible with DNA ligase and DNA polymerase reactions, as much as natural DNA bases. We suggest that the adduct lesions have a capability of adopting dual conformations, depending on the difference in their interaction energies between stacking of the attached aromatic group and base pairing through hydrogen bonds. It is also presented that the attached aromatic groups change their orientation by interacting with the minor groove binding netropsin, distamycin and synthetic polyamide. The nucleotide derivatives would be useful for enhancing the phenotypic diversity of DNA molecules and for exploring new non-natural nucleotides.     

Characterization and expression analyses of two plastidic enolase genes in rice

To verify the presence of enolase related to the chloroplastic glycolysis in rice, database search was carried out and identified seven putative enolase genes in the rice genome. Among them, OsEno1 and OsEno3 encode long proteins with N-terminal extensions. GFP protein fusions of these N-terminal extensions were both targeted to plastids of onion epidermal cell. Promoter::GUS analysis showed that OsEno3 was highly expressed in young developing leaves, but its expression was drastically decreased during leaf development and greening. On the other hand, the expression of OsEno1 was low and detected in limited portions such as leaf sheath at the tiller base. Recombinant OsEno1 protein showed enolase activity with a pH optimum at pH 8.0, whereas OsEno3 did not exhibit detectable activity. Although it remains obscure if OsEno3 encodes a functional enolase in vivo, our results demonstrate that the entire glycolytic pathway does not operate in rice chloroplasts.