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An attenuated mutant strain of melon yellow spot virus (MYSV), an Orthotospovirus, designated as SA08-8, was obtained from a pathogenic isolate, C95S, via high temperature treatment, single local lesion isolation, and serial mechanical inoculation. Under greenhouse conditions, the SA08-8 strain conferred the cross-protection against wild-type MYSV but it was not transmissible by its known natural vector melon thrips. In SA08-8 genome, a total of 16 amino acid substitutions were found in the genes encoding RNA-dependent RNA polymerase, glycoprotein precursor, and nonstructural S protein. This attenuated mutant strain is a potential biocontrol agent for MYSV-induced crop diseases in the field.

Plant high-affinity K+ (HAK) transporters are divided into four major clusters. Cluster I transporters, in particular, are thought to have high-affinity for K+. Of the 27 HAK genes in rice, eight HAK transporters belong to cluster I. In this study, we investigated the temporal expression patterns during K+ deficiency and K+ transport activity of these eight HAK transporters. The expression of seven HAK genes except OsHAK20 was detected. Expression of OsHAK1, OsHAK5 and OsHAK21 was induced in response to K+ deficiency; however, that of other genes was not. Six of the eight HAK transporters-OsHAK1, OsHAK5, OsHAK19, OsHAK20, OsHAK21, and OsHAK27-complemented the K+-transporter-deficient yeast or bacterial strain. Further, the yeast cells expressing OsHAK1 were more sensitive to Na+ than those expressing OsHAK5. Mutant analysis showed that the high-affinity K+ uptake activity was almost undetectable in oshak1 mutants in a low-K+ medium (0.02 mM). In addition, the high-affinity K+ uptake activity of wild-type plants was inhibited by mild salt stress (20 mM NaCl); however, Na+ permeability of OsHAK1 was not detected in Escherichia coli cells. The high-affinity K+ uptake activity by leaf blades was detected in wild-type plants, while it was not detected in oshak1 mutants. Our results suggest that OsHAK1 and OsHAK5 are the two important components of cluster I corresponding to low-K+ conditions, and that the transport activity of OsHAK1, unlike that of OsHAK5, is sensitive to Na+. Further, OsHAK1 is suggested to involve in foliar K+ uptake.

Rice MTP11 is the trans-Golgi-localized transporter that is involved in Mn tolerance with MTP8.1, and it is required for normal fertility. Rice (Oryza sativa L.) is one of the most manganese (Mn)-tolerant species, and it is able to accumulate high levels of this metal in the leaves without showing toxic symptoms. The metal tolerance protein 8.1 (MTP8.1), a member of the Mn-cation diffusion facilitator (CDF) family, has been shown to play a central role in high Mn tolerance by sequestering Mn into vacuoles. Recently, rice MTP11 was identified as an Mn transporter that is localized to Golgi-associated compartments, but its exact role in Mn tolerance in planta has not yet been understood. Here, we investigated the role of MTP11 in rice Mn tolerance using knockout lines. Old leaves presented higher levels of constitutively expressed MTP11 than other tissues and MTP11 expression was also found in reproductive organs. Fused MTP11:green fluorescent protein was co-localized to trans-Golgi markers and differentiated from other Golgi-associated markers. Knockout of MTP11 in wild-type rice did not affect tolerance and accumulation of Mn and other heavy metals, but knockout in the mtp8.1 mutant showed exacerbated Mn sensitivity at the vegetative growth stage. Knockout of MTP11 alone resulted in decreased grain yield and fertility at the reproductive stage. Thus, MTP11 is a trans-Golgi localized transporter for Mn, which plays a role in Mn tolerance through intracellular Mn compartmentalization. It is also required for maintaining high fertility in rice.

A new iron-based superconductor (Ca,Pr)FeAs2 was discovered. Plate-like crystals of the new phase were obtained and crystal structure was investigated by single-crystal X-ray diffraction analysis. The structure was identified as the monoclinic system with space group P21/m, and is composed of two Ca(Pr) planes, anti-fluorite Fe2As2 layers, and As2 zigzag chain layers. Plate-like crystals composed of the new phase showed superconductivity with Tc ~20 K in both magnetization and resistivity measurements.

To clarify roles of an endogenous pain modulatory system of the central nervous system (CNS) in hyperalgesia, we tried to identify qualitative and quantitative protein changes by a proteomic analysis using an animal model of hyperalgesia. Specifically, we first induced functional hyperalgesia on male Wistar rats by repeated cold stress (specific alternation of rhythm in temperature, SART). We then compared proteomes of multiple regions of CNS and the dorsal root ganglion between the hyperalgetic rats and non-treated ones by 2-D PAGE in the pI range of 4.0-7.0. We found that SART changed the proteomes prominently in the mesencephalon and cerebellum. We thus analyzed the two brain regions in more detail using gels with narrower pI ranges. As a result, 29 and 23 protein spots were significantly changed in the mesencephalon and the cerebellum, respectively. We successfully identified 12 protein spots by a MALDI-TOF/TOF MS and subsequent protein database searching. They included unc-18 protein homolog 67K, collapsin response mediator protein (CRMP)-2 and CRMP-4, which were reported to be involved in neurotransmitter release or axon elongation. Interestingly, mRNA expression levels of these three proteins were not changed significantly by the induction of hyperalgesia. Instead, we found that the detected changes in the protein spots are caused by the post-translational modification (PTM) of proteolysis or phosphorylation. Taken together, development of the hyperalgesia would be linked to PTM of these three CNS proteins. PTM regulation may be one of the useful ways to treat hyperalgesia.

Regulation of K+/Na+ homeostasis is an important mechanism in plant growth. The high-affinity K+ uptake system plays a central role in this mechanism especially when plants experience environmental stresses of K+ starvation and high salinity. K+ channels and the K+/Na+ co-transporter like HKT have been closely studied as principal members of the K+ transport system in plants. The KT/HAK/KUP family is a major K+ transporter family present in bacteria, fungi and plants. In plants, the KT/HAK/KUP transporters form a large family. Arabidopsis thaliana has 13 genes and rice has at least 25. KT/HAK/KUP transporters serve various functions in various K+ traffic, but their physiological roles are still unclear. Plant KT/HAK/KUP transporters could be divided into 4 related clusters according to their amino acid sequences, the character of transporters belongs to each cluster was summarized. We analyzed the expression of OsHAK genes in rice roots under both K+ starvation and salt stress conditions.

Beta vulgaris L. accumulates a large amount of glycinebetaine (betaine), a metabolite that is related to salt- tolerance. Production of betaine involves expression of many genes that encode enzymes such as betaine aldehyde dehydrogenase, choline monooxygenase, phosphoethanolamine N-methyltransferase, S-adenosyl-L-methionine synthetase, S-adenosyl-L-homocysteine hydrolase, and methionine synthase. We examined transcriptional regulation of the betaine- related genes in leaf beet (Beta vulgaris L. var cicla, cv. shirogukifudanna). Transcript expression of these betaine-related genes in leaf tissue had the following common features: (1) a similar pattern of transcript induction under salt stress, (2) reduced induction under salt stress in a dark condition, and (3) diurnal rhythms of transcript levels under a photoperiod of 16 h light/8 h darkness. The co-regulation of transcripts may contribute to the effective betaine production without disturbing the biosynthesis of other products in leaf beet.

Incorporation of different structured synthetic hemes, 5,10,15,20-tetraphenylporphyrinatoiron(II) derivetives with a covalently linked proximal base [FeP(1) to FeP(7)], into human serum albumin (HSA), provides seven types of albumin-heme hybrids (HSA-FeP) with different O 2 -binding abilities. An HSA host absorbs a maximum of eight FeP molecules in each case. The obtained all HSA-FePs can reversibly bind and release O 2 under physiological conditions (in aqueous media, pH 7.3, 37 °C) as similar as hemoglobin and myoglobin. The difference in the fence structures did not affect the O 2 -binding parameters, however the axial histidine coordination significantly increased the O 2 -binding affinity, which is ascribed to the low O 2 -dissociation rate constants. The most remarkable effect of the heme structure appeared in the half-lifetime (τ 1/2 ) of the O 2 -adduct complex. The dioxygenated rHSA-FeP(4) showed an unusually long lifetime (τ 1/2 : 25 hr at 37 °C) which is ca. 13-fold longer than that of rHSA-FeP(1).

New Zealand Black (NZB) mice are a well-known animal model of human autoimmune disease. Although the mechanism for development of autoimmunity is unclear, NZB mice are well known for severe thymic microarchitecture abnormalities. It is thought that thymic dendritic cells (DC) may play a role in thymic education and contribute to the autoimmune process. To address this issue and, in particular, that qualitative and/or quantitative differences exist in thymic DC, we took advantage of a novel restriction analysis system that allow definition of differences in the expression of tyrosine kinases using highly enriched populations of thymic DC from NZB compared to BALB/c and C57BL/6 mice. The method chosen, restriction analysis of gene expression, allowed the determination of protein tyrosine kinase transcription profiles. We report herein that NZB mice have a significant upregulation of C-met compared to the control strains. The abnormality of the C-met transcription was confined to thymic DC. We believe that its abnormal expression reflects the resistance of thymic cells to apoptosis, which will ultimately lead to defects and/or abnormal signaling by the interaction of thymic DC and thymocytes. Further studies involving such interactions are under way.

Double-sided porphinatoiron(II)s with polar substituents [R; hydroxy (FeDP(OH)), methoxy (FeDP(OMe)), and acetoxy (FeDP(OAc))] on the 2,2-dimethylpropanoyloxy-fence groups have been synthesized. FeDP(OMe) and FeDP(OAc) formed five-N-coordinated high-spin Fe2+ complexes with an intramolecularly bound axial imidazole in toluene (or CH2Cl2) under an N2 atmosphere. Upon the addition of O2, they produced stable O2 adducts at 25 °C; their half-lives in water-saturated toluene (50–77 h) are 2–3 fold longer compared to that of the single-face encumbered porphinatoiron(II) (FeP). Their O2-binding parameters are almost identical to that of FeDP(H), which has nonpolar substituents on the fences. In contrast, FeDP(OH) showed a significantly low O2-binding affinity and was immediately oxidized to the Fe3+ state after contact with bubbling O2 gas. The incorporation of these FeDPs into the human serum albumin (HSA) provided artificial hemoproteins, which can reversibly bind and release O2 under physiological conditions ...

The nucleus of the optic tract (NOT) in the pretectum in both afoveate and foveate mammals has been considered to be the interface between the retina and premotor nuclei in the pathway conveying signals responsible for horizontal optokinetic nystagmus (OKN). Howevr, the parts of the retina and the kinds of retinal ganglion cells project which their fibers into the NOT are still not completely known.To clarify this pathway, we injected horseradish peroxidase conjugated with wheatgerm agglutinin into the NOT of the cats. In both retinae, labeled retinal ganglion cells were observed only above the horizontal meridian through the optic disc, and they were situated mainly in the temporal retina lateral to a vertical line through the disc.In both retinae, the highest concentration of labeled cells was the area centralis and the region adjacent to it. Most of the labeled cells were small cells, i.e., W cells.However, X-like cells and Y-like cells were also definitely labeled, suggesting that these cells pariticipate in OKN.

Potassium ion (K(+)) plays vital roles in many aspects of cellular homeostasis including competing with sodium ion (Na(+)) during potassium starvation and salt stress. Therefore, one way to engineer plant cells with improved salt tolerance is to enhance K(+) uptake activity of the cells, while keeping Na(+) out during salt stress. Here, in search for Na(+)-insensitive K(+) transporter for this purpose, bacterial expression system was used to characterize two K(+) transporters, OsHAK2 and OsHAK5, isolated from rice (Oryza sativa cv. Nipponbare). The two OsHAK transporters are members of a KT/HAK/KUP transporter family, which is one of the major K(+) transporter families in bacteria, fungi and plants. When expressed in an Escherichia coli K(+) transport mutant strain LB2003, both OsHAK transporters rescued the growth defect in K(+)-limiting conditions by significantly increasing the K(+) content of the cells. Under the condition with a large amount of extracellular Na(+), we found that OsHAK5 functions as a Na(+)-insensitive K(+) transporter, while OsHAK2 is sensitive to extracellular Na(+) and exhibits higher Na(+) over K(+) transport activities. Moreover, constitutive expression of OsHAK5 in cultured-tobacco BY2 (Nicotiana tabacum cv. Bright Yellow 2) cells enhanced the accumulation of K(+) but not Na(+) in the cells during salt stress and conferred increased salt tolerance to the cells. Transient expression experiment indicated that OsHAK5 is localized to the plant plasma membrane. These results suggest that the plasma-membrane localized Na(+) insensitive K(+) transporters, similar to OsHAK5 identified here, could be used as a tool to enhance salt tolerance in plant cells.

In this paper a transport model for pervaporation based on the pore-flow mechanism was tested by examining whether it could describe main features observed in pervaporation experiments. The pervaporation systems used for the above test include mixtures of ethanol/n-heptane, methanol/ethanol, 2-propanol/water and cyclohexane/benzene. Membrane polymeric materials such as cellulose, cellulose diacetate-triacetate blend, polyamide, polyethylene and poly(γ-methyl- l -glutamate) are also included in this study. Membranes are either asymmetric or homogeneous but not of composite nature. Separation of organic mixtures by vapor permeation was also discussed in relation to pervaporation.

A study was carried out on the separation of ethyl alcohol/heptane mixtures by pervaporation using cellulose membranes of different pore sizes. Permeation data of pure ethyl alcohol and pure heptane were also obtained. The experimental data were further analyzed by using a transport theory developed on the basis of the pore flow mechanism. The latter mechanism consists of the following three consecutive steps: (1) liquid transport from the pore inlet to the liquid-vapor phase boundary; (2) evaporation at the phase boundary; (3) vapor transport from the phase boundary to the pore outlet. Using the above mechanism a set of transport equations was derived. It was shown that the trend in the pervaporation experimental data could be represented very well by proposed equations. A comparison was made between equations derived on the basis of the pore flow mechanism and those derived on the basis of the solution-diffusion mechanism.

The membrane performance data were computed for different values of parameters involved in the transport equations for pervaporation developed on the basis of the pore flow model. For the calculation the separation of ethanol/water mixtures by pervaporation was chosen as an example. The applicability of the transport equations was tested by examining the agreement between tendencies observed in the calculated data and those in a variety of experimental data recorded in the literature. The effects of the downstream pressure and the temperature on the pervaporation performance were also discussed from theoretical and experimental view points.

Porous cellulose and polyvinyl alcohol membranes were tested for dehydration of oil-water emulsion by pervaporation at different temperatures. Membranes having pore sizes that correspond to those of ultrafiltration membranes removed water effectively from oil-water emulsions. The permeation rate decreased with an increase in the oil content in the emulsion, probably due to a gradual change in the emulsion structure from the w/o/w (water-oil-water) to the o/w/o (oil-water-oil) type. The permeation rate increased with an increase in the operating temperature without a significant change in the oil separation.

Adenine, guanine, thymine and cytosine monomers of oxy-peptide nucleic acid that contain a pyrrolidine ring in the main chain have been synthesized for use in the synthesis of novel peptide nucleic acid.

Fibroblast growth factor 23 (FGF23) is a member of the fibroblast growth factor superfamily which displays a strong phosphaturic action and an inhibition of vitamin D 1-alpha hydroxylase activity. Fourty-six patients undergoing maintenance hemodialysis therapy participated in the study. They were randomly divided into 2 groups, and treated with either 3 g sevelamer hydrochloride+3 g of calcium bicarbonate (CaCO3), or 3 g of CaCO3 alone. Serum FGF23 levels were determined by a sandwich enzyme-linked immunosorbent assay (ELISA) system that detects the intact form of FGF23 molecules. Although the serum inorganic phosphate (Pi) levels were comparable before treatment, the levels were significantly lower in the patients treated with sevelamer hydrochloride+CaCO3 than those with CaCO3 alone after 4 weeks of treatment (P

We have developed a new series of oxy-peptide nucleic acids with pyrrolidine rings of four different types of structural isomers (cis L, cis D, trans L, trans D configurations; POPNAs). Melting curves of adenine nanomers of POPNAs in the presence of the complementary DNA showed the highest Tm value for cis L-POPNA, but in the case of RNA, the highest Tm value was observed for trans L-POPNA. Thermodynamic parameters (delta H and delta S) of POPNA/DNA and POPNA/RNA hybridizations were evaluated from concentration dependence of Tm values. The POPNA/DNA and POPNA/RNA hybridizations were governed by entropy and enthalpy terms, respectively.

Four stereoisomers of oxy-peptide nucleic acids containing ether linkages in the main chain and conformationally-restricted pyrrolidine rings (pyrrolidine-based oxy-PNA = POPNA) were newly synthesized and investigated for binding to DNA. cis-L-POPNA with 9 adenine bases formed the most stable hybrid with dT9. The POPNA showed high sequence specificity similar to that of the Nielsen-type PNA and sharper melting behavior in hybridization with DNA than the Nielsen-type PNA.