Combined deficiency of iron and other divalent cations mitigates the symptoms of iron deficiency in tobacco plants

To determine the responses of plants to deficiencies of multiple metals, tobacco plants ( Nicotiana tabacum L.) were subjected to treatments that were deficient in combinations of Fe and two other micronutrients, Zn and Mn. The response was measured using macro indices, including plant appearance, FW, chlorophyll concentration, and mineral concentrations, and with a molecular index, the barley ( Hordeum vulgare L.) Ids2 promoter / GUS fusion gene system (Yoshihara et al. 2003, Plant Biotech 20: 33–41). Tobacco plants grown in medium with combined deficiencies grew better and had higher chlorophyll concentrations than did plants grown on medium deficient in Fe only, although the measured Fe concentrations in the plant tissues were essentially the same. The Ids2/GUS expression responded to Fe deficiency, but not to Mn or Zn deficiencies in tobacco plants when Fe was present. Tobacco plants grown in medium with combined deficiencies had clearly detectable GUS activity, but the response was significantly lower than that in tobacco plants deficient in Fe only. The Fe-deficiency symptoms were mitigated at both the visible and molecular levels. Although more precise experimental evidence is needed to explain the mitigation mechanism, the balance of minerals was shown to be an important parameter to consider when estimating iron deficiency based on tobacco plant responses.     

Rabconnectin-3, a novel protein that binds both GDP/GTP exchange protein and GTPase-activating protein for Rab3 small G protein family.

Rab3A, a member of the Rab3 small G protein family, regulates Ca(2+)-dependent exocytosis of neurotransmitter. The cyclical activation and inactivation of Rab3A are essential for the Rab3A action in exocytosis. GDP-Rab3A is activated to GTP-Rab3A by Rab3 GDP/GTP exchange protein (Rab3 GEP), and GTP-Rab3A is inactivated to GDP-Rab3A by Rab3 GTPase-activating protein (Rab3 GAP). It remains unknown how or in which step of the multiple exocytosis steps these regulators are activated and inactivated. We isolated here a novel protein that was co-immunoprecipitated with Rab3 GEP and GAP by their respective antibodies from the crude synaptic vesicle fraction of rat brain. The protein, named rabconnectin-3, bound both Rab3 GEP and GAP. The cDNA of rabconnectin-3 was cloned from a human cDNA library and its primary structure was determined. Human rabconnectin-3 consisted of 3,036 amino acids and showed a calculated M(r) of 339,753. It had 12 WD domains. Tissue and subcellular distribution analyses in rat indicated that rabconnectin-3 was abundantly expressed in the brain where it was enriched in the synaptic vesicle fraction. Immunofluorescence and immunoelectron microscopy revealed that rabconnectin-3 was concentrated on synaptic vesicles at synapses. These results indicate that rabconnectin-3 serves as a scaffold molecule for both Rab3 GEP and GAP on synaptic vesicles.     

Classical MHC class I genes composed of highly divergent sequence lineages share a single locus in rainbow trout (Oncorhynchus mykiss).

The classical MHC class I genes have been known to be highly polymorphic in various vertebrates. To date, putative allelic sequences of the classical MHC class I genes in teleost fish have been reported in several studies. However, the establishment of their allelic status has been hampered in most cases by the lack of appropriate genomic information. In the present study, using heterozygous and homozygous fish, we obtained classical-type MHC class I sequences of rainbow trout (Oncorhynchus mykiss) and investigated their allelic relationship by gene amplification and Southern and Northern hybridization analyses. The results indicated that all MHC class I sequences we obtained were derived from a single locus. Based on this, a unique polymorphic nature of the MHC class I locus of rainbow trout has been revealed. The mosaic combination of highly divergent ancient sequences in the peptide-binding domains is notable, and the variable nature around the boundary between the alpha3 and transmembrane domains is unprecedented.     

Synthesis and biological evaluation of new 4-arylpiperidines and 4-aryl-4-piperidinols: dual Na(+) and Ca(2+) channel blockers with reduced affinity for dopamine D(2) receptors.

A series of novel 4-arylpiperidines and 4-aryl-4-piperidinols (2a-f, 3a-f and 4a-f) was synthesized and evaluated for blocking effects on both neuronal Na(+) and T-type Ca(2+) channels and binding affinity for dopamine D(2) receptors. Most of the compounds blockaded both ion channels with potency greater than or equal to flunarizine 1a which was adopted as a reference standard. In addition, these compounds had significantly reduced affinity for dopamine D(2) receptors which is common in this class of structure. Compounds 2a-f, 3a-f and 4a-f exhibited potent anticonvulsant effects following systemic (ip) administration on audiogenic seizures in DBA/2 mice, indicating their excellent brain permeability. The neuroprotective activity of 2a, 3a and 4a was also assessed in a transient middle cerebral artery occlusion (MCAO) model. These compounds significantly reduced neuronal damage without affecting ischemic hyperthemia, while flunarizine 1a produced only minor reductions. In particular, 4a had 1.7-fold the potency in this MCAO model but only 1/20 the affinity for dopamine D(2) receptors of 1a. The superposition of 2a, 3a and 4a on the basis of analyses of systematic conformation and similar structure has revealed that the cinnamyl, phenacyl and phenoxypropanol groups are likely to be structurally and biologically equivalent. Moreover, the superposition of 2a and 2f shows that diphenyl ether and biphenyl groups occupy a similar space, suggesting that both groups act as a bioisostere for the blockade of ion channels; however, this is not the case for dopamine D(2) receptors since only biphenyl compounds such as 2f had high affinity similar to flunarizine 1a. Compound 4a (SUN N5030) has a good pharmacological profile and may be useful in the alleviation and treatment of ischemic diseases.     

Estimation of field soil nitrogen mineralization and nitrification rates using soil N transformation parameters obtained through laboratory incubation

We tested the potential of estimating in-field (in situ) nitrogen (N) transformation rates based on soil temperature data and N transformation parameters (Q₁₀ and N transformation rates at standard temperature) obtained through laboratory incubations at three constant temperatures for 4 weeks. This test was conducted based on a comparison between in situ measurements and estimates using soils from 16 sites across 9 regions within the Japanese archipelago. The actual in situ N mineralization and nitrification rates measured using the buried-bag method at 0–50-cm-soil depth were 111 ± 34 and 106 ± 45 kg N ha^?1 year^?1, respectively, and estimates of both the rate and the amount were largely accurate. For rate alone, estimates were accurate in the 0–10-cm soil layer for annual and seasonal averages (except for spring–summer) whereas for amount alone, estimates were accurate to depths of 50 and 30 cm for N mineralization and nitrification, respectively. Thus, estimates of the rates and amounts were approximately equal to the actual in situ rate/amount, given the wide range of prediction intervals of the field measurement data. The differences between the estimates of N transformation rates derived from hourly measured and monthly average soil temperatures were negligible. Therefore, in situ soil N transformations, which are laborious to measure in the field, have the potential to be estimated from a combination of monthly average soil temperatures and N transformation parameters, which are relatively straightforward to obtain through laboratory incubation.     

The content and distribution of steryl ferulates in wheat produced in Japan

Oryzanol contained in rice bran is a complex mixture of steryl ferulates (SFs) with many identified health benefits. Recently, SF has been shown to exist in other cereals such as wheat, rye, and corn. In this study, SFs in several wheats produced in Japan were analyzed. For instance, SF content of whole wheat grain, Yumekaori (Japan) was 15.2 ± 1.4 mg-oryzanol-equivalent/100 g grain, while that of the imported one, 1CW (Canada) was 11.4 ± 1.3 mg-oryzanol-equivalent/100 g grain. The main SF components in the examined wheats were campesteryl ferulate, campestanyl ferulate, and sitostanyl ferulate. SF distribution in whole wheat grain was investigated using 14 fractions produced by a conventional test milling machine. SF was intensively accumulated in the four bran fractions (24 ? 95 mg-oryzanol-equivalent/100 g bran fraction). These results suggest that the wheat bran would be an important source of SF.     

Functional polymorphisms in inbred rat strains and their allele frequencies in commercially available outbred stocks.

Polymorphisms that have been proven to influence gene functions are called functional polymorphisms. It is significant to know the distribution of functional polymorphisms in the rat, widely used in animal models for human diseases. In this study, we assessed 16 functional polymorphisms consisting of 3 coat color and 13 disease-associated genes in 136 rat strains, as a part of the genetic profiling program of the National Bio Resource Project for the Rat (NBRP-Rat). Polymorphisms of Cdkn1a, Fcgr3, Grp10, Lss, and Fdft1, which were proven to function in prostate tumorigenesis, glomerulonephritis, hyperphagia, and cholesterol biosynthesis, were shared among various inbred strains. These findings indicated that most rat strains harbored the disease-associated alleles and suggested that many unidentified functional polymorphisms might exist in inbred rat strains. The functional polymorphisms shared in inbred strains were also observed within outbred stocks available commercially. Therefore, this implies that experimental plans based on either rat inbred strains or outbred stocks need to be carefully designed with a full understanding of the genetic characteristics of the animals. To select the most suitable strains for experiments, the NBRP-Rat will periodically improve and update the genetic profiles of rat strains.