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71.
This study aimed to comprehend a feature of single nucleotide polymorphism (SNP) in mitochondrial DNA (mtDNA) mainly of general broiler chickens in Japan. We typed two SNP sites (199C/T and 792A/G) of the D‐loop region in mtDNA by allele‐specific PCR (AS‐PCR) in 359 broiler (182 chunky and 177 cobb) and 506 layer (233 White Leghorn, 140 Barred Plymouth Rock and 133 Rhode Island Red) chickens. The SNP of 199C or 792A by AS‐PCR was observed in the chunky and cobb chickens, and not in the layers. The haplotype 199T/792G was observed in a part of cobb and all layers. By the result of AS‐PCR haplotyping and the broiler brands, the D‐loop region was sequenced in 44 broiler chickens (20 chunky and 24 cobb) and compared with the layers’ sequence data. Among the broiler and layer chickens, 21 SNP sites (including one insertion) and 11 sequence haplotypes were observed. Haplotype variation or correspondence was observed in and between the broiler brands. This study provides important information to establish a chicken meat traceability system by SNP haplotyping of mtDNA in Japan.  相似文献   
72.
Noble gas isotopes were measured in three rocky grains from asteroid Itokawa to elucidate a history of irradiation from cosmic rays and solar wind on its surface. Large amounts of solar helium (He), neon (Ne), and argon (Ar) trapped in various depths in the grains were observed, which can be explained by multiple implantations of solar wind particles into the grains, combined with preferential He loss caused by frictional wear of space-weathered rims on the grains. Short residence time of less than 8 million years was implied for the grains by an estimate on cosmic-ray-produced (21)Ne. Our results suggest that Itokawa is continuously losing its surface materials into space at a rate of tens of centimeters per million years. The lifetime of Itokawa should be much shorter than the age of our solar system.  相似文献   
73.
Many corals establish symbiosis with Symbiodiniaceae cells from surrounding environments, but very few Symbiodiniaceae cells exist in the water column. Given that the N-acetyl-d-glucosamine-binding lectin ActL attracts Symbiodiniaceae cells, we hypothesized that corals must attract Symbiodiniaceae cells using ActL to acquire them. Anti-ActL antibody inhibited acquisition of Symbiodiniaceae cells, and rearing seawater for juvenile Acropora tenuis contained ActL, suggesting that juvenile A. tenuis discharge ActL to attract these cells. Among eight Symbiodiniaceae cultured strains, ActL attracted NBRC102920 (Symbiodinium tridacnidorum) most strongly followed by CS-161 (Symbiodinium tridacnidorum), CCMP2556 (Durusdinium trenchii), and CCMP1633 (Breviolum sp.); however, it did not attract GTP-A6-Sy (Symbiodinium natans), CCMP421 (Effrenium voratum), FKM0207 (Fugacium sp.), and CS-156 (Fugacium sp.). Juvenile polyps of A. tenuis acquired limited Symbiodiniaceae cell strains, and the number of acquired Symbiodiniaceae cells in a polyp also differed from each other. The number of Symbiodiniaceae cells acquired by juvenile polyps of A. tenuis was correlated with the ActL chemotactic activity. Thus, ActL could be used to attract select Symbiodiniaceae cells and help Symbiodiniaceae cell acquisition in juvenile polyps of A. tenuis, facilitating establishment of symbiosis between A. tenuis and Symbiodiniaceae cells.  相似文献   
74.
Phytase (myo-inositol hexakisphosphate phosphohydrolase; EC 3.1.3.8) was purified from roots of tomato plants grown under phosphorus-deficient conditions using five purification schemes. The phytase was successfully separated from the major acid phosphatase to an electrophoretic homogeneity. The native molecular weight of this enzyme was estimated to be about 164 kD by Bio-Gel P-200 gel filtration. The molecular weight of the subunit on SDS-PAGE was approximately 82 kD, indicating that the native form of the enzyme was a homodimer. The isoelectric point of tomato phytase was about 5.5. The enzyme exhibited a high affinity for phytic acid (K m = 38 μM), and was strongly inhibited by phosphate, molybdate and fluoride. Among other characteristics of tomato phytase, the pH and temperature optima were 4.3 and 45°C, respectively. Tomato phytase contained a fairly high concentration of aspartic, glutamic acid and glycine residues.  相似文献   
75.
The PIT1 gene which is highly homologous with phosphate transporter was isolated from Catharanthus roseus and analyzed. The cBNA PIT1 contained an open reading frame of 542 amino acids and its sequence showed a 31, 30, and 34% identity with the phosphate transporter of Saccharomyces cerevisiae (PBO84), Neurospora crassa (PHO-5), and Glomus versiforme (GvPT), respectively. Furthermore, the cDNA PIT1 encoded a highly hydrophobic protein with 12 putative membrane-spanning regions and contained a conserved amino acid sequence reported in the human glucose transporter super-family* S. cerevisiae strain DpU (pho84 knockout strain) was unable to grow on low phosphate (55 μM) medium (LP medium). Expression of the PIT1 cDNA enabled DpU to grow on LP medium. Northern hybridization analysis revealed that the PIT1 gene was expressed in roots, stems, and young whole plant of C. roseus, but not in leaves.  相似文献   
76.
Mineral composition including AI, Ca, Mg, P, S, and Si and relationships between Al and other elements such as Ca, Mg, P, S, and Si in leaves and bark of trees in a tropical rain forest in West Sumatra were studied. Sixty five tree species and 12 unidentified trees were referred to as AI accumulators based on Chenery\s's definition (more than 1 g kg-1 Al in leaves). For most of the Al accumulators, Al concentration in leaves was higher than in bark. However, some members of Euphorbiaceae, Melastomataceae, and Ulmaceae families showed a reverse trend. Most of the non-accumulators also showed a higher Al concentration in bark than in leaves. These results indicated that there was a difference in the mechanism of Al accumulation in tree bodies. Some of the Al accumulators showed an extremely high Al concentration (more than 10 g kg-1) not only in the mature leaves, but also in the new leaves. Analysis of the relationships between the concentration of Al and the other 5 elements in leaves, revealed that Al accumulators could be separated into two groups at the Al concentration of 3 g kg-1. This finding suggested that new criteria based on Al concentration (23 g kg-1) or Al/Ca ratio in leaves could be proposed in order to define Al accumulators, apart from Chenery's criterion. Aluminium accumulators with an Al concentration in leaves lower than 3 g kg-1 (AI accumulators <3 g kg-1) showed the same trend as the non-accumulators in terms of these elemental relationships, while Al accumulators with an Al concentration in leaves higher than 3 g kg-1 (AI accumulators 23 g kg-1) showed a different trend from the non-accumulators. The Al accumulators 23 g kg-1 and the other trees (AI accumulators < 3 g kg-1 and non-accumulators) showed separately positive correlations between the concentrations of AI and Ca (or Mg) in the leaves. This observation seems to be opposite to general findings in plant nutrition, i.e. inhibition of Ca or Mg uptake by AI. A positive correlation between Al and S was also observed for all the trees. The Al accumulators ≥3 g kg-1 showed positive correlations between the concentrations of Al and P (or Si) in the leaves, unlike the other trees. These findings suggested that Al stimulated P, S, or Si accumulation in leaves or Al was transported with P, S, or Si for the Al accumulators ≥3 g kg-1. No negative relationships between Al and the other 5 elements in the leaves were observed for the Al accumulators ≥3 g kg-1.  相似文献   
77.
We studied microbe-plant interactions of white lupin, a cluster root-forming plant, under low P and N conditions to examine increased nutrient acquisition by plants either by a shift to a more specialized microbial community or changes in microbial enzyme production. White lupin plants were grown in rhizoboxes filled with either P- or N-deficient soil; fertilized soil was used as control. After cultivation of plants in a glasshouse for 41 d, plant growth (shoot and roots) and P and N accumulation in shoots were measured. Microbial functions were analyzed by P- and N-cycling enzymes. The microbial community structure was estimated by fingerprinting (denaturing gradient gel electrophoresis) and sequencing techniques. P deficiency induced the released citrate and acid phosphomonoesterases from cluster roots and stimulated the production of microbe-derived alkaline phosphomonoesterase in the rhizosphere. P deficiency decreased microbial diversity in the cluster root rhizosphere. Increased relative abundance of Burkholderiales in the rhizosphere of P deficient plants might be responsible for the degradation of different organic P fractions such as phytates. N deficiency induced an increase of the number of nodules and P concentration in shoot as well as roots of white lupin. We clarified that high release of citrate from cluster roots might be the preferred mechanisms to meet the P demand of nodulated plants under N deficiency. In addition, the high abundance of Rhizobiales and Rhodospirillales in the rhizosphere of cluster roots showed that the importance of N-fixing microorganisms under N deficiency. The contribution of rhizosphere microorganisms due to similar activities of N-cycling enzymes under the two different N treatments is less important for N nutrition of plants. Further understanding of the regulation of cluster roots under N-deficiency will provide new information on the interactions between P and N nutrition.  相似文献   
78.
Moisture distribution in individual polished rice grains was observed during soaking by magnetic resonance (MR) imaging, and a nuclear magnetic resonance (NMR) signal intensity profile (SI-profile) was generated from the MR image. The water penetration pattern during soaking roughly showed dissimilar trends between different varieties of japonica and japonica-indica hybrid rice. NMR signal intensity at the completion of water absorption varied within each grain; high at the periphery and the central region and low in the area between the periphery and the central region. High moisture content within the central region is due to loosely packed starch granules. The SI-profile was congruent for grains of the same variety harvested in different regions and years and characterized a grain moisture distribution for each variety. Moisture distribution was compared using SI-profiles for varieties with different amylose contents and new varieties bred for specific end-uses in Japan. The NMR signal intensity, which is related to the moisture content, at the surface of soaked grain was negatively correlated to the grain amylose content. The NMR signal intensities at the surface of soaked grain negatively correlated with the overall hardness of the cooked rice grain as measured by the single-grain low-high compression test.  相似文献   
79.
80.
The aim of this study was to demonstrate the enhancement of the vasorelaxation power of the antiatherosclerotic voltage-dependent L-type Ca(2+) channel (VDCC)-blocking peptide Trp-His by epigallocatechin gallate (EGCg). We found that 300 μM EGCg dramatically enhanced the magnitude of Trp-His-induced vasorelaxation by a factor of >6 (EC(50) of Trp-His: EGCg(-), 2.80 ± 0.05 mM; EGCg(+), 0.45 ± 0.04 mM) in phenylephrine-contracted rat aorta. The enhancing effect of EGCg was completely abolished in endothelium-removed aorta and high K(+)-contracted aorta. The enhancement of Trp-His-induced vasorelaxation by EGCg was significantly diminished by either N(G)-monomethyl-l-arginine acetate (NO synthase (NOS) inhibitor) or 1-H-[1,2,4]oxadiazolo[4,3]quinoxalin-1-one (soluble guanylyl cyclase inhibitor), together with the enhancement of NOS activity by EGCg. These results indicate that the enhancing effect of EGCg in Trp-His-induced vasorelaxation may be involved in the activation of NO/cGMP pathway.  相似文献   
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