Seismic Behavior of Batter Pile Foundation: Kinematic Response

We carried out centrifuge tests to clarify the seismic behavior of batter-pile foundations. A vertical-pile foundation and a batter-pile foundation without the presence of a superstructure were installed parallel to each other in a soil container filled with dry sand, and were excited simultaneously. Through a comparison of the acceleration and displacement response of the footing, as well as the axial and bending strain of the piles for the two pile foundations, the kinematic response of the seismic behavior of the batter-pile foundation was experimentally investigated

Intake of Radionuclides in the Trees of Fukushima Forests 5. Earthquake Could Have Caused an Increase in Xyloglucan in Trees

A megathrust earthquake caused the Fukushima–Daiichi nuclear power plant accident, which dispersed abundant radioiodines, causing them to be bound to xyloglucan into forest trees. Nevertheless, targeted xyloglucan was found in increased quantities in the annual rings of forest trees affected by the earthquake. We propose that trees could acclimate rapidly to shaking stress through an increase in xyloglucan deposition as a plant response under natural phenomena

Comparative genomic analysis of 1047 completely sequenced cDNAs from an Arabidopsis-related model halophyte, Thellungiella halophila

<p>Abstract</p> <p>Background</p> <p><it>Thellungiella halophila </it>(also known as <it>T. salsuginea</it>) is a model halophyte with a small size, short life cycle, and small genome. <it>Thellungiella </it>genes exhibit a high degree of sequence identity with Arabidopsis genes (90% at the cDNA level). We previously generated a full-length enriched cDNA library of <it>T. halophila </it>from various tissues and from whole plants treated with salinity, chilling, freezing stress, or ABA. We determined the DNA sequences of 20 000 cDNAs at both the 5'- and 3' ends, and identified 9569 distinct genes.</p> <p>Results</p> <p>Here, we completely sequenced 1047 <it>Thellungiella </it>full-length cDNAs representing abiotic-stress-related genes, transcription factor genes, and protein phosphatase 2C genes. The predicted coding sequences, 5'-UTRs, and 3'-UTRs were compared with those of orthologous genes from Arabidopsis for length, sequence similarity, and structure. The 5'-UTR sequences of <it>Thellungiella </it>and Arabidopsis orthologs shared a significant level of similarity, although the motifs were rearranged. While examining the stress-related <it>Thellungiella </it>coding sequences, we found a short splicing variant of <it>T. halophila </it><it>salt overly sensitive 1 </it>(<it>ThSOS1</it>), designated <it>ThSOS1S</it>. ThSOS1S contains the transmembrane domain of ThSOS1 but lacks the C-terminal hydrophilic region. The expression level of <it>ThSOS1S </it>under normal growth conditions was higher than that of <it>ThSOS1</it>. We also compared the expression levels of Na⁺-transport-system genes between <it>Thellungiella </it>and Arabidopsis by using full-length cDNAs from each species as probes. Several genes that play essential roles in Na⁺excretion, compartmentation, and diffusion (<it>SOS1</it>, <it>SOS2</it>, <it>NHX1</it>, and <it>HKT1</it>) were expressed at higher levels in <it>Thellungiella </it>than in Arabidopsis.</p> <p>Conclusions</p> <p>The full-length cDNA sequences obtained in this study will be essential for the ongoing annotation of the <it>Thellungiella </it>genome, especially for further improvement of gene prediction. Moreover, they will enable us to find splicing variants such as <it>ThSOS1S </it>(AB562331).</p

Intake of Radionuclides in the Trees of Fukushima Forests 3. Removal of Radiocesium from Stem Wood, Cryptomeria Japonica (L.f.) D. Don.

Nuclear power plant accidents have dispersed radiocesium into the atmosphere to contaminate trees with no turnover in heartwood, as occurred in Fukushima, and as has persisted for over 30 years around Chernobyl. Here we employ the ponding method, in which radiocesium can be flushed out from the cross-cut edges of Japanese cedar, Cryptomeria japonica (L.f.) D. Don., stem with water due to xyloglucan degradation in tracheids. Furthermore, lab-scale ponding experiments have shown that a non-detectable level of radiocesium has been observed not only in the pool water used for 575 days but also in the water containing recombinant xyloglucanase. This traditional technology is now a new biotechnology

Intake of Radionuclides in the Trees of Fukushima Forests 4. Binding of Radioiodine to Xyloglucan

The 1, 4-linked glucans such as xyloglucan and amylose are known to form a complex with iodine/iodide ions and to also be precipitated with CaCl2 in the presence of iodine. Here, we show that iodine gas could be specifically incorporated into xyloglucan. Furthermore, we show that [125I]I2 gas is, over time, incorporated at high levels into the entire outer surface of poplar seedlings but that spraying seedlings with abscisic acid to close stomata decreases the incorporation of the gas. There was less incorporation of the gas in a transgenic poplar overexpressing xyloglucanase at the early stages when compared with a wild type. This shows that xyloglucan serves as a key absorber of iodine gas into a plant body. After individual leaves of cultured seedlings were exposed to the gas for 30 min, no radioiodine was emitted from those leaves over the following two weeks, indicating that no turnover occurs in radioiodine once it is bound to the polysaccharides in plant tissues. We conclude that forest trees could serve as one of the largest enormous capture systems for the radioiodine fallout following the nuclear power plant accident in Fukushima

Mutations in nuclear pore complex promote osmotolerance in Arabidopsis by suppressing the nuclear translocation of ACQOS and its osmotically induced immunity

We have previously reported a wide variation in salt tolerance among Arabidopsis thaliana accessions and identified ACQOS, encoding a nucleotide-binding leucine-rich repeat (NLR) protein, as the causal gene responsible for the disturbance of acquired osmotolerance induced after mild salt stress. ACQOS is conserved among Arabidopsis osmosensitive accessions, including Col-0. In response to osmotic stress, it induces detrimental autoimmunity, resulting in suppression of osmotolerance, but how ACQOS triggers autoimmunity remains unclear. Here, we screened acquired osmotolerance (aot) mutants from EMS-mutagenized Col-0 seeds and isolated the aot19 mutant. In comparison with the wild type (WT), this mutant had acquired osmotolerance and decreased expression levels of pathogenesis-related genes. It had a mutation in a splicing acceptor site in NUCLEOPORIN 85 (NUP85), which encodes a component of the nuclear pore complex. A mutant with a T-DNA insertion in NUP85 acquired osmotolerance similar to aot19. The WT gene complemented the osmotolerant phenotype of aot19. We evaluated the acquired osmotolerance of five nup mutants of outer-ring NUPs and found that nup96, nup107, and aot19/nup85, but not nup43 or nup133, showed acquired osmotolerance. We examined the subcellular localization of the GFP–ACQOS protein and found that its nuclear translocation in response to osmotic stress was suppressed in aot19. We suggest that NUP85 is essential for the nuclear translocation of ACQOS, and the loss-of-function mutation of NUP85 results in acquired osmotolerance by suppressing ACQOS-induced autoimmunity in response to osmotic stress

シカクマメシュシ セイジュクキ ニ オケルABI3/VP166オ キモトリプシンインヒビターイデンシ ノ ハツゲン ニ オケルBZIPガタ テンシャインシ ノ カンヨ

ABI3/VP1はABA応答配列あるいは保存されたRY配列を介して,植物の種子成熟において多くの遺伝子発現制御を行う重要な転写因子である。シカクマメKunitz型キモトリプシンインヒビター(WCI)遺伝子の時期および器官特異的な遺伝子発現制御の解析から,我々はRY配列がWCI遺伝子の発現制御に必須ではあるが十分ではないことを示した。本研究では,シカクマメからABI3/VP1様のタンパク質(WbABI3)とbZIP型転写因子をクローニングし,これらの因子がWCI遺伝子の発現制御に関与しているか調査した。推定されるアミノ酸配列の解析から,このbZIP型転写因子(WbZIP1)は,インゲンマメにおけるABI3/VP1を介した種子タンパク質遺伝子の転写活性化を抑制する転写因子ROM2と高い相同性を示すことが明らかとなった。大腸菌を用いて発現させた組換えWbZIPタンパク質を用いたゲルシフト解析から,このタンパク質はWCI-3遺伝子プロモーターの5′-ACGT-3′を含むDNA断片に結合することが示された。ノザンブロット解析を行なったところ,WCI-3とWbABI3のmRNAが一過的に蓄積する種子成熟中期の後に,WbZIP1 mRNAの蓄積が増えることが明らかとなった。これらの結果から,WbABI3とWbZIP1はそれぞれ正の制御因子および負の制御因子として,WCI遺伝子の種子成熟中期から後期にかけての一過的な発現を制御していることが考えられた。ABI3/VP1 is an important transcription factor, which regulates the expression of many kinds of genes during plant embryo maturation via ABA responsive elements or conserved RY repeats. The RY repeats are frequently found in 5\u27 upstream regions of seed-specific genes. Through an extensive study of temporally- and spatially-regulated expression of a winged bean chymotrypsin inhibitor (WCI) gene, we have demonstrated that the RY repeat is necessary but not sufficient for the seed-specific expression. In this study, we have cloned cDNAs encoding an ABI3/VP1 like factor (WbABI3) and a bZIP DNA binding protein from winged bean to investigate the participation of ABI3/VP1 and bZIP-type transcription factors in WCI gene expression. The deduced protein sequence of the bZIP protein (WbZIP1) was highly homologous to ROM2, which is shown to be a repressor against ABI3/VP1-activated transcription of MAT class genes during late-seed maturation in French bean. Bacterial recombinant WbZIP1 protein was prepared and tested in a gel mobility shift assay to verify its binding to the promoter region of the WCI-3 gene, which encodes a major WCI protein of winged bean. The recombinant WbZIP1 protein proved to show a high affinity for specific fragments containing 5\u27-ACGT-3\u27 sequences from the WCI-3 promoter. Enhanced expression of the WbZIP1 gene was observed during late-stage seed maturation after the transient expression of WCI-3 and WbABI3 in mid-stage seed maturation. These results suggest that WbABI3 and WbZIP1 may function antagonisitically to tune the level of WCI gene expression from mid- through late-stage seed maturation in winged bean

Dissecting the genetic control of natural variation in salt tolerance of Arabidopsis thaliana accessions

Many accessions (ecotypes) of Arabidopsis have been collected. Although few differences exist among their nucleotide sequences, these subtle differences induce large genetic variation in phenotypic traits such as stress tolerance and flowering time. To understand the natural variability in salt tolerance, large-scale soil pot experiments were performed to evaluate salt tolerance among 350 Arabidopsis thaliana accessions. The evaluation revealed a wide variation in the salt tolerance among accessions. Several accessions, including Bu-5, Bur-0, Ll-1, Wl-0, and Zu-0, exhibited marked stress tolerance compared with a salt-sensitive experimental accession, Col-0. The salt-tolerant accessions were also evaluated by agar plate assays. The data obtained by the large-scale assay correlated well with the results of a salt acclimation (SA) assay, in which plants were transferred to high-salinity medium following placement on moderate-salinity medium for 7 d. Genetic analyses indicated that the salt tolerance without SA is a quantitative trait under polygenic control, whereas salt tolerance with SA is regulated by a single gene located on chromosome 5 that is common among the markedly salt-tolerant accessions. These results provide important information for understanding the mechanisms underlying natural variation of salt tolerance in Arabidopsis

エキジョウカ オ キョヨウ シタ カイリョウガタ チョクセツ キソ ノ セッケイホウ ニカンスル ケンキュウ

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