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This study describes the: (1) morphological nature of the calcites in the Toki granite, central Japan; (2) the difference in chemical compositions in terms of morphological classification; and (3) the identification of the stages of calcite formation and the corresponding mass transfer between minerals and fluid owing to hydrothermal alterations and groundwater-rock interactions, which reveals the sequential variations in fluid chemistry during the sub-solidus stage. Calcites in the Toki granite were classified into four types: (1) lenticular calcite in the chloritized biotite; (2) granular calcite in the altered plagioclase; (3) intergranular calcite; and (4) fracture-filling calcite. The lenticular, granular, and intergranular calcites contain greater amounts of iron, manganese, and magnesium than fracture-filling calcites. The lenticular calcite in the chloritized biotite, granular calcite in the altered plagioclase, and intergranular calcite formed due to the precipitation of calcium, iron, manganese, and magnesium released from biotite and plagioclase owing to hydrothermal alterations. The fracture-filling calcites formed at a later stage than the lenticular, granular, and intergranular forms. In the hydrothermal fluid, the concentrations of aluminum, iron, manganese, and magnesium gradually decrease, and the concentration of calcium gradually increases as the alteration proceeds. The chemical characteristics of the fluid at the late stage of hydrothermal alteration and those of the subsequent groundwater are consistent with those of fracture-filling calcites, indicating that the fracture-filling calcites precipitated from the fluid at a late stage of hydrothermal alterations and then from the groundwater. Elements released from biotite and plagioclase owing to hydrothermal alterations were incorporated into and fastened to the calcite. Therefore, the calcites influenced the sequential variations in fluid chemistry during the sub-solidus stage.

For the first time, cathodoluminescence (CL) was used to show oscillatory zoning in perthitic K‑feldspars from the equigranular Toki granite, central Japan. Based on the CL patterns, two types of zoning are identified: single core oscillatory zoning (SCOZ) and multiple core oscillatory zoning (MCOZ). The SCOZ is defined by oscillatory zoning around a single-crystal core within the K‑feldspar crystal, whereas the MCOZ depicts two or more such crystal cores. The crystal cores displayed in CL images reflect the nucleation parts of magmatic K‑feldspar. The existence of MCOZ patterns in K‑feldspars indicates multiple nuclei. CL patterns reveal crystal growth behavior of magmatic K‑feldspar in the equigranular Toki granite. CL intensities are positively correlated with titanium and barium concentrations, indicating that the CL variations depend on two factors: (1) titanium concentration as a CL activator and (2) density of Al-O−-Al structural defects. The analysis of CL images revealed that albite-rich phases in microperthite and patchperthite with low-luminescence intensities cut across the CL bands of the oscillatory zoning, indicating that the oscillatory zoning in the orthoclase-rich host phase of K‑feldspar was not perturbed by the formation of microperthite and patchperthite in the post-crystallization stage. The luminescence intensities of albite-rich phases in patchperthite are lower than those in microperthite, which is due to the diferences in titanium and barium concentrations between them. In the post-crystallization stage, the mass transfer of titanium and barium occurred during the formation of microperthite and patchperthite. Therefore, the diference in the luminescence intensities between microperthite and patchperthite lamellae reflects their diferent formation mechanisms between exsolution coarsening and dissolution-precipitation coarsening. In summary, CL analyses can be used for the evaluation of the nucleation and growth not only of anhedral K‑feldspar crystals in equigranular granite but also of K‑feldspar phenocrysts/megacrysts in porphyritic granite. It can reveal the spatial extent of element partitioning between the melt and crystal, along with that of mass transfer from the melt into crystals during the magma evolution. Moreover, the CL analyses can also be used for the interpretation of K‑feldspar textural development during the post-crystallization stage.

The formation process of myrmekites in granitic rocks can help us to understand the mass transfer between minerals and hydrothermal fluids during the deuteric stage. The Toki granite, central Japan, has three types of myrmekites. Type A myrmekite is defined as a single layer. Type B myrmekite shows a composite texture consisting of two layers, namely, a myrmekite layer and an albite (Ab)-rich layer that is free of vermicular quartz. Type C has a composite texture with the following three layers: two myrmekite layers separated by one Ab-rich layer. Micropores are found in these myrmekites in the undeformed granite, which enable quantitative determinations of the volume decrease during myrmekite formation by measurement of the area of micropores. The areal relationship between the micropores and vermicular quartz in the myrmekites exhibited a high correlation (R2= 0.8352), thus indicating that the genesis of the micropores is evidently related to myrmekite formation. We derived the reaction equations for myrmekite formation based on the singular value decomposition method. The matrices for singular value decomposition involve the following volume factors: volume change during the reaction and volume ratios of the product minerals. The singular value decomposition indicates that the myrmekites are produced through the consumption of plagioclase and K-feldspar with an inflow of H4SiO4, Na+, and H+from the hydrothermal fluid, accompanied by an outflow of Al3+, Ca2+, and K+into the fluid, which constitute essential mass transfers during myrmekite formation. The diference of pH in the hydrothermal fluid and inflow amounts of H4SiO4and Na+can explain the reason why micropores occur in the myrmekites but not in the Ab-rich rim (layer); the smaller inflow of H4SiO4and Na+from the hydrothermal fluid with lower pH conditions yielded micropore production during myrmekitization, and the larger inflow of H4SiO4and Na+from the hydrothermal fluid with higher pH conditions yielded the formation of the Ab-rich rim (layer) with few micropores. The sequential variations in the chemical characteristics of the hydrothermal fluid during the sub-solidus conditions were characterized by a gradual decrease in H4SiO4(Si4+), Fe2+, Mn2+, Mg2+, and Na+and a gradual increase in Ca2+, K+, H+, and F–.

Felsic magmatism in the southern part of Himachal Higher Himalaya is constituted by Neoproterozoic granite gneiss (GGn), Early Palaeozoic granitoids (EPG) and Tertiary tourmaline-bearing leucogranite (TLg). Magnetic susceptibility values (<3 ×10−3SI), molar Al2O3/(CaO + Na2O+ K2O) (≥1.1), mineral assemblage (bt–ms–pl–kf–qtz ± tur ± ap), and the presence of normative corundum relate these granitoids to peraluminous S-type, ilmenite series (reduced type) granites formed in a syncollisional tectonic setting. Plagioclase from GGn (An10–An31) and EPG (An15–An33) represents oligoclase to andesine and TLg (An2–An15) represents albite to oligoclase, whereas compositional ranges of K-feldspar are more-or-less similar (Or88to Or95in GGn, Or86to Or97in EPG and Or87to Or94in TLg). Biotites in GGn (Mg/Mg + Fet= 0.34–0.45), EPG (Mg/Mg + Fet= 0.27–0.47), and TLg (Mg/Mg + Fet= 0.25–0.30) are ferribiotitesenriched in siderophyllite, which stabilised between FMQ and HM buffers and are characterised by dominant 3Fe ⇌ $\rightleftharpoons $2Al, 3Mg ⇌ $\rightleftharpoons $2Al substitutions typical of peraluminous (S-type), reducing felsic melts. Muscovite in GGn (Mg/Mg + Fet=0.58–0.66), EPG (Mg/Mg + Fet=0.31−0.59), and TLg (Mg/Mg + Fet=0.29–0.42) represent celadoniteand paragonitesolid solutions, and the tourmaline from EPG and TLg belongs to the schorl-elbaiteseries, which are characteristics of peraluminous, Li-poor, biotite-tourmaline granites. Geochemical features reveal that the GGn and EPG precursor melts were most likely derived from melting of biotite-rich metapelite and metagraywacke sources, whereas TLg melt appears to have formed from biotite-muscovite rich metapelite and metagraywacke sources. Major and trace elements modelling suggest that the GGn, EPG and TLg parental melts have experienced low degrees (∼13, ∼17 and ∼13%, respectively) of kf–pl–bt fractionation, respectively, subsequent to partial melting. The GGn and EPG melts are the results of a pre-Himalayan, syn-collisional Pan-African felsic magmatic event, whereas the TLg is a magmatic product of Himalayan collision tectonics.

Southwest Japan rotated clockwise during the late stage of the opening of the Japan Sea, although the exact timing of the rotation is controversial. A recent biostratigraphic study has revealed that the Miocene Oidawara Formation in eastern Southwest Japan was deposited just before 15 Ma; consequently, its paleomagnetic direction may help constrain the timing of rotation. For this purpose, we collected fine felsic tuffs and siltstones at 71 stratigraphic sites (horizons) in the Oidawara Formation. An analysis of alternating field and thermal demagnetization results yielded characteristic remanent magnetization (ChRM) directions for 177 samples. Approximately 80 % (142) of the samples exhibit reverse polarity ChRM directions that are thought to be paleofield directions of reverse polarity Chron C5Br. Normal polarity ChRM directions in 35 samples include primary paleofield records as well as records of secondary magnetization. The data suggest that a short normal polarity interval (microchron or cryptochron) at ~15.8 Ma is present within the dominantly reverse polarity interval of Chron C5Br. Reliable site-mean directions for 19 sites yield a tilt-corrected formation-mean direction of D= 10.5°, I= 41.1°, α95= 7.0°, and k= 23.9, indicating virtually no rotation with respect to a reference paleomagnetic direction for the Asian continent. A rotation versus age plot for Southwest Japan indicates that the clockwise rotation started after 17.5 Ma and ceased largely before 15.8 Ma, yielding a rotation rate of ~23°/Myr.

ABSTRACTDifferent abiotic stresses induce OsTZF1, a tandem CCCH-type zinc finger domain gene, in rice. Here, we report that transgenic rice plants overexpressing OsTZF1under own promoter (POsTZF1:OsTZF1-OX [for overexpression]) transferred to soil showed normal growth similar to vector control plants. The POsTZF1:OsTZF1-OX produced normal leaves without any lesion mimic phenotype and exhibited normal seed setting. The POsTZF1:OsTZF1-OX plants showed significantly increased tolerance to salt and drought stresses and enhanced post stress recovery. Microarray analysis revealed a total of 846 genes up-regulated and 360 genes down-regulated in POsTZF1:OsTZF1-OX salt-treated plants. Microarray analysis of POsTZF1:OsTZF1-OX plants showed the regulation of many abiotic stress tolerance genes. These results suggest that OsTZF1-OX under own promoter show abiotic stress tolerance and produces no pleiotropic effect on phenotype of transgenic rice plant.

The crystal chemistry of the rare sulfosalt makovickyite from the Obari mine, Yamagata Prefecture, Japan was studied with electron-microprobe analysis (EMPA), and single-crystal X-ray diffraction methods. The chemical composition of the studied crystal is (Cu1.26Ag0.62Pb0.16Bi5.09Sb0.01)S7.13(S8.95Se0.04Te0.01)S9.00 normalized to S(S+Se+Te) = 9 (Z = 2). The structure of this makovickyite (a = 13.2524(5), b = 4.0523(2), c = 14.6775(6) Å, b = 99.487(3)°, V = 777.44(4) Å3, space group C2/m) was refined to R 1 = 4.31 %. Makovickyite, the 4P member of the pavonite homologues, is composed of alternating thick layers of Bi1S6 and Bi2S6 octahedra, and thin layers of Bi3S7 polyhedra alternating with low occupied interstitial tetrahedrally coordinated sub-sites, Cu1, Cu2, Cu3 and Cu3A (in this study). In makovickyite sensu stricto the thin layer also contains a partially occupied octahedral AgS6 site, which was found to be empty in Obari makovickyite. Thus, it is considered a Cu isotype of makovickyite sensu stricto, ideally Ag1.5Bi5.5S9, because the Cu isotype has no significant Ag in the thin layer. The arrangement of the Cu1, Cu2, Cu3, and Cu3A sub-sites is similar as determined for Cu3.21Bi4.79S9, a synthetic 4 P pavonite analogue. The structure of the investigated crystal has 0.5 Ag pfu replacing Bi in the thick layer at Bi1 with the remaining Ag at Bi2.

The crystal chemistry of Ti-rich ferriallanite-(Ce) in syenites from Cape Ashizuri, Shikoku Island, Japan, was studied using electron microprobe analysis (EMPA) and single-crystal X‑ray diffraction methods. Our specimens (AS001 and AS304) are characterized by high-Ti (-3.6 wt% TiO2) and Fe contents (-21.3 wt% FeO*; Fe2+/total Fe = 0.6-0.7). Structure refinements of two ferriallanite-(Ce) crystals converged to R1 = 1.50-1.57%. In both specimens, the dominant cations at A1, A2, and M3 are Ca, Ce, and Fe2+, respectively. However, depending on Ti assignment, two different schemes of the cation distributions at M1 and M2 can be considered: (1) (Fe0.72Ti0.23Al0.05)M1(Al0.82Fe3+0.18)M2 and (2) (Fe0.90Al0.10)M1(Al0.77Ti0.23)M2 for AS001, and (1) (Fe0.65Ti0.29Al0.06)M1(Al0.89Fe3+0.11)M2 and (2) (Fe0.76Ti0.13Al0.11)M1(Al0.84Ti0.16)M2 for AS304. The Si2O7group is compressed along Sil-O9-Si2 direction because of the expansions of the M1O6 and M3O6 octahedra due to substitution of large octahedral cations for Al. This compression is monitored by the atom position of O9 that shifts away from the cation at A1 decreasing the Si1-O9-Si2 angle. In allanite-subgroup minerals, the A1-O9 distance is longer and the bridging angle is smaller than those of clinozoisite-subgroup minerals. Although the A1 polyhedron is generally described as a ninefold-coordinated site, it is appropriately described as sevenfold-coordinated in Ti-rich allanite-(Ce) because of the lengthened A1-O9 (×2) distance. The cation substitutions at M1 and M3 indirectly affect the topology of the A1 polyhedron.

ABA-responsive elements (ABREs) are cis-acting elements and basic leucine zipper (bZIP)-type ABRE-binding proteins (AREBs) are transcriptional activators that function in the expression of RD29Bin vegetative tissue of Arabidopsisin response to abscisic acid (ABA) treatment. Dehydration-responsive elements (DREs) function as coupling elements of ABRE in the expression of RD29Ain response to ABA. Expression analysis using abi3and abi5mutants showed that ABI3 and ABI5 play important roles in the expression of RD29Bin seeds. Base-substitution analysis showed that two ABREs function strongly and one ABRE coupled with DRE functions weakly in the expression of RD29Ain embryos. In a transient transactivation experiment, ABI3, ABI5 and AREB1 activated transcription of a GUSreporter gene driven by the RD29Bpromoter strongly but these proteins activated the transcription driven by the RD29Apromoter weakly. In 35S::ABI3 Arabidopsisplants, the expression of RD29Bwas up-regulated strongly, but that of RD29Awas up-regulated weakly. These results indicate that the expression of RD29Bhaving ABREs in the promoter is up-regulated strongly by ABI3, whereas that of RD29Ahaving one ABRE coupled with DREs in the promoter is up-regulated weakly by ABI3. We compared the expression of 7000 Arabidopsisgenes in response to ABA treatment during germination and in the vegetative growth stage, and that in 35S::ABI3plants using a full-length cDNA microarray. The expression of ABI3- and/or ABA-responsive genes and cis-elements in the promoters are discussed.ABA-responsive elements (ABREs) are cis-acting elements and basic leucine zipper (bZIP)-type ABRE-binding proteins (AREBs) are transcriptional activators that function in the expression of RD29Bin vegetative tissue of Arabidopsisin response to abscisic acid (ABA) treatment. Dehydration-responsive elements (DREs) function as coupling elements of ABRE in the expression of RD29Ain response to ABA. Expression analysis using abi3and abi5mutants showed that ABI3 and ABI5 play important roles in the expression of RD29Bin seeds. Base-substitution analysis showed that two ABREs function strongly and one ABRE coupled with DRE functions weakly in the expression of RD29Ain embryos. In a transient transactivation experiment, ABI3, ABI5 and AREB1 activated transcription of a GUSreporter gene driven by the RD29Bpromoter strongly but these proteins activated the transcription driven by the RD29Apromoter weakly. In 35S::ABI3 Arabidopsisplants, the expression of RD29Bwas up-regulated strongly, but that of RD29Awas up-regulated weakly. These results indicate that the expression of RD29Bhaving ABREs in the promoter is up-regulated strongly by ABI3, whereas that of RD29Ahaving one ABRE coupled with DREs in the promoter is up-regulated weakly by ABI3. We compared the expression of 7000 Arabidopsisgenes in response to ABA treatment during germination and in the vegetative growth stage, and that in 35S::ABI3plants using a full-length cDNA microarray. The expression of ABI3- and/or ABA-responsive genes and cis-elements in the promoters are discussed.

Abstract. Many granitic plutons of Early Cretaceous age are intruded on various scales in the Kitakami Mountains. The stock‐type Ganidake pluton accompanies enormous Fe‐Cu mineralization of the Kamaishi deposits, whereas the Kurihashi pluton accompanies less mineralization. To elucidate the cause of these differences, the metamorphic conditions and redox state of the contact metamorphic aureole around the Kurihashi pluton have been examined by the petrochemical study and gas analysis of the metamorphic rocks.

Pyrophanite and high Mn ilmenite have been discovered in the Tono plutonic rocks of Kitakami Mountains, NE Japan. The rocks in the pluton are classified into four rock facies; Marginal, Main, Arakawa-type and Central facies. The former three facies which are composed of quartzdiorite and granodiorite are believed to represent a series of continuous differentiation and the last facies, composed of tonalite and granodiorite, is similar but slightly different from the above differentiation. Magnetite, ilmenite and hematite are present in these rock facies, although ilmenite is absent in the Arakawa-type facies. Manganese content of ilmenite increases from the Marginal facies to the Main facies as differentiation proceeds. Especially, in the Central facies, the highest MnO content of 35 wt.% (74 mol. % MnTiO3) was detected in a composite-type ilmenite which exsolved hematite. This is the maximum value that has ever been reported from calc?alkaline igneous rocks, except for pegmatite. The presence of euhedral discrete hematite, myrmekite, euhedral biotite and intergranular muscovite in the Central facies, and an equilibrium temperature obtained by a two-feldspar geothermometer, show that crystallization of the Tono granitic magma continued to a low-temperature subsolidus stage under volatile-rich highly oxidized conditions. The pyrophanite crystallized in the greatly differentiated facies which solidified from an intrinsically volatile-rich magma.

: We aimed to improve the purification of citrus Huanglongbing (greening) bacterium (HB), Candidatus Liberobacter asiaticum and to produce an antiserum against HB. Periwinkle plants Catharantus roseum L. graft-inoculated with HB were used to produce an antiserum. All young leaves of new shoots incubated at 20–25°C and 25–30°C, a few mature leaves incubated at 20–25°C, and all mature leaves incubated first at 25–30°C and later transferred to 20–25°C developed yellowing symptoms and were then used to prepare immunogen. The HB was partially purified from these leaves by an improved method that included a macerating enzyme treatment of the midribs of infected leaves and homogenization of infected phloem sieve tissues. An antiserum raised against partially purified HB reacted clearly at a dilution of 1/16 with HB-infected citrus extract prepared at a concentration of 40 times, but did not react with healthy or tristeza virus-infected citrus extract in microprecipitin tests.

Proline (Pro) is one of the most widely distributed osmolytes in water-stressed plants. We previously isolated from Arabidopsis a gene encoding Pro dehydrogenase (ProDH), a mitochondrial enzyme involved in the first step of the conversion of Pro to glutamic acid. The ProDH gene in Arabidopsis is up-regulated by rehydration after dehydration but is down-regulated by dehydration. ProDH is also induced by L-Pro and hypoosmolarity. The induction of ProDH expression under rehydration seems to be caused by both accumulated Pro and hypoosmolarity. We analyzed a DNA region that is located 5' to the transcription start site (a promoter region) of ProDH to identify cis-acting elements involved in L-Pro-induced and hypoosmolarity-induced expression in transgenic tobacco (Nicotiana tabacum) and Arabidopsis plants. We found that a 9-bp sequence, ACTCATCCT, in the ProDH promoter is necessary for the efficient expression of ProDH in response to L-Pro and hypoosmolarity. Moreover, ACTCAT is a core cis-acting element, which we have called Pro- or hypoosmolarity-responsive element (PRE), that is necessary for L-Pro-responsive and hypoosmolarity-responsive expression of ProDH. Microarray and RNA gel-blot analyses showed that 21 L-Pro-inducible genes have the PRE sequences in their promoter regions. These results indicate that the PRE sequence play an important role in the L-Pro-responsive gene expression.

Abstract: The North granitic body of the Miyako pluton is located in the Northern Kitakami belt, Northeast Japan. The formation of the scheelite–chalcopyrite–magnetite–bearing aplitic veins and scheelite–chalcopyrite–magnetite–bearing Yamaguchi skarn deposit was closely associated with the formation of the Miyako plutons. Petrographic facies of the North granitic body vary from quartz diorite in marginal zone (zone A), to tonalite and granodiorite (zone B), and to granite (zone C) in the central. The large numbers of aplitic veins distributed around the Yamaguchi mining area are divided into two groups: barren and scheelite–mag–netite–chalcopyrite–bearing aplitic veins. The latter cut massive clinopyroxene skarns of the Yamaguchi deposit, and are composed of plagioclase, K‐feldspar and titanite. Some plagioclase crystals have dusty cores with irregularly shaped K‐feldspar flakes, and clear rims of albite. Textures of plagioclase in the mineralized aplitic veins are different from the idiomorphic textures with sharp plagioclase crystal boundaries that occur in the North granitic body and barren aplitic veins. These textural data suggest that the mineralized aplitic veins were formed from hydrothermal fluid.

Abstract: Crystallinity, chemical compositions and K‐Ar ages of sericites in highly‐sericitized granites and associated fissure‐filling veins were examined to delineate the timing and duration of the hydrothermal activity in the Oligocene Hamada cauldron in the San‐in district, SW Japan. Sericite separates (>2 μm) from the highly‐sericitized granites consist mainly of 2M1polytype having high crystallinity and low Kübler indices of 0.22–0.35, while those in the fissure‐filling veins have lower 2M1/1Md ratios and crystallinity, and high Kübler indices of 0.29–0.35. This suggests that the sericites in highlysericitized granites were formed at a higher temperature than the vein sericites.

In plants, a cis-acting element, DRE/CRT, is involved in ABA-independent gene expression in response to dehydration and low-temperature stress. To understand signal transduction pathways from perception of the dehydration stress signal to gene expression, we characterized a gene family for DRE/CRT-binding proteins DREB2A and DREB2B in Arabidopsis thaliana. Northern analysis showed that both genes are induced by dehydration and high-salt stress. Organ-specific northern analysis with gene-specific probes showed that these genes are strongly induced in roots by high-salt stress and in stems and roots by dehydration stress. The DREB2Agene is located on chromosome 5, and DREB2Bon chromosome 3. We screened an Arabidopsisgenomic DNA library with cDNA fragments of DREB2Aand DREB2Bas probes, and isolated DNA fragments that contained 5′-flanking regions of these genes. Sequence analysis showed that both genes are interrupted by a single intron at identical positions in their leader sequence. Several conserved sequences were found in the promoter regions of both genes. The β-glucuronidase (GUS) reporter gene driven by the DREB2promoters was induced by dehydration and high-salt stress in transgenic Arabidopsisplants.

Chevkinite has been found in Miocene syenites of Cape Ashizuri, Shikoku Island, Southwest Japan. The non-metamict crystallinity of this mineral gives definitive X-ray data on unheated material. The unit cell parameters obtained are a = 13.461(26), b = 5.676(9), c = 11.352(14)Å, ß = 100.86(10)°, which give a cell volume of 851.8 Å3. For Z = 2, Dcalc = 4.88 g/cm3. Electron microprobe analyses of chevkinite show little variation in composition within and among grains and yield the following empirical formula based on 22 oxygens: (Ce1.685La1.005Ca.694Nd.298 Th.229Y.061Eu.016Dy.012) 𝛴4.00(Ti2.402Fe2.068Nb.381Mg.090Ca.065, Mn.041)𝛴5.05Si4.07O22. The mineral is notably enriched in LREEs, Nb and Th. This is the first reported occurrence of chevkinite in Japan.

Abstract: Plants respond and adapt to environmental changes including drought, high salinity and low temperature. abscisic acid (ABA) plays important roles in these stress responses. A number of plant genes are induced by water stress, such as drought, high salinity and low temperature, and are thought to function in the stress tolerance and responses of the plant. At least four signal transduction pathways control these genes inArabidopsis thaliana: two are ABA-dependent, and two are ABA-independent. Acis-acting element named DRE (Dehydration Responsive Element) is involved in one of the ABA-independent signal transduction pathways, and its DNA binding proteins have been characterized. Drought- and ABA-inducible MYC and MYB homologues are involved in ABA-responsive gene expression inarabidopsis. Roles of thesecis andtrans-acting factors in water stress responses are discussed. In addition, a number of genes for protein kinases, enzymes involved in phosphatidyl inositol metabolism (PI turnover) and transcription factors are also induced by water stress, and thought to be involved in the stress signal transduction cascades. Possible signaling processes in water stress response are discussed.

In higher plants, acis-acting element, DRE/CRT, is involved in gene expression responsive to drought and low-temperature stress. To understand signal transduction pathways from the cold stress signal to gene expression, we characterized a gene family for DRE/CRT-binding proteins DREB1A and CBF1 inArabidopsis thaliana.DREB1A and CBF1 were shown to be involved in low-temperature-responsive gene expression. We screened anArabidopsisgenomic DNA library with the cDNA fragment of DREB1A as a probe and isolatedDREB1Aand 2 related genes,DREB1B(= CBF1) andDREB1C.These were arrayed in the order B, A, C in an 8.7 kb region ofArabidopsischromosome 4. Northern blot analysis using gene-specific probes showed that the 3DREB1genes are induced mainly by cold stress but not by osmotic stress in leaves, roots, and stems. Several conserved sequences were found in the promoter regions of all 3 genes. The β-glucuronidase (GUS) reporter gene driven by theDREB1promoters was induced at transcriptional level by low temperature in transgenicArabidopsisplants.

The 105-kDa heat shock protein (HSP105) is a member of the high-molecular-mass heat shock protein family. We have isolated and characterized the mouse HSP105 gene including about 1.2 kb of the 5′-flanking region. The mouse HSP105 gene spans about 22 kb, consisting of 18 exons separated by 17 introns. Southern blotting analysis revealed the existence of a single copy of HSP105. Primer extension analysis revealed that the transcription initiation site was located 165 bp upstream of the ATG translation initiation codon. The 5′-promoter region of the HSP105 gene contained a TATA box, a CAAT box, an inverted CAAT box, and two GC boxes. Two heat shock element (HSE) sequences were found as four nGAAn repeats at nt −64 and nt −128. Promoter analysis using deletion derivatives revealed that a minimal region which contained the two consensus HSE sequences was active in response to heat shock and also for constitutive expression of the gene.

A cDNA, ERD1, isolated from one‐hour‐dehydrated plants of Arabidopsis thalianaL. encodes a putative protein that is similar to the regulatory ATPase subunit (ClpA) of the Clp protease and contains a putative chloroplast‐targeting transit‐peptide at the N‐terminus. A chimeric gene with the putative plastid‐targeting sequence of the erd1gene fused to the synthetic green‐fluorescent protein (sGFP) gene was constructed and introduced into Arabidopsisprotoplasts. The N‐terminal region of the ERD1 protein directed the sGFP protein into the plastids of the protoplasts, and functioned as a transit peptide. Northern blot analysis indicated that expression of the erd1gene was induced not only by water stress, such as dehydration and high salinity, but also by natural senescence and dark‐induced etiolation. The erd1gene was not strongly induced by exogenous abscisic acid. A chimeric gene with the 0.9 kb promoter region of the erd1gene fused to the β‐glucuronidase (GUS) reporter gene was constructed, and tobacco plants transformed with the construct. The GUS reporter gene driven by the erd1promoter was induced by dehydration and high salt stress at significant levels in the transgenic plants. The GUS gene was strongly expressed in older leaves without dehydration, and was induced by dark‐induced etiolation. Furthermore, GUS activity was reduced by cytokinin treatment during dark‐induced etiolation. These results indicate that expression of the erd1gene is developmentally up‐regulated by senescence as well as by water stress.

•Soybean plants overexpressing NCEDare more sensitive to waterlogging than the WT plants•NCEDoverexpression increased oxidative stress in soybean plants exposed to waterlogging and reoxygenation•NCEDoverexpression decreased fermentation in soybean plants exposed to waterlogging•NCEDoverexpression reduced seed weight and yield in soybean plants exposed to waterlogging