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The structural characterization at the interfaces of CuPc/TiO(x) heteromultilayers manufactured by evaporation reveals new information on optoelectronic materials. The characterization is performed by secondary ion mass spectroscopy (SIMS) and x-ray diffraction methods. The characterization reveals the presence of well-defined alternating layered structure consisting of inorganic and organic materials.

The transition from vegetative to reproductive growth is marked by the termination of vegetative development and adoption of a floral identity by the shoot apical meristem. This process is called the floral transition. To elucidate the molecular determinants involved in this process in chrysanthemum (Chrysanthemum morifolium Ramat.), we isolated the following three floral identity and/or integrator genes from plants: CmFL, a homologue of FLORICAULA (FLO)/LEAFY (LFY); CmAFL1, a member of the APETALA1 (AP1)/FRUITFULL (FUL) sub-family; and CmSOC1, a member of the SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) sub-family. Up-regulated expression of CmFL in Arabidopsis resulted in an early-flowering phenotype. Our data show significant up-regulation of expression of all three of the above-mentioned genes and a strong correlation between the floral transition and gene expression under three different photoperiodic conditions. This study strongly suggests that CmFL, CmAFL1, and CmSOC1 are involved in the transition from vegetative to reproductive growth, and are activated co-ordinately after the floral transition in early-developing inflorescences in chrysanthemum. [ABSTRACT FROM AUTHOR]

Heat-induced rosetted Eustoma grandiflorum requires low temperature for induction of stem elongation and flowering. Although heat-induced rosetting is associated with a reduction of gibberellin A1 (GA1) content, how thermo-induction affects GA biosynthesis is unclear. Thus, we examined levels of GA, precursors including that of ent-kaurene which is the first committed step in GA biosynthesis. We used uniconazole, an ent-kaurene oxidase inhibitor to estimate the ent-kaurene biosynthesis activity. The accumulation level of ent-kaurene in stems of the cold-treated seedlings was approximately 1.8 times that of the non-cold-treated seedlings, whereas no difference was observed in the leaves. No change was observed in endogenous levels of GA1 and GA20 in stems of the heat-induced rosetted plants during the cold treatment, whereas their levels increased with stem elongation after transfer to warm conditions. In contrast to the levels of GA1 and GA20, endogenous levels of ent-kaurene, ent-kaurenoic acid, GA53, GA44 and GA19 in the stems markedly increased at the end of cold treatment. These results indicate that ent-kaurene biosynthesis and its metabolism early in the GA biosynthetic pathway are stimulated by low temperature and, later, the stimulation leads to an increment of endogenous levels of GA1 which is essential for stem elongation of the heat-induced rosetted E. grandiflorum. [ABSTRACT FROM AUTHOR]

Cultivated chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the most economically important ornamental crops grown worldwide. It has a complex hexaploid genome (2n = 6x = 54) and large genome size. The diploid Chrysanthemum seticuspe is often used as a model of cultivated chrysanthemum, since the two species are closely related. To expand our knowledge of the cultivated chrysanthemum, we here performed de novo whole-genome assembly in C. seticuspe using the Illumina sequencing platform. XMRS10, a C. seticuspe accession developed by five generations of self-crossing from a self-compatible strain, AEV2, was used for genome sequencing. The 2.72 Gb of assembled sequences (CSE_r1.0), consisting of 354,212 scaffolds, covered 89.0% of the 3.06 Gb C. seticuspe genome estimated by k-mer analysis. The N50 length of scaffolds was 44,741 bp. For protein-encoding genes, 71,057 annotated genes were deduced (CSE_r1.1_cds). Next, based on the assembled genome sequences, we performed linkage map construction, gene discovery and comparative analyses for C. seticuspe and cultivated chrysanthemum. The generated C. seticuspe linkage map revealed skewed regions in segregation on the AEV2 genome. In gene discovery analysis, candidate flowering-related genes were newly found in CSE_r1.1_cds. Moreover, single nucleotide polymorphism identification and annotation on the C. × morifolium genome showed that the C. seticuspe genome was applicable to genetic analysis in cultivated chrysanthemums. The genome sequences assembled herein are expected to contribute to future chrysanthemum studies. In addition, our approach demonstrated the usefulness of short-read genome assembly and the importance of choosing an appropriate next genome sequencing technology based on the purpose of the post-genome analysis., (© The Author(s) 2019. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.)

An ionic KBr(001) crystal surface covered with a thin water layer was observed with a frequency modulation atomic force microscope (FM-AFM) with atomic resolution. By immersing only the tip apex of the AFM cantilever in the thin water layer, the Q-factor of the cantilever in probing the solid-liquid interface can be maintained as high as that of FM-AFM operation in air, leading to improvement of the minimum detection of a differential force determined by the noise. Two types of images with atom-resolved contrast were observed, possibly owing to the different types of ions (K(+) or Br(-)) adsorbed on the tip apex that incorporated into the hydration layers on the tip and on the sample surface. The force-distance characteristics at the solid-water interface were analyzed by taking spatial variation maps of the resonant frequency shift of the AFM cantilever with the high Q-factor. The oscillatory frequency shift-distance curves exhibited atomic site dependence. The roles of hydration and the ions on the tip and on the sample surface in the measurements were discussed.

We aimed to identify the main compounds responsible for low temperature-induced yellow pigmentation of the bracts of Zantedeschia aethiopica 'Wedding March'. On the basis of the area ratios estimated from absorbance at 400 nm in HPLC analyses, we identified two flavonoids, isoorientin and swertiajaponin, as such compounds. We also identified two additional flavonoids, isovitexin and swertisin, which do not contribute considerably to the yellow pigmentation. Flavonoids of Zantedeschia bracts seem to belong to the class of flavone C-glycosides.

Five anthocyanins, delphinidin 3-O-rutinoside, cyanidin 3-O-rutinoside, petunidin 3-O-rutinoside, malvidin 3-O-glucoside and malvidin 3-O-rutinoside, were identified. Three anthocyanins, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were putatively identified based on C18 HPLC retention time, absorption spectrum, including λmax, and comparisons with those of corresponding standard anthocyanins, as the compounds responsible for the pink to purple-red pigmentation of the bracts of Curcuma alismatifolia and five related species. Cluster analysis based on four major anthocyanins formed two clusters. One consisted of only one species, C. alismatifolia, and the other consisted of five. Each cluster further formed sub-clusters depending on either species or habitats.

Gibberellins (GAs) are the plant hormones that control many aspects of plant growth and development, including stem elongation. Genes encoding enzymes related to the GA biosynthetic and metabolic pathway have been isolated and characterized in many plant species. Gibberellin 2-oxidase (GA2ox) catalyzes bioactive GAs or their immediate precursors to inactive forms; therefore, playing a direct role in determining the levels of bioactive GAs. In the present study, we produced transgenic plants of the liliaceous monocotyledon Tricyrtis sp. overexpressing the GA2ox gene from the linderniaceous dicotyledon Torenia fournieri (TfGA2ox2). All six transgenic plants exhibited dwarf phenotypes, and they could be classified into two classes according to the degree of dwarfism: three plants were moderately dwarf and three were severely dwarf. All of the transgenic plants had small or no flowers, and smaller, rounder and darker green leaves. Quantitative real-time reverse transcription-polymerase chain reaction (PCR) analysis showed that the TfGA2ox2 expression level generally correlated with the degree of dwarfism. The endogenous levels of bioactive GAs, GA1 and GA4, largely decreased in transgenic plants as shown by liquid chromatography-mass spectrometry (LC-MS) analysis, and the level also correlated with the degree of dwarfism. Exogenous treatment of transgenic plants with gibberellic acid (GA3) resulted in an increased shoot length, indicating that the GA signaling pathway might normally function in transgenic plants. Thus, morphological changes in transgenic plants may result from a decrease in the endogenous levels of bioactive GAs. Finally, a possibility of molecular breeding for plant form alteration in liliaceous ornamental plants by genetically engineering the GA metabolic pathway is discussed., (Copyright © 2013 Elsevier GmbH. All rights reserved.)

Immature pumpkin (Cucurbita maxima) seeds contain gibberellin (GA) oxidases with unique catalytic properties resulting in GAs of unknown function for plant growth and development. Overexpression of pumpkin GA 7-oxidase (CmGA7ox) in Arabidopsis (Arabidopsis thaliana) resulted in seedlings with elongated roots, taller plants that flower earlier with only a little increase in bioactive GA4 levels compared to control plants. In the same way, overexpression of the pumpkin GA 3-oxidase1 (CmGA3ox1) resulted in a GA overdose phenotype with increased levels of endogenous GA4. This indicates that, in Arabidopsis, 7-oxidation and 3-oxidation are rate-limiting steps in GA plant hormone biosynthesis that control plant development. With an opposite effect, overexpression of pumpkin seed-specific GA 20-oxidase1 (CmGA20ox1) in Arabidopsis resulted in dwarfed plants that flower late with reduced levels of GA4 and increased levels of physiological inactive GA17 and GA25 and unexpected GA34 levels. Severe dwarfed plants were obtained by overexpression of the pumpkin GA 2-oxidase1 (CmGA2ox1) in Arabidopsis. This dramatic change in phenotype was accompanied by a considerable decrease in the levels of bioactive GA4 and an increase in the corresponding inactivation product GA34 in comparison to control plants. In this study, we demonstrate the potential of four pumpkin GA oxidase-encoding genes to modulate the GA plant hormone pool and alter plant stature and development.