Over‐expression of bacterial γ‐glutamylcysteine synthetase (GSH1) in plastids affects photosynthesis,growth and sulphur metabolism in poplar (Populus tremula × Populus alba) dependent on the resulting γ‐glutamylcysteine and glutathione levels

We compared three transgenic poplar lines over‐expressing the bacterial γ‐glutamylcysteine synthetase (GSH1) targeted to plastids. Lines Lggs6 and Lggs12 have two copies, while line Lggs20 has three copies of the transgene. The three lines differ in their expression levels of the transgene and in the accumulation of γ‐glutamylcysteine (γ‐EC) and glutathione (GSH) in leaves, roots and phloem exudates. The lowest transgene expression level was observed in line Lggs6 which showed an increased growth, an enhanced rate of photosynthesis and a decreased excitation pressure (1‐qP). The latter typically represents a lower reduction state of the plastoquinone pool, and thereby facilitates electron flow along the electron transport chain. Line Lggs12 showed the highest transgene expression level, highest γ‐EC accumulation in leaves and highest GSH enrichment in phloem exudates and roots. This line also exhibited a reduced growth, and after a prolonged growth of 4.5 months, symptoms of leaf injury. Decreased maximum quantum yield (F_v/F_m) indicated down‐regulation of photosystem II reaction centre (PSII RC), which correlates with decreased PSII RC protein D1 (PsbA) and diminished light‐harvesting complex (Lhcb1). Potential effects of changes in chloroplastic and cytosolic GSH contents on photosynthesis, growth and the whole‐plant sulphur nutrition are discussed for each line.     

Eugenol specialty chemical production in transgenic poplar (Populus tremula × P. alba) field trials

A foundational study assessed effects of biochemical pathway introduction into poplar to produce eugenol, chavicol, p‐anol, isoeugenol and their sequestered storage products, from potentially available substrates, coniferyl and p‐coumaryl alcohols. At the onset, it was unknown whether significant carbon flux to monolignols vs. other phenylpropanoid (acetate) pathway metabolites would be kinetically favoured. Various transgenic poplar lines generated eugenol and chavicol glucosides in ca. 0.45% (~0.35 and ~0.1%, respectively) of dry weight foliage tissue in field trials, as well as their corresponding aglycones in trace amounts. There were only traces of any of these metabolites in branch tissues, even after ~4‐year field trials. Levels of bioproduct accumulation in foliage plateaued, even at the lowest introduced gene expression levels, suggesting limited monolignol substrate availability. Nevertheless, this level still allows foliage collection for platform chemical production, with the remaining (stem) biomass available for wood, pulp/paper and bioenergy product purposes. Several transformed lines displayed unexpected precocious flowering after 4‐year field trial growth. This necessitated terminating (felling) these particular plants, as USDA APHIS prohibits the possibility of their interacting (cross‐pollination, etc.) with wild‐type (native plant) lines. In future, additional biotechnological approaches can be employed (e.g. gene editing) to produce sterile plant lines, to avoid such complications. While increased gene expression did not increase target bioproduct accumulation, the exciting possibility now exists of significantly increasing their amounts (e.g. 10‐ to 40‐fold plus) in foliage and stems via systematic deployment of numerous ‘omics’, systems biology, synthetic biology and metabolic flux modelling approaches.     

Effect of larval brain extracts derived from three swallowtail butterflies,Papilio helenus L., P. machaon L. and P. memnon L., on seasonal morph development of P. xuthus L. (Lepidoptera: Papilionidae)

Adults of the three papilionid butterflies, Papilio helenus L., Papilio machaon L. and Papilio memnon L., exhibit seasonal diphenism comprising spring and summer morphs. To elucidate the physiological mechanism underlying seasonal morph development in papilionid butterflies, we investigated whether a cerebral factor showing summer‐morph‐producing hormone (SMPH) activity is present in the brain of three Papilio species using an assay system with chilled male short‐day pupae of P. xuthus L. When 2% NaCl extracts derived from 20 larval brains of the three species were injected into abdomens of chilled male short‐day pupae of P. xuthus, all recipients destined to develop into spring‐morph adults developed into summer‐ and intermediate‐morph adults. On the other hand, all recipients injected with distilled water as a control developed into spring‐morph adults. These results indicate that a cerebral factor showing SMPH activity is present in the larval brain of the three Papilio species. Additionally, all recipients injected with 2% NaCl extracts derived from 20 adult brains of Bombyx mori L. also developed into summer‐ and intermediate‐morph adults. The results revealed that SMPH or a cerebral factor showing SMPH activity is widely distributed among lepidopteran insects.     

向小黑杨转化蜘蛛杀虫毒素基因（英文）

近年来,危害小黑杨Populus simonii×Ｐ.nigra的害虫发生严重,给林业生产造成很大损失。为了提高小黑杨的抗虫能力,避免使用杀虫剂带来的污染,用农杆菌介导法将澳大利亚漏斗蛛Atrax robustus的毒蛋白基因和苏云金芽孢杆菌CryⅠA（b）基因C末端的融合基因BGT转化入小黑杨。PCR 和Southern印记分析转基因植株,结果表明,BGT杀虫基因已经整合在小黑杨基因组上。活性实验表明,取食转基因杨树6天和9天后,舞毒蛾Lymantria dispar 2龄幼虫的校正死亡率分别是37.0%和92.6%。方差分析表明取食转基因和对照杨树的舞毒蛾幼虫体重差异显著。这些结果显示转基因杨树上的舞毒蛾的发育速率受到影响。     

Low genetic and morphological differentiation in the European species complex of Rosa sherardii,R. mollis and R. villosa (Rosa section Caninae subsection Vestitae)

The polyploid species complex of Rosa villosa sensu lato (Rosa section Caninae subsection Vestitae) consists of three morphologically similar polyploid species: R. sherardii, R. mollis and R. villosa. Whereas R. sherardii is distributed in central Europe, R. mollis and R. villosa represent a vicariant species pair occurring in northern Europe and in mountains of central and eastern Europe, respectively. In this study we analysed multiple data sets (morphology, cytology, microsatellites, AFLP and plastid DNA sequences) to re‐evaluate the systematics of these species and to examine whether cytological differences are reflected in the taxonomy and geographical distributions. Furthermore, these data sets were used to evaluate hypotheses explaining the vicariant distribution of R. mollis and R. villosa. None of these data sets revealed a clear‐cut differentiation between the species. Cytological and molecular data argued for a discrete taxonomic position of the predominantly pentaploid R. sherardii, but these data did not support a separation between the mostly tetraploid R. mollis and R. villosa. Population genetics revealed that samples of the latter species were assembled according to ploidy, but not to species affiliation or geographical distribution. Thus, we assume that the cytologically polymorphic original species had a continuous range prior to the last glaciation period and survived on nunataks or in non‐glaciated coastal regions in northern Europe, but that it failed to recover its former range after the retreat of the ice sheets. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 240–256.     

The novel ruthenium—γ‐linolenic complex [Ru2(aGLA)4Cl] inhibits C6 rat glioma cell proliferation and induces changes in mitochondrial membrane potential,increased reactive oxygen species generation and apoptosis in vitro

The present study reports the synthesis of a novel compound with the formula [Ru₂(aGLA)4Cl] according to elemental analyses data, referred to as Ru₂GLA. The electronic spectra of Ru₂GLA is typical of a mixed valent diruthenium(II,III) carboxylate. Ru₂GLA was synthesized with the aim of combining and possibly improving the anti‐tumour properties of the two active components ruthenium and γ‐linolenic acid (GLA). The properties of Ru₂GLA were tested in C6 rat glioma cells by analysing cell number, viability, lipid droplet formation, apoptosis, cell cycle distribution, mitochondrial membrane potential and reactive oxygen species. Ru₂GLA inhibited cell proliferation in a time and concentration dependent manner. Nile Red staining suggested that Ru₂GLA enters the cells and ICP‐AES elemental analysis found an increase in ruthenium from <0.02 to 425 mg/Kg in treated cells. The sub‐G1 apoptotic cell population was increased by Ru₂GLA (22 ± 5.2%) when analysed by FACS and this was confirmed by Hoechst staining of nuclei. Mitochondrial membrane potential was decreased in the presence of Ru₂GLA (44 ± 2.3%). In contrast, the cells which maintained a high mitochondrial membrane potential had an increase (18 ± 1.5%) in reactive oxygen species generation. Both decreased mitochondrial membrane potential and increased reactive oxygen species generation may be involved in triggering apoptosis in Ru₂GLA exposed cells. The EC₅₀ for Ru₂GLA decreased with increasing time of exposure from 285 µM at 24 h, 211 µM at 48 h to 81 µM at 72 h. In conclusion, Ru₂GLA is a novel drug with antiproliferative properties in C6 glioma cells and is a potential candidate for novel therapies in gliomas. Copyright © 2009 John Wiley & Sons, Ltd.     

Acute metal stress in Populus tremula×P. alba (717‐1B4 genotype): Leaf and cambial proteome changes induced by cadmium2+

The comprehension of metal homeostasis in plants requires the identification of molecular markers linked to stress tolerance. Proteomic changes in leaves and cambial zone of Populus tremula×P. alba (717‐1B4 genotype) were analyzed after 61 days of exposure to cadmium (Cd) 360 mg/kg soil dry weight in pot‐soil cultures. The treatment led to an acute Cd stress with a reduction of growth and photosynthesis. Cd stress induced changes in the display of 120 spots for leaf tissue and 153 spots for the cambial zone. It involved a reduced photosynthesis, resulting in a profound reorganisation of carbon and carbohydrate metabolisms in both tissues. Cambial cells underwent stress from the Cd actually present inside the tissue but also a deprivation of photosynthates caused by leaf stress. An important tissue specificity of the response was observed, according to the differences in cell structures and functions.     

Geographic variation of color polymorphism in two sibling ladybird species,Harmonia yedoensis and H. axyridis (Coleoptera: Coccinellidae)

Geographical variation of elytra color pattern in two sibling ladybird species, Harmonia yedoensis and H. axyridis (Coleoptera: Coccinellidae), was examined. The two species are distributed sympatrically in central Japan; however, only H. yedoensis and H. axyridis occur in the Ryukyu Islands (southern Japan) and Hokkaido island (northern Japan), respectively. The frequency of elytra color patterns was significantly different between the two species in all sympatric locations and our results were inconsistent with the classical theory on Müllerian mimicry. The most dominant pattern of H. axyridis was the least dominant of H. yedoensis in all sympatric populations. Furthermore, the frequency of the non‐melanic form (red ground color with or without black spots) increased towards the south in H. yedoensis. This tendency was in contrast to the known geographical cline in H. axyridis in which the melanic form (black ground color with red spots) was gradually displaced with the non‐melanic form northwards in the Japanese archipelago. We discuss possible selective factors including predator avoidance, thermal adaptation and reproductive character displacement, all of which might contribute to the maintenance of the color polymorphism in the two Harmonia species.     

Reactions of the haloalcohols HO(CH2)nCl (n = 2, 3) with platinum(II) - alkynyl and -alkyne complexes. X-ray crystal structure of trans-[Pt(Me) {C(OCH2CH2Cl) (CH2Ph)} (PPh3)2] [BF4]

The chloro complexes trans-[Pt(Me)(Cl)(PPh₃)₂], after treatment with AgBF₄, react with 1-alkynes HC---C---R in the presence of NEt₃ to afford the corresponding acetylide derivatives trans-[Pt(Me) (C---C---R) (PPh₃)₂] (R = p-tolyl (1), Ph (2), C(CH₃)₃ (3)). These complexes, with the exception of the t-butylacetylide complex, react with the chloroalcohols HO(CH₂)_nCl (n = 2, 3) in the presence of 1 equiv. of HBF₄ to afford the alkyl(chloroalkoxy)carbene complexes trans-[Pt(Me) {C[O(CH₂)_nCl](CH₂R) } (PPh₃)₂][BF₄] (R = p-tolyl, N = 2 (4), N = 3 (5); R=Ph, N = 2 (6)). A similar reaction of the bis(acetylide) complex trans-[Pt(C---C---Ph)₂(PMe₂Ph)₂] with 2 equiv. HBF₄ and 3-chloro-1-propanol affords trans-[Pt(C---CPh) {C(OCH₂CH₂CH₂Cl)(CH₂Ph) } (PMe₂Ph)₂][BF₄] (7). T alkyl(chloroalkoxy)-carbene complex trans-[Pt(Me) {C(OCH₂CH₂Cl)(CH₂Ph) } (PPh₃)₂][BF₄] (8) is formed by reaction of trans-[Pt(Me)(Cl)(PPh₃)₂], after treatment with AgBF₄ in HOCH₂CH₂Cl, with phenylacetylene in the presence of 1 equiv. of n-BuLi. The reaction of the dimer [Pt(Cl)(μ-Cl)(PMe₂Ph)]₂ with p-tolylacetylene and 3-chloro-1-propanol yields cis-[PtCl₂{C(OCH₂CH₂CH₂Cl)(CH₂C₆H₄-p-Me}(PMe₂Ph)] (9). The X-ray molecular structure of (8) has been determined. It crystallizes in the orthorhombic system, space group Pna2₁, with a = 11.785(2), B = 29.418(4), C = 15.409(3) Å, V = 4889(1) ų and Z = 4. The carbene ligand is perpendicular to the Pt(II) coordination plane; the PtC(carbene) bond distance is 2.01(1) Å and the short C(carbene)-O bond distance of 1.30(1) Å suggests extensive electronic delocalization within the Pt---C(carbene)---O moietry.