Global crop improvement networks to bridge technology gaps

To ensure future food security, there is an urgent need for improved co-ordination of agricultural research. While advances in biotechnology hold considerable promise, significant technology gaps exist that may reduce their impact. Examples include an incomplete knowledge of target breeding environments, a limited understanding and/or application of optimal crop management practices, and underfunded extension services. A better co-ordinated and more globalized approach to agricultural research through the implementation of Global Crop Improvement Networks (GCIN) is proposed. Such networks could underpin agricultural research and development by providing the following types of services: (i) increased resolution and precision of environmental information, including meteorological data, soil characteristics, hydrological data, and the identification of environmental 'hotspots' for a range of biotic, abiotic, and socio-economic constraints; (ii) augmented research capacity, including network-based variety and crop management trials, faster and more comprehensive diagnosis of emerging constraints, timely sharing of new technologies, opportunities to focus research efforts better by linking groups with similar productivity constraints and complementary skills, and greater control of experimental variables in field-based phenotyping; and (iii) increased communication and impacts via more effective dissemination of new ideas and products, the integration of information globally to elicit well-timed local responses to productivity threats, an increased profile, and the publicity of threats to food security. Such outputs would help target the translation of research from the laboratory into the field while bringing the constraints of rural communities closer to the scientific community. The GCIN could provide a lens which academia, science councils, and development agencies could use to focus in on themes of common interest, and working platforms to integrate novel research approaches on crop adaptation and rural development.     

Effects of different elicitors on yield of tropane alkaloids in hairy roots of Anisodus acutangulus

The four tropane alkaloids have played a pivotal role in controlling diseases such as the toxic and septic shock, the organophosphorus poison and the acute lung injury. Here, the elicitation effect of different elicitors on the production of tropane alkaloids and the molecular mechanism of enzyme genes in the pathway was firstly demonstrated in hairy roots of Anisodus acutangulus. The results showed ethanol, methyl jasmonate and Ag⁺ could improve the accumulation of tropane alkaloids up to 1.51, 1.13 and 1.08 times after 24 h treatment, respectively (P < 0.05), whereas salicylic acid decreased the average content of tropane alkaloids. Furthermore, expression profile analysis results revealed that up-regulation of hyoscyamine-6b-hydroxylase (AaH6H) and little regulation of tropinone reducase II (AaTR2) elicited by ethanol, increased expression of putrescine N-methyltransferase I (AaPMT1) elicited by Ag⁺, elevated expression of tropinone reducase I (AaTR1) elicited by methyl jasmonate, respectively, resulted in tropane alkaloids improvement. Our results showed that hairy root culture of A. acutangulus in combination with elicitors was a promising way for production of tropane alkaloids in the future.     

Two different binding modes of α-synuclein to lipid vesicles depending on its aggregation state

Aggregation of α-synuclein is involved in the pathogenesis of Parkinson's disease (PD). Studies of in vitro aggregation of α-synuclein are rendered complex because of the formation of a heterogeneous population of oligomers. With the use of confocal single-molecule fluorescence techniques, we demonstrate that small aggregates (oligomers) of α-synuclein formed from unbound monomeric species in the presence of organic solvent (DMSO) and iron (Fe³⁺) ions have a high affinity to bind to model membranes, regardless of the lipid-composition or membrane curvature. This binding mode contrasts with the well-established membrane binding of α-synuclein monomers, which is accompanied with α-helix formation and requires membranes with high curvature, defects in the lipid packing, and/or negatively charged lipids. Additionally, we demonstrate that membrane-bound α-synuclein monomers are protected from aggregation. Finally, we identified compounds that potently dissolved vesicle-bound α-synuclein oligomers into monomers, leaving the lipid vesicles intact. As it is commonly believed that formation of oligomers is related PD progression, such compounds may provide a promising strategy for the design of novel therapeutic drugs in Parkinson's disease.     

Oxidized low-density lipoprotein induces secretion of interleukin-1β by macrophages via reactive oxygen species-dependent NLRP3 inflammasome activation

Oxidized low-density lipoprotein (ox-LDL) is a critical mediator of atherogenesis. Macrophage uptake of ox-LDL and their subsequent development into foam cells is the principal event in atherosclerosis. Interleukin-1β (IL-1β), a prototypic multifunctional cytokine involved in inflammation, has an important effect on the pathogenesis and progression of atherosclerosis. Here we show that the phagocytosis of ox-LDL can induce human macrophages to secrete IL-1β by activating the NLRP3 inflammasome, and we further show that the activation of the NLRP3 inflammasome is dependent on the generation of reactive oxygen species and is related to the cathepsin B pathway. Furthermore, ox-LDL can upregulate the expression of the pro-IL-1β protein, thus priming IL-1β secretion. Therefore, our results suggest that the role of ox-LDL in atherosclerosis-related inflammation may involve the activation of the NLRP3 inflammasome.     

Polydatin protects learning and memory impairments in a rat model of vascular dementia

Polydatin is one of the most common encountered stilbenes of nature and a key component of the Chinese herb Polygonum cuspidatum. This study is to investigate the effects of polydatin on learning and memory impairments induced by chronic cerebral hypoperfusion in rats, as well as the potential mechanism. Both common carotid arteries and both vertebral arteries occlusion (four-vessel occlusion, 4-VO) induced severe cognitive deficits tested by water maze task, along with oxidative stress in hippocampus. Oral administration of polydatin for 30 days markedly attenuated cognitive deficits compared with the control (p < 0.05). Biochemical determination revealed that polydatin decreased the production of malondialdehyde (MDA) and significantly increased the activities of superoxide dismutase (SOD) and catalase (CAT). Additionally, polydatin effectively alleviated the injuries of cultured neurons induced by oxygen-glucose deprivation (OGD). These results suggest that polydatin exhibit therapeutic potential for vascular dementia, which is most likely related, at least in part, to its anti-oxidant activity and the direct protection of neurons.     

Covariation in plant functional traits and soil fertility within two species-rich forests

The distribution of plant species along environmental gradients is expected to be predictable based on organismal function. Plant functional trait research has shown that trait values generally vary predictably along broad-scale climatic and soil gradients. This work has also demonstrated that at any one point along these gradients there is a large amount of interspecific trait variation. The present research proposes that this variation may be explained by the local-scale sorting of traits along soil fertility and acidity axes. Specifically, we predicted that trait values associated with high resource acquisition and growth rates would be found on soils that are more fertile and less acidic. We tested the expected relationships at the species-level and quadrat-level (20 × 20 m) using two large forest plots in Panama and China that contain over 450 species combined. Predicted relationships between leaf area and wood density and soil fertility were supported in some instances, but the majority of the predicted relationships were rejected. Alternative resource axes, such as light gradients, therefore likely play a larger role in determining the interspecific variability in plant functional traits in the two forests studied.