Genetic variation and drought response in two Populus × euramericana genotypes through 2-DE proteomic analysis of leaves from field and glasshouse cultivated plants

Genotype and water deficit effects on leaf 2-DE protein profiles of two Populus deltoides × Populus nigra, cv. ‘Agathe_F’ and ‘Cima’, were analysed over a short-term period of 18 days in glasshouse using 4-month-old rooted cuttings and over a long-lasting period of 86 days in open field using 4-year-old rooted cuttings. Leaf proteomes were analyzed using two-dimensional gel electrophoresis, and proteins were identified after database searching from MS peptide spectra.A reliable genotype effect was observed in the leaf proteome over experiment locations, water regimes and sampling dates. Quantitative differences between genotypes were found. Most of them corresponded to proteins matching isoforms or post-translational modification variants. However, ‘Cima’ displayed the highest abundance of antioxidant enzymes.In response to water deficit, about 10% of the reproducible spots significantly varied regardless of the experiment location, among which about 25% also displayed genotype-dependent variations. As a whole, while ‘Cima’ differed from ‘Agathe_F’ by increased abundance of enzymes involved in photorespiration and in oxidative stress, ‘Agathe_F’ was mainly differentiated by increased abundance of enzymes involved in photosynthesis.     

对生化分离技术实验的探讨

实验教学的改进和提高,是教学改革的重要一环。阐述了作者在教学实践的过程中,对生化分离技术实验中的原料选取、处理方法、仪器设备等方面所作的改进尝试而取得的成效。     

Herbivore intake/habitat productivity correlations can help ascertain re-introduction potential for the Barbary macaque

Re-introductions are increasingly used conservation tools. Often, criteria for re-introducing species are based on policies or politics and little attention paid, albeit theoretical, to understanding what ecological possibilities habitats may have in sustaining introduced animals. Assessing potential carrying capacities is complex but easier for grazers, since biomass of these herbivores is empirically correlated with habitat primary productivity.The case is made here that the Barbary macaque, Macaca sylvanus, a vulnerable North African primate with a large surplus captive stock, can be viewed as a grazer. Because of this attribute, and unlike congenerics, it is possible to estimate potential densities in extant habitats in a fashion similar to predicting stocking levels for domestic herbivores. Thus, from values of consumable primary productivity for domestic stock in Mediterranean countries and the monkey's energy requirements, attainable macaque populations in studied habitats could be much higher than actual. Though these numbers may be unreachable in nature, this study shows that present macaque populations could increase after restorative management of habitats in which re-stocking with captive-born animals may play a part. However, since only 10% of potential monkey habitat in Morocco and Algeria is occupied by the species, finding areas for releasing captive-born macaques is more advisable.     

Stomach capacity as a directing factor in prey size selection of three-spined stickleback

Three-spined stickleback consumed prey of one size until the stomach was full whereafter similar-sized prey were rejected, but smaller prey were consumed. This evidence leads to the prediction of a shift in prey size preference as a result of the constraint imposed by remaining stomach capacity.     

《酶工程》教学与课程建设的探讨

酶工程是生物技术专业的主干课程,其主要内容是研究酶的生产和应用。为了使酶工程的教学适合时代发展的需要,培养合格的从事酶工程研究及生产的技术人才,以多年酶工程教学实践为基础,集中介绍该门课程教学与建设的体会及其思考。     

以达托霉素产生菌菌株改造为主线的微生物工程综合实验的探索和实践

为使本科学生更好地掌握微生物工程的基本实验操作技能和前沿研究技术,探索将教师的科研成果转化为教学实验,构建了以达托霉素产生菌菌株改造为主线的微生物工程综合实验。在教学模式、实验内容设计、教学安排和考核方式等方面进行实践,取得了较好的教学效果,培养了本科学生的科研技能、科研思维和研究素质。     

Host plant preference based on salicylate chemistry in a willow leaf beetle (Chrysomela aeneicollis)

Summary Chrysomela aeneicollis (Coleoptera: Chrysomelidae) uses salicin from its host plant (Salix spp.) to produce a defensive secretion, salicylaldehyde. Because it requires salicin for this secretion, I predicted that C. aeneicollis should be attracted to willows which possess salicin and other salicylates. To test this prediction, I determined the host-plant preferences of C. aeneicollis among four potential hosts which occur in the Sierra Nevada range of eastern California. These species have very different salicylate chemistries but do not differ in nutritional quality for C. aeneicollis. In oviposition-preference tests, gravid females showed no preference between a salicylate-poor species, S. lutea, and a salicylate-rich species, S. orestera. However in feeding-choice tests, both larvae and adults preferred S. orestera over S. lutea. This preference was not affected by the species on which the larvae were reared. In other feeding tests, adults preferred S. orestera over two medium-salicylate species, S. boothi and S. geyeriana, regardless of which host species they had been feeding on in nature. In a final feeding test, adults were stimulated to feed by salicin itself. In nature, the relative abundances of C. aeneicollis adults and egg clutches among these species correspond to the adult feeding preference in the laboratory. Additionally, multiple regression analyses showed that adult abundance was not related to among-clone differences in leaf toughness or nutritional quality, but rather to salicin content and plant size. Thus for C. aeneicollis, both laboratory and field results demonstrate a preference for salicylate-rich willows which is partly responsible for the increased level of attack on them.     

下丘脑Nesfatin-1/NUCB2对糖尿病小鼠摄食的影响

目的:探讨下丘脑神经肽NUCB2与Tsumura Suzuki(TS)多基因突变2型糖尿病(T2DM)小鼠摄食过多的关系。方法:将动物分为Tsumura Suzuki糖尿病(TSD)小鼠、正常小鼠;监视器监测小鼠摄食量;分析血生化指标;定量RT-PCR分析摄食相关神经肽m RNA表达水平;放射免疫分析法检测nesfatin-1蛋白水平。结果:与年龄匹配的TSN小鼠相比,TSD小鼠在1月龄就存在体重增加(P<0.05)和高瘦素血症(P<0.05),3-12月龄出现贪食(P<0.05)、高血糖(P<0.05)、高血脂(P<0.05)和高胰岛素血症(P<0.05),且3-12月龄时厌食肽nesfatin-1前体核连蛋白2(NUCB2)m RNA和nesfatin-1蛋白水平均显著降低(P<0.05~0.01);TSD小鼠下丘脑甘丙肽、黑色素浓集素、神经肽Y及前黑素细胞皮质素原m RNA水平也有显著改变(P<0.05)。结论:下丘脑NUCB2介导信号通路破坏可能导致TSD小鼠摄食过多。     

荔枝蝽取食行为的研究

在越冬前和产卵期,荔枝蝽Tessaratoma papillosa Drury在寄主植物-荔枝树的花枝、嫩枝和老枝上都有取食行为。但在这两个不同时期, 其取食行为有显著差异。在越冬前,只有50%～70%的成虫在各类枝条上取食;而处于产卵期的荔枝蝽成虫,在各类枝条上,100%积极取食,且其取食前时间显著短于越冬前在同类枝条上的取食前时间。同一时期在不同枝叶上,荔枝蝽的取食行为也有显著差异。被置于嫩枝叶和花枝上的成虫取食前时间明显短于被置于老枝叶上者;在有选择的情况下,两个时期的成虫都明显地选择在花枝和嫩枝上取食。经分析测定：在不同生长时期,荔枝树的花枝和嫩枝的含水量与含氮量均较老枝叶中的高,可溶性糖含量的变化较大;组织结构也存在明显差异。     

Examining the link between dietary specialization and foraging modes of stream‐dwelling brown trout Salmo trutta

The aim of this study was to explore differences in dietary specialization across two foraging modes (benthic v. surface‐drift foraging) of stream‐dwelling brown trout Salmo trutta. The degree of inter‐individual niche variation within each foraging mode was high, but the dietary specialization was maintained between foraging modes. This study supports the view that if aquatic invertebrates are more abundant and accessible than surface prey, the individuals will not specialize on surface prey (surface‐drift foraging).