优良单株家系辣木叶的表型性状分析

为挖掘辣木(Moranga oleifera)优良种质资源,对30个优良单株家系的叶片表型性状进行研究。结果表明,除叶形外,辣木不同家系间的叶柄和叶片颜色、复叶数、复叶柄长度和直径、复叶间距、叶长、叶宽均存在不同程度的差异。复叶数与复叶柄长度和直径、复叶间距、叶长、叶宽呈极显著正相关;主成分分析表明,叶长、叶宽、复叶柄长度和直径、复叶间距、叶柄和叶片颜色是区分辣木不同家系最主要的叶片性状指标。聚类分析结果表明,30个辣木家系可分为3大类,叶片表型性状存在显著差异的家系的遗传距离较远。因此,叶柄和叶片颜色、复叶数、复叶柄长度和直径、复叶间距、叶长、叶宽将为直观区分辣木家系提供参考。     

Harmful algal bloom forecast system for SW Ireland. Part II: Are operational oceanographic models useful in a HAB warning system

This study investigated the application of a three-dimensional physical hydrodynamic model in a harmful algal bloom forecast system for Bantry Bay, southwest Ireland. Modelled oceanographic conditions were studied and used to help understand observed changes in the chemical and biological patterns from the national biotoxins and phytoplankton monitoring program. The study focused on two toxic events in 2013. An upwelling event was predicted by the model prior to the appearance and population increase of potentially toxic diatoms, Pseudo-nitzschia, and associated domoic acid in shellfish. A downwelling episode was provided as a forecast in the model prior to the arrival of a Dinophysis bloom and detection of its associated biotoxins in Bay shellfish. The modelled forecast products developed included expected surface, mid-depth and bottom current pathways at the mouth of the Bay and on the adjacent shelf. The rate and direction of water volume flow at the mouth and mid-bay sections were produced by the model to examine predicted upwelling and downwelling pulses. The model also calculated the evolution of water properties (temperature, salinity and density) with depth along the Bay axis and on the adjacent continental shelf. Direct measurements of water properties at a fixed point, mid-bay, were comparable to model calculations. The operational model for southwest Ireland produces a reliable 3-day physical hydrodynamic forecast of the dominant regional physical processes that result in water exchange events between Bantry Bay and its adjacent shelf. While simulated physical hydrodynamics were provided as a 3-day forecast, the upwelling and downwelling signals from the model, closely linked to toxic HAB episodes, were evident up to 10 days prior to the contamination of shellfish in the Bay.     

The db mutation improves memory in younger mice in a model of Alzheimer's disease

Alzheimer's disease (AD) is the most common age-related neurodegenerative disease, while obesity is a major global public health problem associated with the metabolic disorder type 2 diabetes mellitus (T2DM). Chronic obesity and T2DM have been identified as invariant risk factors for dementia and late-onset AD, while their impacts on the occurrence and development of AD remain unclear. As shown in our previous study, the diabetic mutation (db, Lepr^db/db) induces mixed or vascular dementia in mature to middle-aged APP^ΔNL/ΔNL x PS1^P264L/P264L knock-in mice (db/AD). In the present study, the impacts of the db mutation on young AD mice at 10 weeks of age were evaluated. The db mutation not only conferred young AD mice with severe obesity, impaired glucose regulation and activated mammalian target of rapamycin (mTOR) signaling pathway in the mouse cortex, but lead to a surprising improvement in memory. At this young age, mice also had decreased cerebral Aβ content, which we have not observed at older ages. This was unlikely to be related to altered Aβ synthesis, as both β- and γ-secretase were unchanged. The db mutation also reduced the cortical IL-1β mRNA level and IBA1 protein level in young AD mice, with no significant effect on the activation of microglia and astrocytes. We conclude that the db mutation could transitorily improve the memory of young AD mice, a finding that may be partially explained by the relatively improved glucose homeostasis in the brains of db/AD mice compared to their counterpart AD mice, suggesting that glucose regulation could be a strategy for prevention and treatment of neurodegenerative diseases like AD.     

Genetic differentiation of Pseudoregma bambucicola population based on mtDNA COII gene

mtDNA COII gene sequences were identified and analyzed using different types of software, namely, MEGA5.0, DNAMAN, and DnaSP5.0 in four Chinese provinces, namely, Sichuan, Zhejiang, Guizhou and Shanghai. Analysis of molecular genetic variation and its genetic structure and differentiation, combined with NJ tree, MP tree analysis and analysis of molecular variance (AMOVA), at Fst = 0.0582 conclude that the genetic differentiation is low, gene flow is Nm = 8.0911, and gene exchange is sufficient. However, for the geographic populations of Pseudoregma bambucicola in the four provinces, their gene exchange is relatively weak at Nm = 0.8284, whereas the genetic differentiation is high at Fst = 0.3764. Based on the data, total nucleotide diversity between the populations is 0.00158 ± 0.00021. The results showed that the total population of Tajima’s D and Fu’s Fs results are D = ?0.885 and Fs = 0.226, respectively. The experimental numerical results showed that this total population is not significant (P > 0.10), indicating that nine different geographic populations are short-term. No expansion occurred in the internal population. This study provided a theoretical and practical basis for the comprehensive prevention and control of P. bambucicola.     

Activity of the prothoracic gland and its sensitivity to prothoracicotropic hormone in the penultimate and last-larval instar of Bombyx mori

The time course of secretion of ecdysone in vitro by the prothoracic glands of Bombyx mori was studied through the penultimate and last-larval instars. Ecdysone was produced by the glands in high amounts by the penultimate instar at 72 and 84 h while the glands in the last instar exhibited a high activity over 4 days around the time of gut purge and thereafter. The glands in the penultimate instar produced ecdysone at a low level throughout the instar before the sharp peak of activity, when they became inactive and remained so for the first 3 days of the last instar after when they regained secretory activity. Sensitivity of the glands to prothoracicotropic hormone varied in accord with the changes in their secretory activity. Inactive glands were not stimulated by 22K-prothoracicotropic hormone. In addition, glands with maximal activity in the penultimate instar were insensitive to 22K-prothoracicotropic hormone. These results suggest that the prothoracic glands in the penultimate and last-instar larvae are physiologically different.     

Protein-protein interactions between two-component system transmitter and receiver domains of Myxococcus xanthus

We present a novel dataset assessing the specificity of protein-protein interactions between 69 transmitter and receiver domains from two-component system (TCS)-signalling pathways. TCS require a conserved protein-protein interaction between partner transmitter and receiver domains for signal transduction. The complex prokaryote Myxococcus xanthus possesses an unusually large number of TCS genes, many of which have no obvious interaction partners. Interactions between TCS domains of M. xanthus were assessed using a yeast two-hybrid assay, in which domains were expressed as both bait and prey translational fusions. LacZ production was monitored as an indicator of protein-protein interaction, and the strength of interactions classified as weak, medium or strong. Two-hundred and fifty-five transmitter-receiver domain interactions were observed (46 strong), allowing identification of potential signalling partners for individual M. xanthus TCS proteins. In addition, the dataset provides interesting 'meta' information. For instance, many strong interactions were identified between different transmitter domain pairs (34) and receiver domain pairs (23), suggesting a surprisingly large degree of heterodimerisation of these domains. Proteins in our dataset that exhibited similar 'profiles' of interactions, often shared a similar biological function, suggesting that interaction profiles can provide information on biological function, even considering sets of homologous domains.     

Autism-Misregulated eIF4G Microexons Control Synaptic Translation and Higher Order Cognitive Functions

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生物信息学的研究现状及其发展问题的探讨

结合生物信息学产生的历史条件,对生物信息学的定义进行了介绍;归纳总结了现代生物信息表述、采集、储存、传递、检索的表现形式-生物学数据库的分类与分布;着重介绍了生物信息学的主要研究内容和基本的分析方法,阐明了生物信息的分析和解读模式;强调了生物信息学与其他相关学科的相关性,提出了生物信息学发展的一些亟待解决的问题及其相应的解决方案。     

聚类分析在制订育种方案中的应用

提出了品种选育中通过聚类分析划分品系的新思想。对全部目标性状做聚类分析,同类者放入同一品系中选育较好,不同类者可放入同一品系或不同品系。通过聚类分析可清楚地看出目标性状间的关系,为制订育种方案提供客观、清晰的理论依据。     

Elemental and biochemical composition of<Emphasis Type="Italic"> Nephrops norvegicus</Emphasis> (Linnaeus 1758) larvae from the Mediterranean and Irish Seas

The Norway lobster, Nephrops norvegicus, is a commercially exploited decapod which is widely distributed throughout the north-eastern Atlantic and the Mediterranean Sea. Ovigerous females originating from the Mediterranean and the Irish Seas were held in the laboratory until larvae hatched. Biomass and biochemical composition, as well as digestive gland structure, were examined in newly hatched larvae from these two regions. In addition, previously published data from a North Sea population were included in our comparison. Elemental analyses showed that the absolute quantities of dry mass (DM), carbon (C), nitrogen (N) and hydrogen (H) (collectively referred to as CHN) per individual, and the C:N mass ratios, were significantly lower, while the relative CHN, protein and lipid values (in % of DM) were higher in samples from the Irish Sea compared to larvae originating from either the Mediterranean or the North Sea. As in CHN, the absolute level of protein per individual was higher in larvae from the Mediterranean, while no significant differences were observed in the individual lipid contents. Likewise, the digestive gland structure at hatching did not show any differences between study areas. Intraspecific variability in biomass and chemical composition of newly hatched larvae from different regions may be related to differential patterns of reproduction in regions with different climatic conditions. Lobster larvae hatch in the Mediterranean Sea predominantly in winter when both water temperature and planktonic food availability are at a minimum, while hatching in the Irish Sea occurs under more favourable conditions in spring. Hence, significantly higher wet mass, dry mass and protein values in Mediterranean larvae may represent adaptive traits allowing for early posthatching survival and development under food-limited conditions in an oligotrophic environment.Communicated by H.-D. Franke