温带气旋对一代粘虫迁飞的影响:2015年个例分析

【目的】一代粘虫Mythimna separate(Walker)蛾大多在5月中旬至6月中旬集群外迁,而此时我国温带气旋活动较为频繁,由气旋活动引起的风场条件的变化会对一代粘虫的迁入区分布造成极大影响,因此阐明温带气旋对一代粘虫迁飞过程的影响是预测2代粘虫发生的重要前提。【方法】通过在江苏姜堰、安徽金安和山东宁津设立高空灯监测点,获取三地粘虫空中种群过境动态,结合WRF(Weather Research and Forecast)模式输出的精细风温场资料分析2015年温带气旋对一代粘虫迁飞的影响。【结果】2015年5月东亚反气旋频繁过境,一代粘虫在反气旋影响下多往西南和西北方向迁飞。6月上旬在东北低涡和蒙古气旋的影响下,一代粘虫可迁入东北地区为害。【结论】春夏之交频发的温带气旋是导致我国二代粘虫大范围为害的重要原因。     

植物细胞生物反应器培养的研究进展(I)

利用植物细胞大规模悬浮培养生产植物有用代谢产物在近些年来取得了很大发展,但植物细胞悬浮培养的工业化应用受到来自生物及工程技术上的限制.本文针对植物细胞培养的基本特点,详细讨论了与大规模生产有关的工程技术方面的问题,如植物细胞聚集、溶氧及气体成分、流体性能、剪切力对植物细胞培养产生的影响.     

PTPRN2 and PLCβ1 promote metastatic breast cancer cell migration through PI(4,5)P2‐dependent actin remodeling

Altered abundance of phosphatidyl inositides (PIs) is a feature of cancer. Various PIs mark the identity of diverse membranes in normal and malignant cells. Phosphatidylinositol 4,5‐bisphosphate (PI(4,5)P₂) resides predominantly in the plasma membrane, where it regulates cellular processes by recruiting, activating, or inhibiting proteins at the plasma membrane. We find that PTPRN2 and PLCβ1 enzymatically reduce plasma membrane PI(4,5)P₂ levels in metastatic breast cancer cells through two independent mechanisms. These genes are upregulated in highly metastatic breast cancer cells, and their increased expression associates with human metastatic relapse. Reduction in plasma membrane PI(4,5)P₂ abundance by these enzymes releases the PI(4,5)P₂‐binding protein cofilin from its inactive membrane‐associated state into the cytoplasm where it mediates actin turnover dynamics, thereby enhancing cellular migration and metastatic capacity. Our findings reveal an enzymatic network that regulates metastatic cell migration through lipid‐dependent sequestration of an actin‐remodeling factor.     

Polyclonal antibodies for specific detection of tobacco host cell proteins can be efficiently generated following RuBisCO depletion and the removal of endotoxins

The production of biopharmaceutical proteins in plants requires efficient downstream processing steps that remove impurities such as host cell proteins (HCPs) and adventitious endotoxins produced by bacteria during transient expression. We therefore strived to develop effective routines for endotoxin removal from plant extracts and the subsequent use of the extracts to generate antibodies detecting a broad set of HCPs. At first, we depleted the superabundant protein ribulose‐1,5‐bisphosphate carboxylase/oxygenase (RuBisCO) for which PEG precipitation achieved the best results, preventing a dominant immune reaction against this protein. We found that a mixture of sera from rabbits immunized with pre‐depleted or post‐depleted extracts detected more HCPs than the individual sera used alone. We also developed a powerful endotoxin removal procedure using Polymyxin B for extracts from wild type plants or a combination of fiber‐flow filtration and EndoTrap Blue for tobacco plants infiltrated with Agrobacterium tumefaciens. The antibodies we generated will be useful for quality and performance assessment in future process development and the methods we present can easily be transferred to other expression systems rendering them useful in the field of plant molecular farming.     

Multidimensional biases,gaps and uncertainties in global plant occurrence information

Plants are a hyperdiverse clade that plays a key role in maintaining ecological and evolutionary processes as well as human livelihoods. Biases, gaps and uncertainties in plant occurrence information remain a central problem in ecology and conservation, but these limitations remain largely unassessed globally. In this synthesis, we propose a conceptual framework for analysing gaps in information coverage, information uncertainties and biases in these metrics along taxonomic, geographical and temporal dimensions, and apply it to all c. 370 000 species of land plants. To this end, we integrated 120 million point‐occurrence records with independent databases on plant taxonomy, distributions and conservation status. We find that different data limitations are prevalent in each dimension. Different metrics of information coverage and uncertainty are largely uncorrelated, and reducing taxonomic, spatial or temporal uncertainty by filtering out records would usually come at great costs to coverage. In light of these multidimensional data limitations, we discuss prospects for global plant ecological and biogeographical research, monitoring and conservation and outline critical next steps towards more effective information usage and mobilisation. Our study provides an empirical baseline for evaluating and improving global floristic knowledge, along with a conceptual framework that can be applied to study other hyperdiverse clades.     

Dichotomous strategies? The migration of Whimbrels breeding in the eastern Canadian sub‐Arctic

The conservation of migratory birds requires internationally coordinated efforts that, in turn, demand an understanding of population dynamics and connectivity throughout a species' range. Whimbrels (Numenius phaeopus) are a widespread long‐distance migratory shorebird with two disparate North American breeding populations. Monitoring efforts suggest that at least one of these populations is declining, but the level of migratory connectivity linking the two populations to specific non‐breeding sites or identifiable conservation threats remains unclear. We deployed light‐level geolocators in 2012 to track the migration of Whimbrels breeding near Churchill, Manitoba, Canada. In 2013, we recovered 11 of these geolocators, yielding complete migration tracks for nine individuals. During southbound migration, six of the nine Whimbrels stopped at two staging sites on the mid‐Atlantic seaboard of the United States for an average of 22 days, whereas three individuals made nonstop flights of ~8000 km from Churchill to South America. All individuals subsequently spent the entire non‐breeding season along the northern coasts of Brazil and Suriname. On their way north, all birds stopped at the same two staging sites used during southbound migration. Individuals staged at these sites for an average of 34 days, significantly longer than during southbound migration, and all departed within a 5‐day period to undertake nonstop flights ranging from 2600 to 3100 km to the breeding grounds. These extended spring stopovers suggest that female Whimbrels likely employ a mixed breeding strategy, drawing on both endogenous and exogenous reserves to produce their eggs. Our results also demonstrate that this breeding population exhibits a high degree of connectivity among breeding, staging, and wintering sites. As with other long‐distance migratory shorebirds, conservation efforts for this population of Whimbrels must therefore focus on a small, but widely spaced, suite of sites that support a large proportion of the population.     

Consequences of a mixed reproductive system in the hog peanut,Amphicarpaea bracteata, (Fabaceae)

Summary The forest annual, Amphicarpaea bracteata L. can reproduce via aerial chasmogamous, aerial cleistogamous, and subterranean cleistogamous flowers. Both plant size and light intensity influenced the utilization of the three modes of reproduction. chasmogamous and aerial cleistogamous flower number and the ratio of chasmogamous flowers to the total number of aerial flowers increased with plant size. The latter demonstrated a shift to xenogamy and outbreeding in larger plants. Light intensity indirectly influenced reproductive modes through its infuence on plant size. Seed set by both types of aerial flowers was low and unrelated to plant size. Subterranean seed number and the total dry weight of subterranean seeds per plant increased with size. The subterranean seeds of Amphicarpaea bracteata are thirty-four times larger than the aerial seeds (fresh weight). Under field conditions, subterranean seeds had greater germination after one year than acrial seeds. The plants arising from subterranean seeds were significantly larger and more fecund than those from aerial seeds. Seeds produced by aerial cleistogamous, hand selfpollinated chasmogamous, and naturally pollinated chasmogamous flowers had equivalent germination rates and produced plants of equal size and fecundity. This suggests that the outbred progeny from chasmogamous flowers have no advantage over the inbred progeny from aerial cleistogamous flowers.     

一种水稻卷叶性状的遗传分析

对水稻卷叶品种流岗卷叶粳与4个平展叶品种及1个卷叶标志基因(rl3)系的杂交或回交后代进行了考察。结果表明,流岗卷叶粳的卷叶特性以单基因不完全显性方式遗传; 该基因与rl3基因不等位,当rl3位点处于隐性纯合时两者以累加方式发生互作。这一等位基因可作标志基因使用,暂定名为Rl(t)。 Abstract:Liugangjuanyejing is a rolled leaf mutant of rice.A genetic study on the rolled-leaf character was carried out by crossing it with four flat-leaf cultivars and a genetic marker line (with a rolled-leaf allele rl3).The results showed that this character was controlled by an incomplete dominant gene which was non-allelic to rl3 locus and that there existed additive effect between the two loci when the rl3 locus was homozygous recessiveness.This new rolled-leaf allele was provisionally named as Rl(t) and could be used as a genetic marker of rice.     

Thrombospondin-4 promotes bladder cancer cell migration and invasion via MMP2 production

Bladder cancer (BC) is the second most common urological tumour in Western countries. Approximately, 80% of patients with BC will present with non-muscle invasive bladder cancer (NMIBC), whereas a quarter will have muscle invasive disease (MIBC) at the time of BC diagnosis. However, patients with NMIBC are at risk of BC recurrence or progression into MIBC, and an MIBC prognosis is determined by the presence of progression and metastasis. Matrix metalloproteinase 2 (MMP2), a type of matrix metalloproteinase (MMP), plays a major role in tumour invasion and is well-characterized in BC prognosis. In BC, the mechanisms regulating MMP2 expression, and, in turn, promote cancer invasion, have hardly been explored. Thrombospondin-4 (THBS4/TSP4) is a matricellular glycoprotein that regulates multiple biological functions, including proliferation, angiogenesis, cell adhesion and extracellular matrix modelling. Based on the results of a meta-analysis in the Gene Expression Profiling Interactive Analysis 2 database, we observed that TSP4 expression levels were consistent with overall survival (OS) rate and BC progression, with the highest expression levels observed in the advanced stages of BC and associated with poor OS rate. In our pilot experiments, incubation with recombinant TSP4 promoted the migration and invasion in BC cells. Furthermore, MMP2 expression levels increased after recombinant TSP4 incubation. TSP4-induced-MMP2 expression and cell motility were regulated via the AKT signalling pathway. Our findings facilitate further investigation into TSP4 silencing-based therapeutic strategies for BC.