两种同域分布蹄蝠在开阔度不同的环境中回声定位声波的可塑性

在广西桂林研究了同域分布的大蹄蝠(Hipposideros armiger)和中蹄蝠(H.larvatus)在不同开阔度环境中回声定位声波信号的变化。用超声波仪录制自由悬挂和分别释放于人工"大棚"和"小棚"内飞行的蝙蝠的回声定位声波,使用超声分析软件分析声脉冲时程、主频率及声脉冲间隔,通过重复测量方差分析比较不同状态下的声波参数。结果表明:中蹄蝠声波的主频在悬挂状态下最高,小棚内飞行时次之,大棚内飞行最低;两种蹄蝠声波的脉冲时程和脉冲间隔在悬挂状态下最长,大棚内飞行次之,小棚内飞行最低。总之,这两种蹄蝠的回声定位声波能够随所处状态的变化而变化,可根据生境的复杂度调节声讯号,具有明显的声波可塑性。     

中国四齿芥属一新记录种——帕米尔四齿芥

报道了十字花科(Brassicaceae)四齿芥属(Tetracme Bunge)一中国新记录种——帕米尔四齿芥(Tetracme pamirica Vassilcz.)。标本采自西藏自治区札达县底雅乡,生于干燥的河谷坡地。该种与相近种四齿芥的区别是,角果长10~13 mm,种子长1~2 mm。凭证标本保存在内蒙古大学植物标本馆(HIMC)。     

BiP Inducer X: An ER Stress Inhibitor for Enhancing Recombinant Antibody Production in CHO Cell Culture

Prolonged endoplasmic reticulum (ER) stress reduces protein synthesis and induces apoptosis in mammalian cells. When dimethyl sulfoxide (DMSO), a specific monoclonal antibody productivity (q_mAb)‐enhancing reagent, is added to recombinant Chinese hamster ovary (rCHO) cell cultures (GSR cell line), it induces ER stress and apoptosis in a dose‐dependent manner. To determine an effective ER stress inhibitor, three ER stress inhibitors (BiP inducer X [BIX], tauroursodeoxycholic acid, and carbazole) are examined and BIX shows the best production performance. Coaddition of BIX (50 μm ) with DMSO extends the culture longevity and enhances q_mAb. As a result, the maximum mAb concentration is significantly increased with improved galactosylation. Coaddition of BIX significantly increases the expression level of binding immunoglobulin protein (BiP) followed by increased expression of chaperones (calnexin and GRP94) and galactosyltransferase. Furthermore, the expression levels of CHOP, a well‐known ER stress marker, and cleaved caspase‐3 are significantly reduced, suggesting that BIX addition reduces ER stress‐induced cell death by relieving ER stress. The beneficial effect of BIX on mAb production is also demonstrated with another q_mAb‐enhancing reagent (sodium butyrate) and a different rCHO cell line (CS13‐1.00). Taken together, BIX is an effective ER stress inhibitor that can be used to increase mAb production in rCHO cells.     

Cell-Type-Specific Gene Expression Profiling in Adult Mouse Brain Reveals Normal and Disease-State Signatures

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Parabacteroides distasonis Alleviates Obesity and Metabolic Dysfunctions via Production of Succinate and Secondary Bile Acids

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Forest characteristics and population structure of Glyptostrobus pensilis,a globally endangered relict species of southeastern China

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam.     

Integrative taxonomy recognized a new cryptic species within Stipa grandis from Loess Plateau of China

Stipa shanxiensis, a cryptic species within Stipa grandis that originated from central and western China, is described based on morphological, genomic, and ecological data from field and common garden experiments. Stipa shanxiensis morphologically resembles S. grandis, although phylogenetically it is closely related to the less morphologically similar Stipa baicalensis and Stipa krylovii. Of the eight significant morphological differences between S. shanxiensis and S. grandis, the two, cauline ligules longer than 2 cm with a filiform apex, and hairs shorter than 0.2 mm on the adaxial surface of the cauline uppermost leaves can be used to distinguish the species. Results from a common garden experiment verified that the two diagnostic characteristics were relatively stable and less morphologically plastic in response to environmental variation. Furthermore, a significant ecological divergence was found between S. shanxiensis and S. grandis, such that the former preferred warmer and more humid climates, and their predicted distribution was generally separated. Taken together, our results highlight that the integrative taxonomic approach was valuable for recognizing a new cryptic species in Stipa. In particular, we find that common garden experiments involving the effects of growth stage and characteristic position helped to morphologically diagnose cryptic species. These findings may also facilitate our understandings of ecological adaption and phenotypic plasticity in response to environmental change.     

AoATG5 plays pleiotropic roles in vegetative growth,cell nucleus development,conidiation, and virulence in the nematode-trapping fungus Arthrobotrys oligospora

Science China Life Sciences - Autophagy is an evolutionarily conserved process in eukaryotes, which is regulated by autophagy-related genes (ATGs). Arthrobotrys oligospora is a representative...