Evidence that NO/cGMP/PKG signalling cascade mediates endothelium dependent inhibition of IP3R mediated Ca2+ oscillations in myocytes and pericytes of ureteric microvascular network in situ

In ureteric microvessels the antagonistic relationship between Ca²⁺ signalling in endothelium and Ca²⁺ oscillations in myocytes and pericytes of arterioles and venules involves nitric oxide (NO), but the underlying mechanisms are not well understood. In the present study we investigated the effects of carbachol and NO donor SNAP on Ca²⁺ signalling and vasomotor responses of arterioles and venules in intact urteric microvascular network in situ using confocal microscopy. Vasomotor responses of arterioles and venules induced by AVP correlated with the occurrence of Ca²⁺ oscillations in the myocytes and pericytes and were not abolished by the removal of Ca²⁺ from extracellular fluid. Carbachol-induced rise of intracellular Ca²⁺ in endothelium was accompanied by the termination of the Ca²⁺ oscillations in myocytes and pericytes. This carbachol-induced inhibitory effect on Ca²⁺ oscillations in myocytes and pericytes was reversed by ODQ, an inhibitor of soluble guanylyl cyclase (sGC) and by Rp-8-pCPT-cGMPS, an inhibitor of protein kinase G (PKG). Ca²⁺ oscillations in myocytes and pericytes were also effectively blocked by NO donor SNAP. An Inhibitory effect of SNAP was markedly enhanced by zaprinast, a selective inhibitor of cGMP-specific phosphodiesterase-5, and reversed by sGC inhibitor, ODQ and PKG inhibitor, Rp-8-pCPT-cGMPS. The cGMP analogue and selective PKG activator 8pCPT-cGMP also induced inhibition of the AVP-induced Ca²⁺ oscillations in myocytes and pericytes. SNAP had no effects on Ca²⁺ oscillations induced by caffeine in distributing arcade arterioles. Consequently, we conclude that NO- mediated inhibition of Ca²⁺ oscillations in myocytes and pericytes predominantly recruits the cGMP/PKG dependent pathway. The inhibitory effect of NO/cGMP/PKG cascade is associated with suppressed Ca²⁺ release from the SR of myocytes and pericytes selectively via the inositol triphosphate receptor (IP₃R) channels.     

Niche partitioning due to adaptive foraging reverses effects of nestedness and connectance on pollination network stability

Much research debates whether properties of ecological networks such as nestedness and connectance stabilise biological communities while ignoring key behavioural aspects of organisms within these networks. Here, we computationally assess how adaptive foraging (AF) behaviour interacts with network architecture to determine the stability of plant–pollinator networks. We find that AF reverses negative effects of nestedness and positive effects of connectance on the stability of the networks by partitioning the niches among species within guilds. This behaviour enables generalist pollinators to preferentially forage on the most specialised of their plant partners which increases the pollination services to specialist plants and cedes the resources of generalist plants to specialist pollinators. We corroborate these behavioural preferences with intensive field observations of bee foraging. Our results show that incorporating key organismal behaviours with well‐known biological mechanisms such as consumer‐resource interactions into the analysis of ecological networks may greatly improve our understanding of complex ecosystems.     

Social carry‐over effects underpin trans‐seasonally linked structure in a wild bird population

Spatial structure underpins numerous population processes by determining the environment individuals' experience and which other individuals they encounter. Yet, how the social landscape influences individuals' spatial decisions remains largely unexplored. Wild great tits (Parus major) form freely moving winter flocks, but choose a single location to establish a breeding territory over the spring. We demonstrate that individuals' winter social associations carry‐over into their subsequent spatial decisions, as individuals breed nearer to those they were most associated with during winter. Further, they also form territory boundaries with their closest winter associates, irrespective of breeding distance. These findings were consistent across years, and among all demographic classes, suggesting that such social carry‐over effects may be general. Thus, prior social structure can shape the spatial proximity, and fine‐scale arrangement, of breeding individuals. In this way, social networks can influence a wide range of processes linked to individuals' breeding locations, including other social interactions themselves.     

An ectomycorrhizal nitrogen economy facilitates monodominance in a neotropical forest

Tropical forests are renowned for their high diversity, yet in many sites a single tree species accounts for the majority of the individuals in a stand. An explanation for these monodominant forests remains elusive, but may be linked to mycorrhizal symbioses. We tested three hypotheses by which ectomycorrhizas might facilitate the dominance of the tree, Oreomunnea mexicana, in montane tropical forest in Panama. We tested whether access to ectomycorrhizal networks improved growth and survival of seedlings, evaluated whether ectomycorrhizal fungi promote seedling growth via positive plant–soil feedback, and measured whether Oreomunnea reduced inorganic nitrogen availability. We found no evidence that Oreomunnea benefits from ectomycorrhizal networks or plant–soil feedback. However, we found three‐fold higher soil nitrate and ammonium concentrations outside than inside Oreomunnea‐dominated forest and a correlation between soil nitrate and Oreomunnea abundance in plots. Ectomycorrhizal effects on nitrogen cycling might therefore provide an explanation for the monodominance of ectomycorrhizal tree species worldwide.     

Assessment of artificial substrates for evaluating groundwater microbial quality

Protection of groundwater resources requires the development of reliable ecological indicators. Microorganisms involved in ecological services or being associated with particular hosts or habitats could be used for this purpose. Nevertheless, their tracking remains limited because of sampling issues, and a lack of devices for their long term monitoring. In the present study, three artificial substrates (glass and clay beads, and gravel particles) were tested in terms of efficacy at favoring bacterial growth, and at capturing bacterial diversity of waters (i.e., groundwater, surface water and wastewater). Total proteins, total carbohydrates, dehydrogenase and hydrolytic activities were used to monitor biofilm development on these artificial substrates. Fingerprinting analyses based on rrs (16S rRNA) − rrl (23S rRNA) spacer analyses (ARISA) and next generation sequencing (NGS) of partial rrs DNA segments (V5-V6) were used to compare operating taxonomic units (OTUs), and infer bacterial genera trapped on these substrates. Glass beads were found less efficient than the other two artificial substrates at increasing protein contents and microbial activities (hydrolytic and dehydrogenase activities). ARISA showed a discrimination of bacterial communities developing on artificial substrates that was matching water types. An incubation period of 7 days allowed a reliable assessment of bacterial diversity. From this incubation period, around 75% of water genera with more than four V5-V6 rrs DNA sequences detected in a water type were recovered from biofilms growing on artificial substrates. Based on relative abundances of genera, clay beads and gravel particles were more efficient than glass beads to capture and obtain bacterial communities matching those of the initial waters. Between 45–67% of similarities were found for these artificial substrates while it was between 36 and 43% for glass beads. This study demonstrated clay beads and gravel particles as being efficient tools for capturing bacterial diversity and monitoring bacterial growth. Overall, clay beads appeared the best choice for field monitoring because of the ease of their size standardization in comparison with gravel particles.     

基于深度最大输出网络的抗体种型特异性B细胞表位预测

B细胞表位研究有助于肽段疫苗研制,抗体研制以及疾病诊断和治疗研究.不同的B细胞表位诱导免疫系统产生不同的抗体种型,探索研究能够诱导特异性抗体产生的B细胞表位具有重要意义.基于二肽组成特征,利用深度最大输出网络算法训练构建三个二类分类器,分别对应诱导三种不同特异性抗体的B细胞表位,即IgA表位,IgE表位以及IgG表位.通过五折交叉验证训练和测试这三个分类器,获得AUC的值分别为0.78,0.93以及0.78.IgA表位和IgE表位分类器的预测能力优于其它IgA表位和IgE表位分类器,IgG表位分类器和其它IgG表位分类器的预测能力相当.     

Differential Expression of microRNAs and their Regulatory Networks in Skin Tissue of Liaoning Cashmere Goat during Hair Follicle Cycles

MicroRNAs (miRNAs) are endogenous small noncoding RNA molecules that negatively regulate gene expression. Herein, we investigated a selective number of miRNAs for their expression in skin tissue of Liaoning Cashmere goat during hair follicle cycles, and their intracellular regulatory networks were constructed based on bioinformatics analysis. The relative expression of six miRNAs (mir-103-3p, -15b-5p, 17-5p, -200b, -25-3p, and -30c-5p) at anagen phase is significantly higher than that at catagen and/or telogen phases. In comparison to anagen, the relative expression of seven miRNAs (mir-148a-3p, -199a-3p, -199a-5p, -24-3p, -30a-5p, -30e-5p, and -29a-3p) was revealed to be significantly up-regulated at catagen and/or telogen stages. The network analyses of miRNAs indicated those miRNAs investigated might be directly or indirectly involved in several signaling pathways through their target genes. These results provided a foundation for further insight into the roles of these miRNAs in skin tissue of Liaoning Cashmere goat during hair follicle cycles.     

Plasma Proteome Signature of Sepsis: a Functionally Connected Protein Network

Sepsis is an extreme host response to infection that leads to loss of organ function and cardiovascular integrity. Mortality from sepsis is on the rise. Despite more than three decades of research and clinical trials, specific diagnostic and therapeutic strategies for sepsis are still absent. The use of LFQ‐ and TMT‐based quantitative proteomics is reported here to study the plasma proteome in five mouse models of sepsis. A knowledge‐based interpretation of the data reveals a protein network with extensive connectivity through documented functional or physical interactions. The individual proteins in the network all have a documented role in sepsis and are known to be extracellular. The changes in protein abundance observed in the mouse models of sepsis have for the most part the same directionality (increased or decreased abundance) as reported in the literature for human sepsis. This network has been named the Plasma Proteome Signature of Sepsis (PPSS). The PPSS is a quantifiable molecular readout that can supplant the current symptom‐based approach used to diagnose sepsis. This type of molecular interpretation of sepsis, its progression, and its response to therapeutic intervention are an important step in advancing our understanding of sepsis, and for discovering and evaluating new therapeutic strategies.     

Comparative Nuclear Proteomics Analysis Provides Insight into the Mechanism of Signaling and Immune Response to Blast Disease Caused by Magnaporthe oryzae in Rice

Modulation of plant immune system by extrinsic/intrinsic factors and host‐specific determinants fine‐tunes cellular components involving multiple organelles, particularly nucleus to mount resistance against pathogen attack. Rice blast, caused by hemibiotrophic fungus Magnaporthe oryzae, is one of the most devastating diseases that adversely affect rice productivity. However, the role of nuclear proteins and their regulation in response to M. oryzae remains unknown. Here, the nucleus‐associated immune pathways in blast‐resistant rice genotype are elucidated. Temporal analysis of nuclear proteome is carried out using 2‐DE coupled MS/MS analysis. A total of 140 immune responsive proteins are identified associated with nuclear reorganization, cell division, energy production/deprivation, signaling, and gene regulation. The proteome data are interrogated using correlation network analysis that identified significant functional modules pointing toward immune‐related coinciding processes through a common mechanism of remodeling and homeostasis. Novel clues regarding blast resistance include nucleus‐associated redox homeostasis and glycolytic enzyme–mediated chromatin organization which manipulates cell division and immunity. Taken together, the study herein provides evidence that the coordination of nuclear function and reprogramming of host translational machinery regulate resistance mechanism against blast disease.