The coordination of public and private goods production is essential for bacterial adaptation to environmental changes. Quorum sensing (QS) regulates this balance by mediating the trade-off between the communal benefits of "public goods," such as siderophores and antibiotics, and the individual metabolic needs fulfilled by "private goods," such as intracellular metabolites utilized for growth and survival. Pseudomonas fluorescens 2P24 harbors a LasI/LasR-type QS system, MupI/MupR, which regulates mupirocin production through signaling molecules. This study explores how QS coordinates carbon and nitrogen metabolism to optimize the production of key secondary metabolites, including 2,4-diacetylphloroglucinol (2,4-DAPG), mupirocin, and siderophores, which serve as public goods. Loss of QS disrupts this balance by enhancing the Krebs cycle, denitrification, pyruvate anaplerosis, and ammonium assimilation, lead to halted 2,4-DAPG and mupirocin synthesis and increased siderophore production. In the absence of QS, elevated siderophore production compensates for iron acquisition, ensuring rapid cellular growth. Under nutrient-limited or high cell density conditions, MupR regulates carbon and nitrogen fluxes to sustain public goods production. These findings highlight QS as a key environmental sensor that fine-tunes resource allocation, bacterial fitness, and adaptation to ecological and nutritional conditions, suggesting the potential for QS-targeted approaches to enhance antibiotic production and agricultural sustainability.

Signaling between rhizosphere microorganisms is crucial in bacteria interaction and communication, shaping the rhizomicrobiome. Plant growth-promoting bacterium Pseudomonas produces a spectrum of important antibiotics to inhibit plant pathogens, albeit with an associated metabolic burden. Antibiotics could function as intra- and interspecies signals at subinhibitory concentrations to coordinate gene expression and microbial behaviors. In this work, we characterized pyoluteorin as an interspecies signal that modulates the biosynthesis of 2,4-diacetylphloroglucinol (2,4-DAPG), a broad-spectrum biocontrol agent, in non-pyoluteorin-producing Pseudomonas fluorescens 2P24. We demonstrated that the key transcriptional repressor PhlF from the 2,4-DAPG biosynthetic gene cluster spontaneously senses pyoluteorin, enhancing repression of the phlA promoter activity and inhibiting 2,4-DAPG synthesis in P. fluorescens 2P24. Pyoluteorin also binds to another transcriptional repressor, PhlH, from the 2,4-DAPG biosynthetic gene cluster, subsequently releasing the transcription of phlG, which facilitates the hydrolysis of 2,4-DAPG. Both PhlF and PhlH are simultaneously involved in sensing exogenous pyoluteorin to regulate the 2,4-DAPG biosynthetic operon, playing a crucial role in controlling antibiotic metabolites in response to environmental changes. Further phylogenetic and structural analyses demonstrated that PhlH and PhlF are widely distributed across Pseudomonas spp. with conserved ligand-binding domains. The findings shed new light on the regulatory mechanism of 2,4-DAPG biosynthesis underlying interspecies signaling by pyoluteorin and provide invaluable clues for the rational design of co-inhabiting Pseudomonas spp. as biocontrol agents. IMPORTANCE:Rhizosphere microorganisms release vital signals that shape microbial communities, with antibiotics at low concentrations acting as intra- and interspecies signals. However, the mechanisms of these signals in coordinating gene expression are unclear. In non-pyoluteorin-producing Pseudomonas fluorescens 2P24, pyoluteorin was identified as an interspecies signal that regulates the phl biosynthesis gene cluster for 2,4-DAPG production. TetR family repressors PhlH and PhlF were found to positively regulate 2,4-DAPG hydrolysis and negatively regulate its synthesis in response to pyoluteorin. Structural modeling and docking analyses revealed the interactions between pyoluteorin and both PhlH and PhlF, modulating gene expression. Phylogenetic analyses showed a wide distribution of PhlH and PhlF across Pseudomonas spp. with conserved ligand-binding domains. These findings deepen our understanding of interspecies signaling mechanisms and highlight the potential for designing co-inhabiting Pseudomonas spp. as effective biocontrol agents.

The regulation of circadian rhythms and the sleep–wake states involves in multiple neural circuits. The suprachiasmatic nucleus (SCN) is a circadian pacemaker that controls the rhythmic oscillation of mammalian behaviors. The basal forebrain (BF) is a critical brain region of sleep–wake regulation, which is the downstream of the SCN. Retrograde tracing of cholera toxin subunit B showed a direct projection from the SCN to the horizontal limbs of diagonal band (HDB), a subregion of the BF. However, the underlying function of the SCN–HDB pathway remains poorly understood. Herein, activation of this pathway significantly increased non–rapid eye movement (NREM) sleep during the dark phase by using optogenetic recordings. Moreover, activation of this pathway significantly induced NREM sleep during the dark phase for first 4 h by using chemogenetic methods. Taken together, these findings reveal that the SCN–HDB pathway participates in NREM sleep regulation and provides direct evidence of a novel SCN-related pathway involved in sleep–wake states regulation.

The unique sedative activities with rapid arousal of dexmedetomidine (Dex) are not fully understood. Growing evidence suggests the involvement of the ventrolateral preoptic area (VLPO) in sleep-wake cycle. The major type in the VLPO is sleep-active neurons, inhibited by noradrenaline (NA(-) neurons). The other type of neurons is activated by NA (NA(+) neurons), which are wake-active. Previous research showed that Dex-induced sedation and sleep homeostasis likely share common mechanisms. To explore the underlying mechanisms of Dex in the VLPO, in vivo polysomnography recording and in vitro electrophysiological recording were used in our study. Bath application of Dex (2 & mu;M) increased the firing rate of both VLPO NA(-) and NA(+) neurons. Compared to the control group, there was no difference in the firing rate of both VLPO NA(-) and NA(+) neurons after Dex (2 & mu;M) and RS79948 (1 mM) administration, an & alpha;(2) receptor antagonist. No difference was detected regarding resting membrane potential (RMP) amplitude of both VLPO NA (-) and NA(+) neurons after application of Dex (2 & mu;M). Moreover, Dex (2 & mu;M) significantly reduced the frequency of miniature inhibitory postsynaptic currents (mIPSCs) in both VLPO NA(-) and NA(+) neurons. These electrophysiology results were consistent with behavioral sedation, with increased nonrapid eye movement sleep (NREM sleep) and increased expression of c-Fos in the VLPO during the dark phase after intraperitoneal injection with Dex (80 & mu;g/kg). In conclusion, Dex activates NA(-) and NA(+) neurons in the VLPO via presynaptic & alpha;(2) receptors. This mechanism may explain the unique sedative properties with rapid arousal.Summary StatementDexmedetomidine is an important ICU sedative. The mechanism of dexmedetomidine is not fully understood. Activating NA(-) and NA(+) neurons in the VLPO by dexmedetomidine using polysomnography and electrophysiological recording, this may explain the unique sedative properties with rapid arousal.

The production of secondary metabolites is a major mechanism used by beneficial rhizobacteria to antagonize plant pathogens. These bacteria have evolved to coordinate the production of different secondary metabolites due to the heavy metabolic burden imposed by secondary metabolism. However, for most secondary metabolites produced by bacteria, it is not known how their biosynthesis is coordinated. Here, we showed that PhlH from the rhizobacterium Pseudomonas fluorescens is a TetR-family regulator coordinating the expression of enzymes related to the biosynthesis of several secondary metabolites, including 2,4-diacetylphloroglucinol (2,4-DAPG), mupirocin, and pyoverdine. We present structures of PhlH in both its apo form and 2,4-DAPG-bound form and elucidate its ligand-recognizing and allosteric switching mechanisms. Moreover, we found that dissociation of 2,4-DAPG from the ligand-binding domain of PhlH was sufficient to allosterically trigger a pendulum-like movement of the DNA-binding domains within the PhlH dimer, leading to a closed-to-open conformational transition. Finally, molecular dynamics simulations confirmed that two distinct conformational states were stabilized by specific hydrogen bonding interactions and that disruption of these hydrogen bonds had profound effects on the conformational transition. Our findings not only reveal a well-conserved route of allosteric signal transduction in TetR-family regulators but also provide novel mechanistic insights into bacterial metabolic coregulation.

Background Ubiquitination is essential for many cellular processes in eukaryotes, including 26S proteasome-dependent protein degradation, cell cycle progression, transcriptional regulation, and signal transduction. Although numerous ubiquitinated proteins have been empirically identified, their cognate ubiquitin E3 ligases remain largely unknown. Results Here, we generate a complete ubiquitin E3 ligase-encoding open reading frames (UbE3-ORFeome) library containing 98.94% of the 1515 E3 ligase genes in the rice ( Oryza sativa L . ) genome. In the test screens with four known ubiquitinated proteins, we identify both known and new E3s. The interaction and degradation between several E3s and their substrates are confirmed in vitro and in vivo. In addition, we identify the F-box E3 ligase OsFBK16 as a hub-interacting protein of the phenylalanine ammonia lyase family OsPAL1–OsPAL7. We demonstrate that OsFBK16 promotes the degradation of OsPAL1, OsPAL5, and OsPAL6. Remarkably, we find that overexpression of OsPAL1 or OsPAL6 as well as loss-of-function of OsFBK16 in rice displayed enhanced blast resistance, indicating that OsFBK16 degrades OsPALs to negatively regulate rice immunity. Conclusions The rice UbE3-ORFeome is the first complete E3 ligase library in plants and represents a powerful proteomic resource for rapid identification of the cognate E3 ligases of ubiquitinated proteins and establishment of functional E3–substrate interactome in plants.

Wheat is one of the most important staple crops worldwide. Fusarium head blight severely reduces wheat yield and quality. Cultivation of a novel type of cleistogamous wheat mutant, ZK001, which was created by static magnetic field treatment, is a new strategy for controlling Fusarium head blight. However, little is known about the mechanism of cleistogamy in wheat. The present study demonstrated that anthers of ZK001 were retained on the glumes at all flowering stages, whereas those of YM18 were extruded from the paleae and lemmae. There was a clear difference in the morphological characteristics of lodicules between YM18 and ZK001. Lodicule calcium and potassium contents were significantly higher in YM18 than in ZK001 from white to yellow anther stages. In Fusarium head blight resistance, the diseased kernel rate and deoxynivalenol content of ZK001 were markedly lower than those of YM18 and QM725. Comparative transcriptome analysis of YM18 and ZK001 was performed to identify regulatory mechanisms of cleistogamy. The main differentially expressed genes identified in the spikelets of YM18 and ZK001 at the green anther stage were associated with cell walls, carbohydrates, phytohormones, water channel, and ion binding, transport, and homeostasis. These differentially expressed genes may play an important role in regulating cellular homeostasis, osmotic pressure, and lodicule development. The results indicate that ZK001 lost the ability to push the lemmae and paleae apart during the flowering stage because of the thin lodicules. ZK001 was speculated to provide structural barriers for Fusarium head blight during the flowering stage. The thin lodicule of ZK001 results from low levels of soluble sugar, calcium ions, and potassium ions in the lodicules. These levels are regulated by differentially expressed genes.

The fragile X mental retardation protein (FMRP) is a regulator of local translation through its mRNA targets in the neurons. Previous studies have demonstrated that FMRP may function in distinct ways during the development of different visual subcircuits. However, the localization of the FMRP in different types of retinal cells is unclear. In this work, the FMRP expression in rat retina was detected by Western blot and immunofluorescence double labeling. Results showed that the FMRP expression could be detected in rat retina and that the FMRP had a strong immunoreaction (IR) in the ganglion cell (GC) layer, inner nucleus layer (INL), and outer plexiform layer (OPL) of rat retina. In the outer retina, the bipolar cells (BCs) labeled by homeobox protein ChX10 (ChX10) and the horizontal cells (HCs) labeled by calbindin (CB) were FMRP-positive. In the inner retina, GABAergic amacrine cells (ACs) labeled by glutamate decarbonylase colocalized with the FMRP. The dopaminergic ACs (tyrosine hydroxylase marker) and cholinergic ACs (choline acetyltransferase (ChAT) marker) were co-labeled with the FMRP. In most GCs (labeled by Brn3a) and melanopsin-positive intrinsically photosensitive retinal GCs (ipRGCs) were also FMRP-positive. The FMRP expression was observed in the cellular retinal binding protein-positive Müller cells. These results suggest that the FMRP could be involved in the visual pathway transmission.

Background Wheat is one of the most important staple crops worldwide. Fusarium head blight (FHB) severely affects wheat yield and quality. A novel bread wheat mutant, ZK001, characterized as cleistogamic was isolated from a non-cleistogamous variety Yumai 18 (YM18) through static magnetic field mutagenesis. Cleistogamy is a promising strategy for controlling FHB. However, little is known about the mechanism of cleistogamy in wheat. Methods We performed a FHB resistance test to identify the FHB infection rate of ZK001. We also measured the agronomic traits of ZK001 and the starch and total soluble sugar contents of lodicules in YM18 and ZK001. Finally, we performed comparative studies at the proteome level between YM18 and ZK001 based on the proteomic technique of isobaric tags for relative and absolute quantification. Results The infection rate of ZK001 was lower than that of its wild-type and Aikang 58. The abnormal lodicules of ZK001 lost the ability to push the lemma and palea apart during the flowering stage. Proteome analysis showed that the main differentially abundant proteins (DAPs) were related to carbohydrate metabolism, protein transport, and calcium ion binding. These DAPs may work together to regulate cellular homeostasis, osmotic pressure and the development of lodicules. This hypothesis is supported by the analysis of starch, soluble sugar content in the lodicules as well as the results of Quantitative reverse transcription polymerase chain reaction. Conclusions Proteomic analysis has provided comprehensive information that should be useful for further research on the lodicule development mechanism in wheat. The ZK001 mutant is optimal for studying flower development in wheat and could be very important for FHB resistant projects via conventional crossing.

Background: Wheat is one of the most important staple crops worldwide.Fusarium head blight severely affects wheat yield and quality.A novel bread wheat mutant, ZK001, characterised as cleistogamic was isolated from a non-cleistogamous variety (YM18) through static magnetic field mutagenesis.Cleistogamy is a promising strategy for controlling Fusarium head blight.However, little is known about the mechanism of cleistogamy in wheat.Methods: We performed a Fusarium head blight resistance test to identify the Fusarium head blight infection rate of ZK001.We also measured the agronomic traits of ZK001 and the starch and total soluble sugar contents of lodicules in YM18 and ZK001.Finally, we performed comparative studies at the proteome level between YM18 and ZK001 based on the proteomic technique of isobaric tags for relative and absolute quantification.Results: The infection rate of ZK001 was lower than that of its wild type and AK58.The abnormal lodicules of ZK001 lost the ability to push the lemma and palea apart during the flowering stage.Proteome analysis showed that the main differentially abundant proteins were related to carbohydrate metabolism, protein transport, and calcium ion binding.These differentially abundant proteins may work together to regulate cellular homeostasis, osmotic pressure and the development of lodicules.This hypothesis is supported by the analysis of starch, soluble sugar content in the lodicules as well as the results of qRT-PCR.Conclusions: Proteomic analysis has provided comprehensive information that should be useful for further research on the lodicule development mechanism in wheat.The ZK001 mutant is optimal for studying flower development in wheat and could be very important for Fusarium head blight resistant projects via conventional crossing.

Coptotermes suzhouensis (Isoptera: Rhinotermitidae) is a significant subterranean termite pest of wooden structures and is widely distributed in southeastern China. The complete mitochondrial DNA sequence of C. suzhouensis was analyzed in this study. The mitogenome was a circular molecule of 15,764 bp in length, which contained 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an A+T-rich region with a gene arrangement typical of Isoptera mitogenomes. All PCGs were initiated by ATN codons and terminated by complete termination codons (TAA), except COX2, ND5, and Cytb, which ended with an incomplete termination codon T. All tRNAs displayed a typical clover-leaf structure, except for tRNASer(AGN), which did not contain the stem-loop structure in the DHU arm. The A+T content (69.23%) of the A+T-rich region (949 bp) was higher than that of the entire mitogenome (65.60%), and two different sets of repeat units (A+B) were distributed in this region. Comparison of complete mitogenome sequences with those of Coptotermes formosanus indicated that the two taxa have very high genetic similarity. Forty-one representative termite species were used to construct phylogenetic trees by maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analyses also strongly supported (BPP, MLBP, and MPBP = 100%) that all C. suzhouensis and C. formosanus samples gathered into one clade with genetic distances between 0.000 and 0.002. This study provides molecular evidence for a more robust phylogenetic position of C. suzhouensis and inferrs that C. suzhouensis was the synonymy of C. formosanus.

Danzhi Jiangtang Capsule (DJC), a traditional Chinese medicinal formula, has been used clinically in treating diabetes and diabetic nephropathy (DN). We previously demonstrated that DJC is capable of improving renal function in patients and rats with DN, but the mechanisms underlying these therapeutic benefits of DJC are not quite clear yet. In this study, STZ-induced diabetic rats were orally administered DJC for 8 weeks. Fasting blood glucose, renal function indicators in the serum, renal index, and the expression of proteins related to JAK-STAT signaling pathway were evaluated at the end of the experiment. The kidneys were sliced for pathological histology. Antioxidant status was assessed by measuring SOD, LPO and MDA in serum. The expression levels of COX2, iNOS, SOCS and the phosphorylation status of JAK2, STAT1, and STAT3 in renal tissues were evaluated by Western blot analyses. IL-6, TNF-α, and MCP-1 expression levels in renal tissues were determined using double-antibody sandwich ELISA. Diabetic renal dysfunction and its associated pathologies were ameliorated by DJC treatment. DJC significantly reversed the high expression of COX2 and iNOS in renal tissues. Furthermore, DJC inhibited the JAK2-STAT1/STAT3-SOCS3 signaling pathway, resulting in decreased concentrations of IL-6, TNF-α, and MCP-1. Moreover, the oxidant status in the kidney was substantially ameliorated by DJC treatment. In conclusion, the ability of DJC to ameliorate diabetic renal dysfunction and the associated pathologies of this disease might be due to its antioxidant capacity and suppression of the JAK2-STAT1/STAT3 cascade.

To solve the problem of conventional INS not applicable to polar regions,a mechanization of inertial navigation system based on transverse terrestrial coordinate was presented.According to this mechanization,error model of inertial navigation system based on transverse terrestrial coordinate was established.Taking a certain type of naval vessel as an example,the applicability of the system for polar regions was studied by simulation analysis of system performance under the static base and dynamic base.In the simulation analysis of dynamic base,a route across the north pole was planned for the ship which simulated the complex motion state of the ship.The simulation results show that inertial navigation system based on transverse terrestrial coordinate overcomes the shortcoming of conventional INS not suitable for polar regions,and it can also provide high precision false attitude and location information for polar navigation ships.

The antidiabetic properties and anti-inflammatory effects of Danzhi Jiangtang Capsules (DJC) have been demonstrated in clinical and laboratory experiments. In this study, we explored whether DJC can ameliorate advanced glycation end products- (AGEs-) mediated cell injury and the precise mechanisms of DJC in treating diabetic nephropathy (DN). Western blot analysis was employed to assess the expressions of iNOS, COX2, and SOCS and the phosphorylation of JAK2, STAT1, and STAT3 in glomerular mesangial cells (GMCs) after treatment with DJC. TNF- α , IL-6, and MCP-1 were determined using double-antibody sandwich ELISA. ROS and NADPH oxidase activity were measured by DCFH-DA assay and lucigenin-enhanced chemiluminescence, respectively. DJC significantly reversed the AGEs-induced expression of COX2 and iNOS. Moreover, DJC inhibited the AGEs-induced JAK2-STAT1/STAT3 activation, resulting in the inhibition of inflammatory cytokines such as IL-6, MCP-1, and TNF- α in a concentration-dependent manner. The ability of DJC to suppress STAT activation was also verified by the observation that DJC significantly increased the SOCS3 protein level. DJC reversed the AGEs-induced accumulation of ROS and NADPH oxidase activity, thus confirming that DJC possesses antioxidant activity. The results suggest that the anti-inflammatory effects of DJC in GMCs may be due to its ability to suppress the JAK2-STAT1/STAT3 cascades and reduce ROS production.

Polar regions are located at high latitudes. There may be several choices for chart projection of polar regions, including Mercator projection, polar stereographic projection, gnomonic projection, Lambert con-formal projection and transverse Mercator projection. The Mercator projection introduces an increasingly large deformation near the polar regions and deformation of infinity at the poles on the chart. With polar stereographic projection, the rhumb line is not straight on the chart. Gnomonic projection is not conformal projection, therefore, it is very difficult to measure range and bearing directly on the chart. On a Lambert conformal chart, longitude is represented by angle. With the transverse Mercator projection, almost all lines of latitude and longitude are curved. Hence, none of the aforementioned projection is particularly suitable for safe polar navigation and reliable chart work. To solve the above problems, a false graticules is con-structed and the problem of transforming between false and true latitude and longitude is solved. A transverse Mercator chart based on this false graticules is drawn using Matlab. The characteristics of this new type of chart are similar to those of a Mercator chart and there is still deformation distortion in the polar region, but lines of false longitude and false latitude are mutually parallel and respectively orthogonal. Overall, this new type of chart would be convenient for doing polar chart work.

The complete nucleotide sequence of the mitochondrial genome of Reticulitermes labralis was analyzed. This mitochondrial genome is a circular molecule of 15,914 bp in length and has the same gene content and organization as that found in other Reticulitermes species. It contains 13 protein-coding genes (PCGs), 22 tRNAs, two rRNAs (12S and 16S rRNA) and a non-coding AT-rich region (CR). The total base composition is strongly biased toward A-T nucleotides (65.1%). Most of the genes are encoded on the H strand, except for the other four protein-coding genes and eight tRNA genes on the L strand. The phylogenetic tree based on the nucleotide sequences of 13 mitochondrial PCGs using the Bayesian inference method supports the traditional morphologically analysis.

利用同源克隆技术分离了安徽省40个不同地理种群白蚁样品的线粒体CO Ⅱ基因,并进行了序列分析,结合GenBank中的数据,构建系统进化树并进行了遗传变异分析.序列比对分析表明,40个白蚁样品分属3个属(土白蚁属、散白蚁属、乳白蚁属)的6个种,3个属COⅡ全长基因中多态性位点分别占0.1％、9.2％和7.4％;基因序列中A+T含量为61.8％,显著高于C+G含量,碱基变异的主要形式为转换.同种白蚁个体间的碱基差异明显小于不同种间的差异,种内个体间的差异为0.1％～1.3％,种间个体间的差异为5.5％～7.6％.分子系统树表明,乳白蚁属和散白蚁属构成姐妹关系聚成一支,亲缘关系较近,而土白蚁属关系较远,分子鉴定及系统进化分析的结果与传统形态学结果相一致,是对形态分类的有力支持.

酵母甘露聚糖（Mannan,简称Man）是能参与生物信息流影响生物体、特别是在糖基化方面起着重要调控作用的生物信息大分子。它是否能在抑制生物机体中肿瘤生长方面具有重要作用?研究结果表明:酵母甘露聚糖既能使患S-180瘤鼠的体质增强的同时又有抑制其体内所患S-180瘤生长的功效。Man抑制患鼠机体内的S-180瘤生长的功效（抑瘤率）随用量的增加而提高,当Man用量达360 mg（40 mg/Kg/d·9d）时,其抑瘤率达98.4%的最高水平,此时鼠体重增加1.66倍。Man的抑瘤功效有最佳适用量并存在性别敏感性,通常是雄性鼠的抑瘤率高于雌性鼠。Man抑制鼠S-180肿瘤生长的作用优于市售5-氟尿嘧啶的作用。

植物微核实验是细胞遗传学实验中的一个经典项目,属于验证性实验。课程组以培养学生初步科研能力为目标,将该实验改造成学生自主设计性实验项目"利用微核技术检测环境中有毒有害物",由学生自主组成团队、查找资料、设计实验方案、实施并汇报。经过五年的实践,取得了良好的教学效果。

选择藻华现象严重的巢湖作为采样点,取3个不同位置的水样通过0.22 μm的纤维滤膜过滤,培养后加入适应期的藻液中,取黄化藻液作为分离菌种的材料,初筛菌株经反复试验获得有较强抑藻能力的菌株,经生理生化鉴定及16S rDNA分子鉴定其种属.初筛得到45个菌株,有两个菌株WD1和WD2表现出溶藻作用.两株细菌的菌液经离心、高温灭菌、细胞破碎等处理对供试藻鱼腥藻也均有不同程度的抑制作用.分离得到两株溶藻细菌,WD1为约氏不动杆菌,WD2为门多萨假单胞菌.