Marine anoxia linked to abrupt global warming during Earth's penultimate icehouse.

Piecing together the history of carbon (C) perturbation events throughout Earth's history has provided key insights into how the Earth system responds to abrupt warming. Previous studies, however, focused on short-term warming events that were superimposed on longer-term greenhouse climate states. Here, we present an integrated proxy (C and uranium [U] isotopes and paleo CO2) and multicomponent modeling approach to investigate an abrupt C perturbation and global warming event (∼304 Ma) that occurred during a paleo-glacial state. We report pronounced negative C and U isotopic excursions coincident with a doubling of atmospheric CO2 partial pressure and a biodiversity nadir. The isotopic excursions can be linked to an injection of ∼9,000 Gt of organic matter­derived C over ∼300 kyr and to near 20% of areal extent of seafloor anoxia. Earth system modeling indicates that widespread anoxic conditions can be linked to enhanced thermocline stratification and increased nutrient fluxes during this global warming within an icehouse.

Promotion of the resistance of human oral epithelial cells to herpes simplex virus type I infection via N6-methyladenosine modification.

OBJECTIVE: This study aimed to explore the mechanism behind N6-methyladenosine (m6A) modification of the total ribonucleic acid (RNA) involved in the resistance to herpes simplex virus type I (HSV-1) infection in oral epithelial cells. METHOD: The variation in m6A modification level on messenger RNA following HSV-1 infection was determined using the RNA dot blot method. The expression levels of alpha-ketoglutarate-dependent dioxygenase lab homolog 5 (ALKBH5) protein and fatty mass and obesity-associated genes (FTO) were determined using real-time fluorescence quantification polymerase chain reaction and the western blot technique, respectively. Next, after suppressing the expression of ALKBH5 or FTO via small interfering RNA, human immortalised oral epithelial cells (HIOECs) were infected with HSV-1, followed by measurement of the viral load or expression level of type I interferon (I-IFN) and interferon-stimulated genes (ISGs). RESULTS: The m6A modification level was significantly increased following HSV-1 infection of the HIOECs (P < 0.05), while the expression of ALKBH5 and FTO genes was reduced (P < 0.01). Moreover, the suppression of ALKBH5 or FTO increased the production of I-IFN and ISGs during the HSV-1 infection of the HIOECs (P < 0.01), and the viral load was significantly reduced (P < 0.01). CONCLUSION: During oral HSV-1 infection, the m6A level was increased through the down-regulation of ALBHK5 and FTO expression, increasing I-IFN production and the promotion of HSV-1 clearing in HIOECs.

Proteome Comparisons between Hemolymph of Two Honeybee Strains (Apis mellifera ligustica) Reveal Divergent Molecular Basis in Driving Hemolymph Function and High Royal Jelly Secretion.

Hemolymph is vital for the immunity of honeybees and offers a way to investigate their physiological status. To gain novel insight into the functionality and molecular details of the hemolymph in driving increased Royal Jelly (RJ) production, we characterized and compared hemolymph proteomes across the larval and adult ages of Italian bees (ITbs) and Royal Jelly bees (RJbs), a stock selected from ITbs for increasing RJ output. Unprecedented in-depth proteome was attained with the identification of 3394 hemolymph proteins in both bee lines. The changes in proteome support the general function of hemolymph to drive development and immunity across different ages. However, age-specific proteome settings have adapted to prime the distinct physiology for larvae and adult bees. In larvae, the proteome is thought to drive temporal immunity, rapid organogenesis, and reorganization of larval structures. In adults, the proteome plays key roles in prompting tissue development and immune defense in newly emerged bees, in gland maturity in nurse bees, and in carbohydrate energy production in forager bees. Between larval and adult samples of the same age, RJbs and ITbs have tailored distinct hemolymph proteome programs to drive their physiology. In particular, in day 4 larvae and nurse bees, a large number of highly abundant proteins are enriched in protein synthesis and energy metabolism in RJbs. This implies that they have adapted their proteome to initiate different developmental trajectories and high RJ secretion in response to selection for enhanced RJ production. Our hitherto unexplored in-depth proteome coverage provides novel insight into molecular details that drive hemolymph function and high RJ production by RJbs.

Proteomic Analysis Reveals the Molecular Underpinnings of Mandibular Gland Development and Lipid Metabolism in Two Lines of Honeybees (Apis mellifera ligustica).

The mandibular glands (MGs) of honeybee workers are vital for the secretion of lipids, for both larval nutrition and pheromones. However, knowledge of how the proteome controls MG development and functionality at the different physiological stages of worker bees is still lacking. We characterized and compared the proteome across different ages of MGs in Italian bees (ITBs) and Royal Jelly (RJ) bees (RJBs), the latter being a line bred for increasing RJ yield, originating from the ITB. All 2000 proteins that were shared by differently aged MGs in both bee lines (>4000 proteins identified in all) were strongly enriched in metabolizing protein, nucleic acid, small molecule, and lipid functional groups. The fact that these shared proteins are enriched in similar groups in both lines suggests that they are essential for basic cellular maintenance and MG functions. However, great differences were found when comparing the proteome across different MG phases in each line. In newly emerged bees (NEBs), the unique and highly abundant proteins were enriched in protein synthesis, cytoskeleton, and development related functional groups, suggesting their importance to initialize young MG development. In nurse bees (NBs), specific and highly abundant proteins were mainly enriched in substance transport and lipid synthesis, indicating their priority may be in priming high secretory activity in lipid synthesis as larval nutrition. The unique and highly abundant proteins in forager bees (FBs) were enriched in lipid metabolism, small molecule, and carbohydrate metabolism. This indicates their emphasis on 2-heptanone synthesis as an alarm pheromone to enhance colony defense or scent marker for foraging efficiency. Furthermore, a wide range of different biological processes was observed between ITBs and RJBs at different MG ages. Both bee stocks may adapt different proteome programs to drive gland development and functionality. The RJB nurse bee has reshaped its proteome by enhancing the rate of lipid synthesis and minimizing degradation to increase 10-hydroxy-2-decenoic acid synthesis, a major component of RJ, to maintain the desired proportion of lipids in increased RJ production. This study contributes a novel understanding of MG development and lipid metabolism, and a potential starting point for lipid or pheromone biochemists as well as developmental geneticists.

Phosphoproteomic Analysis of Protein Phosphorylation Networks in the Hypopharyngeal Gland of Honeybee Workers (Apis mellifera ligustica).

The hypopharyngeal gland (HG) in honeybee workers changes functions according to physiological age in the bee colony from producing royal jelly (RJ) in nurse bees to digestive enzymes in foragers. The same set of secretory cells expresses different genes or proteins to create these age-dependent changes; however, it is unknown precisely how the phosphorylation network regulates physiological differences across the development of the adult worker HG. We employed high-accuracy mass-spectrometry-based proteomics to survey phosphoproteome changes in the newly emerged, nurse, and forager bees. Overall, 941, 1322, and 1196 phosphorylation sites matching 1007, 1353, and 1199 phosphopeptides from 549, 720, and 698 phosphoproteins were identified in the three ages of the HG, respectively. Specialized, interconnected phosphorylation networks within each age were found by comparing protein abundance and phosphorylation levels. This illustrates that many proteins are regulated by phosphorylation independent of their expression levels. Furthermore, proteins in key biological processes and pathways were dynamically phosphorylated with age development, including the centrosome cycle, mitotic spindle elongation, macromolecular complex disassembly, and ribosome, indicating that phosphorylation tunes protein activity to optimize cellular behavior of the HG over time. Moreover, complementary protein and phosphoprotein expression is required to support the unique physiology of secretory activity in the HG. This reported data set of the honeybee phosphoproteome significantly improves our understanding of a range of regulatory mechanisms controlling a variety of cellular processes and will serve as a valuable resource for those studying the honeybee and other insects.

Quantitative Neuropeptidome Analysis Reveals Neuropeptides Are Correlated with Social Behavior Regulation of the Honeybee Workers.

Neuropeptides play vital roles in orchestrating neural communication and physiological modulation in organisms, acting as neurotransmitters, neuromodulators, and neurohormones. The highly evolved social structure of honeybees is a good system for understanding how neuropeptides regulate social behaviors; however, much knowledge on neuropeptidomic variation in the age-related division of labor remains unknown. An in-depth comparison of the brain neuropeptidomic dynamics over four time points of age-related polyethism was performed on two strains of honeybees, the Italian bee (Apis mellifera ligustica, ITb) and the high royal jelly producing bee (RJb, selected for increasing royal jelly production for almost four decades from the ITb in China). Among the 158 identified nonredundant neuropeptides, 77 were previously unreported, significantly expanding the coverage of the honeybee neuropeptidome. The fact that 14 identical neuropeptide precursors changed their expression levels during the division of labor in both the ITb and RJb indicates they are highly related to task transition of honeybee workers. These observations further suggest the two lines of bees employ a similar neuropeptidome modification to tune their respective physiology of age polyethism via regulating excretory system, circadian clock system, and so forth. Noticeably, the enhanced level of neuropeptides implicated in regulating water homeostasis, brood pheromone recognition, foraging capacity, and pollen collection in RJb signify the fact that neuropeptides are also involved in the regulation of RJ secretion. These findings gain novel understanding of honeybee neuropeptidome correlated with social behavior regulation, which is potentially important in neurobiology for honeybees and other insects.

Proteome Analysis Unravels Mechanism Underling the Embryogenesis of the Honeybee Drone and Its Divergence with the Worker (Apis mellifera lingustica).

The worker and drone bees each contain a separate diploid and haploid genetic makeup, respectively. Mechanisms regulating the embryogenesis of the drone and its mechanistic difference with the worker are still poorly understood. The proteomes of the two embryos at three time-points throughout development were analyzed by applying mass spectrometry-based proteomics. We identified 2788 and 2840 proteins in the worker and drone embryos, respectively. The age-dependent proteome driving the drone embryogenesis generally follows the worker's. The two embryos however evolve a distinct proteome setting to prime their respective embryogenesis. The strongly expressed proteins and pathways related to transcriptional-translational machinery and morphogenesis at 24 h drone embryo relative to the worker, illustrating the earlier occurrence of morphogenesis in the drone than worker. These morphogenesis differences remain through to the middle-late stage in the two embryos. The two embryos employ distinct antioxidant mechanisms coinciding with the temporal-difference organogenesis. The drone embryo's strongly expressed cytoskeletal proteins signify key roles to match its large body size. The RNAi induced knockdown of the ribosomal protein offers evidence for the functional investigation of gene regulating of honeybee embryogenesis. The data significantly expand novel regulatory mechanisms governing the embryogenesis, which is potentially important for honeybee and other insects.

In-Depth N-Glycosylation Reveals Species-Specific Modifications and Functions of the Royal Jelly Protein from Western (Apis mellifera) and Eastern Honeybees (Apis cerana).

Royal jelly (RJ), secreted by honeybee workers, plays diverse roles as nutrients and defense agents for honeybee biology and human health. Despite being reported to be glycoproteins, the glycosylation characterization and functionality of RJ proteins in different honeybee species are largely unknown. An in-depth N-glycoproteome analysis and functional assay of RJ produced by Apis mellifera lingustica (Aml) and Apis cerana cerana (Acc) were conducted. RJ produced by Aml yielded 80 nonredundant N-glycoproteins carrying 190 glycosites, of which 23 novel proteins harboring 35 glycosites were identified. For Acc, all 43 proteins glycosylated at 138 glycosites were reported for the first time. Proteins with distinct N-glycoproteomic characteristics in terms of glycoprotein species, number of N-glycosylated sites, glycosylation motif, abundance level of glycoproteins, and N-glycosites were observed in this two RJ samples. The fact that the low inhibitory efficiency of N-glycosylated major royal jelly protein 2 (MRJP2) against Paenibacillus larvae (P. larvae) and the absence of antibacterial related glycosylated apidaecin, hymenoptaecin, and peritrophic matrix in the Aml RJ compared to Acc reveal the mechanism for why the Aml larvae are susceptible to P. larvae, the causative agent of a fatal brood disease (American foulbrood, AFB). The observed antihypertension activity of N-glycosylated MRJP1 in two RJ samples and a stronger activity found in Acc than in Aml reveal that specific RJ protein and modification are potentially useful for the treatment of hypertensive disease for humans. Our data gain novel understanding that the western and eastern bees have evolved species-specific strategies of glycosylation to fine-tune protein activity for optimizing molecular function as nutrients and immune agents for the good of honeybee and influence on the health promoting activity for human as well. This serves as a valuable resource for the targeted probing of the biological functions of RJ proteins for honeybee and medical communities.

Boosting electrocatalytic performance via electronic structure regulation for acidic oxygen evolution.

High-purity hydrogen produced by water electrolysis has become a sustainable energy carrier. Due to the corrosive environments and strong oxidizing working conditions, the main challenge faced by acidic water oxidation is the decrease in the activity and stability of anodic electrocatalysts. To address this issue, efficient strategies have been developed to design electrocatalysts toward acidic OER with excellent intrinsic performance. Electronic structure modification achieved through defect engineering, doping, alloying, atomic arrangement, surface reconstruction, and constructing metal-support interactions provides an effective means to boost OER. Based on introducing OER mechanism commonly present in acidic environments, this review comprehensively summarizes the effective strategies for regulating the electronic structure to boost the activity and stability of catalytic materials. Finally, several promising research directions are discussed to inspire the design and synthesis of high-performance acidic OER electrocatalysts.

Low concentrations of TNF-α promote osteogenic differentiation via activation of the ephrinB2-EphB4 signalling pathway.

OBJECTIVES: Low concentrations of tumour necrosis factor-alpha (TNF-α) have been reported to promote osteogenic differentiation. In this study, a series of in vitro experiments was performed to investigate underlying molecular mechanisms involved. MATERIALS AND METHODS: MC3T3-E1 murine preosteoblasts were treated with TNF-α at doses of 0, 0.1 or 1 ng/mL. The ephrinB2-EphB4 signalling pathway was activated using ephrinB2-fc, or inhibited using lentiviruses encoding siRNAs specifically targeting EphB4. Cell proliferation/survival was evaluated using the Cell Counting Kit-8 (CCK-8) assay, and expression levels of Runx2, BSP, ephrinB2 and EphB4 were determined using RT-PCR and Western blotting. ALP activity in these cells was also determined, and mineral nodule formation was evaluated with alizarin red S staining. RESULTS: Low concentrations of TNF-α had no influence on cell proliferation/survival. However, expression levels of Runx2, BSP, ephrinB2 and EphB4, as well as ALP activity and mineral nodule formation, were significantly enhanced in MC3T3-E1 cells treated with low concentrations of TNF-α. Moreover, activation of the ephrinB2-EphB4 signalling pathway by ephrinB2-fc enhanced TNF-α-induced osteogenic differentiation, while down-regulation of EphB4 level reversed the positive effect of TNF-α. CONCLUSIONS: Low concentrations of TNF-α promoted osteogenic differentiation via activation of the ephrinB2-EphB4 signalling pathway.

JQ1, a small molecule inhibitor of BRD4, suppresses cell growth and invasion in oral squamous cell carcinoma.

The present study aimed to evaluate whether bromodomain 4 (BRD4) is expressed in Cal27 cells and to assess the effect of JQ1 on cell proliferation, apoptosis, invasion and BRD4, C-Myc and Twist expression in Cal27 cells. Immunofluorescence staining was used to determine whether BRD4 was expressed in Cal27 cells. Cell viability and proliferation were evaluated using CCK-8 assay. Flow cytometry was used to determine the apoptosis and cell cycle distribution. The cell invasion was evaluated using Transwell plate. The expression levels of BRD4, C-Myc and Twist were determined by quantitative RT-PCR (qRT-PCR) and western blotting. BRD4 was highly expressed in Cal27 cells. JQ1 inhibited cell proliferation, induced cell apoptosis, induced cell cycle arrest, and inhibited cell invasion. Gene and protein expression levels of BRD4, C-Myc and Twist were downregulated in cells treated with JQ1. JQ1 inhibited Cal27 cell growth and invasion, and downregulated expression of several oncogenes. JQ1 may be a new drug for oral squamous cell carcinoma treatment.

Functional and Proteomic Investigations Reveal Major Royal Jelly Protein 1 Associated with Anti-hypertension Activity in Mouse Vascular Smooth Muscle Cells.

Vascular smooth muscle cells (VSMCs) are a major cell type of the arterial wall and their functionality is associated with blood pressure regulation. Although royal jelly (RJ) has reported effects on anti-hypertension, the mechanism of blood pressure regulation by major royal jelly protein 1 (MRJP1), the most abundant RJ protein, is still unknown. The mrjp1 gene was inserted into mouse VSMCs to investigate how MRJP1 influences VSMC functionality by functional and proteomic analysis. The expression of MRJP1 in VSMCs significantly reduced cell contraction, migration, and proliferation, suggesting a potential role in decreasing hypertension via action on VSMCs. These anti-hypertension activities were further observed in the changes of the proteome setting of mouse VSMCs. Among 675 different proteins after MRJP1 expression, 646 were down-regulated and significantly enriched in pathways implicated in VSMC contraction and migration, which suggest MRJP1 lowers VSMC contraction and migration by inhibiting muscle filament movement. The down-regulated proteins also enriched pathways in proliferation, indicating that MRJP1 hinders VSMC proliferation by reducing the supply of energy and genetic material. This is the first report integrating MRJP1 into VSMC, revealing the function and mechanism correlated with anti-hypertensive activity. This offers a therapeutic potential to control hypertension by gene-therapy using bee-products.

A case of multiple verruciform xanthoma in gingiva.

We present an unusual case of multiple verruciform xanthomas in the gingiva of a patient with no systemic diseases.

Role of serum IL-23/IL-17 axis in the relationship between periodontitis and coronary heart disease.

To explore the role of the IL-23/IL-17 axis in the relationship between periodontitis and coronary heart disease (CHD), 97 subjects were recruited and divided into four groups: (1) CHD + periodontitis, (2) CHD, (3) periodontitus alone, and (4) healthy. The demographic characteristics and periodontal status of all subjects were recorded, and the serum levels of IL-23/IL-17 were detected by enzyme-linked immunoabsorbent assay. Results showed that the serum levels of IL-23/IL-17 in groups 1, 2, and 3 were higher compared with group 4. Group 1 manifested the highest level of serum IL-23/IL-17. A significant positive correlation between IL-23 and IL-17 levels was seen in the three patients groups; groups 1 and 3 also had significant positive correlations with probing depth and attachment loss. The results indicate that there may be an association between periodontitis and CHD, and the IL-23/IL-17 axis may play an important role in the pathologic process of both diseases.

[High-level transcription of human mitochondrial tRNA(Trp) based on ribozyme and characterization on its aminoacylation activity].

In vitro transcription systems with T7 RNA polymerase (T7 RNAP) were widely used in preparation of RNA because of their simplicity and high efficiency. The transcripts would have additional 5' sequence since T7 promoter spans the transcription start site, while deletion of the transcription start site would severely reduce the T7 RNAP transcriptional activity. We successfully developed an in vitro transcription by combining of T7 RNAP high efficient transcription system and highly specific self-splicing technology of ribozymes, in this system, ribozyme self-splices at the designed specific site and releases the aim RNA without affecting transcription efficiency of T7 RNAP, the aminoacylation activity of human mitochondrial tRNA(Trp) (HmtRNA(Trp) (UCA)) is 113.6 pmol/microg. This method with its high efficiency on transcription and good repeatability is very suitable for preparation of accurate RNA in large scale.