Haplotype-resolved 3D chromatin architecture of the hybrid pig.

In diploid mammals, allele-specific three-dimensional (3D) genome architecture may lead to imbalanced gene expression. Through ultradeep in situ Hi-C sequencing of three representative somatic tissues (liver, skeletal muscle, and brain) from hybrid pigs generated by reciprocal crosses of phenotypically and physiologically divergent Berkshire and Tibetan pigs, we uncover extensive chromatin reorganization between homologous chromosomes across multiple scales. Haplotype-based interrogation of multi-omic data revealed the tissue dependence of 3D chromatin conformation, suggesting that parent-of-origin-specific conformation may drive gene imprinting. We quantify the effects of genetic variations and histone modifications on allelic differences of long-range promoter-enhancer contacts, which likely contribute to the phenotypic differences between the parental pig breeds. We also observe the fine structure of somatically paired homologous chromosomes in the pig genome, which has a functional implication genome-wide. This work illustrates how allele-specific chromatin architecture facilitates concomitant shifts in allele-biased gene expression, as well as the possible consequential phenotypic changes in mammals.

Modulation of fatty acid elongation in cockroaches sustains sexually dimorphic hydrocarbons and female attractiveness.

Insect cuticular hydrocarbons (CHCs) serve as important intersexual signaling chemicals and generally show variation between the sexes, but little is known about the generation of sexually dimorphic hydrocarbons (SDHCs) in insects. In this study, we report the molecular mechanism and biological significance that underlie the generation of SDHC in the German cockroach Blattella germanica. Sexually mature females possess more C29 CHCs, especially the contact sex pheromone precursor 3,11-DimeC29. RNA interference (RNAi) screen against the fatty acid elongase family members combined with heterologous expression of the genes in yeast revealed that both BgElo12 and BgElo24 were involved in hydrocarbon (HC) production, but BgElo24 is of wide catalytic activities and is able to provide substrates for BgElo12, and only the female-enriched BgElo12 is responsible for sustaining female-specific HC profile. Repressing BgElo12 masculinized the female CHC profile, decreased contact sex pheromone level, and consequently reduced the sexual attractiveness of female cockroaches. Moreover, the asymmetric expression of BgElo12 between the sexes is modulated by sex differentiation cascade. Specifically, male-specific BgDsx represses the transcription of BgElo12 in males, while BgTra is able to remove this effect in females. Our study reveals a novel molecular mechanism responsible for the formation of SDHCs and also provide evidences on shaping of the SDHCs by sexual selection, as females use them to generate high levels of contact sex pheromone.

Genetic Underpinnings of Cuticular Hydrocarbon Biosynthesis in the German Cockroach, Blattella germanica (L.): Progress and Perspectives.

Insect cuticular hydrocarbons (CHCs) serve as important waterproofing barriers and as signals and cues in chemical communication. Over the past 30 years, numerous studies on CHCs have been conducted in the German cockroach, Blattella germanica, leading to substantial progress in the field. However, there has not been a systematic review of CHC studies in this species in recent years. This review aims to provide a concise overview of the chemical composition, storage, transport, and physical properties of different CHCs in B. germanica. Additionally, we focus on the biosynthetic pathway and the genetic regulation of HC biosynthesis in this species. A considerable amount of biochemical evidence regarding the biosynthetic pathway of insect CHCs has been gathered from studies conducted in B. germanica. In recent years, there has also been an improved understanding of the molecular mechanisms that underlie CHC production in this insect. In this article, we summarize the biosynthesis of different classes of CHCs in B. germanica. Then, we review CHCs reaction to various environmental conditions and stressors and internal physiological states. Additionally, we review a body of work showing that in B. germanica, CHC profiles exhibit significant sexual dimorphism, specific CHCs act as essential precursors for female contact sex pheromone components, and we summarize the molecular regulatory mechanisms that underlie sexual dimorphism of CHC profiles. Finally, we highlight future directions and challenges in research on the biosynthesis and regulatory mechanisms of CHCs in B. germanica, and also identify potential applications of CHC studies in the pest control.

Cuticular Hydrocarbon Plasticity in Three Rice Planthopper Species.

Insect cuticular hydrocarbons (CHCs) are organic compounds of the surface lipid layer, which function as a barrier against water loss and xenobiotic penetration, while also serving as chemical signals. Plasticity of CHC profiles can vary depending upon numerous biological and environmental factors. Here, we investigated potential sources of variation in CHC profiles of Nilaparvata lugens, Laodelphax striatellus and Sogatella furcifera, which are considered to be the most important rice pests in Asia. CHC profiles were quantified by GC/MS, and factors associated with variations were explored by conducting principal component analysis (PCA). Transcriptomes were further compared under different environmental conditions. The results demonstrated that CHC profiles differ among three species and change with different developmental stages, sexes, temperature, humidity and host plants. Genes involved in cuticular lipid biosynthesis pathways are modulated, which might explain why CHC profiles vary among species under different environments. Our study illustrates some biological and ecological variations in modifying CHC profiles, and the underlying molecular regulation mechanisms of the planthoppers in coping with changes of environmental conditions, which is of great importance for identifying potential vulnerabilities relating to pest ecology and developing novel pest management strategies.

Screening candidate microR-15a- IRAK2 regulatory pairs for predicting the response to Staphylococcus aureus-induced mastitis in dairy cows.

We established a mastitis model using exogenous infection of the mammary gland of Chinese Holstein cows with Staphylococcus aureus and extracted total RNA from S. aureus-infected and healthy mammary quarters. Differential expression of genes due to mastitis was evaluated using Affymetrix technology and results revealed a total of 1230 differentially expressed mRNAs. A subset of affected genes was verified via Q-PCR and pathway analysis. In addition, Solexa high-throughput sequencing technology was used to analyze profiles of miRNA in infected and healthy quarters. These analyses revealed a total of 52 differentially expressed miRNAs. A subset of those results was verified via Q-PCR. Bioinformatics techniques were used to predict and analyze the correlations among differentially expressed miRNA and mRNA. Results revealed a total of 329 pairs of negatively associated miRNA/mRNA, with 31 upregulated pairs of mRNA and 298 downregulated pairs of mRNA. Differential expression of miR-15a and interleukin-1 receptor-associated kinase-like 2 (IRAK2), were evaluated by western blot and luciferase reporter assays. We conclude that miR-15a and miR-15a target genes (IRAK2) constitute potential miRNA-mRNA regulatory pairs for use as biomarkers to predict a mastitis response.

Hyperlipidemia induces vascular smooth muscle cell proliferation involving Wnt/ß-catenin signaling.

Hyperlipidemia has been shown to stimulate vascular smooth muscle cell (VSMC) proliferation. Wnt signaling pathway plays a critical role in embryonic development and cell proliferation. In this study, Sprague-Dawley rats fed with high-fat or normal diet for 12 weeks were sacrificed, and the thoracic aorta was harvested to determine wnt3a, ß-catenin, T-cell factor 4 (TCF4), and cyclin D1 expressions. VSMC proliferation within thoracic aorta and lipid accumulation within VSMCs were detected. Rat aortic VSMCs were cultured in serum from rats with hyperlipidemia or DKK-1; Wnt3a, ß-catenin, TCF4, and cyclin D1 expressions, and cell cycle distribution were determined. The findings demonstrated that increased number of VSMCs, lipid droplets, and vacuoles within thoracic aorta in the high-fat-fed group. Compared with controls, VSMCs from high-fat-fed rats showed higher mRNA expressions of wnt3a, ß-catenin, TCF4, and cyclin D1, as well as in VSMCs cultured with hyperlipidemic serum. After 24 h, VSMCs stimulated with hyperlipidemic serum showed significantly increased cell number and S-phase entry compared with cells exposed to normolipidemic serum. These effects were blocked by DKK-1. These results suggest that Wnt/ß-catenin signaling plays an important role in hyperlipidemia-induced VSMC proliferation.

Large-area ordered Ge-Si compound quantum dot molecules on dot-patterned Si (001) substrates.

We report on the formation of large-area ordered Ge-Si compound quantum dot molecules (CQDMs) in a combination of nanosphere lithography and self-assembly. Truncated-pyramid-like Si dots with {11n} facets are readily formed, which are spatially ordered in a large area with controlled period and size. Each Si dot induces four self-assembled Ge-rich dots at its base edges that can be fourfold symmetric along <110> directions. A model based on surface chemical potential accounts well for these phenomena. Our results disclose the critical effect of surface curvature on the diffusion and the aggregation of Ge adatoms and shed new light on the unique features and the inherent mechanism of self-assembled QDs on patterned substrates. Such a configuration of one Si QD surrounded by fourfold symmetric Ge-rich QDs can be seen as a CQDM with unique features, which will have potential applications in novel devices.

Fabrication and characterization of SiGe coaxial quantum wells on ordered Si nanopillars.

Controlled SiGe coaxial quantum wells (CQWs) on periodic Si(001) nanopillars in a large area are explored systematically. The periodic SiGe CQW nanopillars are fabricated by a combination of nanosphere lithography, metal assisted chemical etching and epitaxial growth. The period, the radius, the height, the composition and the thickness of the SiGe alloy layer can all be intentionally modified. Considerably enhanced photoluminescence (PL) from the SiGe CQW nanopillars is observed, which is composed of four peaks. Such PL features are explained by the coupling between the spontaneous emissions of the SiGe CQW and the Mie resonant modes of the nanopillars, which can be further improved by optimizing the structural parameters of the SiGe CQW and the nanopillars. Our results demonstrate a feasible route to obtaining controlled SiGe CQW nanopillars, which have potential applications in optoelectronic devices.

Acetyl coenzyme A carboxylase modulates lipogenesis and sugar homeostasis in Blattella germanica.

Lipid and sugar homeostasis is critical for insect development and survival. In this study, we characterized an acetyl coenzyme A carboxylase gene in Blattella germanica (BgACC) that is involved in both lipogenesis and sugar homeostasis. We found that BgACC was dominantly expressed in the fat body and integument, and was significantly upregulated after molting. Knockdown of BgACC in 5th-instar nymphs did not affect their normal molting to the next nymphal stage, but it caused a lethal phenotype during adult emergence. BgACC-RNA interference (RNAi) significantly downregulated total free fatty acid (FFA) and triacylglycerol (TAG) levels, and also caused a significant decrease of cuticular hydrocarbons (CHCs). Repression of BgACC in adult females affected the development of oocytes and resulted in sterile females, but BgACC-RNAi did not affect the reproductive ability of males. Interestingly, knockdown of BgACC also changed the expression of insulin-like peptide genes (BgILPs), which mimicked a physiological state of high sugar uptake. In addition, BgACC was upregulated when B. germanica were fed on a high sucrose diet, and repression of BgACC upregulated the expression of the glycogen synthase gene (BgGlyS). Moreover, BgACC-RNAi increased the circulating sugar levels and glycogen storage, and a longevity assay suggested that BgACC was important for the survival of B. germanica under conditions of high sucrose uptake. Our results confirm that BgACC is involved in multiple lipid biogenesis and sugar homeostasis processes, which further modulates insect reproduction and sugar tolerance. This study benefits our understanding of the crosstalk between lipid and sugar metabolism.

Endovascular repair combined with in situ fenestration for new-onset or residual arch dissection in patients underwent aortic replacement.

INTRODUCTION: Ascending aorta or hemi-arch replacement is a frequently used treatment for patients with acute type A thoracic aortic dissection, particularly those who are elderly or have multiple comorbidities. However, in cases where there are secondary entry tears in the aortic arch or descending aorta, this procedure may not fully resolve the issue. The true lumen may remain compressed due to perfusion of the false lumen and usually require reoperation. METHODS: Between January 2019 and July 2022, 18 patients underwent endovascular total aortic arch repair and fenestration technique without requiring median re-sternotomy. Aortic stent grafts were implanted via the femoral approach, utilizing prosthetic vessels as an appropriate proximal landing zone for aortic stent graft deployment. Based on the debranching conditions of the arch in previous surgery, single, double or triple in situ fenestrations (ISFs) were performed, respectively. RESULTS: All 18 cases were technically successful, with a median follow-up period of 20 months (range: 18-31 months). All patients had a favourable postoperative course, with no deaths within 30 days or during their hospital stay. There were no instances of disabling stroke, paraplegia, endo-leak, stent graft migration or stent graft-induced new entry. In addition, all patients exhibited complete thrombosis of the false lumen at the level of the aortic arch. CONCLUSION: Our preliminary experience suggests that endovascular total arch repair combined with ISF technique is a viable, effective and safe option for treatment. Our mid-term results have been promising, but we acknowledge the need for further evaluation to assess long-term outcomes and durability.

Two sex pheromone receptors for sexual communication in the American cockroach.

Volatile sex pheromones are vital for sexual communication between males and females. Females of the American cockroach, Periplaneta americana, produce and emit two sex pheromone components, periplanone-A (PA) and periplanone-B (PB). Although PB is the major sex attractant and can attract males, how it interacts with PA in regulating sexual behaviors is still unknown. In this study, we found that in male cockroaches, PA counteracted PB attraction. We identified two odorant receptors (ORs), OR53 and OR100, as PB/PA and PA receptors, respectively. OR53 and OR100 were predominantly expressed in the antennae of sexually mature males, and their expression levels were regulated by the sex differentiation pathway and nutrition-responsive signals. Cellular localization of OR53 and OR100 in male antennae further revealed that two types of sensilla coordinate a complex two-pheromone-two-receptor pathway in regulating cockroach sexual behaviors. These findings indicate distinct functions of the two sex pheromone components, identify their receptors and possible regulatory mechanisms underlying the male-specific and age-dependent sexual behaviors, and can guide novel strategies for pest management.

Proteomic analysis of an unculturable bacterial endosymbiont (Blochmannia) reveals high abundance of chaperonins and biosynthetic enzymes.

Many insect groups have coevolved with bacterial endosymbionts that live within specialized host cells. As a salient example, ants in the tribe Camponotini rely on Blochmannia, an intracellular bacterial mutualist that synthesizes amino acids and recycles nitrogen for the host. We performed a shotgun, label-free, LC/MS/MS quantitative proteomic analysis to investigate the proteome of Blochmannia associated with Camponotus chromaiodes. We identified more than 330 Blochmannia proteins, or 54% coverage of the predicted proteome, as well as 244 Camponotus proteins. Using the average intensity of the top 3 "best flier" peptides along with spiking of a surrogate standard at a known concentration, we estimated the concentration (fmol/µg) of those proteins with confident identification. The estimated dynamic range of Blochmannia protein abundance spanned 3 orders of magnitude and covered diverse functional categories, with particularly high representation of metabolism, information transfer, and chaperones. GroEL, the most abundant protein, totaled 6% of Blochmannia protein abundance. Biosynthesis of essential amino acids, fatty acids, and nucleotides, and sulfate assimilation had disproportionately high coverage in the proteome, further supporting a nutritional role of the symbiosis. This first quantitative proteomic analysis of an ant endosymbiont illustrates a promising approach to study the functional basis of intimate symbioses.

Optical properties of coupled three-dimensional Ge quantum dot crystals.

We report on optical properties of coupled three-dimensional (3D) Ge quantum dot crystals (QDCs). With increasing the vertical periodic number of the QDCs, the photoluminescence (PL) spectral linewidth decreased exponentially, and so did the peak energy blueshift caused by increasing excitation power, which are attributed to the electronic coupling and thus the formation of miniband. In the PL spectra, the relative intensity of the transverse-optical (TO) phonon replica also decreases with increasing the vertical periodic number, which is attributed to the increased Brillouin-zone folding effect in vertical direction and therewith the relaxation of indirect transition nature of exciton recombination. Besides, the optical reflectivity at the interband transition energy was much more reduced for the QDCs than for the in-plane disordered QDs grown with the same parameters, indicating a higher interband absorption of the QDCs due to the miniband formation.

Can't take the heat: high temperature depletes bacterial endosymbionts of ants.

Members of the ant tribe Camponotini have coevolved with Blochmannia, an obligate intracellular bacterial mutualist. This endosymbiont lives within host bacteriocyte cells that line the ant midgut, undergoes maternal transmission from host queens to offspring, and contributes to host nutrition via nitrogen recycling and nutrient biosynthesis. While elevated temperature has been shown to disrupt obligate bacterial mutualists of some insects, its impact on the ant-Blochmannia partnership is less clear. Here, we test the effect of heat on the density of Blochmannia in two related Camponotus species in the lab. Transcriptionally active Blochmannia were quantified using RT-qPCR as the ratio of Blochmannia 16S rRNA to ant host elongation factor 1-α transcripts. Our results showed that 4 weeks of heat treatment depleted active Blochmannia by >99 % in minor workers and unmated queens. However, complete elimination of Blochmannia transcripts rarely occurred, even after 16 weeks of heat treatment. Possible mechanisms of observed thermal sensitivity may include extreme AT-richness and related features of Blochmannia genomes, as well as host stress responses. Broadly, the observed depletion of an essential microbial mutualist in heat-treated ants is analogous to the loss of zooanthellae during coral bleaching. While the ecological relevance of Blochmannia's thermal sensitivity is uncertain, our results argue that symbiont dynamics should be part of models predicting how ants and other animals will respond and adapt to a warming climate.

Proteome Analysis of Male Accessory Gland Secretions in the Diamondback Moth, Plutella xylostella (Lepidoptera: Plutellidae).

In insects, male accessory gland proteins (ACPs) are important reproductive proteins secreted by male accessory glands (MAGs) of the internal male reproductive system. During mating, ACPs are transferred along with sperms inside female bodies and have a significant impact on the post-mating physiology changes of the females. Under sexual selection pressures, the ACPs exhibit remarkably rapid and divergent evolution and vary from species to species. The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major insect pest of cruciferous vegetables worldwide. Mating has a profound impact on the females' behavior and physiology in this species. It is still unclear what the ACPs are in this species. In this study, two different proteomic methods were used to identify ACPs in P. xylostella. The proteins of MAGs were compared immediately before and after mating by using a tandem mass tags (TMT) quantitative proteomic analysis. The proteomes of copulatory bursas (CB) in mated females shortly after mating were also analyzed by the shotgun LC-MS/MS technique. In total, we identified 123 putative secreted ACPs. Comparing P. xylostella with other four insect ACPs, trypsins were the only ACPs detected in all insect species. We also identified some new insect ACPs, including proteins with chitin binding Peritrophin-A domain, PMP-22/ EMP/ MP20/ Claudin tight junction domain-containing protein, netrin-1, type II inositol 1,4,5-trisphosphate 5-phosphatase, two spaetzles, allatostatin-CC, and cuticular protein. This is the first time that ACPs have been identified and analyzed in P. xylostella. Our results have provided an important list of putative secreted ACPs, and have set the stage for further exploration of the functions of these putative proteins in P. xylostella reproduction.

A cell transcriptomic profile provides insights into adipocytes of porcine mammary gland across development.

BACKGROUND: Studying the composition and developmental mechanisms in mammary gland is crucial for healthy growth of newborns. The mammary gland is inherently heterogeneous, and its physiological function dependents on the gene expression of multiple cell types. Most studies focused on epithelial cells, disregarding the role of neighboring adipocytes. RESULTS: Here, we constructed the largest transcriptomic dataset of porcine mammary gland cells thus far. The dataset captured 126,829 high-quality nuclei from physiological mammary glands across five developmental stages (d 90 of gestation, G90; d 0 after lactation, L0; d 20 after lactation, L20; 2 d post natural involution, PI2; 7 d post natural involution, PI7). Seven cell types were identified, including epithelial cells, adipocytes, endothelial cells, fibroblasts cells, immune cells, myoepithelial cells and precursor cells. Our data indicate that mammary glands at different developmental stages have distinct phenotypic and transcriptional signatures. During late gestation (G90), the differentiation and proliferation of adipocytes were inhibited. Meanwhile, partly epithelial cells were completely differentiated. Pseudo-time analysis showed that epithelial cells undergo three stages to achieve lactation, including cellular differentiation, hormone sensing, and metabolic activation. During lactation (L0 and L20), adipocytes area accounts for less than 0.5% of mammary glands. To maintain their own survival, the adipocyte exhibited a poorly differentiated state and a proliferative capacity. Epithelial cells initiate lactation upon hormonal stimulation. After fulfilling lactation mission, their undergo physiological death under high intensity lactation. Interestingly, the physiological dead cells seem to be actively cleared by immune cells via CCL21-ACKR4 pathway. This biological process may be an important mechanism for maintaining homeostasis of the mammary gland. During natural involution (PI2 and PI7), epithelial cell populations dedifferentiate into mesenchymal stem cells to maintain the lactation potential of mammary glands for the next lactation cycle. CONCLUSION: The molecular mechanisms of dedifferentiation, proliferation and redifferentiation of adipocytes and epithelial cells were revealed from late pregnancy to natural involution. This cell transcriptomic profile constitutes an essential reference for future studies in the development and remodeling of the mammary gland at different stages.

Fabrication of crystal α-Si3N4/Si-SiOx core-shell/Au-SiOx peapod-like axial double heterostructures for optoelectronic applications.

Novel crystal α-Si(3)N(4)/Si-SiO(x) core-shell/Au-SiO(x) peapod-like axial double heterostructural nanowires were obtained by directly annealing a Au covered SiO(2) thin film on a Si substrate. Our extensive electron microscopic investigation revealed that the α-Si(3)N(4) sections with a mathematical left angle bracket 101 mathematical right angle bracket growth direction were grown first, followed by growth of the Si-SiO(x) core-shell sections and finally growth of the Au-SiO(x) peapod-like sections. Through a series of systematically comparative experiments, a temperature-dependent multi-step vapor-liquid-solid growth mechanism is proposed. Room temperature photoluminescence measurement of individual nanowires reveals two emission peaks (410 and 515 nm), indicating their potential applications in light sources, laser or light emitting display devices.

A prodrug hydrogel with tumor microenvironment and near-infrared light dual-responsive action for synergistic cancer immunotherapy.

Immunotherapy has been used for cancer treatment, while it faces the common dilemmas of low therapeutic efficacy and serious immunotoxicity. In this study, we report the construction of a tumor microenvironment and near-infrared (NIR) light dual-responsive prodrug hydrogel for cancer synergistic immunotherapy in a more effective and safe manner. Such prodrug hydrogels were in-situ formed via calcium-induced gelation of alginate solution containing protoporphyrin IX (PpIX)-modified iron oxide (Fe3O4) nanoparticles and programmed death ligand 1 antibody (aPD-L1) prodrug nanoparticles crosslinked by reactive oxygen species (ROS)-responsive linkers. PpIX served as a photosensitizer to produce singlet oxygen (1O2) under NIR laser irradiation for photodynamic therapy (PDT), and Fe3O4 nanoparticles mediated chemodynamic therapy (CDT) to generate hydroxyl radical (·OH) via Fenton reaction in the tumor microenvironment. In view of the cumulative actions of PDT and CDT, amplified ROS was generated to not only induce immunogenic cell death (ICD), but also destroy ROS-responsive linkers to achieve on-demand release of aPD-L1 from prodrug nanoparticles. Boosted antitumor immunity was elicited in tumor-bearing mice due to the aPD-L1-mediated immune checkpoint blocking. As a result, the prodrug hydrogel-based synergistic immunotherapy could almost treat bilateral tumors and prevent lung and liver metastasis using 4T1 tumor mouse models. This study thus offers a dual-responsive prodrug hydrogel platform for precision cancer immunotherapy. STATEMENT OF SIGNIFICANCE: Via calcium-induced gelation of alginate, we constructed a prodrug hydrogel with tumor microenvironment and near-infrared light dual-responsive action for synergistic cancer immunotherapy. Such hydrogels can achieve on-demand release of aPD-L1 upon photoactivation in the tumor microenvironment. Through mediating photodynamic and chemodynamic therapy, the prodrug hydrogels can induce enhanced immunogenic cell death and synergistically improve the efficacy of aPD-L1-mediated immune checkpoint blocking. The prodrug hydrogel-based synergistic therapy almost deracinates the primary and distant tumors, and prevents lung and liver metastasis in tumor mouse models.

Melanin synthesis genes BgTH and BgDdc affect body color and cuticle permeability in Blattella germanica.

Melanin is involved in cuticle pigmentation and sclerotization of insects, which is critical for maintaining structural integrity and functional completeness of insect cuticle. The 2 key enzymes of tyrosine hydroxylase (TH) and dopa decarboxylase (DDC) predicted in melanin biosynthesis are usually conserved in insects. However, it is unclear whether their function is related to epidermal permeability. In this study, we identified and cloned the gene sequences of BgTH and BgDdc from Blattella germanica, and revealed that they both showed a high expression at the molting, and BgTH was abundant in the head and integument while BgDdc was expressed highest in the fat body. Using RNA interference (RNAi), we found that knockdown of BgTH caused molting obstacles in some cockroaches, with the survivors showing pale color and softer integuments, while knockdown of BgDdc was viable and generated an abnormal light brown body color. Desiccation assay showed that the dsBgTH-injected adults died earlier than control groups under a dry atmosphere, but dsBgDdc-injected cockroaches did not. In contrast, when dsRNA-treated cockroaches were reared under a high humidity condition, almost no cockroaches died in all treatments. Furthermore, with eosin Y staining assay, we found that BgTH-RNAi resulted in a higher cuticular permeability, and BgDdc-RNAi also caused slight dye penetration. These results demonstrate that BgTH and BgDdc function in body pigmentation and affect the waterproofing ability of the cuticle, and the reduction of cuticular permeability may be achieved through cuticle melanization.

MiR-375-3p Promotes Cardiac Fibrosis by Regulating the Ferroptosis Mediated by GPX4.

Although coronary artery recanalization after myocardial infarction improves patient outcomes, inadequate ventricular remodeling following ischemia-reperfusion (IR) injury and secondary cardiac fibrosis (CF) are common and can lead to heart failure. MicroRNAs (miRNAs) play an important role in cardiovascular disorders. However, the underlying molecular mechanism of miRNAs in the occurrence and progression of CF has not been fully elucidated. Herein, through the construction of an I/R rat model and an angiotensin II-induced CF cell model, we evaluated the role of miR-375-3p in the progression of CF. In the I/R rat model and CF cell model, miR-375-3p promoted fibrosis by accelerating the ferroptosis of cardiomyocytes through mediating glutathione peroxidase 4 (GPX4). Furthermore, we treated the rats or cell model with miR-375-3p antagomir (or inhibitor) and ferroptosis inhibitor Ferrostatin-1 (Fer-1). The results showed that miR-375-3p antagomir (or inhibitor) and Fer-1 promoted the antioxidant capacity of cardiac fibroblasts, reduced GPX4-mediated ferroptosis process and alleviated I/R-induced CF. In conclusion, this study revealed that miR-375-3p directly targeted GPX4-an inhibitor of the ferroptosis pathway. Meanwhile, miR-375-3p can be a new potential biomarker for the prevention and treatment of CF.