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Biology subjects

Hao, D.

Publications and source records attributed to Hao, D..

At least 19 recordsLinked to original sources

Identification of scavenger receptor BI as a scavenger of free heme that is essential for protection against hemolysis

Severe hemolysis is a life-threatening condition with limited therapeutic options. Although haptoglobin and hemopexin sequester hemoglobin and heme, these protective systems are rapidly saturated during acute hemolysis, leading to the accumulation of cytotoxic free heme. In this study, we identify scavenger receptor BI (SR-BI) as a critical mediator of free heme clearance. SR-BI binds heme and facilitates its hepatic uptake under pathological conditions. Mice lacking hepatic SR-BI exhibit impaired heme clearance and increased susceptibility to heme- and hemolysis-induced lethality. Pharmacological upregulation of hepatic SR-BI via imatinib or adenoviral delivery confers protection against heme toxicity. Using a humanized model of sickle cell disease (SCD), we further demonstrate that sickle hepatopathy significantly reduces hepatic SR-BI expression compared to non-SCD littermates, potentially increasing vulnerability to heme-induced injury. Notably, adenoviral-mediated SR-BI upregulation rescues SCD mice from heme toxicity. These findings reveal a previously unrecognized mechanism of heme detoxification via hepatic SR-BI and identify a promising therapeutic target for hemolytic disorders. One-Sentence SummaryIdentification of scavenger receptor BI as a targetable scavenger of heme in hemolysis

physiology↗

Sex-specific Genetic Regulatory Effects in Chickens

Sexual dimorphism is a defining vertebrate feature, yet its sex-specific molecular architecture remains poorly understood. Here we established a sex-balanced, uniformly reared chicken cohort to map this landscape, integrating individual whole-genome sequencing with 7,969 bulk and 779,380 single nucleus transcriptomes across 32 tissues from 280 birds. We identified 495,098 independent expression quantitative trait loci for 20,194 genes, including 10,937 loci modulated by cell-type composition. Notably, 340 genes were regulated by 449 loci in a sex-dependent manner, significantly enrichment in endocrine tissues like adipose and the adrenal gland. Furthermore, we fine-mapped 1,219 structural variants, demonstrating their unique roles to tissue- and sex-specific expression beyond SNPs. Ultimately, we showed the utility of these regulatory effects in elucidating the molecular basis of metabolism and complex traits in both chickens and humans. This comprehensive atlas of regulatory effects provides profound insights into the genomic and molecular basis of sexual dimorphism in vertebrates.

genomics↗

Near completely reversing the γ- to β-globin switch by enhancer release, retargeting and reinforcing

The {gamma}- to {beta}-globin switch is intricately regulated during human ontogeny, and this process is manipulated for therapeutic approaches to treat {beta}-hemoglobinopathies by activating {gamma}-globin expression. Several genetic strategies to reactivate HbF have partially reversed the {gamma}- to {beta}-globin switch and ameliorated the clinical symptoms of {beta}-hemoglobinopathies. However, whether the {gamma}- to {beta}-globin switch can be completely reversed remains unknown. Completely reversing the {gamma}- to {beta}-globin switch requires a thorough redirection of the locus control region (LCR) from interacting with the {beta}-globin gene (HBB) to interacting with the {gamma}-globin gene (HBG). Here, we found that disrupting the KLF1-mediated HBB-LCR interaction by mutating the CACCC motif in HBB leads to the release of the LCR and its retargeting to other {beta}-like globin genes. Moreover, simultaneously disrupting the KLF1-mediated HBB-LCR interaction and the epigenetic repression of HBG by combined editing of the CACCC motif in HBB and the TGACCA motif in HBG reinforces the HBG-LCR interaction, resulting in almost exclusive {gamma}-globin expression while nearly absent {beta}-globin expression, achieving near complete reversal of the {gamma}- to {beta}-globin switch. This finding demonstrates the comprehensive regulation of the {gamma}- to {beta}-globin switch by gene competition and gene silencing mechanisms. This finding also suggests that silenced genes can be fully activated through the redirection of enhancer-promoter contacts and that the specificity of enhancer-promoter contact within chromosomal domains is achieved through the transcription factor clusters binding to enhancers and promoters. Combined editing of the CACCC&TGACCA motifs also offer a more optimal therapeutic strategy for {beta}-hemoglobinopathies.

molecular biology↗

The functional divergence of two ethylene receptor subfamilies that exhibit Ca2+-permeable channel activity

Ethylene is a gaseous plant hormone crucial for regulating plant growth, development, and stress adaptation, yet the molecular basis underlying ethylene receptor function remains elusive. Here, we show that subfamily I receptors constitute core ethylene-sensing module and function epistatically to subfamily II receptors. Notably, we discover that only subfamily I receptors possess Ca2+-permeable channel activity, which are indispensable for ethylene-induced cytosolic calcium influx. Overall, this work supports a mechanistic framework in which subfamily I receptors integrate ethylene sensing with Ca2+ influx, providing new insight into how plants translate hormonal cues into downstream signaling events.

plant biology↗

Elevated plasma cholesterol causally improves sepsis outcome by promoting hepatic metabolic reprogramming

RationaleSepsis is a life-threatening condition with high mortality and limited therapeutic options. While hypocholesterolemia is associated with poor outcomes, the causal role of cholesterol and its underlying mechanisms remain unclear. ObjectivesTo determine whether elevated plasma cholesterol improves sepsis survival and to elucidate the mechanistic basis of this effect. MethodsWe analyzed septic patients from the MIMIC-IV database. Total cholesterol levels were compared between 28-day survivors and non-survivors using Wilcoxon rank-sum tests. Cox proportional hazards regression assessed the association between cholesterol levels and mortality, adjusting for age, sex, race, SOFA score, and Charlson comorbidity index. To establish causality, C57BL/6J mice were randomized to receive either a high-cholesterol diet (HCD) or regular diet (RD) for three days prior to cecal ligation and puncture (CLP) to induce sepsis. Measurements and Main ResultsSurvivors had significantly higher cholesterol levels than non-survivors (median, 135 vs. 126 mg/dL, p < 0.001). High cholesterol ([&ge;] 133 mg/dL) was independently associated with reduced 28-day mortality (adjusted HR = 0.80, 95% CI: 0.67-0.95, p = 0.012). In mice, HCD elevated plasma cholesterol and significantly improved survival (52.5% to 90%), independent of immune modulation.Hepatic transcriptomics revealed metabolic reprogramming, including upregulation of oxidative phosphorylation and glutathione-mediated antioxidant pathways, and suppression of endoplasmic reticulum proteostasis. Notably, inhibition of mitochondrial respiration abolished the survival benefit. ConclusionsElevated plasma cholesterol causally improves sepsis outcomes by promoting hepatic metabolic reprogramming. These findings offer mechanistic insight into clinical observations and suggest hepatic bioenergetics as a novel therapeutic target in sepsis.

physiology↗

A newly identified Duck orbivirus as the etiological agent of egg-production decline in Chinese breeder ducks

The genus Orbivirus comprises double-stranded RNA viruses, many of which are transmitted by arthropods and cause febrile, hemorrhagic, or reproductive diseases in animals. In recent years, unexplained outbreaks characterized by marked egg-production decline have occurred in breeder duck flocks in China. To identify the causative agent, samples were collected from affected farms in multiple regions across China between 2022 and 2025. Representative samples were analyzed by high-throughput sequencing, followed by phylogenetic analysis, transmission electron microscopy, host cell infection assays, and animal challenge experiments. A previously unreported Orbivirus, designated Duck orbivirus (DORV), was identified. Epidemiological investigation indicated that outbreaks mainly affected breeder ducks during the peak laying period (21-55 weeks of age), with higher incidence in summer and autumn. The DORV genome contains ten double-stranded RNA segments encoding seven structural and five nonstructural proteins. Phylogenetic analysis showed that DORV is closely related to Parrys Lagoon virus (PLV) and Corriparta virus (CORV). Electron microscopy revealed icosahedral particles 30-40 nm in diameter. DORV replicated efficiently in DEF, DEL and C6/36 cells but not in MDCK and LMH cells, suggesting a restricted host range with potential arthropod-borne features. Infection of breeder ducks with DORV-SD01 reduced egg production by 30-40% and caused lesions in the ovary, liver, and spleen. This study describes a novel duck-origin Orbivirus linked to egg-production decline, offering new etiological insights and extending the host spectrum of Orbivirus. The results provide a foundation for future surveillance and prevention of emerging waterfowl diseases.

microbiology↗

Functional Role of Small Extrachromosomal Circular DNA in Colorectal Cancer

Extrachromosomal circular DNA (eccDNA) are circular DNA molecules that originate from chromosomal DNA but exist independently. While large eccDNA (ecDNA) contributes to tumorigenesis, the role of smaller eccDNA (<100,000 base pairs) in cancer remains unclear. Our analysis of 25 colorectal cancer (CRC) tumors and adjacent non-tumorous tissues revealed that eccDNA is significantly more abundant in tumor tissues, correlating strongly with chromosomal amplifications. The presence of whole intact genes on 1.29% of eccDNA was non-random. We identified 84 genes that recurred across tumors of multiple patients when present on eccDNA with 19% of genes being cancer-associated. eccDNA-borne genes were often accompanied by increased expression, and their contribution to expression was much larger than that from linear amplifications and the larger ecDNA. The cytokine gene CXCL5 exemplified this phenomenon, showing substantial copy-number increase and upregulation when present on eccDNA. Functional validation in cell lines showed that CXCL5 eccDNA enhanced transcriptional output and immune cell recruitment function. The recurrence and overexpression of CRC-related genes on eccDNA indicate their selection in tumors, suggest eccDNA can serve as a novel mechanism for dynamically influencing gene expression and is capable of conferring cancer phenotypes to cells. Analysis of chromatin landscapes revealed that eccDNA preferentially forms at sites of open chromatin and active transcription, with architectural boundaries marked by CTCF protein. Clinically, patients with higher eccDNA levels showed poorer relapse-free survival. These findings suggest that circular DNA elements across the entire size spectrum participate in cancer evolution, positioning eccDNA as a potential therapeutic target and prognostic biomarker.

cancer biology↗

Single-Cell and WGCNA Integrative Analysis Reveal the Key Chondrocytes Niches and Pathogenic Genes in Intervertebral Disc Degeneration

Intervertebral disc degeneration (IDD) is a leading cause of low back pain, necessitating a comprehensive understanding of the molecular mechanisms driving disc degeneration to develop effective preventive and therapeutic strategies. Chondrocytes, as the predominant cellular constituents of the nucleus pulposus, are thought to play a pivotal role in the pathogenesis of IDD. In this study, we leveraged publicly available single-cell RNA sequencing (scRNA) data from the Gene Expression Omnibus (GEO) database for a comprehensive analysis. Employing unsupervised clustering methods, we successfully identified five distinct subtypes of chondrocytes and characterized two distinct terminal cell fates within the chondrocyte population. Through weighted gene co-expression network analysis (WGCNA), we identified RPL17, RPL13A, RPS18, and RPS24 as hub genes significantly associated with disc degeneration compared to control discs. Furthermore, our analysis of cell communication unveiled the activation of pro-inflammatory pathways in intervertebral disc degeneration. These findings shed light on the intricate complexity of chondrocyte involvement in the development of intervertebral disc degeneration and enhance our understanding of the role of chondrocyte niches within the nucleus pulposus during degenerative processes. Importantly, our study paves the way for potential targeted therapeutic approaches to address IDD.

bioinformatics↗

Granzyme B-based CAR T cells block metastasis by eliminating circulating tumor cells

Chimeric antigen receptor (CAR) T cells have limited efficacy against solid tumors due to the hostile microenvironment. Circulating tumor cells (CTCs) are essential to metastasis, which is the cause of most of cancer-related death. Here, we generated GrB-CAR T cells targeting membrane-bound HSP70 (mHSP70), a highly tumor-specific antigen detected in numerous cancers. GrB-CAR T cells exhibited potent cytotoxicity against a broad spectrum of cancer cell lines and stem-like cancer cells in vitro and effectively inhibited xenograft tumor growth in vivo. Importantly, GrB-CAR T cells markedly decreased the number of CTCs and, therefore, hindered cancer metastasis in spontaneous metastasis models with uncontrollable primary tumor growth, a scenario commonly encountered in clinical trials of CAR T therapies for solid tumors. Furthermore, despite the 100% homology between human and macaque HSP70 protein, the autotransplantation of macaque T cells expressing human GrB-CAR did not cause any obvious toxic effects. These results not only demonstrate GrB-CAR T cells as a safe and effective tactic with broad-spectrum anticancer activity, but also offer strong experimental evidence and proof-of-concept validation for CAR T cell-mediated metastasis inhibition by targeting CTCs.

immunology↗

Post-death Vesicles of Senescent Bone Marrow Mesenchymal Stromal Polyploids Promote Macrophage Aging and Breast Cancer

Potential systemic factors contributing to aging-associated breast cancer (BC) remain elusive. Here, we reveal that the polyploid giant cells (PGCs) that contain more than two sets of genomes prevailing in aging and cancerous tissues constitute 5-10% of healthy female bone marrow mesenchymal stromal cells (fBMSCs). The PGCs can repair DNA damage and stimulate neighboring cells for clonal expansion. However, dying PGCs in advanced-senescent fBMSCs can form "spikings" which are then separated into membraned mtDNA-containing vesicles (Senescent PGC-Spiking Bodies; SPSBs). SPSB-phagocytosed macrophages accelerate aging with diminished clearance on BC cells and protumor M2 polarization. SPSB-carried mitochondrial OXPHOS components are enriched in BC of elder patients and associated with poor prognosis. SPSB-incorporated breast epithelial cells develop aggressive characteristics and PGCs resembling the polyploid giant cancer cells (PGCCs) in clonogenic BC cells and cancer tissues. These findings highlight an aging BMSC-induced BC risk mediated by SPSB-induced macrophage dysfunction and epithelial cell precancerous transition. SIGNIFICANCEMechanisms underlying aging-associated cancer risk remain unelucidated. This work demonstrates that polyploid giant cells (PGCs) in bone marrow mesenchymal stromal cells (BMSCs) from healthy female bone marrow donors can boost neighboring cell proliferation for clonal expansion. However, the dying-senescent PGCs in the advanced-senescent fBMSCs can form "spikings" which are separated into mitochondrial DNA (mtDNA)-containing spiking bodies (senescent PGC-spiking bodies; SPSBs). The SPSBs promote macrophage aging and breast epithelial cell protumorigenic transition and form polyploid giant cancer cells. These results demonstrate a new form of ghost message from dying-senescent BMSCs, that may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/583755v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@f07b60org.highwire.dtl.DTLVardef@33ef98org.highwire.dtl.DTLVardef@1b720c8org.highwire.dtl.DTLVardef@1c9514d_HPS_FORMAT_FIGEXP M_FIG Xie et al demonstrate that the polyploid giant cells (PGCs) in the juvenile phase expansion of female bone marrow mesenchymal stromal cells (fBMSCs) can boost neighboring cell proliferation for clonal expansion. However, when fBMSCs enter to the advanced-senescent phase, the dying-senescent PGCs form "spikings" which are then separated into membraned vesicles termed Senescent PGC spiking bodies, SPSBs). The SPSBs carrying fragmented mitochondrial elements and OXPHOS proteins can be phagocytosed by macrophage and breast epithelial cells leading to macrophage aging and breast epithelial protumorigenic transition. The SPSBs are demonstrated to be a new form of post-cell death vesicle from aging BMSCs and may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk. C_FIG

cancer biology↗

Schlafen-11 and -9 are innate immune sensors for intracellular single-stranded DNA

Nucleic acids are major structures detected by the innate immune system. Although intracellular single-stranded DNA (ssDNA) is accumulated during pathogen infection or pathogenesis, it remains unclear whether and how intracellular ssDNA stimulates the immune system. We report that intracellular ssDNA triggers cytokine expression and cell death in a CGT motif-dependent manner. Through a genome-wide CRISPRLCas9 screen, we identified Schlafen-11 (SLFN11), which is essential for the response to endogenous and pathogen ssDNA. SLFN11 directly binds ssDNA containing CGT motifs and translocates to the cytoplasm upon ssDNA recognition. The mice deficient in SLFN9, the homologue of SLFN11, were resistant to CGT ssDNA-induced inflammation, acute hepatitis and septic shock. This study establishes CGT ssDNA and SLFN11/9 as a novel type of immunostimulatory nucleic acids and pattern recognition receptors, respectively. One-sentence summariessingle-stranded DNA inside cells can awaken Schlafens with a CGT motif to trigger cytokine expression and lytic cell death.

immunology↗

Focal adhesion protein vinculin inhibits Mef2c-driven sclerostin expression in osteocytes to promote bone formation in mice

The focal adhesion (FA) is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function. Here we show that expression of FA protein vinculin is dramatically reduced in osteocytes in patients with aging-related osteoporosis. Deleting vinculin using the mouse 10-kb Dmp1-Cre transgenic mice causes a severe osteopenia in both young and aged mice by impairing osteoblast function without affecting bone resorption. Vinculin loss impairs the anabolic response of skeleton to mechanical loading in mice. At the molecular level, vinculin knockdown increases, while vinculin overexpression decreases, sclerostin expression in osteocytes without impacting expression of Mef2c, a major transcriptional regulator of the Sost gene, which encodes sclerostin. Vinculin interacts with Mef2c and vinculin loss enhances Mef2c nuclear translocation and binding to the Sost enhancer ECR5 to promote sclerostin production in osteocytes. Deleting Sost expression reverses the osteopenic phenotypes caused by vinculin loss in mice. We demonstrate that estrogen is a major regulator of vinculin expression in osteocytes and that more importantly vinculin loss mediates estrogen deficiency induction of bone loss in mice. Thus, we demonstrate a novel mechanism through which vinculin inhibits the Mef2c-driven sclerostin expression in osteocytes to promote bone formation.

developmental biology↗

Simulation study of Cell Transmembrane Potential and Electroporation Induced by Time-Varying Magnetic Fields

In this work, an improved simulation model was proposed to assess the transmembrane potential (TMP) evolution on the cellular membrane exposed to time-varying magnetic fields (TMFs). Comparatively, we extended the research on TMP induced by TMF to the electroporation phenomenon by introducing the Smoluchowski function, thereby predicting the occurrence of electroporation. The simulation results based on our numerical model showed that with exposure to the sub-microsecond trapezoidal pulsed magnetic field (PMF), the pore density did not reach the conventional electroporation criterion (1014 m-2) even if the TMP exceeded the electroporation threshold ([~]1V); however, with the same energy import, it was easier for the nanosecond pulse to electroporate the membrane evidenced by higher pore density. Further, the capability of predicting the occurrence of electroporation was verified by extending our simulation model to compare experimental results. The comparative analysis showed that our simulation model has predictive and guiding significance for experimental studies and practical applications.

biophysics↗

Fracture healing is delayed in the absence of gasdermin signaling

Amino-terminal fragments from proteolytically cleaved gasdermins (GSDMs) form plasma membrane pores that enable the secretion of interleukin-1{beta} (IL-1{beta}) and IL-18. Excessive GSDM- mediated pore formation can compromise the integrity of the plasma membrane thereby causing the lytic inflammatory cell death, pyroptosis. We found that GSDMD and GSDME were the only GSDMs that were readily expressed in bone microenvironment. Therefore, we tested the hypothesis that GSDMD and GSDME are implicated in fracture healing owing to their role in the obligatory inflammatory response following injury. We found that bone callus volume and biomechanical properties of injured bones were significantly reduced in mice lacking either GSDM compared with wild-type (WT) mice, indicating that fracture healing was compromised in mutant mice. However, compound loss of GSDMD and GSDME did not exacerbate the outcomes, suggesting shared actions of both GSDMs in fracture healing. Mechanistically, bone injury induced IL-1{beta} and IL-18 secretion in vivo, a response that was mimicked in vitro by bone debris and ATP, which function as inflammatory danger signals. Importantly, the secretion of these cytokines was attenuated in conditions of GSDMD deficiency. Finally, deletion of IL-1 receptor reproduced the phenotype of Gsdmd or Gsdme deficient mice, implying that inflammatory responses induced by the GSDM-IL-1 axis promote bone healing after fracture.

immunology↗

Engineered neuron-targeting, placental mesenchymal stromal cell-derived extracellular vesicles for in utero treatment of myelomeningocele

This study investigated the feasibility and efficiency of neuron-targeting hybrid placental mesenchymal stromal cell-derived extracellular vesicles (PMSC-EVs), engineered by membrane fusion with Targeted Axonal Import (TAxI) peptide modified, TrkB agonist 7,8-DHF-loaded liposomes for treatment of myelomeningocele (MMC) via intra-amniotic cavity administration. The prepared TAxI modified liposomes with 7,8-DHF were used to fuse with PMSC-EVs. Different fusion approaches were investigated and freeze-thaw-extrude method was found to be the optimal. The engineered PMSC-EVs had a uniform particle size and efficiently loaded 7,8-DHF. It also had typical markers of native EVs. Freeze-thaw-extrude process did not change the release profile of 7,8-DHF from engineered EVs compared to TAxI modified, 7,8-DHF loaded liposomes. The engineered EVs could elicit TrkB phosphorylation depending on the incorporation of 7,8-DHF while native EVs did not. The engineered EVs increased neurite outgrowth of apoptotic cortical neurons induced by staurosporine, suggesting that they exhibited neuroprotective function. In a rodent model of MMC, neuron-targeting, engineered EVs became an active targeting delivery system to MMC defect sites. Pups treated with engineered EVs had the lowest density of apoptotic cells and displayed a therapeutic outcome. The study suggests the potential use of engineered hybrid, active neuron-targeting EVs for the in utero treatment of MMC.

bioengineering↗

SmProt: a reliable repository with comprehensive annotation of small proteins identified from ribosome profiling

Small proteins specifically refer to proteins consisting of less than 100 amino acids translated from small open reading frames (sORFs), which were usually missed in previous genome annotation. The significance of small proteins has been revealed in current years, along with the discovery of their diverse functions. However, systematic annotation of small proteins is still insufficient. SmProt was specially developed to provide valuable information on small proteins for scientific community. Here we present the update of SmProt, which emphasizes reliability of translated sORFs, genetic variants in translated sORFs, disease-specific sORFs translation events or sequences, and significantly increased data volume. More components such as non-AUG translation initiation, function, and new sources are also included. SmProt incorporated 638,958 unique small proteins curated from 3,165,229 primary records, which were computationally predicted from 419 ribosome profiling (Ribo-seq) datasets and collected from the literature and other sources originating from 370 cell lines or tissues in 8 species (Homo sapiens, Mus musculus, Rattus norvegicus, Drosophila melanogaster, Danio rerio, Saccharomyces cerevisiae, Caenorhabditis elegans, and Escherichia coli). In addition, small protein families identified from human microbiomes were collected. All datasets in SmProt are free to access, and available for browse, search, and bulk downloads at http://bigdata.ibp.ac.cn/SmProt/.

bioinformatics↗

Functionalized extracellular matrix scaffolds loaded with endothelial progenitor cells promote neovascularization and diabetic wound healing

Diabetic ischemic wound treatment remains a critical clinical challenge. Strategies that enhance angiogenesis and improve ischemic pathology may promote the healing of poor wounds, particularly diabetic wounds in highly ischemic condition. We previously identified a cyclic peptide LXW7 that specifically binds to integrin v{beta}3 on endothelial progenitor cells (EPCs) and endothelial cells (ECs), activates VEGF receptors, and promotes EC growth and maturation. In this study, we designed and synthesized a pro-angiogenic molecule LXW7-DS-SILY by conjugating LXW7 to a collagen-binding proteoglycan mimetic DS-SILY and further employed this novel bifunctional ligand to functionalize extracellular matrix (ECM) scaffolds, promote neovascularization and accelerate ischemic wound healing. We established a Zucker Diabetic Fatty (ZDF) rat ischemic skin flap model and found the wounds treated by LXW7-DS-SILY-functionalized ECM scaffolds, with or without EPCs, significantly improved wound healing, enhanced neovascularization and modulated collagen fibrillogenesis. These functionalized ECM scaffolds also significantly promoted EPC attachment, growth and survival in the ischemic environment. Altogether, this study provides a promising novel treatment to accelerate diabetic ischemic wound healing, thereby reducing limb amputation and mortality of diabetic patients.

bioengineering↗

iTRAQ-Based Proteomic Profiling of PLC-Mediated Expression of 20E-Induced Protein in Apolygus lucorum (Meyer-Dür)

The polyphagous pest Apolygus lucorum has become the dominant insect in Bacillus thuringiensis (Bt) cotton fields. The hormone 20-hydroxyecdysone (20E) regulates multiple events in insect development and physiology. 20E responses are controlled by pathways triggered by phospholipase C (PLC)-associated proteins. However, 20E-modulated genes whose expression is affected by PLC remain unknown. Here, isobaric tag for relative and absolute quantitation (iTRAQ) and immunoblot were carried out for comparing differentially expressed proteins (DEPs) in A. lucorum in response to 20E and the PLC inhibitor U73122, respectively. Totally 1624 DEPs were, respectively, found in the 20E/control, U73122/control, and 20E+U73122/control groups. Venn diagram analysis further revealed 8 DEPs that were shared among the three groups. Immunoblot validated these findings, which corroborated and highlighted the reliability of proteomics. KEGG enrichment analysis showed that the DEPs were included in diverse signaling pathways. The largest portion of DEPs among the three groups were categorized in metabolic pathways. In addition, DEPs among the three groups were also found to regulate the Ras-MAPK and PI3K-AKT pathways. This is the first time that iTRAQ was carried out to assess proteome alteration in A. lucorum nymphs in response to 20E and a PLC inhibitor. These findings provide novel insights into protein expression in A. lucorum in response to 20E, and a more comprehensive understanding of the function of PLC in 20E signal transduction.

biochemistry↗