Biology subjects

Mo, J.

Publications and source records attributed to Mo, J..

36 records · Page 2Linked to original sources

bioRxiv2024

An antibiotic that mediates immune destruction of senescent cancer cells

Drugs that eliminate senescent cells, senolytics, can be powerful when combined with pro-senescence cancer therapies. Using a CRISPR/Cas9-based genetic screen, we identify here SLC25A23 as a vulnerability of senescent cancer cells. Suppressing SLC25A23 disrupts cellular calcium homeostasis, impairs oxidative phosphorylation and interferes with redox signaling, leading to death of senescent cells. These effects can be replicated by salinomycin, a cation ionophore antibiotic. Salinomycin prompts a PANoptosis-like cell death in senescent cells, including apoptosis and two forms of immunogenic cell death: necroptosis and pyroptosis. Notably, we observed that salinomycin treatment or SLC25A23 suppression elevates reactive oxygen species, upregulating death receptor 5 via JNK pathway activation. We show that a combination of a DR5 agonistic antibody and salinomycin is a robust senolytic cocktail. We provide evidence that this drug combination provokes a potent NK and CD8+ T cell mediated immune destruction of senescent cancer cells, mediated by the pyroptotic cytokine IL18. SignificanceThe efficacy of multiple cancer drugs is limited by the induction of senescence, which enables cancer cells to evade cell death. We uncover here a new selective vulnerability of senescent cancer cells and we show that this vulnerability can be targeted with a commonly-used antibiotic. We show that a combination of senescence-inducing therapy, combined with this antibiotic causes a highly immunogenic cell death phenotype that further stimulates potent immune destruction of senescent cancer cells.

cancer biology↗

bioRxiv2024

Mycn regulates vascular development through PI3K signaling pathway in zebrafish

Mycn, a MYC gene family member, is implicated in both carcinogenesis through amplification and Feingold syndrome through its deficiency. Previous studies have indicated that increased Mycn expression enhances vascularization in human neuroblastomas, yet its precise role in vascular development remains elusive. In this study, we utilized single-cell RNA-seq and live imaging analyses to confirm that mycn is expressed during zebrafish vasculogenesis. We investigated vascular development in zebrafish using a genetically engineered mycn mutation. Our findings reveal that mycn-deficient zebrafish exhibit reduced intersegmental vessels and malformed subintestinal vessels, primarily due to decreased cell proliferation in vascular cells. Importantly, we discovered that activation of PI3K signaling significantly ameliorates these vascular abnormalities.

developmental biology↗

bioRxiv2024

Wireless, Multimodal Monitoring of Organ Health Using 3D-Printed, Barbed, Bioresorbable Stretchable Microneedle Sensor Arrays

Comprehensive and continuous assessment of organ physiology and biochemistry, beyond the capabilities of conventional monitoring tools, can enable timely interventions for intraoperative complications like organ ischemia and nerve injuries and postoperative conditions such as organ dysfunction and transplant rejection. Here, we report a wireless implant with a 3D-printed, barbed, bioresorbable stretchable microneedle sensor array that offers multimodal monitoring of organ metabolism, oxygenation, and electrophysiology as well as spatiotemporal mapping of biomarkers across different organ regions. The development of a deformation-coupled 3D-printing technique enables 3D-programmable manufacturing of microneedles with monolithic backward-facing barbs, offering conformal yet robust 3D probing of organs with dynamic mechanics. Electrochemical functionalization of microneedle tips serves as a universal approach for localized sensing of physiological and biochemical parameters, enabling concurrent monitoring of up to 36 parameters (glucose, uric acid, oxygen, etc.) and spatiotemporal mapping of up to 32 sites. An electrically programmable self-destruction mechanism based on crevice corrosion and bioresorption eliminates the need for traumatic retrieval of microneedles. Demonstrations in clinically relevant complications like kidney ischemia and gut disorders in animal models highlight the broad applications of this device in intra- and postoperative monitoring.

bioengineering↗

bioRxiv2024

Genetic insertion of mouse Myxovirus-resistance gene 1 increases innate resistance against both high and low pathogenic avian influenza virus by significantly decreasing replication in chicken DF1 cell line

Avian influenza virus (AIV) is a constant threat to animal health with recent global outbreaks resulting in the death of hundreds of millions of birds with spillover into mammals. Myxovirus-resistance (Mx) proteins are key mediators of the antiviral response that block virus replication. Mouse (Mu) Mx (Mx1) is a strong antiviral protein that interacts with the viral nucleoprotein to inhibit polymerase function. The ability of avian Mx1 to inhibit AIV is unclear. In these studies, Mu Mx1 was stably introduced into chicken DF1 cells to enhance the immune response against AIV. Following infection, titers of AIV were significantly decreased in cells expressing Mu Mx1. In addition, considerably less cytopathic effect (CPE) and matrix protein staining was observed in gene-edited cells expressing Mu Mx1, suggesting Mu Mx1 is broadly effective against multiple AIV subtypes. This work provides foundational studies for use of gene-editing to enhance innate disease resistance against AIV.

immunology↗

bioRxiv2024

Morphologic characterization and cytokine response of chicken bone-marrow derived dendritic cells to infection with high and low pathogenic avian influenza virus

Dendritic cells (DCs) are professional antigen-presenting cells, which are key components of the immune system and involved in the early immune response. DCs are specialized in capturing, processing, and presenting antigens to facilitate immune interactions. Chickens infected with avian influenza virus (AIV) demonstrate a wide range of clinical symptoms, based on pathogenicity of the virus. Low pathogenic avian influenza (LPAI) viruses typically induce mild clinical signs, whereas high pathogenic avian influenza (HPAI) induce more severe disease, which can lead to death within days. For this study, chicken bone marrow-derived DC (ckBM-DC)s were produced and infected with high and low pathogenic avian influenza viruses of H5N2 or H7N3 subtypes to characterize innate immune responses, study effect on cell morphology, and evaluate virus replication. A strong proinflammatory response, including chicken interleukin-1{beta}, and stimulation of the interferon response pathway were observed at 8 hours post infection. Microscopically, the DCs underwent morphological changes from classic elongated dendrites to a more general rounded shape that eventually lead to cell death with the presence of scattered cellular debris. Differences in onset of morphologic changes were observed between H5 and H7 subtypes. Increases in viral titers demonstrated that both HPAI and LPAI are capable of infecting and replicating in DCs. The elevated expression of infected DCs may be indicative with a dysregulation of the immune response typically seen with HPAI infections.

immunology↗

bioRxiv2023

Unleashing the Power of NR4A1 Degradation as a Novel Strategy for Cancer Immunotherapy

An effective cancer therapy requires both killing cancer cells and targeting tumor-promoting pathways or cell populations within the tumor microenvironment (TME). We purposely search for molecules that are critical for multiple tumor-promoting cell types and identified nuclear receptor subfamily 4 group A member 1 (NR4A1) as one such molecule. NR4A1 has been shown to promote the aggressiveness of cancer cells and maintain the immune suppressive TME. Using genetic and pharmacological approaches, we establish NR4A1 as a valid therapeutic target for cancer therapy. Importantly, we have developed the first-of-its kind proteolysis-targeting chimera (PROTAC, named NR-V04) against NR4A1. NR-V04 effectively degrades NR4A1 within hours of treatment in vitro and sustains for at least 4 days in vivo, exhibiting long-lasting NR4A1-degradation in tumors and an excellent safety profile. NR-V04 leads to robust tumor inhibition and sometimes eradication of established melanoma tumors. At the mechanistic level, we have identified an unexpected novel mechanism via significant induction of tumor-infiltrating (TI) B cells as well as an inhibition of monocytic myeloid derived suppressor cells (m-MDSC), two clinically relevant immune cell populations in human melanomas. Overall, NR-V04-mediated NR4A1 degradation holds promise for enhancing anti- cancer immune responses and offers a new avenue for treating various types of cancer.

cancer biology↗

bioRxiv2023

Contrasting roles of different mismatch repair proteins in basal-like breast cancer

The mismatch repair (MMR) pathway is known as a tumor suppressive pathway and genes involved in MMR are commonly mutated in hereditary colorectal or other cancer types. However, the function of MMR genes/proteins in breast cancer progression and metastasis are largely undefined. We found that MSH2, but not MLH1, is highly enriched in basal-like breast cancer (BLBC) and that its protein expression is inversely correlated with overall survival time (OS). MSH2 expression is frequently elevated due to genomic amplification or gain-of-expression in BLBC, which results in increased MSH2 protein to pair with MSH6 (collectively referred to as MutS). Genetic deletion of MSH2 or MLH1 results in a contrasting phenotype in metastasis, with MSH2-deletion leading to reduced metastasis and MLH1-deletion to enhanced liver or lung metastasis. Mechanistically, MSH2 - but not MLH1 - binds to the promoter region of interferon receptor 1 (IFNAR1) and suppresses its expression in BLBC. Deletion of MSH2 initiates a chain of immune reactions via the upregulation of IFNAR1 expression and the activation of type 1 interferon signaling, which explains a highly immune active tumor microenvironment in tumors with MSH2-deficiency. Our study supports the contrasting functions of MSH2 and MLH1 in BLBC progression and metastasis due to the differential regulation of IFNAR1 expression, which challenges the paradigm of the MMR pathway as a universal tumor suppressive mechanism.

cancer biology↗

bioRxiv2023

Ligament injury in adult zebrafish triggers ECM remodeling and cell dedifferentiation for scar-free regeneration

After traumatic injury, healing of mammalian ligaments is typically associated with fibrotic scarring as opposed to scar-free regeneration. In contrast, here we show that the ligament supporting the jaw joint of adult zebrafish is capable of rapid and complete scar-free healing. Following surgical transection of the jaw joint ligament, we observe breakdown of ligament tissue adjacent to the cut sites, expansion of mesenchymal tissue within the wound site, and then remodeling of extracellular matrix (ECM) to a normal ligament morphology. Lineage tracing of mature ligamentocytes following transection shows that they dedifferentiate, undergo cell cycle re-entry, and contribute to the regenerated ligament. Single-cell RNA sequencing of the regenerating ligament reveals dynamic expression of ECM genes in neural-crest-derived mesenchymal cells, as well as diverse immune cells expressing the endopeptidase-encoding gene legumain. Analysis of legumain mutant zebrafish shows a requirement for early ECM remodeling and efficient ligament regeneration. Our study establishes a new model of adult scar-free ligament regeneration and highlights roles of immune-mesenchyme cross-talk in ECM remodeling that initiates regeneration. HighlightsO_LIRapid regeneration of the jaw joint ligament in adult zebrafish C_LIO_LIDedifferentiation of mature ligamentocytes contributes to regeneration C_LIO_LIscRNAseq reveals dynamic ECM remodeling and immune activation during regeneration C_LIO_LIRequirement of Legumain for ECM remodeling and ligament healing C_LI

molecular biology↗

bioRxiv2021

Does the ratio of β-1,4-glucosidase (BG) to β-1,4-N-acetylglucosaminidase (NAG) indicate the relative resource allocation of soil microbes to C and N acquisition?

The ratio of {beta}-1,4-glucosidase (BG) to {beta}-1,4-N-acetylglucosaminidase (NAG) activity (BG:NAG ratio) is often used as an indicator of the relative resource allocation of soil microbes to C acquisition compared with N. An increasing number of recent studies have used this index to assess the nutrient status of microbes. However, the validity of this index for assessing the nutrient status of microbes is not well tested. In this study, we collected published data and tested that validity by investigating whether N fertilization elevated the BG:NAG ratio, assuming that microbes reduce their allocation to the N-acquiring enzyme (NAG) under N-enriched conditions. Of the data points, 54% (82/151) did not support the hypothesis because those studies showed lower BG:NAG ratios in N-enriched soils than under ambient conditions, especially when the ambient BG:NAG ratio was higher than 2.0 (77%, 59/77). This suggests that the BG:NAG ratio does not always indicate the microbial status for C or N limitation. Rather, we hypothesized that the decomposition stage explained the variation in BG:NAG because N addition accelerates decomposition, and the BG:NAG ratio is lower at later stages of decomposition due to the dominance of NAG-targeting C (chitin or peptidoglycan). A negative correlation of BG:NAG ratio with polyphenol oxidase activity, which increases with decomposition, supported our hypothesis.

ecology↗

bioRxiv2020

Srsf3 mediates alternative RNA splicing downstream of PDGFRα signaling

Signaling through the platelet-derived growth factor receptor alpha (PDGFR) is critical for mammalian craniofacial development, though the mechanisms by which the activity of downstream intracellular effectors is regulated to mediate gene expression changes have not been defined. We find that the RNA-binding protein Srsf3 is phosphorylated at Akt consensus sites downstream of PI3K-mediated PDGFR signaling in palatal mesenchyme cells, leading to its nuclear translocation. We further demonstrate that ablation of Srsf3 in the neural crest lineage leads to facial clefting due to defective cranial neural crest cell specification and survival. Finally, we show that Srsf3 regulates the alternative RNA splicing of transcripts encoding protein kinases in the facial process mesenchyme to negatively regulate PDGFR signaling. Collectively, our findings reveal that PI3K/Akt-mediated PDGFR signaling primarily modulates gene expression through alternative RNA splicing in the facial mesenchyme and identify Srsf3 as a critical regulator of craniofacial development.

developmental biology↗

bioRxiv2020

Zinc Sulfide-Based Hybrid Exosome-Coated Autophagy-Mediated H2S-sensitized PDT/chemotherapeutic Synergistic Nanoplatform for Targeted Treatment of Glioblastoma Stem-Like Cells in Orthotopic Mouse Glioblastoma Model

Core-hybrid shell hydroxychloroquine (HCQ) loaded zinc sulfide (ZnS) nanoparticles were synthesized, characterized and evaluated for the treatment of glioblastoma cells in vitro and in vivo. These particles, denoted as HCQ@ZnS@exo@iRGD, consist of hollow ZnS nanoparticles loading with the autophagic inhibitor of hydroxychloroquine and covered by a hybrid shell containing exosomes (exo) and phosphatidylserine derived pH- and redox-responsive pegylated iRGD peptide, a gliomablastoma-homing and penetrating peptide. The hybrid exosomes enable HCQ@ZnS with good permeability across the blood-brain barrier and targeting ability to glioblastoma cells in orthotopic mouse glioblastoma model. ZnS acts as a photosensitizer for reactive oxygen species (ROS) production to inflict damage to organelles within glioblastoma cells. Hydroxychloroquine inhibits autophagic flux, which can subsequently lead to the accumulation of impaired organelles caused by the ROS. As a result, substantial selective damage to glioblastoma cells was realized owing to the hybrid exosomes guiding the anti-tumour effects of hydroxychloroquine and ZnS under light irradiation. The results provide evidence for the utility of HCQ@ZnS@exo@iRGD as a therapeutic strategy for glioblastoma.

pharmacology and toxicology↗

bioRxiv2020

Pdgfra and Pdgfrb genetically interact in the murine neural crest cell lineage to regulate migration and proliferation

Cranial neural crest cells (cNCCs) are migratory, multipotent cells that originate from the forebrain to the hindbrain and eventually give rise to the bone and cartilage of the frontonasal skeleton, among other derivatives. Signaling through the two members of the platelet-derived growth factor receptor (PDGFR) family of receptor tyrosine kinases, alpha and beta, plays critical roles in the cNCC lineage to regulate craniofacial development during murine embryogenesis. Further, the PDGFRs have been shown to genetically interact during murine craniofacial development at mid-to-late gestation. Here, we examined the effect of ablating both Pdgfra and Pdgfrb in the murine NCC lineage on earlier craniofacial development and determined the cellular mechanisms by which the observed phenotypes arose. Our results confirm a genetic interaction between the two receptors in this lineage, as phenotypes observed in an allelic series of mutant embryos often worsened with the addition of conditional alleles. The defects observed here were shown to stem from reduced cNCC stream size and aberrant cNCC directional migration, as well as decreased proliferation of the facial mesenchyme upon combined decreases in PDGFR and PDGFR{beta} signaling. Importantly, we found that PDGFR plays a predominant role in cNCC migration whereas PDGFR{beta} primarily contributes to proliferation of the facial mesenchyme. Our findings provide insight into the distinct mechanisms by which PDGFR and PDGFR{beta} signaling regulate cNCC activity and subsequent craniofacial development in the mouse embryo.

developmental biology↗

bioRxiv2020

Generation of multi-transgenic pigs using PiggyBac transposons co-expressing pectinase, xylanase, cellulase?β-1.3-1.4-glucanase and phytase

The current challenges facing the pork industry are to maximize feed efficiency and minimize fecal emissions. Unlike ruminants, pigs lack a number of digestive enzymes like pectinase, xylanase, cellulase, {beta}-1.3-1.4-glucanase and phytase to hydrolyze the cell walls of grains to release endocellular nutrients into their digestive tracts. Herein, we synthesized multiple cellulase and pectinase genes derived from lower organisms and then codon optimized these genes to be expressed in pigs. These genes were then cloned into our previously optimized XynB (xylanase)- EsAPPA (phytase) bicistronic construct. We then successfully generated transgenic pigs that expressed four enzymes (Pg7fn (pectinase), XynB (xylanase), EsAPPA (phytase) and TeEGI (cellulase and {beta}-glucanase)) using somatic cell cloning. Expression of these genes was parotid gland specific. Enzymatic assays using the saliva of these founders demonstrated high levels of phytase (2.0~3.4 U/mL) and xylanase (0.25~0.42 U/mL) activity, but low levels of pectinase (0.06~0.08 U/mL) activity. These multi-transgenic pigs are expected to contribute to enhance feed utilization and reduce environmental impact.

genetics↗

bioRxiv2019

Diagnostic value of galactomannan in bronchoalveolar lavage fluid for chronic respiratory disease with pulmonary aspergillosis

ObjectiveTo explore the diagnostic value of the bronchoalveolar lavage fluid galactomannan (BALF GM) test for chronic respiratory disease with pulmonary aspergillosis, and establish the optimal cut-off value.\n\nMethodsA total of 180 chronic respiratory disease patients seen at the Respiratory Medicine Department of Peking University Shenzhen Hospital from September 2017 to September 2018 were analyzed. According to the diagnostic criteria, we divided the patients into the case group (n = 70, comprising 5, 20, and 45 proven, probable, and possible cases, respectively) and the control group (n = 110). Bronchoalveolar lavage fluid was collected, and the BALF GM test results were analyzed.\n\nResultsA non-parametric rank-sum test showed that the mean rank of the case group was 140.80, which was higher than that of the control group (58.49). The Z-value was 10.335 (P = 0.000), indicating that the general distribution of BALF GM differed between the two groups. A BALF GM cut-off value of 0.485 showed the highest diagnostic efficacy for pulmonary aspergillosis. The sensitivity, specificity, positive predictive value, and negative predictive value were 92.9%, 100%, 92.8%, and 100%, respectively. As the cut-off value increased, the specificity and sensitivity of the BALF GM test increased and decreased, respectively.\n\nConclusionsThe BALF GM test can be used confirm the diagnosis of patients with pulmonary aspergillosis and chronic respiratory disease. The optimum BALF GM cut-off value was 0.485. Antifungal therapy is important for treating pulmonary aspergillus infection in patients with chronic respiratory disease.

microbiology↗

bioRxiv2019

CRISPR/Cas9-mediated integration of large transgene into pig potential safe harbor

Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (Cas9) is a precise genome manipulating tool which can produce targeted gene mutations in various cells and organisms. Although CRISPR/Cas9 can efficiently generate gene knock-out, the gene knock-in efficiency mediated by homology-directed repair (HDR) remains low, especially for large fragment integration. In this study, we established an efficient method for CRISPR/Cas9-mediated integration of large transgene cassette carrying salivary gland-expressing multiple digestion enzymes ({approx} 20 kbp) in CEP112 locus in pig fetal fibroblasts. Our results showed that using homologous donor with a short left arm and a long right arm yielded the best CRISPR/Cas9-mediated knock-in efficiency, and the targeting efficiency in potential safe harbor CEP112 locus are higher than ROSA26 locus. The CEP112 knock-in cell lines were used as nuclear donors for somatic cell nuclear transfer to create genetically modified pigs. We found that knock-in pig (705) successfully expressed three microbial enzymes ({beta}-glucanase, xylanase, and phytase) in salivary gland, suggesting potential safe harbor CEP112 locus supports exogenous genes expression by a tissue-specific promoter. In summary, we successfully targeted CEP112 locus using our optimal homology arm system for precise modification of pigs, and established a modified pig model for foreign digestion enzyme expression in saliva.

bioengineering↗

bioRxiv2019

The nervous system is the major target for Gold nanoparticle-based therapy: Evidence from RNA sequencing data of C. elegans

The increasing use of gold nanoparticles (NPs) raises concerns about the potential effect of gold NPs exposure on human health. Therefore, gold NPs exposure is hard to evaluate at the organ level with current measurement technology. The bio-distribution assay showed that intestine was the organ with most gold NPs accumulated in C. elegans. However, our data indicated that 62.8% of the significant altered genes were function in the nervous system using tissue enrichment analysis. Notably, developmental stage analysis has demonstrated that NP exposure interfered with the development of animals. Furthermore, the transcription factors DAF-16 was regulating the oxidative stress genes induced by gold NPs. Therefore, we proposed the localization of the oxidative stress genes in the neuron cells and how their expression affect neuron communication. Our results demonstrate that the gold NPs-induced oxidative stress affects the nervous system via physical damage to the neurons and disruption of cell-to-cell communication. Future toxicology research on gold NPs should focus on neurons. O_FIG O_LINKSMALLFIG WIDTH=120 HEIGHT=200 SRC="FIGDIR/small/699785v2_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@19effeorg.highwire.dtl.DTLVardef@db10d9org.highwire.dtl.DTLVardef@2f4736org.highwire.dtl.DTLVardef@1ec2a52_HPS_FORMAT_FIGEXP M_FIG Graphical abstract C_FIG

neuroscience↗

bioRxiv2019

Is microbial activity in tropical forests limited by phosphorus availability? Evidence from a tropical forest in China

The prevailing paradigm for soil microbial activity in tropical forests is that microbial activity is limited by phosphorus (P) availability. Thus, exogenous P addition should increase rates of organic matter decomposition. Studies have also confirmed that soil respiration is accelerated when P is added experimentally. However, we hypothesize that the increased rates of soil microbial respiration could be due to the release of organic material from the surface of soil minerals when P is added, because P is more successful at binding to soil particles than organic compounds. In this study, we demonstrate that P addition to soil is associated with significantly higher dissolved organic carbon (DOC) content in a tropical evergreen forest in southern China. Our results indicate that P fertilization stimulated soil respiration but suppressed litter decomposition. Results from a second sorption experiment revealed that the recovery ratio of added DOC in the soil of a plot fertilized with P for 9 years was larger than the ratio in the soil of a non-fertilized plot, although the difference was small. We also conducted a literature review on the effects of P fertilization on the decomposition rates of litter and soil organic matter at our study site. Previous studies have consistently reported that P addition led to higher response ratios of soil microbial respiration than litter decomposition. Therefore, experiments based on P addition cannot be used to test whether microbial activity is P-limited in tropical forest soils, because organic carbon desorption occurs when P is added. Our findings suggest that the prevailing paradigm on the relationship between P and microbial activity in tropical forest soils should be re-evaluated.

ecology↗

bioRxiv2018

Generation of a novel growth-enhanced and reduced environmental impact transgenic pig strain

In pig production, insufficient feed digestion causes excessive nutrients such as phosphorus and nitrogen, which are then released to the environment. To address the issue of environmental emissions, we have established transgenic pigs harboring a single-copy quad-cistronic transgene and simultaneously expressing three microbial enzymes, {beta}-glucanase, xylanase, and phytase in the salivary glands. All the transgenic enzymes were successfully expressed, and the digestion of non-starch polysaccharides (NSPs) and phytate in the feedstuff was enhanced. Fecal nitrogen and phosphate outputs were reduced by 23%-46%, and growth rate improved by 23.4% (gilts) and 24.4% (boars) when the pigs were fed on a corn and soybean-based diet and high-NSP diet. The transgenic pigs showed a 11.5%- 14.5% improvement in feed conversion rate compared to the age-matched wild-type littermates. These findings indicate that transgenic pigs are promising resources for improving feed efficiency and reducing nutrient emissions to the environment.

biochemistry↗