Biology subjects

Ju, J.

Publications and source records attributed to Ju, J..

At least 19 recordsLinked to original sources

bioRxiv2026

Development of gemcitabine-modified miR-15a as a novel, multimodal treatment strategy to overcome 5-FU and oxaliplatin resistance in colorectal cancer

BackgroundResistance to 5-fluorouracil (5-FU)-based chemotherapy is a major clinical obstacle in colorectal cancer (CRC), highlighting the urgent need to overcome established resistance mechanisms. MicroRNA-based therapeutics have emerged as compelling candidates in this context, given their inherently pleiotropic mode of action; however, their clinical translation remains hindered by poor stability and suboptimal delivery. MethodsTo address these limitations, Gem-miR-15a, a unique gemcitabine-modified tumor-suppressor microRNA-15a was designed to synergistically integrate the tumor-suppressive activity of miR-15a with the chemotherapeutic potency of gemcitabine into a single molecular entity. Therapeutic efficacy of Gem-miR-15a was evaluated across a spectrum of preclinical models, including parental and drug-resistant CRC cell lines, 3D tumor spheroids, patient-derived organoids and in vivo metastatic models. Cell viability, apoptosis and cell cycle analyses were performed, along with RNA sequencing and protein validation. Statistical analyses were conducted using Students t-test or two-way ANOVA with mixed effects, and data were presented as mean {+/-} SD. ResultsGem-miR-15a exhibited potent anti-proliferative activity with IC50 values in the low nanomolar range, achieving [~]100-5000-fold greater potency relative to 5-FU and oxaliplatin. Importantly, it retained efficacy in both 5-FU- and oxaliplatin-resistant CRC models, effectively overcoming acquired chemoresistance. Mechanistically, Gem-miR-15a induced S-phase cell cycle arrest, eliminated the G2-phase cell population, and triggered apoptosis, accompanied by suppression of key oncogenic targets including WEE1, CHK1, YAP1 and BMI1. RNA-seq analysis further demonstrated modulation of pathways such as p53 signaling and reversal of resistance-associated gene expression, that were corroborated at the protein level. In vivo, Gem-miR-15a significantly reduced tumor growth at a dose [~]12-fold lower than gemcitabine, with no observable toxicity. ConclusionGem-miR-15a represents a potent, multi-targeted therapeutic strategy capable of overcoming chemoresistance in CRC. Its enhanced stability, effective delivery and robust efficacy across resistant models and a favorable safety profile highlight its strong potential for clinical translation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/720825v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@c20034org.highwire.dtl.DTLVardef@9b8478org.highwire.dtl.DTLVardef@161f1dorg.highwire.dtl.DTLVardef@54d826_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2026

Developing a Multimodal miR-15a Mimic to Overcome PARP Inhibitor Resistance in Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is characterized by high relapse rates and the development of drug resistance, driven by adaptive DNA repair and survival pathways. Here, we develop a multimodal, chemically engineered miRNA therapeutic, MTX-5-FU-Gem-miR-15a, that integrates tumor-suppressive miR-15a activity with chemotherapeutic modifications and tumor-targeting capability. This modified miRNA exhibits potent nanomolar activity across diverse EOC models, including PARP inhibitor-resistant cells, without requiring delivery vehicles. Mechanistically, MTX-5-FU-Gem-miR-15a induces replication stress while suppressing G2/M checkpoint regulators (WEE1 and CHK1), resulting in genomic instability and apoptotic cell death. Transcriptomic and protein-level analyses revealed coordinated suppression of resistance-associated and oncogenic signaling pathways, alongside activation of DNA damage coupled with checkpoint abrogation and potential innate immune response. MTX-5-FU-Gem-miR-15a also demonstrates strong synergy with olaparib and robust antitumor efficacy in vivo. These findings establish a multimodal miRNA-based therapeutic strategy that targets replication stress and checkpoint dependency to overcome PARPi resistance in ovarian cancer.

cancer biology↗

bioRxiv2025

Copper-Free Click Chemistry Enables High-Fidelity Engineering of Mitochondria Targeted Brain-Derived Exosomes

Mitochondrial dysfunction is a hallmark of neurodegenerative and neuroinflammatory disorders, including hypertension and cardiovascular disease, yet strategies for safe and precise mitochondrial-targeted delivery remain limited. Here, we establish strain-promoted azide-alkyne cycloaddition (SPAAC) as a biocompatible, high-fidelity chemical platform for engineering mitochondria-targeted brain-derived exosomes (BR-EVs). Copper-free click conjugation of a mitochondrial-targeting ligand (e.g. Cy5-DBCO) under mild aqueous conditions preserved vesicle morphology (30-150 nm core; 120-200 nm hydrodynamic), proteomic composition, and uptake dynamics. Time-course imaging and fluorescence recovery after photobleaching (FRAP) revealed unaltered endocytic kinetics, >75 % mitochondrial colocalization, and intact organelle architecture. In vivo neuroinflammation and biodistribution analyses demonstrated immunological neutrality, strong central nervous system retention, and minimal peripheral dispersion following intracerebroventricular administration. Proteomic profiling of unlabeled Sprague-Dawley (SD) and hypertensive Dahl salt-sensitive (DSS) BR-EVs uncovered hypertension-driven enrichment of oxidative and complement pathways correlating with mitochondrial fragmentation and reactive oxygen species generation in neuronal cultures. These findings establish SPAAC-mediated ligand conjugation as a biocompatible and chemically precise approach for generating mitochondria-targeted exosomes that preserve exosomal identity, biodistribution, and signaling fidelity--advancing a foundational platform for organelle-specific delivery and mechanistic imaging in the central nervous system.

neuroscience↗

bioRxiv2025

A Reversible Mitochondrial ROS Probe for Monitoring Mitophagy Dynamics: Development and Application of MitoFlare

Mitochondrial dysfunction and defective mitophagy are defining features of numerous neurodegenerative and metabolic disorders, yet existing tools provide limited ability to quantify mitophagy dynamics in real time within living, post-mitotic cells. Here we present MitoFlare, a mitochondria-targeted, reversible mtROS-responsive fluorogenic probe that enables continuous, non-genetic visualization of mitochondrial oxidative activation and turnover. MitoFlare incorporates dual TEMPO nitroxide quenchers into a long-wavelength rhodamine scaffold, producing >95% basal quenching and rapid, fully reversible fluorescence activation in response to mitochondrial superoxide, hydroxyl radicals, lipid-derived peroxyl species, and peroxynitrite. When combined with LysoTracker Green, MitoFlare forms a dual-probe imaging platform that resolves the entire mitophagy cascade with high spatial and temporal fidelity in intact PC12 neuronal cells. Using this platform, we established a quantitative framework comprising three mechanistically distinct metrics: (i) a proximity index that reports early mitochondrial engagement with lysosomes, (ii) Manders M1 coefficient that captures mid-stage mitochondria-lysosome fusion and mitophagosome formation, and (iii) a quenching/swelling index that resolves terminal lysosomal degradation. Nutrient deprivation induced a complete, temporally ordered mitophagy program, including mtROS priming, Parkin-OPTN-associated fusion, and efficient acidification-dependent cargo degradation. In contrast, inhibition of v-ATPase with bafilomycin A1 arrested mitophagy at the fusion stage, resulting in persistent redox-active mitochondrial cargo that failed to undergo lysosomal digestion. Importantly, MitoFlares reversible redox chemistry uniquely revealed accumulation of undegraded, oxidatively active mitochondrial remnants within non-acidified vesicles--pathological intermediates that are undetectable using irreversible ROS dyes or genetically encoded reporters. These findings demonstrate that mitophagy proceeds through discrete, redox-regulated and lysosome-dependent phases that can be quantitatively mapped in real time. By enabling synchronized measurement of oxidative activation, organelle trafficking, fusion, and degradation, the MitoFlare-LysoTracker system establishes a new benchmark for dynamic mitophagy analysis in physiologically relevant models. This platform provides a powerful foundation for mechanistic interrogation of mitochondrial quality control and for accelerating the discovery of therapeutic strategies aimed at restoring mitophagic fidelity in neurodegenerative, cardiovascular, and metabolic diseases.

neuroscience↗

bioRxiv2025

MindSight: A Bio-Inspired Neural Architecture for Visual Restoration via Cortical Electrical Stimulation

Visual impairment is a common condition worldwide, and cortical electrical stimulation is one of the approaches to aid in visual restoration. However, existing methods suffer from limited precision, flexibility, and generalization in generating the desired visual perception. In this paper, we propose a novel deep learning-based algorithm for cortical electrical stimulation, named "MindSight," aimed at enhancing the clarity and accuracy of induced visual perceptions. Our framework introduces three key innovations: (1) A differentiable biophysical model simulating cortical state transitions under electrical stimulation, enabling end-to-end training; (2) A dual-path training architecture combining neural decoding fidelity with phosphene simulation constraints; (3) An attention-guided background gated network for input filtration and, a multi-channel activation constraint to ensure the effectiveness of electrical stimulation. We validated our approach through novel experiments with macaque monkeys, demonstrating superior performance in visual perception tasks. These results highlight the potential of our approach in assisting individuals with visual impairments. Codehttps://github.com/zyj9902/MindSight

bioengineering↗

bioRxiv2024

A Novel Cyanine-Based Fluorescent Dye for Targeted Mitochondrial Imaging in Neurotoxic Conditions and In Vivo Brain Studies

Mitochondrial dysfunction is a key feature of neurodegenerative diseases, often preceding symptoms and influencing disease progression. However, real-time in vivo imaging of mitochondria in the brain is limited by existing dyes like MitoTrackers, which struggle with poor tissue penetration, phototoxicity, and inability to cross the blood-brain barrier (BBB). This study introduces Cy5-PEG4, a novel mitochondrial-targeting dye that overcomes these limitations, enabling high-resolution, non-invasive imaging of mitochondrial dynamics. Cy5-PEG4 effectively labels mitochondria in primary neuronal cells exposed to the SARS-CoV-2 RNYIAQVD peptide, revealing dose-dependent alterations in mitochondrial function that may contribute to COVID-19-related neurodegeneration. Importantly, Cy5-PEG4 crosses the BBB without causing neuroinflammation or toxicity, making it a safe tool for in vivo brain imaging and detailed studies of mitochondrial responses. In 3D cultured cells, Cy5-PEG4 captures dynamic changes in mitochondrial distribution and morphology as cell structures mature, highlighting its potential in neurobiological research, diagnostics, and therapeutic development. These findings support Cy5-PEG4 as a powerful tool for studying disease progression, identifying early biomarkers, and evaluating therapeutic strategies in neurodegenerative disorders and COVID-19.

neuroscience↗

bioRxiv2024

Skull bone marrow-derived immune cells infiltrate the damaged cortex and exhibit anti-inflammatory properties

Identifying the origins and contributions of different immune cell populations following brain injury is crucial for understanding their roles in inflammation and tissue repair. This study investigated the infiltration and phenotypic characteristics of skull bone marrow-derived immune cells in the murine brain after TBI. We performed calvarium transplantation from GFP donor mice and subjected the recipients to controlled cortical impact (CCI) injury 14 days post-transplant. Confocal imaging at 3 days post-CCI revealed GFP+ calvarium-derived cells infiltrating the ipsilateral core lesional area, expressing CD45 and CD11b immune markers. These cells included neutrophil (Ly6G+) and monocyte (Ccr2+) identities. Calvarium-derived GFP+/Iba1+ monocyte/macrophages expressed the efferocytosis receptor MerTK and displayed engulfment of NeuN+ and caspase 3+ apoptotic cells. Phenotypic analysis showed that greater calvarium-derived monocyte/macrophages disproportionately express the anti-inflammatory arginase-1 marker than pro-inflammatory CD86. To differentiate the responses of blood- and calvarium-derived macrophages, we transplanted GFP calvarium skull bone into tdTomato bone marrow chimeric mice, then performed CCI injury 14 days post-transplant. Calvarium-derived GFP+ cells predominantly infiltrated the lesion boundary, while blood-derived TdTomato+ cells dispersed throughout the lesion and peri-lesion. Compared to calvarium-derived cells, more blood-derived cells expressed pro-inflammatory CD86 and displayed altered 3D morphologic traits. These findings uniquely demonstrate that skull bone-derived immune cells infiltrate the brain after injury and contribute to the neuroinflammatory milieu, representing a novel immune cell source that may be further investigated for their causal role in functional outcomes.

neuroscience↗

bioRxiv2024

The do not eat me signal CD47 contributes to microglial phagocytosis defects and autism-like behaviors in 16p11.2 deletion mice

Various pathological characteristics of autism spectrum disorder (ASD) stem from abnormalities in brain resident immune cells, specifically microglia, to prune unnecessary synapses or neural connections during early development. Animal models of ASD exhibit an abundance of synapses in different brain regions, which is strongly linked to the appearance of ASD behaviors. Overexpression of CD47 on neurons acts as a "dont eat me" signal, safeguarding synapses from inappropriate pruning by microglia. Indeed, CD47 overexpression occurs in 16p11.2 deletion carriers, causing decreased synaptic phagocytosis and the manifestation of ASD characteristics. However, the role of CD47 in synaptic pruning impairment leading to ASD phenotypes in the 16p11.2 deletion mouse model is unclear. Moreover, whether blocking CD47 can alleviate ASD mices behavioral deficits remains unknown. Here, we demonstrate a strong link between increased CD47 expression, decreased microglia phagocytosis capacity, and increased impairment in social novelty preference in the 16p11.2 deletion mice. The reduction in microglia phagocytosis caused a rise in excitatory synapses and transmission in the prefrontal cortex of 16p11.2 deletion mice. Importantly, blocking CD47 using a specific CD47 antibody or reducing CD47 expression using a specific shRNA enhanced the microglia phagocytosis and reduced excitatory transmission. Reduction in CD47 expression improved social novelty preference deficits in 16p11.2 mice. These findings demonstrate that CD47 contributes to the ASD phenotypes in the 16p11.2 deletion mice and could be a promising target for the development of treatment for ASD. Significance StatementAutism spectrum disorder (ASD) is a neurological developmental condition characterized by stereotyped behaviors and cognitive deficits. However, therapeutic options for ASD remain limited. Activation of the classical complement system, an innate immune signaling pathway component, supports microglia-mediated synaptic pruning during development and disease. In particular, CD47, a "dont eat me" signal, protects synapses from inappropriate clearance. Here, we investigated the role of CD47 in microglial phagocytosis using the 16p11.2 deletion mouse model, demonstrating that reducing CD47 signaling enhances microglial phagocytose synapses in the prefrontal cortex. This enhancement leads to improved synaptic function and reduced social behavioral deficits. These findings provide mechanistic insights into the role of CD47, laying the groundwork for developing more effective treatments for ASD.

neuroscience↗

bioRxiv2024

Enhancement of spatial learning by 40 Hz visual stimulation requires parvalbumin interneuron-dependent hippocampal neurogenesis

Acute and short-term rhythmic 40 Hz light flicker stimulation has shown promising results in alleviating cognitive impairments in mouse models of Alzheimers disease (AD), stroke, and autism spectrum disorders (ASD). Understanding the long-term impacts and underlying mechanisms is crucial to progress this approach for potential human therapeutic applications. Here, we show that prolonged exposure to 40 Hz light flicker (1 hour per day for 30 days) significantly improved spatial learning and neurogenesis in the dentate gyrus (DG) without harmful behavioral side effects. Mice with transgenic deletion of doublecortin-positive cells (DCXDTR) in the adult hippocampus failed to exhibit enhanced neurogenesis and spatial learning with 40 Hz stimulation. Inactivation or knockout of GABAergic parvalbumin (PV) interneurons reduced the effects of 40 Hz entrainment and neurogenesis enhancement. Mechanistically, the stimulation did not alter the regional microvessel blood flow but significantly raised PV excitability and GABA levels and enhanced inhibitory transmission in the DG. Blocking GABAA receptors reversed the improvements in spatial learning and neurogenesis. These data showed that long-term exposure to 40 Hz light flicker enhances spatial learning through PV-dependent adult neurogenesis, which requires elevated GABA as a critical neurochemical mechanism for sustaining adult neurogenesis. In briefRhythmic 40 Hz light flicker alleviates cognitive impairments in diverse animal models of neurological diseases. Understanding its long-term effects and mechanisms is vital for advancing its therapeutic potential for humans. Here, we show that prolonged exposure to this flicker improves spatial learning and boosts adult neurogenesis in the dentate gyrus. Activation of PV interneurons and GABAergic support for the newborn immature neurons underlie this effect, demonstrating lasting benefits for the treatment of neurological diseases. HighlightsO_LILong-term exposure to 40 Hz light flicker significantly improved spatial learning and neurogenesis in the hippocampus, devoid of adverse effects. C_LIO_LIThe 40 Hz light flicker evoked adult neurogenesis requires the activity of GABAergic inhibitory PV interneurons. C_LIO_LIThe 40 Hz light flicker raised GABA levels and enhanced inhibitory transmission in the DG. C_LIO_LIIncreased GABA serves as a vital neurochemical mechanism to support adult neurogenesis. C_LI

neuroscience↗

bioRxiv2024

Ilamycins are dual inhibitors of ClpX and ClpC1 involved in proteostasis in Mycobacteria

The mycobacterial caseinolytic protease (Clp) system has been recognized as a promising therapeutic target. In this study, we identified two novel ilamycin analogs, ilamycin E (ILE) and ilamycin F (ILF), both targeting the ClpC1 component of the ClpC1P1P2 proteasome. ILE potently disrupts ClpC1P1P2-mediated proteolysis, leading to delayed bactericidal activity, while ILF also binds ClpC1, albeit with lower affinity. Notably, we discovered a unique mutation in clpX and a novel insertion in clpC1, both conferring resistance to ILE and ILF in mycobacterium, validated by gene editing. Furthermore, ILE can also inhibit the proteolytic activity of ClpXP1P2 in a manner dependent on the substrates tag sequence and adaptor. This first demonstration of clpX- and clpC1-mediated ilamycin resistance underscores the potential of ilamycins to target multiple components of the Clp protease system, offering a novel dual-target strategy for combating mycobacterial infections.

microbiology↗

bioRxiv2024

EmbB and EmbC Regulate the Sensitivity of Mycobacterium abscessus to Echinomycin

Treatment of Mycobacterium abscessus (Mab) infection is a major challenge due to its intrinsic resistance to most available drugs. It is thus imperative to find new anti-Mab drugs. In this study, we investigated the activity and intrinsic resistance mechanism of echinomycin (ECH) against Mab. ECH is active against Mab (MIC: 2 {micro}g/mL). The embC gene knockout strain (Mab{Delta}embC) showed hyper-sensitive to ECH (MIC: 0.0078-0.0156 {micro}g/mL). The MICs of ECH-resistant strains screened based on the Mab{Delta}embC strain were 0.25-1 {micro}g/mL. Mutations were found in the EmbB, including Asp306Ala, Asp306Asn, Arg350Gly, Val555Ile, and Gly581Ser, which led to increased resistance to ECH when overexpressed in Mab{Delta}embC individually (0.25-0.5 {micro}g/mL). The EmbB mutants edited by the CRISPR/Cpf1 system became more resistant to ECH (MIC: 0.25-0.5 {micro}g/mL). The permeability of gene-edited and overexpressed Mab strains was reduced, as shown by the ethidium bromide accumulation assay, but it was still significantly higher than that of the parent Mab. To summarize, our study demonstrates that ECH has a strong anti-Mab activity and confirms that EmbB and EmbC are related to the sensitivity of Mab to ECH. EmbB mutation may partially compensate for the function of EmbC. Impact StatementMycobacterium abscessus (Mab) is a rapidly growing, intrinsic multidrug-resistant Mycobacterium. This study demonstrated that echinomycin (ECH) has potent antibacterial activity against Mab, and the mechanism of ECH resistance to Mab is related to EmbB and EmbC. EmbB and EmbC can alter the sensitivity of Mab to ECH by altering the permeability of its cell wall. In addition, there is a functional complementary evolution between EmbB and EmbC to regulate sensitivity to ECH. Overall, our study provides a novel anti-Mab drug candidate ECH and a scientific foundation for developing effective strategies to prevent and control Mab.

microbiology↗

bioRxiv2024

Suppression of epileptic seizures by transcranial activation of K+-selective channelrhodopsin

Optogenetics is a valuable tool for studying the mechanisms of neurological diseases and is now being developed for therapeutic applications. In rodents and macaques, improved channelrhodopsins have been applied to achieve transcranial optogenetic stimulation. While transcranial photoexcitation of neurons has been achieved, noninvasive optogenetic inhibition for treating hyperexcitability-induced neurological disorders has remained elusive. There is a critical need for effective inhibitory optogenetic tools that are highly light-sensitive and capable of suppressing neuronal activity in deep brain tissue. In this study, we developed a highly sensitive K+-conductive channelrhodopsin (hsKCR) by molecular engineering of the recently discovered Hyphochytrium catenoides kalium (potassium) channelrhodopsin 1. Transcranial activation of hsKCR significantly prolongs the time to the first seizure, increases survival, and decreases seizure activity in several mouse epileptic models. Our approach for transcranial optogenetic inhibition of neural hyperactivity may be adapted for cell type-specific neuromodulation in both basic and preclinical settings.

neuroscience↗

bioRxiv2023

Development of Gemcitabine-Modified miRNA Mimics as Cancer Therapeutics for Pancreatic Ductal Adenocarcinoma

Pancreatic cancer, including its most common subtype, pancreatic adenocarcinoma (PDAC), has the lowest five-year survival rate among patients with pancreatic cancer in the United States. Despite advancements in anticancer treatment, the overall median survival for patients with PDAC has not dramatically improved. Therefore, there is an urgent need to develop new strategies of treatment to address this issue. Non-coding RNAs, including microRNAs (miRNAs), have been found to have major roles in carcinogenesis and the subsequent treatment of various cancer types like PDAC. In this study, we developed a treatment strategy by modifying tumor suppressor miRNAs, hsa-miRNA-15a (miR-15a) and hsa-miRNA-194-1 (miR-194), with the nucleoside analog chemotherapeutic gemcitabine (Gem) to create Gem-modified mimics of miR-15a (Gem-miR-15a) and miR-194 (Gem-miR-194). In a panel of PDAC cell lines, we found that Gem-miR-15a and Gem-miR-194 induce cell cycle arrest and apoptosis, and these mimics are potent inhibitors with IC50 values up to several hundred fold less than their native counterparts or Gem alone. Furthermore, we found that Gem-miR-15a and Gem-miR-194 retained miRNA function by downregulating the expression of several key targets including WEE1, CHK1, BMI1, and YAP1 for Gem-miR-15a, and FOXA1 for Gem-miR-194. We also found that our Gem-modified miRNA mimics exhibit an enhanced efficacy compared to Gem alone in patient-derived PDAC organoids. Furthermore, we observed that Gem-miR-15a significantly inhibits PDAC tumor growth in vivo without observing any noticeable signs of toxicity. Overall, our results demonstrate the therapeutic potential of Gem-modified miRNAs as a treatment strategy for PDAC. One Sentence SummaryYuen and Hwang et. al. have developed a potent therapeutic strategy for patients with pancreatic cancer by modifying microRNAs with gemcitabine.

cancer biology↗

bioRxiv2023

Angiopoietin-like 4 promotes the proliferation and migration of epidermal stem cells and contributes to the re-epithelialization of cutaneous wounds

Proliferation and migration of epidermal stem cells (EpSCs) are essential for epithelialization during skin wound healing. Angiopoietin-like 4 (ANGPTL4) has been reported to play an important role in wound healing, but the mechanisms involved are not fully understood. Here we investigate the contribution of ANGPTL4 to full-thickness wound re-epithelialization and the underlying mechanisms using Angptl4 knockout mice. Immunohistochemical staining reveals that ANGPTL4 is significantly upregulated in the basal layer cells of the epidermis around the wound during cutaneous wound healing. ANGPTL4 deficiency impairs wound healing. H & E staining shows that ANGPTL4 deficiency significantly reduces the thickness, length and area of regenerated epidermis postwounding. Immunohistochemical staining for markers of EpSCs (6 integrin and {beta}1 integrin) and cell proliferation (PCNA) shows that the number and proliferation of EpSCs in the basal layer of the epidermis are reduced in ANGPTL4-deficient mice. In vitro studies show that ANGPTL4 deficiency impedes EpSC proliferation, causes cell cycle arrest at the G1 phase and reduced the expression of cyclins D1 and A2, which can be reversed by ANGPTL4 overexpression. ANGPTL4 deletion suppresses EpSC migration, which is also rescued by ANGPTL4 overexpression. Overexpression of ANGPTL4 in EpSCs accelerates cell proliferation and migration. Collectively, our results indicate that ANGPTL4 promotes EpSCs proliferation by upregulating cyclins D1 and A2 expression and accelerating cell cycle transition from G1 to S phase, and ANGPTL4 promotes skin wound re-epithelialization by stimulating EpSC proliferation and migration. Our study reveals a novel mechanism underlying EpSC activation and re-epithelialization during cutaneous wound healing.

cell biology↗

bioRxiv2023

Omics Analysis Unveils the Pathway Involved in the Purple Coloration in Tomato Seedling and Fruits

The purple tomato variety Indigo Rose(InR) is favored due to its bright appearance and abundant anthocyanins. SlHY5 is associated with anthocyanin biosynthesis in Indigo Rose plants. However, residual anthocyanins still present in Slhy5 seedlings and fruit peel indicated there was an anthocyanin induction pathway that is independent of HY5 in plants. The molecular mechanism of color formation in Indigo Rose and Slhy5 mutants is unclear. In this study, we performed omics analysis to clarify the regulatory network underlying coloration in seedling and fruit peel of Indigo Rose and Slhy5 mutant. Results showed that the total amount of anthocyanins in both seedling and fruit of InR were significantly higher than those in Slhy5 mutant and most genes associated with anthocyanin biosynthesis exhibited higher expression levels in InR, suggesting that SlHY5 play pivotal roles in flavonoid biosynthesis both in tomato seedlings and fruit. Yeast two-hybrid (Y2H) results revealed that SlBBX24 physically interacts with SlAN2-like and SlAN2, while SlWRKY44 could interact with SlAN11 protein. Unexpectedly, both SlPIF1 and SlPIF3 were found to interact with SlBBX24, SlAN1 and SlJAF13 by yeast two-hybrid assay. Suppression of SlBBX24 by virus-induced gene silencing (VIGS) retarded the purple coloration of the fruit peel, indicating an important role of SlBBX24 in the regulation of anthocyanin accumulation. These results deepen the understanding of purple color formation in tomato seedling and fruits in an HY5-dependent or independent manner via excavating the genes involved in anthocyanin biosynthesis based on omics analysis.

molecular biology↗

bioRxiv2023

SARS-CoV-2 Envelope protein triggers depression and dysosmia via TLR2 mediated neuroinflammation

BackgroundDepression and dysosmia have been regarded as the main neurological symptoms in COVID-19 patients, the mechanism of which remains unclear. Current studies have demonstrated that SARS-CoV-2 envelope protein served as a pro-inflammatory factor as sensed by Toll like receptor 2 (TLR2), suggesting the viral infection independent pathological feature of E protein. In this study, we aim to determine the role of E protein in depression, dysosmia and associated neuroinflammation in central nervous system (CNS). MethodsDepression and olfactory function were observed in both female and male mice as receiving intracisternal injection of envelope protein. Immunohistochemistry was applied in conjunction with RT-PCR to assess the glial activation, blood-brain barrier status and mediators synthesis in cortex, hippocampus and olfactory bulb. TLR2 was pharmacologically blocked to determine its role in E protein related depression and dysosmia. ResultsIntracisternal injection of envelope protein evoked depression and dysosmia in both female and male mice. Immunohistochemistry suggested that envelope protein upregulated IBA1 and GFAP in cortex, hippocampus and olfactory bulb, while ZO-1 was downregulated. Moreover, IL-1{beta}, TNF-, IL-6, CCL2, MMP2 and CSF1 were upregulated in both cortex and hippocampus, whereas IL-1{beta}, IL-6 and CCL2 were upregulated in olfactory bulb. Furtherly, inhibiting microglia, but not astrocyte, alleviated depression and dysosmia induced by envelope protein. Finally, RT-PCR and immunohistochemistry suggested that TLR2 was upregulated in cortex, hippocampus and olfactory bulb, the blocking of which mitigated depression and dysosmia induced by envelope protein. ConclusionsOur study demonstrates that envelope protein could directly induce depression and dysosmia together with obvious neuroinflammation in CNS. TLR2 mediated depression and dysosmia induced by envelope protein, which could serve as a promising therapeutic target for neurological manifestation in COVID-19 patients.

neuroscience↗

bioRxiv2022

Development of a 5-FU Modified miR-129 Mimic as a Therapeutic for Non-Small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related deaths in the United States with non-small cell lung cancer (NSCLC) accounting for most cases. Despite advances in cancer therapeutics, the 5-year survival rate has remained poor due to several contributing factors, including its resistance to therapeutics. Therefore, there is a pressing need to develop therapeutics that can overcome resistance. Non-coding RNAs, including microRNAs (miRNAs), have been found to contribute to cancer resistance and therapeutics by modulating the expression of several targets involving multiple key mechanisms. In this study, we investigated the therapeutic potential of miR-129 modified with 5-fluorouracil (5-FU) in NSCLC. Our results show that 5-FU modified miR-129 (5-FU-miR-129) inhibits proliferation, induces apoptosis, and retains function as a miRNA in NSCLC cell lines A549 and Calu-1. Notably, we observed that 5-FU-miR-129 was able to overcome resistance to tyrosine kinase inhibitors and chemotherapy in cell lines resistant to erlotinib or 5-FU. Furthermore, we observed that the inhibitory effect of 5-FU-miR-129 can also be achieved in NSCLC cells under vehicle-free conditions. Finally, 5-FU-miR-129 inhibited NSCLC tumor growth and extended survival in vivo without toxic side effects. Altogether, our results demonstrate the potential of 5-FU-miR-129 as a highly potent cancer therapeutic in NSCLC.

cancer biology↗

bioRxiv2022

Development of 5-FU-modified tumor suppressor microRNAs as a platform for novel microRNA-based cancer therapeutics

MicroRNA (miRNAs) are pleiotropic post-transcriptional modulators of gene expression. Its inherently pleiotropic nature make miRNAs strong candidates for the development of cancer therapeutics, yet despite its potential, there remains a challenge to deliver nucleic acid-based therapies into cancer cells. We developed a novel approach to modify miRNAs by replacing the uracil bases with 5-fluorouracil (5-FU) in the guide strand of tumor suppressor miRNAs, thereby combining the therapeutic effect of 5-FU with tumor suppressive effect of miRNAs to create a potent, multi-targeted therapeutic molecule without altering its native RNA interference (RNAi) function. To demonstrate the general applicability of this approach to other tumor suppressive miRNAs, we screened a panel of 12 novel miRNA mimetics in several cancer types including leukemia, breast, gastric, lung, and pancreatic cancer. Our results show that 5-FU-modified miRNA mimetics have increased potency (low nM range) in inhibiting cancer cell proliferation and that these mimetics can be delivered into cancer cells without delivery vehicle both in vitro and in vivo, thus representing significant advancements in the development of therapeutic miRNAs for cancer. This work demonstrates the potential of fluoropyrimidine modifications that can be broadly applicable and may serve as a platform technology for future miRNA and nucleic acid-based therapeutics.

cancer biology↗