Biology subjects

Ban, J.

Publications and source records attributed to Ban, J..

7 recordsLinked to original sources

bioRxiv2026

FoxO3a and miR-34a-3p Are Involved in Oxidative Stress-Induced Dysfunction of Human Endothelial Progenitor Cells

BackgroundEndothelial progenitor cells (EPCs) contribute to endothelial repair and neovascularization, and EPC dysfunction is closely associated with oxidative stress-related vascular injury. Forkhead box O3a (FoxO3a) regulates cellular stress responses, whereas miR-34a has been implicated in endothelial dysfunction, senescence, and apoptosis. However, the relationship between FoxO3a and miR-34a-3p in oxidatively injured EPCs remains incompletely defined. ObjectiveThis study investigated the role of FoxO3a in H2O2-induced EPC dysfunction and examined whether miR-34a-3p directly interacts with the FoxO3a 3' untranslated region (3'UTR). MethodsHuman umbilical cord blood-derived EPCs were identified by DiI-ac-LDL uptake, FITC-UEA-1 binding, and the expression of EPC-related markers. Oxidative stress was induced by H2O2. Cell viability, apoptosis, and angiogenic capacity were evaluated using CCK-8 assay, Annexin V/7-AAD flow cytometry, and Matrigel tube formation assay, respectively. FoxO3a expression was modulated using adenoviral overexpression or knockdown vectors, and miR-34a was modulated using mimics or antagomir. FoxO3a and miR-34a expression levels were detected by Western blot and qPCR. A dual-luciferase reporter assay was used to verify the interaction between hsa-miR-34a-3p and the FoxO3a 3'UTR. ResultsH2O2 reduced EPC viability, increased apoptosis, and impaired tube formation in a concentration-dependent manner. H2O2 increased FoxO3a protein abundance and miR-34a expression, whereas FoxO3a mRNA did not change markedly. FoxO3a overexpression aggravated, whereas FoxO3a knockdown partially alleviated, H2O2-induced EPC dysfunction. Similarly, miR-34a mimics further suppressed EPC viability and tube formation, while miR-34a antagomir exerted a protective effect. Dual-luciferase reporter analysis showed that hsa-miR-34a-3p significantly reduced the activity of the wild-type FoxO3a 3'UTR reporter, while mutation of the predicted binding site abolished this suppression. ConclusionFoxO3a and miR-34a participate in oxidative stress-induced EPC dysfunction. The dual-luciferase data demonstrate that hsa-miR-34a-3p directly targets the FoxO3a 3'UTR, suggesting the presence of miR-34a-3p-mediated post-transcriptional feedback within the FoxO3a-related stress-response network in EPCs.

biochemistry↗

bioRxiv2025

Deep-learning-assisted SICM for enhanced real-time imaging of nanoscale biological dynamics

Scanning Ion Conductance Microscopy (SICM) provides high-resolution, nanoscale imaging of living cells, but it is generally limited by a slow scan rate, making it challenging to capture dynamic processes in real time. To tackle this challenge, we propose an integrated data acquisition and computational framework that improves the temporal resolution of SICM by selectively skipping certain scan lines. A partial convolutional neural network (Partial-CNN) model is developed and trained on SICM images and their corresponding masks to reconstruct the complete images from the under-sampled data, ensuring the retention of structural integrity. This approach significantly reduces the image acquisition time (i.e., by 30-60%) without compromising quality, as validated through multiple quantitative metrics. Compared to conventional deep learning methods, the Partial-CNN demonstrates higher accuracy in reconstructing fine details and maintaining consistent height maps across skipped regions. We show that this method provides an increased temporal resolution and retains image fidelity, making it suitable for real-time dynamic SICM imaging and improving the smart scanning microscopy applications in time-resolved biological imaging. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/663539v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@562d32org.highwire.dtl.DTLVardef@1b12dcaorg.highwire.dtl.DTLVardef@13535f3org.highwire.dtl.DTLVardef@6904f0_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2021

Discovery of μ,δ-Opioid receptor dual biased agonists that overcome the limitation of prior biased agonists

Morphine is widely used to manage pain in patients, although the risk of side effects is significant. The use of biased agonists to the G protein of -opioid receptors has been suggested as a potential solution, although Oliceridine and PZM21 have previously failed to demonstrate benefits in clinical studies. An amplification-induced confusion in the process of comparing G protein and beta-arrestin pathways may account for previous biased agonist mis-identification. Here, we have devised a strategy to discover biased agonists with intrinsic efficacy. We computationally simulated 430,000 molecular dockings to the -opioid receptor to construct a compound library. Hits were then verified by experiment. Using the verified compounds, we performed simulations to build a second library with a common scaffold, and selected compounds which show biased features to and {delta}-opioid receptors through a cell-based assay. Three compounds (ID110460001, ID110460002, and ID110460003) with a dual biased agonistic effect for and {delta}-opioid receptors were identified. These candidates are full agonists for the -opioid receptor, and they show specific binding modes. Based on our findings, we expect our novel compound to act as a biased agonist than conventional drugs such as Oliceridine.

pharmacology and toxicology↗

bioRxiv2020

Endocardial/endothelial angiocrines regulate cardiomyocyte development and maturation and induce features of ventricular non-compaction

Non-compaction cardiomyopathy is a devastating genetic disease caused by insufficient consolidation of ventricular wall muscle that can result in inadequate cardiac performance. Despite being the third most common cardiomyopathy, the mechanisms underlying the disease, including the cell types involved, are poorly understood. We have previously shown that endothelial cell-specific deletion of the chromatin remodeler gene Ino80 results in defective coronary vessel development that leads to ventricular noncompaction in embryonic mouse hearts. Here, we used single-cell RNA-sequencing to characterize endothelial and endocardial defects in Ino80-deficient hearts. We observed a pathological endocardial cell population in the non-compacted hearts, and identified multiple dysregulated angiocrine factors that dramatically affected cardiomyocyte behavior. We identified Col15A1 as a coronary vessel-secreted angiocrine factor, downregulated by Ino80-deficiency, that functioned to promote cardiomyocyte proliferation. Furthermore, mutant endocardial and endothelial cells (ECs) upregulated expression of secreted factors, such as Tgfbi, Igfbp3, Isg15, and Adm, which decreased cardiomyocyte proliferation and increased maturation. These findings support a model where coronary ECs normally promote myocardial compaction through secreted factors, but that endocardial and ECs can secrete factors that contribute to non-compaction under pathological conditions.

developmental biology↗

bioRxiv2018

Activation of RIG-I-mediated antiviral signaling triggers autophagy through the MAVS-TRAF6-Beclin-1 signaling axis

Autophagy has been implicated in innate immune responses against various intracellular pathogens. Recent studies have reported that autophagy can be triggered by pathogen recognizing sensors, including Toll-like receptors and cyclic guanosine monophosphate-adenosine monophosphate synthase, to participate in innate immunity. In the present study, we examined whether the RIG-I signaling pathway, which detects viral infections by recognizing viral RNA, triggers the autophagic process. The introduction of polyI:C into the cytoplasm, or Sendai virus infection, significantly induced autophagy in normal cells but not in RIG-I-deficient cells. PolyI:C transfection or Sendai virus infection induced autophagy in the cells lacking type-I interferon signaling. This demonstrated that the effect was not due to interferon signaling. RIG-I-mediated autophagy diminished by the deficiency of mitochondrial antiviral signaling protein (MAVS) or tumor necrosis factor receptor-associated factor (TRAF)6, showing that the RIG-I-MAVS-TRAF6 signaling axis was critical for RIG-I-mediated autophagy. We also found that Beclin-1 was translocated to the mitochondria, and it interacted with TRAF6 upon RIG-I activation. Furthermore, Beclin-1 underwent K63-polyubiquitination upon RIG-I activation, and the ubiquitination decreased in TRAF6-deficient cells. This suggests that the RIG-I-MAVS-TRAF6 axis induced K63-linked polyubiquitination of Beclin-1, which has been implicated in triggering autophagy. Collectively, the results of this study show that the recognition of viral infection by RIG-I is capable of inducing autophagy to control viral replication. As deficient autophagy increases the type-I interferon response, the induction of autophagy by the RIG-I pathway might also contribute to preventing an excessive interferon response as a negative-feedback mechanism.\n\nImportanceMammalian cells utilize various innate immune sensors to detect pathogens. Among those sensors, RIG-I recognizes viral RNA to detect intracellular viral replication. Although cells experience diverse physiological changes upon viral infection, studies to understand the role of RIG-I signaling have focused on the induction of type-I interferon. Autophagy is a process that sequesters cytosolic regions and degrades the contents to maintain cellular homeostasis. Autophagy participates in the immune system, and has been known to be triggered by some innate immune sensors, such as TLR4 and cGAS. We demonstrated that autophagy can be triggered by the activation of RIG-I. In addition, we also proved that MAVS-TRAF6 downstream signaling is crucial for the process. Beclin-1, a key molecule in autophagy, is translocated to mitochondria, where it undergoes K63-ubiquitination in a TRAF6-dependent manner upon RIG-I activation. As autophagy negatively regulates RIG-I-mediated signaling, the RIG-I-mediated activation of autophagy may function as a negative-feedback mechanism.

immunology↗

bioRxiv2017

Synthetic lethality between the cohesin subunits STAG1 and STAG2 in diverse cancer contexts

Recent genome analyses have identified recurrent mutations in the cohesin complex in a wide range of human cancers. Here we demonstrate that the most frequently mutated subunit of the cohesin complex, STAG2, displays a strong synthetic lethal interaction with its paralog STAG1. Mechanistically, STAG1 loss abrogates sister chromatid cohesion in STAG2 mutated but not in wild-type cells leading to mitotic catastrophe, defective cell division and apoptosis. STAG1 inactivation inhibits the proliferation of STAG2 mutated but not wild-type bladder cancer and Ewing sarcoma cell lines. Restoration of STAG2 expression in a mutated bladder cancer model alleviates the dependency on STAG1. Thus, STAG1 and STAG2 support sister chromatid cohesion to redundantly ensure cell survival. STAG1 represents a vulnerability of cancer cells carrying mutations in the major emerging tumor suppressor STAG2 across different cancer contexts. Exploiting synthetic lethal interactions to target recurrent cohesin mutations in cancer, e.g. by inhibiting STAG1, holds the promise for the development of selective therapeutics.

cancer biology↗

bioRxiv2017

Hardwired synthetic lethality within the cohesin complex in human cancer cells

Recent genome analyses have identified recurrent mutations in the cohesin complex in a wide range of human cancers. Here we demonstrate that the most frequently mutated subunit of the cohesin complex, STAG2, displays a strong synthetic lethal interaction with its paralog STAG1. Mechanistically, STAG1 loss abrogates sister chromatid cohesion in STAG2 mutated but not in wild-type cells leading to mitotic catastrophe, defective cell division and apoptosis. STAG1 inactivation inhibits the proliferation of STAG2 mutated but not wild-type bladder cancer and Ewing sarcoma cell lines. Restoration of STAG2 expression in a mutated bladder cancer model alleviates the dependency on STAG1. Thus, STAG1 and STAG2 act redundantly to support sister chromatid cohesion and cell survival. STAG1 represents a hardwired, context independent vulnerability of cancer cells carrying mutations in the major emerging tumor suppressor STAG2. Exploiting synthetic lethal interactions to target recurrent cohesin mutations in cancer, e.g. by inhibiting STAG1, holds the promise for the development of selective therapeutics.

cell biology↗