Biology subjects

Jiang, X.

Publications and source records attributed to Jiang, X..

At least 109 records · Page 6Linked to original sources

bioRxiv2025

Mutations in the ubiA gene are the major mechanism of ethambutol resistance in Mycobacterium avium

Mycobacterium avium-intracellulare complex (MAC) infections are the most common nontuberculous mycobacterial (NTM) infections, and ethambutol (EMB) is one of the main therapeutic agents used to treat MAC infections. However, the EMB resistance profile and its resistance mechanisms in M. avium remain poorly understood. This study determined the minimum inhibitory concentration (MIC) on 40 M. avium clinical strains, revealing that 97.5% (39/40) of the strains were intermediate (MIC=4 g/mL) or resistant (MIC[≥]8 g/mL) to EMB. One susceptible clinical isolate strain 245 (MIC=2 g/mL) was picked for EMB-resistant mutant isolation, and a total of 121 resistant mutants were isolated and subjected to whole-genome sequencing or Sanger sequencing. Integrated analysis revealed that 94.21% (114/121) of the mutants carried mutations in the ubiA gene, which encodes DPPR (decaprenylphosphoryl-{beta}-D-5-phosphoribose) synthase - an enzyme involved in cell wall biosynthesis that has been associated with high-level EMB resistance in M. tuberculosis. Complementation with the wild-type ubiA gene restored EMB susceptibility in EMB-resistant mutants and clinical strain 322 (EMB MIC=64 g/mL) with ubiA mutation, reducing the MICs from 32 g/mL to 4 g/mL and from 64 g/mL to 8 g/mL, respectively. This study indicates that the ubiA mutation is the major mechanism of EMB resistance in M. avium, which should facilitate the development of molecular tests for rapid detection of resistance in this organism.

microbiology↗

bioRxiv2025

Genes required for Mycobacterium tuberculosis to survive the transition from aerosol to pulmonary alveolar lining fluid and early infection in a model of transmission

Mycobacterium tuberculosis (Mtb) must survive multiple changes in environment for aerosol transmission. Our genome-wide screen for rehydration of modeled aerosols in surrogate pulmonary alveolar lining fluid identified a survival-sustaining role for 22 genes not required for survival during earlier stages of transmission, 20 of which are non-essential in routine culture. Thirteen genes were also needed for Mtb to survive in alveolar macrophages after passing through the earlier stages of transmission. Nine 9 of the 13 were needed for full infectivity of aerosols in mice. Seven of the genes sustaining the intra-alveolar survival of aerosolized Mtb are likely to regulate Mtbs uptake, catabolism or synthesis of lipids as regulated by cAMP. Our results reveal a dynamic form of conditional essentiality that only emerges after bacteria experience a sequence of other pathophysiologically relevant conditions. These findings enlarge Mtbs candidate transmission survival genome with stage-specific genes encoding potential targets for blocking tuberculosis transmission.

microbiology↗

bioRxiv2025

ATF4 alleviates doxorubicin-induced cardiomyopathy through H2S-mediated antioxidation

BackgroundDoxorubicin (DOX) remains a cornerstone in the treatment of various cancers. However, its clinical utilization is significantly hampered by dose-dependent cardiotoxicity. The generation of reactive oxygen species (ROS) constitutes the central component of the pathogenesis of DOX-induced cardiotoxicity. Activating transcription factor 4 (ATF4) has been demonstrated to exert a cardioprotective effect and augment cardiac antioxidative capacity in settings of heart failure. However, the role of ATF4 in DOX-induced cardiomyopathy (DIC) remains unknown. MethodsTo explore the role of ATF4 in DOX-induced cardiomyopathy, cardiac-specific ATF4 conditional heterozygous mice and AAV9 mediated ATF4 overexpression mouse models were utilized. Cardiac function was assessed by echocardiography. The upstream regulator and downstream mediator of ATF4 were evaluated using RNA-seq analysis and further verified using ChIP assay and luciferase reporter assay. ResultsWe found a substantial decrease in ATF4 expression levels in the heart of DIC mice. ATF4+/- mice exhibited a higher degree of susceptibility to DOX-induced cardiotoxicity in comparison with ATF4flox/flox mice, as evidenced by the manifestation of more severe cardiac dysfunction and a significantly earlier mortality rate. In contrast, cardiacc-specific overexpression ATF4 by AAV9 confers robust cardioprotection against DOX-induced cardiomyopathy. Mechanistically, we identified the upstream regulator of ATF4 as KLF16, which was significantly suppressed during DOX treatment. Further, the decrease of ATF4 led to a reduction in cystathionine {gamma}-lyase (CSE) transcription and hydrogen sulfide (H2S) production in the context of DOX-induced cardiotoxicity. ChIP and luciferase reporter assays revealed that ATF4 functioned as the transcription factor of the CSE gene, which is a key enzyme in the synthesis of H2S to counteract oxidative stress. Consistently, ROS scavengers or H2S donors was shown to mitigate the consequences of ATF4 deficiency. In contrast, the ectopic expression of ATF4 mitigated oxidative stress and apoptosis in DOX-induced cardiotoxicity, both in vivo and in vitro. ConclusionsOur study revealed a novel function of ATF4 in counteracting oxidative stress in DOX cardiotoxicity by promoting the transcription of CSE. ATF4 may represent a promising therapeutic target for the treatment of DOX-induced cardiomyopathy.

pathology↗

bioRxiv2025

Mycobacterium tuberculosis, Mycobacterium kansasii and Rhodococcus equi induce macrophage necroptosis in the presence of a caspase inhibitor acting on a non-canonical target(s)

Macrophages are the predominant cell type infected by Mycobacterium tuberculosis (Mtb) in tuberculosis (TB). Death of Mtb-infected macrophages promotes tissue pathology and releases Mtb to infect other cells, suggesting that inhibiting the death of Mtb-infected macrophages could be an adjunctive treatment of TB. Prospects for such an intervention depend on identifying the molecular pathways leading to cell death. We previously reported that the death of Mtb-infected mouse macrophages in vitro depends on type I interferon (IFN) and that the ensuing upregulation of cis-aconitate decarboxylase (ACOD1; IRG1) contributes to cell death by exacerbating Mtb-induced lysosomal membrane permeabilization. Here we report that death of Mtb-infected primary mouse macrophages in vitro became necroptotic and die faster in the presence of benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD) acting on a target other than caspase-8. Macrophages infected with Mycobacterium kansasii and Rhodococcus equi likewise underwent z-VAD-dependent necroptosis. In C57BL/6 mice, which are relatively TB-resistant, we saw no impact of MLKL deficiency on bacterial burden or pulmonary pathology. In contrast, in Sp140-/- mice on the C57BL/6 background, which express high levels of type I IFN after Mtb infection and develop necrotic pulmonary lesions, MLKL-deficiency reduced bacterial burden and pathology after high-dose infection. This report illustrates that off-target action(s) of a caspase-8 inhibitor can switch the cell death pathway to necroptosis in macrophages infected with various Gram-positive pathogens. In turn, this opens the possibility that pathophysiologic circumstances may lead to inhibition of the same target(s) that z-VAD inhibited in our studies. That may be what allows MLKL to exacerbate tuberculosis in mice that are prone to formation of necrotic lesions. Author SummaryTuberculosis (TB), caused by the bacillus Mycobacterium tuberculosis (Mtb), led to about 1.3 million deaths in 2023. The rapid emergence of drug resistance and slow pace of new drug development prompt attention to adjunctive host-directed therapies, an approach that relies on a thorough and detailed understanding of host-Mtb interactions. Mtb infection of macrophages can kill them, promoting tissue pathology and releasing of Mtb to infect other cells. Here we find that a pan-caspase inhibitor z-VAD hastened the death of Mtb-infected macrophages and converted the mode of cell death to RIPK1-RIPK3-MLKL-dependent necroptosis. However, the functional target(s) of z-VAD-FMK and the activation mechanism of RIPK3 differ from the canonical pathways. The pan-caspase inhibitor also promoted rapid, necroptotic death of macrophages infected with Mycobacterium kansasii and Rhodococcus equi. We further found that MLKL-deficiency in Sp140-/- mice on the C57BL/6 background resulted in less weight loss, lower Mtb burdens and mitigation of lung pathology after high-dose Mtb infection. Our findings suggest that necroptosis can contribute to TB pathogenesis in some circumstances. Further identification of the death pathway-switching mechanism could deepen our understanding of host-Mtb interactions and aid in the design of adjunctive host-directed therapies.

microbiology↗

bioRxiv2025

Ginkgolic acid attenuates e chinococcus granulosus infection-induced hepatic fibrosis by inhibiting Smad4 SUMOylation

BackgroundThe SUMOylation modification is closely linked to the progression of fibrotic diseases, yet its role in hepatic fibrosis associated with cystic echinococcosis (CE) remains unclear. This study aimed to investigate the function of SUMOylation in CE-related hepatic fibrosis and evaluate the anti-fibrotic effects and mechanisms of ginkgolic acid (GA) via regulation of the SUMOylation pathway. MethodologyPeri-lesional (PL) and adjacent normal (AN) liver tissues from CE patients were collected to examine histopathology and SUMO pathway proteins. A CE-infected mouse model was established and treated with GA to assess cyst burden, serum TGF-{beta}1 levels, hepatic fibrosis markers, and SUMO-related proteins. In vitro, macrophages and hepatic stellate cells (HSCs, LX-2 line) were stimulated with Echinococcus granulosus cyst fluid (EgCF) or TGF-{beta}1 to evaluate GAs effects on macrophage polarization (CD206/CD86), HSC activation (-SMA/PCNA), Smad4 SUMOylation, and nuclear translocation. Macrophage-HSC crosstalk was investigated via conditioned medium co-culture assays. ResultFibrosis was exacerbated in peri-lesional liver tissues of CE patients, accompanied by SUMO pathway activation. GA significantly alleviated hepatic fibrosis in CE mice and reversed SUMO pathway dysregulation. Mechanistically, GA inhibited EgCF-induced pro-fibrotic M2 macrophage polarization and blocked Smad4 SUMOylation and nuclear translocation by modulating SUMOylation. Furthermore, GA directly suppressed HSC activation and bidirectionally disrupted the pro-fibrotic crosstalk between macrophages and HSCs under EgCF stimulation, ultimately alleviating fibrosis. ConclusionThis study reveals the critical role of SUMOylation modification in CE-associated hepatic fibrosis and elucidates a novel anti-fibrotic mechanism whereby GA targets the SUMOylation-Smad4 axis to regulate the immune microenvironment. Author summaryThis study demonstrates aberrant activation of the SUMOylation pathway during hepatic fibrosis progression in cystic echinococcosis (CE), characterized by upregulated SUMO1/Ubc9 expression and downregulated SENP1 in peri-cystic liver tissue. Ginkgolic acid (GA) intervention significantly attenuated CE-associated liver fibrosis in mice, evidenced by reduced cyst volume, decreased TGF-{beta}1 levels, and suppressed expression of fibrotic markers (-SMA/COL1A1). GA concurrently reversed dysregulated SUMO pathway protein expression. Mechanistically, GA upregulates the deSUMOylating enzyme SENP1, thereby inhibiting Echinococcus granulosus cyst fluid (EgCF)-induced SUMOylation and nuclear translocation of Smad4. This blockade impedes macrophage polarization toward the pro-fibrotic M2 phenotype (CD206{downarrow}) and suppresses hepatic stellate cell (HSC) activation (-SMA/PCNA{downarrow}). Furthermore, GA disrupts the pro-fibrotic bidirectional crosstalk between HSCs and macrophages. Collectively, these findings indicate that GA ameliorates CE-induced hepatic fibrosis by targeting the SUMO-Smad4 axis to modulate the immune microenvironment, providing a novel therapeutic strategy.

molecular biology↗

bioRxiv2025

16S rRNA Survey Reveals the Potential of Oral Microbiota in Distinguishing Patients with Chronic Heart Failure from Healthy Controls

BackgroundOral microbiota can reflect physiological functions and pathological conditions in human body. Patients with chronic heart failure (CHF) exhibit distinct oral health status compared to healthy controls (HCs), which is attributed to the differences in dominant microbial communities present in the oral cavity. Up to date, there are few studies examined the association between CHF and dominant oral microbiota. To fill in this research gap, this study aimed to investigate the differences of oral microbiota between CHF patients and HCs, to identify valuable novel biomarkers for CHF. MethodsChronic heart failure patients and healthy volunteers were recruited. Oral microbiota samples were then collected using oral swabs, and 16S rRNA sequencing was employed to analyze the microbiota. Statistical analysis was conducted to identify key bacteria at multiple taxonomic levels in the oral microbiota samples from both the CHF patient and healthy control groups, with a focus on core genera to identify potential biomarkers and evaluate their diagnostic efficacy. ResultsThere were 60 CHF patients and 30 HCs were recruited, with 42 CHF patients with New York Heart Association (NYHA) functional class II-IV and 28 HCs were included in the final analysis. The alpha diversity was higher in HCs, while beta diversity was higher in CHF patients. The CHF patients showed significant differences from HCs at five gene (phylum, class, order, family and genus) levels by analyzing the relative richness of microbiota at different taxomal levels. Altogether 14 microbes could distinguish CHF patients from HCs, i.e., Abiotrophia, Butyrivibrio, Lactobacillus, Capnocytophaga and Neisseria which are more abundant in CHF patients, and Actinomyces, Anaerovorax, Eubacterium, Kingella, Mogibacterium, Peptococcus, Peptostreptococcus, Solobacterium and TM7_genus_incertae_sedis which are more abundant in HCs. Furthermore, the AUC of their combined diagnosis was 83.7% (95% confidential interval 74.1%-93.3%), which have high reliability for the diagnostic significance. In accordance to Spearmans correlation, Eubacterium, Solobacterium and Rhizobium were core genera and the abundance of Eubacterium and Solobacterium exhibited downward trends as NYHA class increases. ConclusionThis study revealed the dysbiosis of the oral microbiota in CHF patients and identified potential biomarkers for CHF diagnosis and management. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/669863v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@d60f6eorg.highwire.dtl.DTLVardef@18f17ceorg.highwire.dtl.DTLVardef@163f0daorg.highwire.dtl.DTLVardef@599bcd_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2025

Editing of ADA2 Point Mutation in Human Hematopoietic Stem Cells

BackgroundThe homozygous ADA2: c.506G>A (p.Arg169Gln; p.R169Q) variant accounts for majority of Deficiency in Adenosine Deaminase 2 (DADA2). This monogenic disorder may be amenable to ex vivo gene therapy by correcting the pathogenic mutation in CD34+ hematopoietic stem and progenitor cells (HSPCs). ObjectiveTo apply CRISPR-Cas9 and homology-directed repair (HDR) as a surrogate strategy to model correction of the pathogenic ADA2 c.506G>A variant in healthy cord blood HSPCs. MethodsHSPCs were electroporated with optimised CRISPR-Cas9 editing reagents, and editing outcomes, including HDR and on-target deletions, were quantified by ddPCR. Cell functionality was assessed through colony-forming unit (CFU) assays and by xenotransplantation into NOD SCID Gamma (NSG) mice. Two HDR enhancement strategies were tested: (1) genetic inhibitors of p53 and non-homologous end joining (NHEJ) pathways, and (2) pharmacological NHEJ inhibition. ResultsSmall-molecule NHEJ inhibitors increased HDR efficiency approximately two-fold (from [~]40 % to [~]80 %). Edited HSPCs retained normal CFU capacity and successfully engrafted in NSG mice. However, up to 8 % of edited cells exhibited on-target chromosome loss, though this declined over time. Up to 40 % of T cells and fibroblasts demonstrated similar losses under NHEJ inhibitors treatment. In contrast, genetically encoded inhibitors did not improve HDR. ConclusionThe ADA2 p. c.506G>A variant can be effectively edited employing surrogate strategy in HSPCs without impairing functionality. Although pharmacological inhibition of NHEJ enhances HDR efficiency, it also increases the risk of on-target chromosome aberrations, highlighting the need for careful consideration of the associated risks and benefits in therapeutic gene editing. Key messages1) The ADA2 p.R169Q variant can be efficiently corrected via HDR, and the edited CD34+ HSPCs retain their engraftment capability in NSG mice. 2) Pharmacological inhibition of NHEJ using small-molecule inhibitors increases HDR efficiency but is associated with significant on-target deletions and chromosomal arm loss, particularly in differentiated cell types, and in a donor-dependent manner. Capsule summaryThe ADA2 p.R169Q variant is a viable target for precision gene editing in hematopoietic stem cells. Although inhibition of NHEJ improves HDR efficiency, it concomitantly increases the risk of large on-target deletions, particularly in differentiated cells.

bioengineering↗

bioRxiv2025

A high-throughput heterologous expression platform for plant synthetic biology based on Arabidopsis suspension cells

Efficient heterologous expression platforms are essential for plant synthetic biology, particularly for engineering complex multigene pathways. Here, we establish a high-throughput system for both transient and stable transformation of Arabidopsis thaliana suspension cells using plant cell pack infiltration. This method requires no specialized equipment or consumables and is compatible with several cell lines. It enables rapid generation of 100 g of transgenic cells within two weeks and allows expression of at least 6 stacked genes from a single construct. We characterized constitutive promoters for gene expression in Arabidopsis cells and validated plastid targeting peptides. A library of NifB homologs was screened for expression and solubility and several archaeal variants suitable for plant expression were identified. We further engineered stable cell lines expressing up to six genes, encoding the NifB module components NifU, NifS, FdxN, and NifB, demonstrating that the newly developed platform integrates into an established workflow for nitrogenase engineering. The platform accelerates design-build-test cycles and facilitates the production of delicate proteins that require large amounts of transgenic biomass. It thus represents a versatile and scalable tool for advancing synthetic biology and for tackling major biotechnological challenges, such as biological nitrogen fixation. HighlightWe developed a fast and scalable expression platform in Arabidopsis suspension cells, enabling transient and stable multigene expression for applications in plant synthetic biology such as nitrogenase engineering.

plant biology↗

bioRxiv2025

Tripleknock: predicting lethal effect of three-gene knockout in bacteria by deep learning

Investigating the lethal effect of multi-gene knockout is essential for discovering novel antibiotics targets and metabolic engineering. Unlike single genes or gene pairs, three-gene combinations involve more intricate interactions, making experimental screening time-consuming. Computational methods, particularly Genome-scale metabolic Model (GEM)-based Flux Balance Analysis (FBA), requires constructing new GEMs from experimental data, limiting its use for new species. Moreover, using FBA for three-gene knockout screening could take several years. Therefore, a faster and GEMs-independent approach is needed to facilitate genome-wide three-gene knockout screening. Here, we introduce Tripleknock, for predicting the lethal effects of three-gene knockouts. Tripleknock was trained using whole-genome data from Escherichia coli K-12 MG1655, and three-gene knockout simulations using FBA. The model uses a threshold of 90% reduction in cell growth to define lethal effect as the prediction output. Compared to FBA, Tripleknock achieves predictions approximately 20 times faster, reaching an average cross-species F1 score of 0.77 on six pathogenic species within the Enterobacteriaceae family. For closely related species such as pathogenic E. coli and Shigella, Tripleknock reaches F1 scores exceeding 0.83. To our knowledge, Tripleknock is the first end-to-end model for predicting lethal effects of three-gene knockout in bacteria. Data availabilityTripleknock is publicly available at: https://github.com/Peneapple/Tripleknock

bioinformatics↗

bioRxiv2025

A Precision Ultrasound-Localized Sonoporation-Equipment (PULSE) Enabling Intratumoral Delivery for Cancer Immunotherapy

Cancer immunotherapy offers a promising long-term treatment for solid tumors by activating the immune system, but side effects and systemic toxicity limit its broad clinical translation. While intratumoral delivery addresses these limitations, elevated stiffness within solid tumors continues to hinder both intracellular and extracellular delivery. Here, a novel therapeutic platform, the Precision Ultrasound-Localized Sonoporation-Equipment (PULSE), is presented to enable spatiotemporally controlled, ultrasound-mediated gene and drug delivery for intratumoral immunotherapy. The PULSE incorporates forward and sideward-looking miniaturized ultrasound transducers, integrated into either a 7-French catheter (cPULSE) or a 16-gauge needle (nPULSE), to minimally invasively sonicate a centimeter-sized tumor. Following the design, prototyping, and characterization of PULSE, its dual capability for intracellular and extracellular delivery is demonstrated through comprehensive in vitro cell-based sonoporation tests and phantom-based drug penetration tests. Luciferase assays (activity: ~104 RLU/g level) in the cell studies confirm significantly enhanced gene transfection with cPULSE, while increased dye diffusion (width: ~1 cm level) in the phantom tests validates improved perfusion with nPULSE. The reported PULSE shows promise for spatiotemporally precise, controlled, and localized therapeutic delivery in early-stage tumors for intratumoral immunotherapy.

bioengineering↗

bioRxiv2025

NTM-DB: A Comprehensive Non-Tuberculosis Mycobacteria Genomic Database

Non-tuberculous mycobacteria (NTM) are a major group of environmental bacteria, with approximately one-third of them causing serious human infections, particularly respiratory diseases. The global rise in the prevalence and severity of NTM infections has posed a major public health challenge. While high-throughput sequencing has generated vast genomic data on NTM, there remains a lack of comprehensive resources for cross-species genomic analysis. To address these limitations, we have developed a specialized database called NTM-DB (https://ngdc.cncb.ac.cn/ntmdb) tailored for NTM researchers and clinicians. NTM-DB offers the most comprehensive collection of NTM genomic and bioinformatic resources, including 16,469 genome assemblies (13,134 newly assembled genomes), 189 type/standard strain genomes representing 177 species and 12 subspecies, 705 MLST types, 33,240 resistance genes, and 74,315 virulence genes. A user-friendly interactive website has been constructed to enable efficient browsing, MLST profiling, searching, online analysis, and downloading of the aforementioned data. Notably, with online analysis tools, users can perform customized genotyping, cross-species phylogeny, pan-genome, and virulence and drug resistance gene annotation analyses using our data and/or their uploaded data. Overall, with its comprehensive data, intuitive interface, and powerful analysis tools, NTM-DB serves as an important resource and reference for NTM researchers and clinicians, improving diagnosis and treatment for various NTM-related diseases, and supporting both scientific discovery and clinical practice.

microbiology↗

bioRxiv2025

Conformations and sequence determinants in the lipid binding of an adhesive peptide derived from Vibrio cholerae biofilm

Surface adhesion is critical to the survival of pathogenic bacteria both in natural niches and during infections, often via forming matrix-embedded communities called biofilms. We previously identified a 57-amino acid peptide (Bap1-57aa) as a key contributor to biofilm adhesion of the pandemic pathogen Vibrio cholerae to various surfaces including lipid membranes. Here, we combine biophysical, computational, and genetic approaches to elucidate the molecular mechanism. A central aromatic-rich motif anchors the peptide to lipid bilayers while peripheral pseudo repeats enhance binding through avidity. Surprisingly, the core motif undergoes a lipid-induced conformational transition into a {beta}-hairpin, enabling robust membrane insertion. Moreover, the biofilm-derived peptide, conserved in several other Vibrio species, can adhere to model host surfaces and is sensitive to membrane curvature. Our results provide molecular insight into biofilm adhesion and may lead to new strategies for targeted biofilm removal and the design of bioinspired underwater adhesives. TeaserA short peptide from Vibrio cholerae binds lipids using a unique {beta}-hairpin motif and contributes to host colonization.

microbiology↗

bioRxiv2025

Isoliensinine Ameliorates Pathological Cardiac Hypertrophy After Aerobic Exercise by Activating Cytochrome c Oxidase Subunit 6A2

Pathological cardiac hypertrophy is an abnormal remodeling process of the heart under chronic pressure overload, characterized by myocardial fibrosis, apoptosis, and progressive decline in cardiac function, ultimately leading to heart failure or death. Although aerobic exercise, particularly swimming, has been shown to alleviate pathological cardiac hypertrophy, its molecular mechanisms remain incompletely understood. In this study, metabolomic and transcriptomic analyses revealed the molecular mechanisms underlying swimming-induced improvement of pathological cardiac hypertrophy. Results showed that swimming training significantly altered the level of isoliensinine in animals. Further studies demonstrated that isoliensinine exerts cardioprotective effects by regulating the expression of Cytochrome C Oxidase Subunit 6A2 (COX6A2), establishing for the first time the critical role of the Isoliensinine-COX6A2 signaling axis in cardiac function regulation. To validate this axis, a pathological cardiac hypertrophy model was constructed in mice through transverse aortic constriction (TAC). Both swimming training and isoliensinine intervention significantly improved cardiac structure and function. In vitro experiments using isoproterenol (ISO)-induced hypertrophy in H9C2 cells further confirmed the essential role of this signaling axis in suppressing pathological hypertrophy and maintaining mitochondrial homeostasis. Our findings demonstrate that swimming mitigates pathological cardiac hypertrophy by enhancing COX6A2 expression by isoliensinine, thereby improving mitochondrial function. This study not only expands the understanding of exercise-mediated mechanisms in pathological cardiac remodeling but also highlights the cardioprotective potential of isoliensinine and COX6A2 as therapeutic targets for preventing and treating heart failure.

molecular biology↗

bioRxiv2025

Bidirectional regulation of glycoprotein nonmetastatic melanoma protein B by β-glucocerebrosidase deficiency in GBA1 isogenic dopaminergic neurons from a patient with Gaucher disease and parkinsonism

Variants in GBA1 are common genetic risk factors for several synucleinopathies. The increased risk has been attributed to the toxic effects of misfolded glucocerebrosidase (GCase) (gain-of-function), and the accumulation of lipid substrates due to reduced enzyme activity (loss-of-function). To delineate GBA1 pathogenicity, an iPSC line was generated from a patient with both type 1 Gaucher disease (GBA1: N370S/N370S; p.N409S/p.N409S) and Parkinson disease (PD). From this line, we created a reverted wild-type (WT) line and a GBA1 knockout (KO) line to eliminate misfolded GCase and intensify lipid accumulation. N370S/N370S and KO dopaminergic neurons (DANs) exhibited decreasing GCase levels and progressive accumulation of lipid substrates compared to WT DANs. Notably, the expression of GPNMB, whose levels correlate with PD risk, was upregulated by the mild lipid accumulation in N370S/N370S DANs but disrupted in KO DANs. These findings refine the loss-of-function mechanism by associating PD risk levels of GPNMB with lipid levels specific to GBA1 risk variants.

neuroscience↗

bioRxiv2025

Speak or shout? Nonverbal vocalizations ensure rapid detection of emotions in vocal communication

Human vocal expressions of emotion can be expressed nonverbally, through vocalizations such as shouts or laughter, or speakers can embed emotional meanings in language by modifying their tone of voice ("prosody"). Is there evidence that nonverbal expressions promote "better" (i.e., more accurate, faster) recognition of emotions than speech, and what is the impact of language experience? Our study investigated these questions using a cross-cultural gating paradigm, in which Chinese and Arab listeners (n=25/group) judged the emotion communicated by acoustic events that varied in duration (200 milliseconds to the full expression) and form (vocalizations or prosody expressed in listeners native, second or foreign language). Accuracy was higher for vocalizations overall, but listeners were markedly more efficient to form stable categorical representations of the speakers emotion from vocalizations (M = 417ms) than native prosody (M = 765ms). Language experience enhanced recognition of emotional prosody expressed by native/ingroup speakers for some listeners (Chinese) but not all (Arab), emphasizing the dynamic interplay of socio-cultural factors and stimulus quality on prosody recognition which occurs over a more sustained time window. Our data show that vocalizations are functionally suited to build robust, rapid impressions of a speakers emotion state unconstrained by the listeners linguistic cultural background.

animal behavior and cognition↗

bioRxiv2025

Treating Myotonic Dystrophy with artificial RNA endonucleases to specifically degrade toxic RNA expansions

Myotonic dystrophy type 1 (DM1), the most common autosomal dominant muscular disorder, is driven by expanded CUG repeats in the 3' UTR of DMPK gene, which sequester RNA-binding proteins and cause aberrant alternative splicing. Despite extensive study, no effective treatment exists, and current care remains limited to symptomatic management. Using a customized dual-color reporter carrying RNA repeats in different lengths, we engineered a new class of programmable artificial enzymes (artificial RNA cleavers, or ARCs) that preferentially degrade the pathogenic repeats both in cells and in a mouse model. We further examined the in vivo efficacy of ARCs by systematically delivering ARCs into the DM1 mouse model with muscle-specific adeno-associated viruses, and validated that ARCs can rescue the muscular pathology and movement ability. The treatment by ARCs showed sustained efficacy, low immunogenicity, and minimal off-target effects in animal model, which are key concerns in clinical translation of gene therapies. Collectively, these findings establish ARCs as a potent and precise RNA-targeting platform with strong clinical potential for the treatment of DM1 and other repeat expansion disorders.

synthetic biology↗

bioRxiv2025

Robust statistical assessment of Oncogenotype to Organotropism translation in xenografted zebrafish

Organotropism results from the functional versatility of metastatic cancer cells to survive and proliferate in diverse microenvironments. This adaptivity can originate in clonal variation of the spreading tumor and is often empowered by epigenetic and molecular reprogramming of cell regulatory circuits. Related to organotropic colonization of metastatic sites are environmentally-sensitive, differential responses of cancer cells to therapeutic attack. Accordingly, understanding the organotropic profile of a cancer and probing the underlying driver mechanisms are of high clinical importance. However, determining systematically the organotropism of one cancer versus the organotropism of another cancer, potentially with the granularity of comparing the same cancer type between patients or tracking the evolution of a cancer in a single patient for the purpose of personalized treatment, has remained very challenging. It requires a host organism that allows observation of the spreading pattern over relatively short experimental times. Moreover, organotropic patterns often tend to be statistically weak and superimposed by experimental variation. Thus, an assay for organotropism must give access to statistical powers that can separate meaningful heterogeneity, i.e., heterogeneity that determines organotropism, from meaningless heterogeneity, i.e., heterogeneity that causes experimental noise. Here we describe an experimental workflow that leverages the physiological properties of zebrafish larvae for an imaging-based assessment of organotropic patterns over a time-frame of 3 days. The workflow incorporates computer vision pipelines to automatically integrate the stochastic spreading behavior of a particular cancer xenograft in tens to hundreds of larvae allowing subtle trends in the colonization of particular organs to emerge above random cell depositions throughout the host organism. We validate our approach with positive control experiments comparing the spreading patterns of a metastatic sarcoma against non-transformed fibroblasts and the spreading patterns of two melanoma cell lines with previously established differences in metastatic propensity. We then show that integration of the spreading pattern of xenografts in 40 - 50 larvae is necessary and sufficient to generate a Fish Metastatic Atlas page that is representative of the organotropism of a particular oncogenotype and experimental condition. Finally, we apply the power of this assay to determine the function of the EWSR1::FLI1 fusion oncogene and its transcriptional target SOX6 as plasticity factors that enhance the adaptive capacity of metastatic Ewing sarcoma.

cancer biology↗

bioRxiv2025

Divergent MIC of Clarithromycin and Azithromycin Against Clinical Isolates of Mycobacterium abscessus Complex

Current treatment guidelines for Mycobacterium abscessus complex (MAB) infections recommend macrolides (clarithromycin/CAM and azithromycin/AZM) as cornerstone therapies, considering them clinically interchangeable without distinction. This study evaluated the comparative in vitro activity of clarithromycin (CAM) and azithromycin (AZM) against 146 clinical isolates of Mycobacterium abscessus complex organisms. MIC distributions revealed significantly higher resistance to AZM (94.5% resistant at [≥]8 g/mL) compared to CAM (77.4% resistant at [≥]8 g/mL), with only 4.8% of isolates susceptible to both drugs. Notably, 26 strains (17.8% of total) showed AZM resistance despite being non-resistant to CAM (MIC <8 g/mL) among 146 clinical isolates. Among the 33 CAM-non-resistant isolates (including susceptible and intermediate strains), 78.8% (26/33) were AZM-resistant, demonstrating frequent discordance in susceptibility profiles. These findings contrast with current treatment guidelines that recommend using CAM and AZM interchangeably without distinction. Subspecies analysis showed three distinct susceptibility profiles: isolates susceptible to both antibiotics (n=3, M. massiliense), isolates resistant to both antibiotics (n=3, M. massiliense), and M. bolletii with CAM-susceptible/AZM-resistant phenotypes (n=2). This differential resistance pattern suggests that while both drugs face substantial resistance challenges, CAM retains meaningful activity against certain strains that are AZM-resistant-particularly in M. bolletii. These findings indicate that AZM and CAM should not be used interchangeably to treat MAB infections and emphasize the need to prioritize CAM over AZM in treatment regimens.

microbiology↗