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Wei, Q.

Publications and source records attributed to Wei, Q..

At least 37 records · Page 2Linked to original sources

Non-invasive skin topical delivery of hyaluronan

Hyaluronic acid (HA), a key glycosaminoglycan in the skin extracellular matrix, diminishes with aging, leading to dryness, wrinkles, and loss of elasticity. While subcutaneous HA injection remains the standard treatment, it is invasive and associated with complications. Here, we developed a zwitterionic polymer-based nanogel system (HA/OP) for noninvasive transdermal HA delivery. The nanogels, formed by complexing HA with poly[2-(N-oxide-N,N-diethylamino)ethyl methacrylate] (OP), exhibited pH-responsive behavior, remaining stable at weakly acidic skin surface pH ([~]5) but dissociating in neutral dermal environments. HA/OP nanogels efficiently permeated the stratum corneum via sebum-assisted enrichment and para-corneocyte transport, followed by transcytosis and enhanced paracellular penetration mediated by myosin light-chain kinase (MLCK) upregulation. This enabled deep HA deposition in the dermis and subcutaneous tissue, significantly improving skin hydration and reducing wrinkles in hairless mice without irritation. Our findings present a safe, needle-free strategy for topical HA delivery, addressing a major unmet need in cosmetic and dermatological applications.

bioengineering↗

A Dual-Functional Needle-Based VOC Sensing Platform for Rapid Vegetable Quality Examination

Volatile organic compounds (VOCs) are common constituents of fruits, vegetables, and crops, and are closely associated with their quality attributes, such as firmness, sugar level, ripeness, translucency, and pungency levels. While VOCs are vital for assessing vegetable quality, traditional detection methods, such as Gas Chromatography-Mass Spectrometry (GC-MS) and Proton Transfer Reaction Mass Spectrometry (PTR-MS) are limited by expensive equipment, complex sample preparation, and slow turnaround time. Additionally, the transient nature of VOCs complicates their detection using these methods. Here, we developed a paper-based colorimetric sensor array combined with needles that could induce vegetable VOC release in a minimally invasive fashion and analyze VOCs in situ with a smartphone reader device. The colorimetric sensor array was optimized using sulfur compounds as main targets and classified fourteen different vegetable VOCs, including sulfoxides, sulfides, mercaptans, thiophenes, and aldehydes. By combining principal components analysis (PCA) analysis, the integrated sensor platform proficiently discriminated between four vegetable subtypes originating from two major categories within 2 min of testing time. This rapid and minimally invasive sensing technology holds great promise for conducting field-based vegetable quality monitoring. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=133 SRC="FIGDIR/small/628229v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@12bf541org.highwire.dtl.DTLVardef@f2a809org.highwire.dtl.DTLVardef@f5f5b7org.highwire.dtl.DTLVardef@1d7027f_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

Natural killer cell dysfunction drives keloid pathogenesis

Keloids, characterized by excessive scar tissue resulting from abnormal wound healing, are primarily driven by hyperproliferative fibroblasts and overproduction of extracellular matrix. Although human natural killer (NK) cells are known for their role in inhibiting uncontrolled cell growth through cytokines like IFN-{gamma} and TNF-, they also produce amphiregulin (AREG), which paradoxically promotes cell proliferation and survival. The involvement of NK cells in keloid pathogenesis, however, remains largely unexplored. This study uncovers remarkable functional changes in NK cells within both lesional skin and the blood of keloid patients. In the skin, NK cell-produced IFN-{gamma} plays a pivotal role in limiting keloid progression by inducing fibroblast apoptosis and curbing excessive extracellular matrix production, while NK cell-derived AREG actively opposes these protective effects. Notably, TGF-{beta}-driven fibroblasts in keloid lesions further dampen NK cell IFN-{gamma} production, revealing a complex and dynamic cellular interplay. In the bloodstream of keloid patients, a distinct NK cell subset emerges, marked by elevated interferon-stimulated genes (ISGs) and diminished IFN-{gamma} production, which correlates with increased plasma IFN-{beta} levels. This elevated IFN-{beta} serves as a key initiating factor, driving NK cell exhaustion through impaired mitochondrial function and metabolic disruption. These findings highlight a critical mechanism underlying the functional abnormalities of keloid-associated NK cells and emphasize the influence of both local and systemic factors in shaping NK cell responses in keloid pathogenesis. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/624588v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@7501f4org.highwire.dtl.DTLVardef@1d34de5org.highwire.dtl.DTLVardef@19f1c47org.highwire.dtl.DTLVardef@f98882_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIIn the skin, NK cell-derived IFN-{gamma} is crucial for suppressing keloid fibroblast proliferation and extracellular matrix production. C_LIO_LIAREG from NK cells counteracts the inhibitory effects of IFN-{gamma} on keloid progression. C_LIO_LIIn the blood, elevated IFN-{beta} in keloid patients drives the emergence of ISG+NK cells with reduced IFN-{gamma} production. C_LIO_LIIFN-{beta} induces mitochondrial dysfunction and functional exhaustion in NK cells. C_LI

immunology↗

An immunomechanical checkpoint PYK2 governs monocyte-to-macrophage differentiation in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a fibrotic, stiff tumor microenvironment (TME), where tumor-associated macrophages (TAMs) drive ECM remodeling, progression, and immune evasion. The contribution of mechanical cues to monocyte differentiation into TAMs remains largely unexplored. Here we show that mechanical force is required for monocyte-to-macrophage differentiation. PYK2, as an innovative immunomechanical checkpoint, de facto governs this differentiation process. We demonstrated that PYK2 senses mechanical signals via Piezo1 and integrins, triggering F-actin polymerization and translocating to the nucleus to regulate mechanotransduction and differentiation genes (e.g., ACTR3, RELA). Targeted deletion of PYK2 impairs the differentiation and polarization of monocyte-derived macrophages, reshapes the PDAC microenvironment, and enhances the efficacy of anti-PD-1 immunotherapy. These findings underscore the critical role of mechanical cues in monocyte differentiation and suggest that targeting PYK2 is a promising strategy to modulate TAM function and improve immunotherapy outcomes in patients with PDAC. Statement of significanceThis study identifies PYK2 as an immunomechanical checkpoint that drives monocyte-to-macrophage differentiation in PDAC via Piezo1/integrin-mediated mechanical cues. Targeted deletion of PYK2 reshapes the PDAC microenvironment, and enhances the efficacy of anti-PD-1 immunotherapy, suggesting PYK2 as a promising therapeutic target to overcome immunotherapy resistance.

immunology↗

Generating Biomedical Knowledge Graphs from Knowledge Bases, Registries, and Multiomic Data

As large clinical and multiomics datasets and knowledge resources accumulate, they need to be transformed into computable and actionable information to support automated reasoning. These datasets range from laboratory experiment results to electronic health records (EHRs). Barriers to accessibility and sharing of such datasets include diversity of content, size and privacy. Effective transformation of data into information requires harmonization of stakeholder goals, implementation, enforcement of standards regarding quality and completeness, and availability of resources for maintenance and updates. Systems such as the Biomedical Data Translator leverage knowledge graphs (KGs), structured and machine learning readable knowledge representation, to encode knowledge extracted through inference. We focus here on the transformation of data from multiomics datasets and EHRs into compact knowledge, represented in a KG data structure. We demonstrate this data transformation in the context of the Translator ecosystem, including clinical trials, drug approvals, cancer, wellness, and EHR data. These transformations preserve individual privacy. We provide access to the five resulting KGs through the Translator framework. We show examples of biomedical research questions supported by our KGs, and discuss issues arising from extracting biomedical knowledge from multiomics data.

bioinformatics↗

Nondestructive Seed Genotyping via Microneedle-Based DNA Extraction

Crop breeding plays an essential role in addressing food security by enhancing crop yield, disease resistance, and nutritional value. However, the current crop breeding process faces multiple challenges and limitations, especially in genotypic evaluations. Traditional methods for seed genotyping remain labor-intensive, time-consuming, and cost-prohibitive outside of large-scale breeding programs. Here, we present a handheld microneedle (MN)-based seed DNA extraction platform for rapid, nondestructive, and in-field DNA isolation from crop seeds for instant marker analysis. Using soybean seeds as a case study, we demonstrated the use of polyvinyl alcohol (PVA) MN patches for the successful extraction of DNA from softened soybean seeds. This extraction technology maintained high seed viability, showing germination rates of 82% and 79%, respectively, before and after MN sampling. The quality of MN-extracted DNA was sufficient for various genomic analyses, including PCR, LAMP, and whole genome sequencing. Importantly, this MN patch method also allowed for the identification of specific genetic differences between soybean varieties. Additionally, we designed a 3D-printed extraction device, which enabled multiplexed seed DNA extraction in a microplate format. In the future, this method could be applied at scale and in-field for crop seed DNA extraction and genotyping analysis.

plant biology↗

Automatic detection of seizures within zebrafish larvae epilepsy models using single-channel electroencephalography

Researchers continue to pursue new drugs capable of treating intractable, or drug- resistant, epilepsy as a large number of patients do not see a reduction in the number of seizures from current treatments. To quicken the pace of drug research, zebrafish (Danio rerio) have been utilized as a model organism for testing anticonvulsant drugs before clinical trials. However, the lengthy task of labeling electroencephalography (EEG) data slows the pace of this line of research and limits its full potential. This study investigated the creation of automatic seizure detection algorithms for electroencephalogram data recorded from seizure-induced zebrafish to detect seizure, artifact, and neurotypical events. Four unique seizure detection algorithms were proposed and implemented based on k-nearest neighbor (KNN), support vector machine (SVM), and artificial neural network (ANN) classifiers. These four techniques were tested using the same input features and their results compared. The best-performing algorithm was identified as the Single Stage KNN with an 83.8% accuracy, followed by the Single Stage ANN with an 80.3% accuracy. The results indicate that a single-stage, multiclass classification architecture may be beneficial to automatically labeling epilepsy data, thus enhancing efficiency. Furthermore, the results for the algorithms which separate the multiclass classification into a series of binary classifications suggest that there are advantages in research and clinical settings to implement a detection algorithm that can delineate neurotypical and non-neurotypical data to assist with manual labeling.

bioengineering↗

Conditioned immunological memory: implication for cognition of immune cells

Associative learning refers to the process by which animals or human beings build the new relationship between two stimuli or events, which has been found throughout the animal kingdom. However, no studies have reported the associative learning in cells in the body to date. In the study, we focused on immune cells, as immunological memory is considered as one of the cardinal features of the immune system. As for a classical conditioning procedure, we designed the analogues of ginsenoside Rh1 (e.g., protopanaxadiol and panaxadiol) as the conditioned stimulus (CS) and the mcKLH-Rh1 conjugate as the unconditioned stimulus (US) and determined the CS-US association by detecting the dynamics of anti-Rh1 antibody production in serum. To test the hypothesis that immune cells also have the same associative learning ability as animals or human beings, mice were divided into control and CS group. Based on above CS and US, two groups of mice were subjected to conditioned learning, conditional memory recall, and deconditioning. When we used protopanaxadiol as the CS, the antibody response to Rh1 in the mice of CS group was slower and weaker than the control mice during conditional memory recall. Interestingly, the difference between two groups in antibody response to the immunogen disappeared during deconditioning. When we used panaxadiol as the CS, the antibody response to Rh1 in the mice of two groups was similar with that in studies regarding protopanaxadiol as the CS throughout three experimental phases. These results suggested that immune cells could acquire new association between a hapten analogue and a hapten-protein conjugate after undergoing a classical conditioning. Moreover, the conditioned immunological memory enables immune cells to make a conditioned response of humoral immunosuppression to prevent US induced immune damage. Our findings open a new frontier to explore cognitive functions of cells in the body and contribute to a novel understanding of cellular bioactivities.

immunology↗

Single cell transcriptome profiling reveals pathogenesis of Bullous Pemphigoid

Bullous pemphigoid (BP) triggers profound functional changes in both non-immune and immune cells in the skin and circulation, yet the underlying mechanisms remain elusive. In this study, we conducted single-cell transcriptome analysis on donor-matched lesional and non-lesional skin, as well as blood samples from BP patients. Lesional skin non-immune cells coordinately upregulated metabolism, wound healing, immune activation, and cell migration associated pathways. Skin LAMP3+ DCs derived from cDC2 exhibited higher pro-inflammatory signatures than those from cDC1, and VEGFA+ mast cells driving BP progression, were predominantly from lesional skin. As BP patients transition from active to remission stages, blood B cell function shifts from differentiation and memory formation to heightened type 1 interferon signaling and reduced IL-4 response. Blood CX3CR1+ZNF683+ and LAG3+ exhausted T cells exhibited the highest TCR expansion among clones shared with skin CD8+T cells, suggesting they likely represent BP-reactive cells fueling skin CD8+T cell clonal expansion. Clinical parameters for BP severity correlated positively with blood NK cell IFN-{gamma} production, whereas correlated negatively with NK cell AREG production. In lesional skin, NK cell-keratinocyte interactions exhibited reduced AREG-EGFR and enhanced IFNG-IFNGR1/2 signaling. NK cell-derived AREG mitigates IFN-{gamma}-induced keratinocyte apoptosis, highlighting a crucial balance between AREG and IFN-{gamma} in BP progression. These results reveal significant functional shifts in BP pathology within skin and blood cells and suggest new therapeutic targets for disease management. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=193 SRC="FIGDIR/small/601141v2_ufig1.gif" ALT="Figure 1"> View larger version (77K): org.highwire.dtl.DTLVardef@18517f2org.highwire.dtl.DTLVardef@e743e9org.highwire.dtl.DTLVardef@11b9228org.highwire.dtl.DTLVardef@11884c3_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

A modular toolkit for environmental Rhodococcus, Gordonia, and Nocardia enables complex metabolic manipulation.

Soil-dwelling Actinomycetes are a diverse and ubiquitous component of the global microbiome, but largely lack genetic tools comparable to those available in model species such as E. coli or Pseudomonas putida, posing a fundamental barrier to their characterization and utilization as hosts for biotechnology. To address this, we have developed a modular plasmid assembly framework along with a series of genetic control elements for the previously genetically intractable Gram-positive environmental isolate Rhodococcus ruber C208 and demonstrate conserved functionality in diverse environmental isolates of Rhodococcus, Nocardia and Gordonia. This toolkit encompasses Mycobacteriale origins of replication, broad-host range antibiotic resistance markers, transcriptional and translational control elements, fluorescent reporters, a tetracycline-inducible system, and a counter-selectable marker. We use this toolkit to interrogate the carotenoid biosynthesis pathway in Rhodococcus erythropolis N9T-4, a weakly carotenogenic environmental isolate and engineer higher pathway flux towards the keto-carotenoid canthaxanthin. This work establishes several new genetic tools for environmental Mycobacteriales and provides a synthetic biology framework to support the design of complex genetic circuits in these species. IMPORTANCESoil-dwelling Actinomycetes, particularly the Mycobacteriales, include both diverse new hosts for sustainable biomanufacturing and emerging opportunistic pathogens. Rhodococcus, Gordonia and Nocardia are three abundant genera with particularly flexible metabolisms and untapped potential for natural product discovery. Among these, Rhodococcus ruber C208 was shown to degrade polyethylene, Gordonia paraffinivorans can assimilate carbon from solid hydrocarbons, and Nocardia neocaledoniensis (and many other Nocardia) possesses dual isoprenoid biosynthesis pathways. Many species accumulate high levels of carotenoid pigments, indicative of highly active isoprenoid biosynthesis pathways which may be harnessed for fermentation of terpenes and other commodity isoprenoids. Modular genetic toolkits have proven valuable for both fundamental and applied research in model organisms, but such tools are lacking for most Actinomycetes. Our suite of genetic tools and DNA assembly framework were developed for broad functionality and to facilitate rapid prototyping of genetic constructs in these organisms.

microbiology↗

A Ratiometric Nonfluorescent CRISPR Assay Utilizing Cas12a-Induced Plasmid Supercoil Relaxation

AbstractMost CRISPR-based biosensors rely on labeled reporter molecules and expensive equipment for signal readout. A recent alternative approach quantifies analyte concentration by sizing native {lambda} DNA reporters, providing a simple and label-free solution for ultrasensitive detection. However, this method faces challenges in accurately quantifying size reduction of long DNA reporters via gel electrophoresis due to the sensitivity of DNA band shift to other interferences such as gel distortion. To overcome these limitations, here we developed a simple and robust ratiometric signaling strategy using CRISPR-Cas12a-induced supercoil relaxation of dsDNA plasmid reporters. In the presence of target, we observed that the fraction of supercoiled plasmid DNA decreased, and the amount of relaxed conformation (circular) increased over time. The relative percentage of supercoiled DNA to the relaxed circular DNA was analyzed by gel electrophoresis to generate an intensity-based ratiometric signal for more accurate target concentration quantification. This simple and inexpensive method is [~]100 times more sensitive when compared with the typical fluorescent reporter system. This self-referenced strategy solves the potential application limitations of previously demonstrated DNA sizing-based CRISPR-Dx without compromising the sensitivity. Finally, we demonstrated the applicability of ratiometric sensing strategy using model DNA targets such as AAV and HPV 16, highlighting its feasibility for point-of-use CRISPR-Dx applications. Table of Contents (TOC) O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=118 SRC="FIGDIR/small/570032v2_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@2c81b3org.highwire.dtl.DTLVardef@1f7453aorg.highwire.dtl.DTLVardef@e1eb06org.highwire.dtl.DTLVardef@cf103_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Rapid Adeno-Associated Virus Genome Quantification with Amplification-Free CRISPR-Cas12a

Efficient manufacturing of recombinant Adeno-Associated Viral (rAAV) vectors to meet rising clinical demand remains a major hurdle. One of the most significant challenges is the generation of large amounts of empty capsids without the therapeutic genome. There is no standardized analytical method to accurately quantify the viral genes, and subsequently the empty-to-full ratio, making the manufacturing challenges even more complex. We propose the use of CRISPR diagnostics (CRISPR-Dx) as a robust and rapid approach to determine AAV genome titers. We designed and developed the CRISPR-AAV Evaluation (CRAAVE) assay to maximize sensitivity, minimize time-to-result, and provide a potentially universal design for quantifying multiple transgene constructs encapsidated within different AAV serotypes. We also demonstrate an on-chip CRAAVE assay with lyophilized reagents to minimize end user assay input. The CRAAVE assay was able to detect AAV titers as low as 7e7 vg/mL with high precision (<3% error) in quantifying unknown AAV titers when compared with conventional quantitative PCR (qPCR) method. The assay only requires 30 minutes of assay time, shortening the analytical workflow drastically. Our results suggest CRISPR-Dx could be a promising tool for efficient rAAV genome titer quantification and has the potential to revolutionize biomanufacturing process analytical technology (PAT). Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=183 HEIGHT=200 SRC="FIGDIR/small/567134v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@1bfce18org.highwire.dtl.DTLVardef@17393c9org.highwire.dtl.DTLVardef@eb7c1forg.highwire.dtl.DTLVardef@2203cd_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Enhancing Luciferase Activity and Stability through Generative Modeling of Natural Enzyme Sequences

The availability of natural protein sequences synergized with generative artificial intelligence (AI) provides new paradigms to create enzymes. Although active enzyme variants with numerous mutations have been produced using generative models, their performance often falls short compared to their wild-type counterparts. Additionally, in practical applications, choosing fewer mutations that can rival the efficacy of extensive sequence alterations is usually more advantageous. Pinpointing beneficial single mutations continues to be a formidable task. In this study, using the generative maximum entropy model to analyze Renilla luciferase homologs, and in conjunction with biochemistry experiments, we demonstrated that natural evolutionary information could be used to predictively improve enzyme activity and stability by engineering the active center and protein scaffold, respectively. The success rate of designed single mutants is [~]50% to improve either luciferase activity or stability. These finding highlights natures ingenious approach to evolving proficient enzymes, wherein diverse evolutionary pressures are preferentially applied to distinct regions of the enzyme, ultimately culminating in an overall high performance. We also reveal an evolutionary preference in Renilla luciferase towards emitting blue light that holds advantages in terms of water penetration compared to other light spectrum. Taken together, our approach facilitates navigation through enzyme sequence space and offers effective strategies for computer-aided rational enzyme engineering.

bioinformatics↗

Transcriptional profiling of skin cancer NK cells reveals the elevated glucocorticoid signaling switches their anti-tumor characteristics to a homeostatic feature

Natural killer (NK) cells are potent mediators of anti-tumor immunity, yet their functions are frequently subverted by tumor microenvironment-driven immunosuppression. Here, we dissect the molecular mechanisms underlying NK cell dysfunction in cutaneous malignancies and identify a paradoxical cytokine shift in tumor-associated NK cells-reduced production of IFN-{gamma} and TNF- alongside elevated amphiregulin (AREG), an EGFR ligand linked to tumor progression. Single-cell transcriptomic analysis indicates that this reprogramming correlates with elevated glucocorticoid receptor (GR/NR3C1) pathway activity in tumor-infiltrating NK cells. Functional validation demonstrated that glucocorticoids specifically induce AREG production in NK cells, with tumor-associated prostaglandin E2 (PGE2) augmenting this response. Genetic ablation or pharmacological inhibition of NR3C1 abolished glucocorticoid-driven AREG induction. Moreover, primary GR activation established persistent chromatin accessibility at the AREG locus, sensitizing NK cells to enhanced AREG production upon secondary glucocorticoid exposure. Functionally, AREG counteracts NK cell-mediated tumor apoptosis, while adoptive transfer of AREG-deficient human NK cells significantly suppressed melanoma, cutaneous squamous cell carcinoma (cSCC), and hepatocellular carcinoma growth in NCG mice. These findings establish the GR-AREG axis as a multi-layered therapeutic target for restoring NK cell anti-tumor function. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/557530v3_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1ef982forg.highwire.dtl.DTLVardef@f036a7org.highwire.dtl.DTLVardef@941abborg.highwire.dtl.DTLVardef@1670d23_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Cep290 is cooperatively maintained at basal body by Cep131-Cep162 and Cby-Fam92 modules

Cilia play critical roles in cell signal transduction and organ development. Defects in cilia function result in a variety of genetic disorders. Cep290 is an evolutionarily conserved ciliopathy protein that bridges the ciliary membrane and axoneme at the basal body and plays critical roles in the initiation of ciliogenesis and TZ assembly. How Cep290 is maintained at basal body and whether axonemal and ciliary membrane localized cues converge to determine the localization of Cep290 remain unknown. Here, we report that the Cep131-Cep162 module near the axoneme and the Cby-Fam92 module close to the membrane synergistically control the basal body localization of Cep290 and the subsequent initiation of ciliogenesis. Concurrent deletion of any protein of the Cep131-Cep162 module and of the Cby-Fam92 module leads to a complete loss of Cep290 from basal body and blocks ciliogenesis at its initiation stage. Our results reveal that the first step of ciliogenesis strictly depend on cooperative and retroactive interactions between Cep131-Cep162, Cby-Fam92 and Cep290, which may contribute to the complex pathogenesis of Cep290-related ciliopathies.

cell biology↗

Alstrom Syndrome protein Alms1 is required for maintaining meiotic centriole engagement in spermatocytes of Drosophila

Maintaining proper mother-daughter centriole engagement is crucial for controlling centrosome numbers and ensuring accurate cell division in both mitosis and meiosis. However, the mechanism responsible for this maintenance remains unclear. Here, we report that the Drosophila homolog of human ciliopathy gene Alstrom Syndrome 1 (Alms1) is required for maintaining centriole engagement during spermatocyte meiosis. We demonstrated that deletion of Alms1 results in premature centriole disengagement in prophase of meiosis I, leading to the formation of multipolar spindles and abnormal cell division in Drosophila spermatocytes. Further studies reveal that Alms1 localizes to the proximal centrioles, and functions downstream of cartwheel protein Sas-6 to regulate centriole engagement, and its highly conserved ALMS motif is required for Alms1s function in centriole engagement. Moreover, we show that the centriole size and pericentriolar materials (PCM) have antagonistic roles on maintaining centriole engagement in alms1 mutant flies. Our findings highlight the critical role of Alms1 as a "glue protein" in maintaining mother-daughter centriole pair cohesion, potentially advancing our comprehension of the pathogenesis of Alstrom Syndrome. Significance statementAlstrom syndrome (AS) is a human ciliopathy that results from mutations in the ALMS1 gene inherited in an autosomal recessive manner. Elucidating the roles of ALMS1 and the underlying molecular mechanisms of AS is of paramount importance. In this study, using Drosophila model, we discovered that ALMS1 is localized at the proximal centrioles, and is crucial for the proper centriole engagement, spindle polarity, cell division in spermatocytes. Our findings reveal the new role of ALSM1 in maintaining centriole engagement, and suggest that non-ciliary function of ALMS1 may contribute to the pathogenesis of Alstrom Syndrome, warranting further investigation.

cell biology↗

Thermoplasmonic modulation of cardiomyocytes activity with local temperature read-out

Cardiomyocyte beating rate modulation is required in multiple in vitro assays and it is usually done by electrical or optogenetic methods. In this work, we develop and characterize a light-based strategy to modulate the cardiomyocyte beating rate by near-infrared (NIR) controlled plasmonic stimulation. For this purpose, gold nanorods (GNRs) acting as plasmonic heaters and silica-coated quantum dots (QDs) as nanothermometers are attached to surfaces used for cardiomyocyte cultures, while the cell electrophysiological activity is visualized by monitoring calcium transients via calcium imaging. This system is capable of modulating cardiac activity with near infrared-controllable plasmonic heating while measuring local temperature changes owing to the temperature-dependent fluorescence of silica-coated QDs. Table of Contents (TOC) O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/554091v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@4325fcorg.highwire.dtl.DTLVardef@72c48dorg.highwire.dtl.DTLVardef@c60849org.highwire.dtl.DTLVardef@14a1e27_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

C-type natriuretic peptide improves maternally aged oocytes quality by inhibiting excessive PINK1/Parkin-mediated mitophagy

The overall oocyte quality declines with ageing, and this effect is strongly associated with a higher reactive oxygen species (ROS) level and the resultant oxidative damage. C-type natriuretic peptide (CNP) is a well-characterized physiological meiotic inhibitor that has been successfully used to improve immature oocyte quality during in vitro maturation (IVM). However, the underlying roles of CNP in maternally aged oocytes have not been reported. Here, we found that the age-related reduction in the serum CNP concentration was highly correlated with decreased oocyte quality. Treatment with exogenous CNP promoted follicle growth and ovulation in aged mice and enhanced meiotic competency and fertilization ability. Interestingly, the cytoplasmic maturation of aged oocytes was thoroughly improved by CNP treatment, as assessed by spindle/chromosome morphology and redistribution of organelles (mitochondria, the endoplasmic reticulum [ER], cortical granules [CGs], and the Golgi apparatus). CNP treatment also ameliorated DNA damage and apoptosis caused by ROS accumulation in aged oocytes. Importantly, oocyte RNA-seq revealed that the beneficial effect of CNP on aged oocytes was mediated by restoration of mitochondrial oxidative phosphorylation, eliminating excessive mitophagy. CNP reversed the defective phenotypes in aged oocytes by alleviating oxidative damage and suppressing excessive PINK1/Parkin-mediated mitophagy. Mechanistically, CNP functioned as a cAMP/PKA pathway modulator to decrease PINK1 stability and inhibit Parkin recruitment. In summary, our results demonstrated that CNP supplementation constitutes an alternative therapeutic approach for advanced maternal age-related oocyte deterioration and may improve the overall success rates of clinically assisted reproduction in older women.

developmental biology↗