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Mo, Y.

Publications and source records attributed to Mo, Y..

16 recordsLinked to original sources

sxRaep: A Rapid and Accurate Enzyme Predictor for high-throughput mining of enzymatic sequences

MotivationMetagenomic sequencing generates petabyte-scale sequence datasets that strain both deep learning and alignment based enzyme annotation tools. A lightweight rapid and accurate filter tool is needed to filter and identify enzymatic sequences prior to resource-intensive functional prediction. ResultsWe present sxLaep (Lightweight and Accurate Enzyme Predictor), a resource-efficient framework using lightweight physicochemical features for enzyme pre-screening. On the external validation set, sxLaep completed prediction in only 0.002 s/sequence, which is 22.9-fold faster than Diamond (0.0457 s/sequence). It used 372.16 MB peak memory, corresponding to a 54.4% memory reduction relative to Diamond (815.64 MB). sxLaep achieved an accuracy of 99.34% and the highest recall in remote homology detection, including enzyme candidates missed by alignment-based methods. We further successfully applied sxLaep to a marine metagenomic enzyme-mining workflow, demonstrating its utility for high-throughput discovery from large-scale metagenomic sequences. Availability and ImplementationsxLaep is available as a Python package at https://pypi.org/project/sxlaep and is maintained as an open-source software repository at https://github.com/labxscut/sxLaep. Detailed installation, usage, and Docker deployment instructions are provided in the GitHub repository to support reproducible enzyme prediction and model execution. Contactlcxia@scut.edu.cn

bioinformatics↗

Genomic insights into rapid diversification and adaptive introgression in the earthworm Amynthas aspergillum

How species diversify in highly fragmented landscapes while maintaining genetic connectivity remains a central question in evolutionary biology. The megascolecid earthworm Amynthas aspergillum exemplifies this paradox, showing deeply divergent mitochondrial lineages despite extensive nuclear gene flow across southern China. We conducted whole-genome resequencing across its core distribution in the Guangxi karst region to elucidate the population structure and processes underlying this cytonuclear discordance. Genome-wide analyses identified three genetically distinct groups shaped by fine-scale karst isolation, alongside pervasive historical and contemporary introgression. Demographic modeling revealed rapid diversification during the Late Pleistocene ([~]0.14LJMa) with pronounced fluctuations in effective population size. Although isolation increased inbreeding and mutational load in some lineages, introgression persisted even among deeply divergent mitochondrial clades. Notably, several introgressed regions showed strong signatures of positive selection, including genes involved in mitochondrial function and metabolism.Together, these results demonstrate that gene flow can simultaneously mitigate the genomic costs of isolation and promote functional innovation via adaptive introgression, providing a genomic framework for diversification with gene flow in subterranean invertebrates inhabiting fragmented karst landscapes.

genomics↗

Aberrant splicing of MBD1 reshapes the epigenome to drive convergent myeloerythroid defects in MDS

Myelodysplastic neoplasms (MDS) feature hematopoietic deficits driven in part by transcript splicing abnormalities. Thus far, such disease-driving transcripts have been identified in association with specific splicing factor mutations. However, it remains unclear whether there also exists a set of disease-wide conserved pathological transcripts, which drive MDS independently of mutational status. Here, we characterize an MDS-associated long isoform of MBD1 (MBD1-L) as the first described member of this class of transcripts. Overexpression of MBD1-L in healthy human HSPCs recapitulates archetypal defects of MDS including deficits in erythroid differentiation and reconstitution capacity. These defects arise from an isoform-specific switching of MBD1s binding behavior, refocusing its heterochromatin-promoting activity from methylated to unmethylated CpGs and enacting broad downregulation of CpG-rich promoters as well as secondary epigenetic effects mediated by its downstream target BCOR. Remarkably, we also find that directly reversing abnormal MBD1 splicing in primary human MDS using nanoparticle-encapsulated ASOs enhances erythroid differentiation. Key pointsO_LIGlobal mis-splicing of MBD1 represents a novel gain-of-function epigenetic axis driving erythropoietic and proliferative defects in MDS. C_LIO_LIASO based depletion of pathogenic MBD1 transcripts restores erythroid differentiation, advancing RNA-based therapies for MDS. C_LI

cancer biology↗

Cutaneous suction-mediated transfection in mice for delivery of DNA-encoded vaccines and proteins

An important step to fulfill the functionalities of DNA vaccines and therapeutics is transfection in vivo to produce the encoded antigens or therapeutic proteins. A cutaneous suction-based method has demonstrated effectiveness in many animal models and has been successfully applied in human clinical trials, but has not been extended to mouse models, where numerous disease models, transgenic strains, and murine-specific reagents exist. The current work establishes and optimizes methods for cutaneous suction-mediated DNA transfection in mice. By adapting a smaller cup diameter and smaller injection volume, the challenges of skin hyperelasticity and decreased skin thickness can be effectively addressed, and vaccinating mice with the GLS-5310 SARS-CoV-2 DNA vaccine yielded high levels of binding antibody and T cell responses. Additionally, suction following injection of a novel pVAX1-based expression vector yielded systemic levels of a SEAP transgene. Thus, suction-mediated delivery of nucleic acid-based therapies and vaccines can be a valuable tool for the study in pre-clinical mouse models.

bioengineering↗

MED1 IDR acetylation reorganizes the transcription preinitiation complex, rewires 3D chromatin interactions and reprograms gene expression

With our current appreciation of the complexity of eukaryotic transcription, whose dysregulation drives diseases including cancer, it is becoming apparent that identification of key events coordinating multiple aspects of transcriptional regulation is of special importance. To elucidate how assembly of RNA polymerase II (Pol II) with Mediator complex preinitiation complexes (PICs) and formation of transcription-permissive 3D chromatin organization are coordinated, we studied MED1, a representative subunit of the Mediator complex that acts to establish functional preinitiation complexes (PICs)1 that forms biomolecular condensates through an intrinsically disordered region (IDR) to facilitate transcription2, and is implicated in the function of estrogen receptor (hereafter ER) in ER-positive breast cancer (ER+ BC) cells3,4. We found that MED1 is acetylated at 6 lysines in its IDR and, further, that MCF7 ER+ BC cells in which endogenous MED1 is replaced by an ectopic 6KR (non-acetylatable) mutant (6KR cells) exhibit enhanced cell growth and elevated expression of MED1-dependent genes. These results indicate an enhanced function of 6KR MED1 that may be attributed to two mechanisms: (1) reorganized PIC assembly, as indicated by increased MED1 and Pol II, decreased MED17, and equivalent ER occupancies on chromatin, particularly at active enhancers and promoters; (2) sub-TAD chromatin unfolding, as revealed by HiCAR (Hi-C on accessible regulatory DNA) analyses. Furthermore, in vitro assays demonstrate distinct physio-chemical properties of liquid-liquid phase separation (LLPS) for 6KR versus 6KQ MED1 IDRs, and for non-acetylated versus CBP-acetylated WT MED1 IDR fragments. Related, Pol II CTD heptads are sequestered in 6KR and control WT MED1 IDR condensates, but not 6KQ and CBP-acetylated WT MED1 IDR condensates. These findings, in conjunction with recent reports of PIC structures5-7, indicate that MED1 coordinates reorganization of the PIC machinery and the rewiring of regional chromatin organization through acetylation of its IDR. This study leads to an understanding of how the transition in phase behavior of a transcription cofactor acts as a mechanistic hub integrating linear and spatial chromatin functions to support gene expression, and have potential therapeutic implications for diseases involving MED1/Mediator-mediated transcription control.

molecular biology↗

Regulation of Interstitial Lung Diseases by Pulmonary Endothelial Cells via PLVAP

Withdrawal statementThe authors have withdrawn this manuscript because the preliminary results require further experimental validation and more comprehensive data collection to ensure scientific rigor. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

cell biology↗

JAZF1 is transcriptionally regulated by SOX11 and promotes cardiac fibrosis by PI3K-Akt pathway

BackgroundCardiac fibrosis is a component of all chronic heart diseases. JAZF1 regulates metabolism through various mechanisms; however, its role in cardiac fibrosis remains unclear. We aimed to investigate the role of JAZF1 in cardiac fibrosis. MethodsA rat cardiac fibrosis model was established by administering isoproterenol subcutaneously for 14 days (5 mg/kg/day); an equal volume of saline was administered to the control group. Cardiac fibroblasts (CFs) were treated with TGF-{beta}1 for 48 h to mimic cardiac fibrosis in vitro. ResultsJAZF1 expression at the protein and mRNA levels was enhanced in CFs and cardiac fibrosis tissues. JAZF1 downregulation suppressed CFs proliferation and migration. Western blotting showed that the PI3K/Akt signaling pathway was significantly decreased after JAZF1 knockdown. Further experiments revealed that SOX11 is an important transcription factor whose overexpression and downregulation enhanced and suppressed JAZF1 levels, respectively. Luciferase analysis showed that SOX11 interacted with the JAZF1 promoter. Moreover, SOX11 promoted cardiac fibrosis by regulating JAZF1 expression. ConclusionsJAZF1 was enhanced in cardiac fibrosis tissue and TGF-{beta}-treated CFs. JAZF1 knockdown decreased CFs migration and proliferation, possibly remediated by SOX11 with activation of PI3k/Akt signaling pathways.

cell biology↗

Wheat plant height locus RHT25 encodes a PLATZ transcription factor that interacts with DELLA (RHT1)

Plant height is an important agronomic trait with a significant impact on grain yield, as demonstrated by the positive effect of the REDUCED HEIGHT (RHT) dwarfing alleles (Rht1b) on lodging and harvest index in the "Green Revolution" wheat varieties. However, these gibberellic acid (GA) insensitive alleles also reduce coleoptile length, biomass production, and yield potential in some environments, triggering the search for alternative GA-sensitive dwarfing genes. Here we report the identification, validation and characterization of the gene underlying the GA-sensitive dwarfing locus RHT25 in wheat. This gene, designated as PLATZ-A1 (TraesCS6A02G156600), is expressed mainly in the elongating stem and developing spike and encodes a plant-specific AT-rich sequence- and zinc-binding protein (PLATZ). Natural and induced loss-of-function mutations in PLATZ-A1 reduce plant height and its over-expression increases it, demonstrating that PLATZ-A1 is the causative gene of RHT25. PLATZ-A1 interacts physically and genetically with RHT1 (DELLA), and both genes have stronger effects on plant height in the presence of the wildtype than in the presence of the mutant allele of the other gene. These results suggest that PLATZ1 can modulate the effect of DELLA on wheat plant height. We identified four natural truncation mutations and one promoter insertion in PLATZ-A1 that are more frequent in modern varieties than in landraces, suggesting positive selection during wheat breeding. These mutations can be used to fine-tune wheat plant height and, in combination with other GA-sensitive dwarfing genes, to replace the GA-insensitive Rht1b alleles to search for grain yield improvements beyond those of the Green Revolution varieties. Significance StatementWe have identified and characterized a previously unknown gene controlling plant height in wheat and named it PLATZ1. Mutations in PLATZ1 reduce plant height while its overexpression results in taller plants. PLATZ1 is expressed mainly in elongating stems and developing spikes and interacts physically and genetically with the "Green Revolution" dwarfing gene REDUCED HEIGHT 1 (RHT1). We discovered five natural mutants in the A genome copy of PLATZ1 in common wheat that have been favored during breeding, suggesting an overall positive effect on wheat performance. These mutations can be used to fine-tune wheat plant height and, eventually, to replace the RHT1 dwarfing alleles that impose limitations on planting depth and grain yield potential in some environments.

plant biology↗

Regulation of osteoblast autophagy based on PI3K/AKT/mTOR signaling pathway study on the effect of β-ecdysterone on fracture healing

PurposeTo investigate the effects of {beta}-ecdysterone on fracture healing and the underlying mechanism. MethodsMTT assay was used to detect the cell viability and alkaline phosphatase (ALP) activity was measured using a commercial kit. AO/PI and flow cytometry assays were used to determine the state of apoptosis of osteoblasts. The expression level of RunX2, ATG7 and LC3 was evaluated by qRT-PCR and Western blot assays. X-ray and HE staining were conducted on the fractured femur to evaluate the pathological state. Immunohistochemical assay was used to detect the expression level of Beclin-1 and immunofluorescence assay was used to measure the expression level of LC3 in the fractured femurs. Western blot was utilized to determine the expression level of PI3K, p-AKT1, AKT1, p-mTOR, mTOR, p-p70S6K, and p70S6K. ResultsThe ALP activity and expression of RunX2 in fractured osteoblasts were significantly suppressed by 3-methyladenine and elevated by rapamycin, 60, and 80 M {beta}-ecdysterone. The apoptotic state of fractured osteoblasts was enhanced by 3-methyladenine and alleviated by rapamycin, 60, and 80 M {beta}-ecdysterone. The state of autophagy both in fractured osteoblasts and femurs was inhibited by 3-methyladenine and facilitated by rapamycin and {beta}-ecdysterone. Compared to control, Garrett score in 3-methyladenine group was significantly decreased and promoted in rapamycin and {beta}-ecdysterone groups, accompanied by ameliorated pathological state. Lastly, the PI3K/AKT/mTOR pathway both in fractured osteoblasts and femurs was activated by 3-methyladenine and inhibited by rapamycin and {beta}-ecdysterone. Conclusion{beta}-ecdysterone might facilitate fracture healing by activating autophagy through suppressing PI3K/AKT/mTOR signal pathway.

animal behavior and cognition↗

Structured illumination microscopy artifacts caused by illumination scattering

Despite its wide application in live-cell super-resolution (SR) imaging, structured illumination microscopy (SIM) suffers from aberrations caused by various sources. Although artifacts generated from inaccurate reconstruction parameter estimation and noise amplification can be minimized, aberrations due to the scattering of excitation light on samples have rarely been investigated. In this paper, by simulating multiple subcellular structure with the distinct refractive index (RI) from water, we study how different thicknesses of this subcellular structure scatter incident light on its optical path of SIM excitation. Because aberrant interference light aggravates with the increase in sample thickness, the reconstruction of the 2D-SIM SR image degraded with the change of focus along the axial axis. Therefore, this work may guide the future development of algorithms to suppress SIM artifacts caused by scattering in thick samples.

biophysics↗

Quantitative Control of Noise in Mammalian Gene Expression by Dynamic Histone Regulations

Fluctuation ( noise) in gene expression is critical for mammalian cellular processes. Numerous mechanisms contribute to its origins, yet large noises induced by single transcriptional activator species remain to be experimentally understood. Here, we combined the dynamic regulation of transcriptional activator binding, histone regulator inhibitors, and single-cell quantification of chromatin accessibility, mRNA, and protein to probe putative mechanisms. Using a light-induced expression system, we show that the transcriptional activator forms a positive feedback loop with histone acetyltransferases CBP/p300. It generates epigenetic bistability in H3K27ac, which contributes to large noise. Disable of the positive feedback loop by CBP/p300 and HDAC4/5 inhibitors also reduces heterogeneity in endogenous genes, suggesting a universal mechanism. We showed that the noise was reduced by pulse-wide modulation of transcriptional activator binding due to alternating the system between high and low monostable states. Our findings could provide a mechanism-based approach to modulate noise in synthetic and endogenous gene expressions.

molecular biology↗

An Engineered Genetic Circuit for Lactose Intolerance Alleviation Coupled with Gut Microbiota Recovery

BackgroundLactose malabsorption occurs in around 68% of the world populations, causing lactose intolerance (LI) symptoms such as abdominal pain, bloating and diarrhoea. To alleviate LI, previous studies mainly focused on strengthening intestinal {beta}-galactosidase activity but neglected the inconspicuous colon pH drop caused by gut microbes fermentation on non-hydrolysed lactose. The colon pH drop will reduce intestinal {beta}-galactosidase activity and influence the intestinal homeostasis. ResultsHere, we synthesized a tri-stable-switch circuit equipped with high {beta}-galactosidase activity and pH rescue ability. This circuit can switch in functionality between expression of {beta}-galactosidase and expression of l-lactate dehydrogenase in respond to intestinal lactose signal and intestinal pH signal. We confirmed the circuit functionality was efficient using 12-hrs in vitro culture at a range of pH levels, as well as 6-hrs in vivo simulations in mice colon. Moreover, another 21-days mice trial indicated that this circuit can recover lactose-effected gut microbiota of mice to the status (enterotypes) similar to that of mice without lactose intake. ConclusionsTaken together, the tri-stable-switch circuit can serve as a promising prototype for LI symptoms relief, especially by flexibly adapting to environmental variation, stabilizing colon pH and restoring gut microbiota.

bioengineering↗

Selective Activation of TASK-3-containing K+ Channels Reveals Their Therapeutic Potentials in Analgesia

The paucity of selective agonists for TASK-3, a member of two-pore domain K+ (K2P) channels, has contributed to our limited understanding of its biological functions. By targeting a novel druggable transmembrane cavity using a structure-based drug design approach, we discovered a biguanide compound, CHET3, as a highly selective allosteric activator for TASK-3-containing K2P channels, including TASK-3 homomer and TASK-3/TASK-1 heteromer. CHET3 displayed unexpectedly potent analgesic effects in vivo in a variety of acute and chronic pain models in rodents that could be abolished by pharmacology or genetic ablation of TASK-3. We further found that TASK-3-containing channels anatomically define a unique subset population of small-sized, TRPM8, TRPV1 or tyrosine hydroxylase-positive nociceptive sensory neurons and functionally regulate their membrane excitability, supporting CHET3 analgesia in thermal hyperalgesia and mechanical allodynia under chronic pain. Overall, our proof-of-concept study reveals TASK-3-containing K2P channels as a novel druggable target for treating pain.\n\nOne Sentence SummaryIdentification of a novel drug target and its new hit compounds for developing new-generation non-opioid analgesics.

pharmacology and toxicology↗

Quantifying antibiotic impact on within-host dynamics of extended-spectrum beta-lactamase resistance in hospitalized patients

Antibiotic exposure can perturb the human gut microbiome and cause changes in the within-host abundance of the genetic determinants of drug-resistance in bacteria. Such within-host dynamics are expected to play an important role in mediating the relationship between antibiotic use and persistence of drug-resistance within a host and its prevalence within a population. Developing a quantitative representation of these within-host dynamics is an important step towards a detailed mechanistic understanding of the population-level processes by which antibiotics select for resistance. Here we study extended-spectrum beta-lactamase (ESBL) producing organisms of the Enterobacteriaceae bacterial family. These have been identified as a global public health priority and are resistant to most first-line antibiotics for treatment of Enterobacteriaceae infections. We analyse data from 833 rectal swabs from a prospective longitudinal study in three European countries including 133 ESBL-positive hospitalised patients. Quantitative polymerase chain reaction was used to quantify the abundance of the CTX-M gene family - the most wide-spread ESBL gene family - and the 16S rRNA gene as a proxy for bacterial load. We find strong dynamic heterogeneity in CTX-M abundance that is largely explained by the variable nature of the swab sampling. Using information on time-varying antibiotic treatments, we develop a dynamic Bayesian model to decompose the serial data into observational variation and ecological signal and to quantify the potentially causal antibiotic effects. We find an association of treatment with cefuroxime or ceftriaxone with increased CTX-M abundance (approximately 21% and 10% daily increase, respectively), while treatment with meropenem or piperacillin-tazobactam is associated with decreased CTX-M (approximately 8% daily decrease for both). Despite a potential risk for indirect selection, oral ciprofloxacin is also associated with decreasing CTX-M (approximately 8% decrease per day). Using our dynamic model to make forward stochastic simulations of CTX-M dynamics, we generate testable predictions about antibiotic impacts on duration of carriage. We find that a typical course of cefuroxime or ceftriaxone is expected to more than double a patients carriage duration of CTX-M. A typical course of piperacillin-tazobactam or of meropenem - both options to treat hospital acquired infections (HAI) like pneumonia - would reduce CTX-M carriage time relative to ceftriaxone plus amikacin (also an option to treat HAIs) by about 70%. While most antibiotics showed little association with changes in total bacterial abundance, meropenem and piperacillin-tazobactam were associated with decrease in 16S rRNA abundance (3% and 4% daily decrease, respectively). Our study quantifies antibiotic impacts on within-host resistance abundance and resistance carriage, and informs our understanding of how changes in patterns of antibiotic use will affect the prevalence of resistance. This work also provides an analytical framework that can be used more generally to quantify the antibiotic treatment effects on within-host dynamics of determinants of antibiotic resistance using clinical data.

epidemiology↗

JNK-IN-8, a c-Jun N-terminal kinase inhibitor, improves functional recovery through suppressing neuroinflammation in ischemic stroke

c-Jun N-terminal kinase (JNK), a mitogen activated protein kinase, is activated in ischemia brain injury and plays an important role in cerebral ischemic injury. Emerging studies demonstrated that JNK-IN-8 (a specific JNK inhibitor) regulates traumatic brain injury through controlling neuronal apoptosis and inflammation. However, the role of JNK-IN-8 in ischemic stroke and the underlying mechanisms of JNK-IN-8 involving neuroprotection remain poorly understood. In the present study, male rats were subjected to tMCAO (transient middle cerebral artery occlusion) followed by treatment with JNK-IN-8, and then the modified improved neurological function score (mNSS), the Foot-fault test and the level of inflammatory cytokines (IL-1{beta}, IL-6 and TNF-) were assessed. We found that JNK-IN-8-treated rats with MCAO exerted a significant improvement in spatial learning as measured by the improved mNSS, and showed sensorimotor functional recovery as measured by the Foot-fault test. JNK-IN-8 also exerted anti-inflammatory effects as indicated by decreased activation of microglia and the decreased expresson of IL-6, IL-1{beta} and TNF-. Furthermore, JNK-IN-8 suppressed the activation of JNK and subsequent activation of NF-{kappa}B signaling as indicated by the decreased level of phosphorylated JNK (p-JNK) and p65. These data suggest that JNK-IN-8 suppressed neuroinflammation and improved neurological function by inhibiting JNK/NF-{kappa}B pathway after ischemic brain injury, thus offering a new target for prevention of ischemic brain injury.

cancer biology↗

Incidental identification of maternal malignancies in two Asian women underwent noninvasive prenatal test

Noninvasive prenatal test (NIPT) has been widely used as a screening test for trisomy 13, 18 and 21 worldwide. Recently, coexistence of maternal malignancy and pregnancy has drawn increasing attention in NIPT studies. Malignancy in pregnant women potentially affected NIPT results, which may cause false positive results or failed tests. However, no such case has ever been reported in Asian population. In this study, for the first time, we reported a stage III dysgerminoma and advanced gastric cancer during pregnancy accidentally identified during NIPT tests. These two women showed aberrant chromosome aneuploidies in NIPT results and concordant pattern of genome disruption found in tumor samples. The findings in this study further validate the effect of maternal malignancy on NIPT results and strengthen the possibility of detecting malignant tumors through NIPT in the future.

cancer biology↗