Biology subjects

Wang, M.-C.

Publications and source records attributed to Wang, M.-C..

6 recordsLinked to original sources

bioRxiv2025

CRISPR/Cas14a Combined with RPA for Visual Detection of Marek's Disease Virus

Mareks disease (MD), a highly contagious avian immunosuppressive disorder caused by the -herpesvirus MDV-1, poses a significant threat to poultry health. The development of rapid visual detection methods capable of distinguishing epidemic MDV-1 strains from vaccine strains is crucial for early disease warning, vaccine efficacy evaluation, and precise disease control. We developed a novel isothermal detection system that integrates recombinase polymerase amplification (RPA) with CRISPR/Cas14a technology for the visual identification of epidemic MDV-1 strains. This method operates at a constant temperature of 37{degrees}C and allows for either real-time analysis or endpoint visual readout without the need for complex instrumentation. Our results showed no cross-reactivity with Newcastle disease virus (NDV), infectious bursal disease virus (IBDV), MDV-1 vaccine strains, or herpesvirus of turkeys (HVT). Plasmid DNA standards were used to determine the sensitivity of the assay and the detection limit was 24.6 copies/L. Clinical evaluation using 24 field samples confirmed that the method successfully identified all MDV-positive cases, demonstrating its diagnostic reliability. In conclusion, we have developed a rapid, instrument-free, and highly specific nucleic acid detection platform for MDV-1 by combining the sensitivity of RPA with the specificity of CRISPR/Cas14a technology, offering promising potential for field-based diagnostics and disease surveillance. IMPORTANCEMareks disease virus (MDV-1) is a highly contagious and economically important avian pathogen. Existing diagnostic methods are unable to reliably distinguish between epidemic and vaccine strains in field settings, which hampers effective surveillance and evaluation of vaccination programs. To address this challenge, we developed a portable isothermal detection assay that combines recombinase polymerase amplification (RPA) with CRISPR/Cas14a technology. This approach enables highly sensitive (24.6 copies/L) and specific visual detection of epidemic MDV-1 strains without cross-reactivity with vaccine strains or related viruses. The assay demonstrated 100% agreement with reference methods when validated using clinical samples. As a cost-effective and instrument-free method, it offers a practical solution for rapid on-site diagnosis, facilitating enhanced outbreak control and improved poultry health management globally.

molecular biology↗

bioRxiv2024

A mutation in vesicular acetylcholine transporter increases tubulin acetylation compromising axonal transport

Kinesin-3 UNC-104(KIF1A) is the major anterograde axonal transporter of synaptic vesicles and is expressed pan-neuronally. Genetic defects in this molecular motor are linked to KIF1A-associated neurological disorders (KAND) encompassing Charcot-Marie-Tooth (CMT) disease and hereditary spastic paraplegia (HSP). From a candidate screen for genes causing neurotransmission defects in C. elegans and simultaneously affecting post-translational modification of tubulin, we identified allele unc-17(e245) significantly elevating tubulin acetylation in vitro and in vivo. UNC-17 encodes for a VAChT (vesicle acetylcholine transporter) and its human ortholog SLC18A3 is implicated in Alzheimers and Huntingtons disease. To exclude secondary effects of the unc-17 mutation, we tracked UNC-104 and RAB-3 motility in the non-cholinergic ALM neuron. With upregulated tubulin acetylation in ALM (anterior lateral microtubule) neurons in unc-17(e245) strains (visualized by immunostaining), motility of both, motor and its cargo, is significantly compromised. However, motility of UNC-104 improves when knocking down alpha-tubulin acetyltransferase MEC-17(ATAT1) in unc-17(e245) strains and, conversely, is negatively affected when overexpressing MEC-17 in wild type animals. UNC-17 and UNC-104 are co-expressed and colocalize in cholinergic head neurons, suggesting a functional motor-cargo relationship. Strikingly, mec-17 knockdown significantly enhances their colocalization, while unc-17 knockdown reduces UNC-104/MEC-17 colocalization in ALM neurons. Direct interactions were confirmed by bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (Co-IP): MEC-17 depletion strengthens UNC-104/UNC-17 association and stabilizes the motor-cargo complex, whereas unc-17 knockdown attenuates UNC-104/MEC-17 interactions, as evidenced by diminished Co-IP signals. We propose that unc-17 knock-down releases MEC-17 from the transport complex, thereby enhancing its tubulin acetyltransferase activity. This elevated acetylation may disrupt motor motility, ultimately impairing synaptic vesicle trafficking. This dynamic interplay, modulated by tubulin acetylation, highlights a regulatory axis involving UNC-104, UNC-17, and MEC-17 across cholinergic and glutamatergic neurons, offering new insights into axonal transport defects relevant to KIF1A-associated neurological disorder (KAND).

cell biology↗

bioRxiv2023

System Neglect and the Neurocomputational Substrates for Over- and Underreactions to Change

AO_SCPLOWBSTRACTC_SCPLOWThe world constantly changes, with the underlying state of the world shifting from one regime to another. The ability to detect a regime shift, such as the onset of a pandemic or the end of a recession, significantly impacts individual decisions as well as governmental policies. However, determining whether a regime has changed is usually not obvious, as signals are noisy and reflective of the volatility of the environment. We designed an fMRI paradigm that examines a stylized regime-shift detection task. Human participants showed systematic over- and underreaction: Overreaction was most commonly seen when signals were noisy but when environments were stable and change is possible but unlikely. By contrast, underreaction was observed when signals were precise but when environments were unstable and hence change was more likely. These behavioral signatures are consistent with the system-neglect computational hypothesis, which posits that sensitivity or lack thereof to system parameters (noise and volatility) is central to these behavioral biases. Guided by this computational framework, we found that individual subjects sensitivity to system parameters were represented by two distinct brain networks. Whereas a frontoparietal network selectively represented individuals sensitivity to signal noise but not environment volatility, the ventromedial prefrontal cortex (vmPFC) showed the opposite pattern. Further, these two networks were involved in different aspects of regime-shift computations: while vmPFC correlated with subjects beliefs about change, the frontoparietal network represented the strength of evidence in favor of regime shifts. Together, these results suggest that regime-shift detection recruits belief-updating and evidence-evaluation networks and that under- and overreactions arise from how sensitive these networks are to the system parameters. SO_SCPLOWIGNIFICANCEC_SCPLOW SO_SCPLOWTATEMENTC_SCPLOWJudging whether the world has changed, from the onset of a market boom to the end of a pandemic, is ubiquitous. The ability to detect regime shifts not only impacts individual decisions but also governmental policies. However, these judgments are hard to make because the signals we receive are noisy and reflective of the volatility of the environment. We find that people overreact to changes when they receive noisy signals in stable environments, but underreact when facing precise signals in unstable environments. Under- and overreactions can be read out by distinct brain networks according to their sensitivity in responding to different environmental parameters that impact regime changes. This suggests that parameter selectivity at the network level guides regime-shift detection.

neuroscience↗

bioRxiv2023

Single worm long read sequencing reveals genome diversity in free-living nematodes

Obtaining sufficient genetic material from a limited biological source is currently the primary operational bottleneck in studies investigating biodiversity and genome evolution. In this study, we employed multiple displacement amplification (MDA) and Smartseq2 to amplify nanograms of genomic DNA and mRNA, respectively from individual Caenorhabditis elegans. Although reduced genome coverage was observed in repetitive regions, we produced assemblies covering 98% of the reference genome using long-read sequences generated with Oxford Nanopore Technologies (ONT). Annotation with the sequenced transcriptome coupled with the available assembly revealed that gene predictions were more accurate, complete and contained far fewer false positives than de novo transcriptome assembly approaches. We sampled and sequenced the genomes and transcriptomes of 13 nematodes from Dorylaimia, Enoplia, and early-branching species in Chromadoria. These free-living species had larger genome sizes, ranging from 147-792 Mb, compared to those of the parasitic lifestyle. Nine mitogenomes were fully assembled and displaying a complete lack of synteny to other species. Phylogenomic analyses based on the new annotations revealed strong support for Enoplia as sister to the rest of Nematoda. Our result demonstrates the robustness of MDA in combination with ONT, paving the way for the study of genome diversity in the phylum Nematoda and beyond.

genomics↗

bioRxiv2020

Impact of urolithiasis and hydronephrosis on acute kidney injury in patients with urinary tract infection

BackgroundUrolithiasis is a common cause of urinary tract obstruction and urinary tract infection (UTI). This study aimed to identify whether urolithiasis with or without hydronephrosis has an impact on acute kidney injury (AKI) in patients with UTI. Methods and findingsThis retrospective study enrolled hospitalized UTI patients who underwent imaging in an acute care setting from January 2006 to April 2019. Of the 1113 participants enrolled, 191 (17.2%) had urolithiasis and 76 (6.8%) had ureteral stone complicated with hydronephrosis. Multivariate logistic regression analysis showed that in UTI patients with urolithiasis, the presence of ureteral stone with concomitant hydronephrosis was an independent risk factor for AKI (odds ratio [OR] 2.345, 95% confidence interval [CI] 1.128-4.876, P = 0.023). In addition, urolithiasis was associated with an increased risk for AKI (OR 2.484, 95% CI 1.398-4.415, P = 0.002) in UTI patients without hydronephrosis. ConclusionThe presence of ureteral stone with hydronephrosis increases the risk for AKI of UTI patients with urolithiasis, and urolithiasis remains a risk factor of AKI in UTI patients without hydronephrosis.

pathology↗

bioRxiv2020

Efficient replacement of long DNA fragments via non-homologous end joining at non-doding regions

Genomic DNA replacement for achieving sophisticated genetic manipulation is implemented currently through homogenous recombination/homology-dependent repair (HR/HDR). Here we report an efficient DNA fragment replacement method that is mediated by non-homologous end joining (NHEJ)-dependent DNA repair at two sites of CRISPR/Cas9-induced double-strand breaks at non-coding genomic regions flanking the exons of targeted genes. We demonstrated this method by generating three conditional alleles and two reporter lines of zebrafish. Functional assays of the conditional alleles proved that the genomic sequence between two inserted loxP sites was deleted by the Cre recombinase, and the phenotype after Cre-induced excision was comparable to previously reported mutants or morphants. Furthermore, combining double-fluorescence expression donor vectors, we showed that the efficiency of this NHEJ-mediated DNA replacement was around 3 times larger than that of HR/HDR-mediated approach. Our method provides a feasible strategy for genomic DNA replacement in zebrafish, which can be applicable for other organisms as well.

genetics↗