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Biology subjects

Wang, C.-W.

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

10 recordsLinked to original sources

Sperm-specific fertility factors SMZ-1/2 promote FB-MO biogenesis and MSP filament assembly in C. elegans

In nematode sperm, motility is powered by polymerization of major sperm protein (MSP) into filaments assembled from a specialized organelle (FB-MO), but how filament formation begins is unclear. We identify two sperm-specific PDZ proteins, SMZ-1 and SMZ-2 (SMZ-1/2), that initiate MSP loading into pre-formed membranous organelles in Caenorhabditis elegans. SMZ-1/2 were expressed specifically in spermatogenic germ cells, colocalized with developing FB-MOs from diplotene through spermatid formation, and were redundant for fertility. Loss of SMZ-1/2 abolished MSP filaments, left MOs MSP-negative and morphologically immature, and caused primary spermatocyte arrest. Electron microscopy showed fewer, smaller FB-MOs lacking crystalline FBs, consistent with a defect in assembly initiation rather than late polymerization. SMZ-1/2 cytoplasmic structures were absent in spe-6 casein kinase mutants, placing SMZ-1/2 within a SPE-6-dependent initiation module. These findings identify SMZ-1/2 as PDZ scaffold proteins that initiate MSP assembly and couple kinase signaling to FB-MO biogenesis during nematode spermatogenesis.

genetics↗

Environmental DNA Metabarcoding Effectively Detects Invasive Species, Pests, and Community Changes in Taiwan Rice Fields

Rice fields represent man-made semi-aquatic wetlands primed for invasive pests. Monitoring rice field biodiversity using conventional methods, however, is time-consuming and laborious. Environmental DNA (eDNA) methods can provide a fast and effective means to monitor rice field communities and inform management decisions. Our study provides proof-of-concept of rice field eDNA biodiversity assessments, with a focus on native and non-native pests across cultivation phases. We collected eDNA samples from locations in southern Taiwan during planting and harvesting, employing eDNA metabarcoding (COI) to detect diverse taxonomic groups. We assigned 77 ASVs across all sites to animal taxa, 34 of which were identified to species. Overall, 18 species were designated as native or non-native (83.3% and 16.6%, respectively), including three major rice pests, Chilo suppressalis (native), Coptotermes formosanus (native), and Pomacea canaliculata (non-native). Cultivation status affected overall diversity, with higher species richness during planting compared to harvesting. No significant differences were observed between native and non-native taxa between cultivation phases. Altogether, we detected a complex environment across trophic levels comprised of both native and non-native agricultural pests using limited sampling effort, demonstrating eDNA analysis as an efficient biomonitoring approach in rice agroecosystems with direct applications for pest, invasive species, and vector surveillance within Taiwan.

ecology↗

Dietary bacteria controls C. elegans lipid metabolism through pathways converging at phosphatidylcholine

Dietary factors play a pivotal role in regulating metabolism in both health and disease. Lipid metabolism is particularly important for organismal health and longevity. However, the mechanisms by which dietary factors influence lipid metabolism remain poorly understood. Here, using the nematode C. elegans as a model system, we investigated the influence of distinct bacterial diets on fat metabolism. We found that dietary vitamin B12 activates the S-adenosyl methionine (SAM) and phosphatidylcholine (PC) biosynthetic pathways. This activation leads to elevated levels of PC, which in turn suppresses the expression of the gene fat-7 and modulates lipid droplet dynamics through the regulatory proteins SBP-1/SREBP1 and SEIP-1/SEIPIN, respectively. Additionally, we identified a feedback loop involving SBP-1-mediated regulation of acid sphingomyelinase ASM-3, which enhances the production of phospho-choline and further stimulates PC synthesis. Our localization studies further suggest that ASM-3 may act as a signaling mediator between the intestine and coelomocytes, coordinating their roles in vitamin B12-mediated fat regulation. Overall, our findings shed new light on the complex interplay between diet and metabolic regulation, with a particular emphasis on the central role of phosphatidylcholine. HighlightsO_LIAnimals govern PC level to regulate lipid homeostasis in response to diets C_LIO_LIB12 regulates SAM-PC axis to affect lipogenic genes expression and LD biogenesis C_LIO_LICoelomocytes regulate diets-induced lipid homeostasis through asm-3 C_LIO_LIasm-3 constructs a positive feedback loop to participate in PC metabolism C_LI

cell biology↗

The Vps13-like protein BLTP2 is pro-survival and regulates phosphatidylethanolamine levels in the plasma membrane to maintain its fluidity and function

Lipid transport proteins (LTPs) facilitate nonvesicular lipid exchange between cellular compartments and have critical roles in lipid homeostasis1. A new family of bridge-like LTPs (BLTPs) is thought to form lipid-transporting conduits between organelles2. One, BLTP2, is conserved across species but its function is not known. Here, we show that BLTP2 and its homolog directly regulate plasma membrane (PM) fluidity by increasing the phosphatidylethanolamine (PE) level in the PM. BLTP2 localizes to endoplasmic reticulum (ER)-PM contact sites3 4, 5, suggesting it transports PE from the ER to the PM. We find BLTP2 works in parallel with another pathway that regulates intracellular PE distribution and PM fluidity6, 7. BLTP2 expression correlates with breast cancer aggressiveness8-10. We found BLTP2 facilitates growth of a human cancer cell line and sustains its aggressiveness in an in vivo model of metastasis, suggesting maintenance of PM fluidity by BLTP2 may be critical for tumorigenesis in humans.

cell biology↗

Water-soluble 4-(dimethylaminomethyl)heliomycin exerts greater antitumor effects than parental heliomycin by targeting the tNOX-SIRT1 axis and apoptosis in oral cancer cells

The antibiotic heliomycin (resistomycin), which is generated from Streptomyces resistomycificus, has multiple activities, including anticancer effects. Heliomycin was first described in the 1960s, but its clinical applications have been hindered by extremely low solubility. A series of 4-aminomethyl derivatives of heliomycin were synthesized to increase water solubility; studies showed that they had anti-proliferative effects, but the drug targets remained unknown. In this study, we conducted cellular thermal shift assays (CETSA) and molecular docking simulations to identify and validate that heliomycin and its water-soluble derivative, 4-(dimethylaminomethyl)heliomycin (designated compound 4-dmH) engaged and targeted with sirtuin-1 (SIRT1) in p53-functional SAS and p53-mutated HSC-3 oral cancer cells. We further addressed the cellular outcome of SIRT1 inhibition by these compounds and found that, in addition to SIRT1, the water-soluble 4-dmH preferentially targeted a tumor-associated NADH oxidase (tNOX, ENOX2). The direct binding of 4-dmH to tNOX decreased the oxidation of NADH to NAD+ which diminished NAD+-dependent SIRT1 deacetylase activity, ultimately inducing apoptosis and significant cytotoxicity in both cell types, as opposed to the parental heliomycin-induced autophagy. We also observed that tNOX and SIRT1 were both upregulated in tumor tissues of oral cancer patients compared to adjacent normal tissues, suggesting their clinical relevance. Finally, the better therapeutic efficacy of 4-dmH was confirmed in tumor-bearing mice, which showed greater tNOX and SIRT1 downregulation and tumor volume reduction when treated with 4-dmH compared to heliomycin. Taken together, our in vitro and in vivo findings suggest that the multifaceted properties of water-soluble 4-dmH enable it to offer superior antitumor value compared to parental heliomycin, and indicated that it functions through targeting the tNOX-NAD+-SIRT1 axis to induce apoptosis in oral cancer cells.

cell biology↗

Individual recombinant repeats of MUC16 display variable binding to CA125 antibodies

BACKGROUNDDespite its importance in the clinical management of ovarian cancer, the CA125 biomarker--located on the mucin protein MUC16--is still not completely understood. Questions remain about MUC16s function and structure, specifically the identity and location of the CA125 epitopes. OBJECTIVEThe goal of this study was to characterize the interaction of individual recombinant repeats from the tandem repeat domain of MUC16 with antibodies used in the clinical CA125 II test. METHODSUsing E. coli expression, we isolated nine repeats from the putative antigenic domain of CA125. Amino acid composition of recombinant repeats was confirmed by high-resolution mass spectrometry. We characterized the binding of four antibodies--OC125, M11, "OC125-like," and "M11-like"--to nine recombinant repeats using Western blotting, indirect enzyme-linked immunosorbent assay (ELISA), and localized surface plasmon resonance (SPR) spectroscopy. RESULTSEach recombinant repeat was recognized by a different combination of CA125 antibodies. OC125 and "OC125-like" antibodies did not bind the same set of recombinant repeats, nor did M11 and "M11-like" antibodies. CONCLUSIONSCharacterization of the interactions between MUC16 recombinant repeats and CA125 antibodies will contribute to ongoing efforts to identify the CA125 epitopes and improve our understanding of this important biomarker.

cancer biology↗

BigNeuron: A resource to benchmark and predict best-performing algorithms for automated reconstruction of neuronal morphology

BigNeuron is an open community bench-testing platform combining the expertise of neuroscientists and computer scientists toward the goal of setting open standards for accurate and fast automatic neuron reconstruction. The project gathered a diverse set of image volumes across several species representative of the data obtained in most neuroscience laboratories interested in neuron reconstruction. Here we report generated gold standard manual annotations for a selected subset of the available imaging datasets and quantified reconstruction quality for 35 automatic reconstruction algorithms. Together with image quality features, the data were pooled in an interactive web application that allows users and developers to perform principal component analysis, t-distributed stochastic neighbor embedding, correlation and clustering, visualization of imaging and reconstruction data, and benchmarking of automatic reconstruction algorithms in user-defined data subsets. Our results show that image quality metrics explain most of the variance in the data, followed by neuromorphological features related to neuron size. By benchmarking automatic reconstruction algorithms, we observed that diverse algorithms can provide complementary information toward obtaining accurate results and developed a novel algorithm to iteratively combine methods and generate consensus reconstructions. The consensus trees obtained provide estimates of the neuron structure ground truth that typically outperform single algorithms. Finally, to aid users in predicting the most accurate automatic reconstruction results without manual annotations for comparison, we used support vector machine regression to predict reconstruction quality given an image volume and a set of automatic reconstructions.

bioinformatics↗

The soil microbiome may offer solutions to ginger cultivation

The Taitung region is one of Taiwans main places for ginger agriculture. Due to issues with disease and nutrient, farmers cannot use continuous cropping techniques on ginger, meaning that the ginger industry is constantly searching for new lands. Continuous cropping increases the risk of infection by Pythium myriotylum and Ralstonia solanacearum, which cause soft rot disease and bacterial wilt, respectively. In addition, fertilizer additives cannot recover the soil when using continuous cropping on ginger, even when there is no decrease in trace elements observed in the soil. Although there may be other reasons for the reduction in production, such as soil microbes, we know little about the soil microbiome associated with ginger cultivation. Hence, in this study, we used the bacterial 16S V3-V4 hypervariable region of the 16S ribosomal RNA region to investigate microbe compositions in ginger soil to identify the difference between ginger soil with and without disease. Later, to investigate the influence of the well-known biocontrol agent-B. velezensis and fungicide Etridiazole on soil microbes and ginger productivity, we designed an experiment that collected the soil samples according to the different ginger cultivation periods to examine the microbial community dynamics in the rhizome and bulk soil. We demonstrated that B. velezensis is beneficial to ginger reproduction and suggest that it may influence the plant by adjusting its soil microbial composition. Etridiazole, on the other hand, may have some side effects on the ginger or beneficial bacteria in the soils, inhibiting ginger reproduction.

microbiology↗

Identification of Immunodominant T-lymphocyte Epitope Peptides in HPV 1, 2 and 3 L1 Protein for Novel Cutaneous Wart Vaccine

BackgroundCommon warts and flat warts are caused by the human papillomavirus (HPV). Peak incidence of wart infection occurs in schoolchildren aged 12-16, where prevalence can be as high as 20%. Traditional treatments aimed at destruction of wart tissue have low clearance rates and high recurrence rates. Occasional reports have even shown warts becoming malignant and progressing into verrucous carcinoma. Current licensed HPV vaccines largely target higher-risk oncogenic HPV types, but do not provide coverage of low-risk types associated with warts. To date, little attention has been given to the development of effective, anti-viral wart treatments. ObjectiveThis study aims to identify immunodominant T-lymphocyte epitopes from the L1 major capsid protein of HPV 1, 2 and 3, a foundational step in bioengineering a peptide-based vaccine for warts. MethodsCytotoxic T-cell and helper T-cell epitopes were predicted using an array of immunoinformatic tools against a reference panel of frequently observed MHC-I and MHC-II alleles. Predicted peptides were ranked based on IC50 and IFN-{gamma} Inducer Scores, respectively, and top performing epitopes were synthesized and subjected to in vitro screening by IFN-{gamma} enzyme-linked immunosorbent spot assay (ELISpot). Independent trials were conducted using PBMCs of healthy volunteers. Final chosen peptides were fused with flexible GS linkers in silico to design a novel polypeptide vaccine. ResultsSeven immunodominant peptides screened from 44 predicted peptides were included in the vaccine design, selected to elicit specific immune responses across MHC class I and class II, and across HPV types. Evaluation of the vaccines properties suggest that the vaccine is stable, non-allergenic, and provides near complete global population coverage (>99%). Solubility prediction and rare codon analysis indicate that the DNA sequence encoding the vaccine is suitable for high level expression in Escherichia coli. ConclusionsIn sum, this study demonstrates the potential and lays the framework for the development of a peptide-based vaccine against warts.

immunology↗

Dietary supplementation with PUFAs rescues the eggshell defects caused by seipin mutations in C. elegans

SEIPIN, an ER membrane protein, plays critical roles in lipid droplet (LD) formation and lipid storage. Dysfunction of SEIPIN causes a variety of human diseases, including lipodystrophy, neuropathies, and male and female infertility. However, the cellular and molecular mechanisms of SEIPIN in causing these diseases are poorly understood. To address such mechanisms, we investigated the functional roles of R01B10.6 (seip-1), the sole SEIPIN1 ortholog in C. elegans, using CRISPR/Cas9 gene editing, and transcriptional assays. SEIP-1::mScarlet is widely expressed throughout development in C. elegans. Three full gene deletion mutants, generated by CRISPR/Cas9, displayed penetrant embryonic lethality. EM imaging and the visualization of reporter genes revealed that the lipid-rich permeability barrier, the innermost layer of the C. elegans embryonic eggshell, was defective or missing. Intriguingly, depletion of SEIP-1 revealed a perturbed gene expression pattern for fatty acid biosynthesis enzymes, in agreement with the disrupted permeability barrier formation phenotype of the embryos. Lastly, dietary supplementation of PUFAs rescued the embryonic lethality and defective permeability barrier in the deletion mutants. In sum, our study suggests that SEIP-1 may maternally regulate LD biogenesis and maintain lipid homeostasis to orchestrate the formation of the lipid-rich permeability barrier, which is crucial for eggshell formation and embryogenesis.

cell biology↗