Wang C et al. (2009) Annu Rev Genet "The role of mitochondria in apoptosis*."

Youle RJ, Wang C

[Annu Rev Genet, 2009]

Mitochondria play key roles in activating apoptosis in mammalian cells. Bcl-2 family members regulate the release of proteins from the space between the mitochondrial inner and outer membrane that, once in the cytosol, activate caspase proteases that dismantle cells and signal efficient phagocytosis of cell corpses. Here we review the extensive literature on proteins released from the intermembrane space and consider genetic evidence for and against their roles in apoptosis activation. We also compare and contrast apoptosis pathways in Caenorhabditis elegans, Drosophila melanogaster, and mammals that indicate major mysteries remaining to be solved.

Wang C et al. (2019) EMBO Rep "Sex-specific pheromone responses in Caenorhabditis elegans."

Hobert O, Wang C

[EMBO Rep, 2019]

Wang C et al. (2019) Biomicrofluidics "A novel wide-range microfluidic dilution device for drug screening."

Tian Z, Chen X, Zhao X, Chen L, Zhao S, Qin S, Wang C

[Biomicrofluidics, 2019]

Microfluidic dilution chip is a crucial approach to perform gradient dilution of experimental samples in many biological investigations. In this study, we developed two serial wide-range dilution chips with dilution rates of 1:1 and 1:4 on the basis of the microfluidic oscillator by designing a series chamber, which was similar to a series circuit. The size of this chamber was adjusted and mixed with the neighboring air chamber to form dilution rates by oscillatory methods. We applied this microfluidic oscillator to estimate cellular kinetics and perform an acute oxidative stress test on <i>Caenorhabditis elegans</i> (<i>C. elegans</i>) in order to further validate their effectiveness. We estimated the kinetic parameters of -galactosidase, the biocatalyst responsible for the hydrolysis of lactose, and found out that <i>K</i>_m was 602+/-73<i></i>M and <i>k</i>_cat was 72+/-12/s. In addition, our result of the study on acute oxidative stress of <i>C. elegans</i> using this novel chip was consistent with the result using 96-well plates. Overall, we believe that this novel chip can be applied to enzymatic reaction kinetics to evaluate accurately drug screening in bio-nematode models such as <i>C. elegans</i>. In summary, we have provided a novel microfluidic dilution chip that can form a wide range of sample concentration gradients. Our chip may facilitate drug screening, drug toxicology, and environmental toxicology.

Wang C et al. (2014) Nat Methods "Multiplexed aberration measurement for deep tissue imaging in vivo."

Kim DS, Wang C, Tan Z, Kerlin A, Sun W, Milkie DE, Liu R, Ji N, Chen TW

[Nat Methods, 2014]

We describe an adaptive optics method that modulates the intensity or phase of light rays at multiple pupil segments in parallel to determine the sample-induced aberration. Applicable to fluorescent protein-labeled structures of arbitrary complexity, it allowed us to obtain diffraction-limited resolution in various samples in vivo. For the strongly scattering mouse brain, a single aberration correction improved structural and functional imaging of fine neuronal processes over a large imaging volume.

Wang C et al. (2021) Cytometry A "Innovative fluorescent probes for in vivo visualization of biomolecules in living Caenorhabditis elegans."

Zhu Y, Zhang H, Wang C, Xia C

[Cytometry A, 2021]

Caenorhabditis elegans (C. elegans) as a well-established multicellular model organism has been widely used in the biological field for half a century. Its numerous advantages including small body size, rapid life cycle, high-reproductive rate, well-defined anatomy, and conserved genome, has made C. elegans one of the most successful multicellular model organisms. Discoveries obtained from the C. elegans model have made great contributions to research fields such as development, aging, biophysics, immunology, and neuroscience. Because of its transparent body and giant cell size, C. elegans is also an ideal subject for high resolution and high-throughput optical imaging and analysis. During the past decade, great advances have been made to develop biomolecule-targeting techniques for noninvasive optical imaging. These novel technologies expanded the toolbox for qualitative and quantitative analysis of biomolecules in C. elegans. In this review, we summarize recently developed fluorescent probes or labeling techniques for visualizing biomolecules at the cellular, subcellular or molecular scale by using C. elegans as the major model organism or designed specifically for the applications in C. elegans. Combining the technological advantages of the C. elegans model with the novel fluorescent labeling techniques will provide new horizons for high-efficiency quantitative optical analysis in live organisms.

Wang C et al. (2022) Aging Cell "GPCR signaling regulates severe stress-induced organismic death in Caenorhabditis elegans."

Wang C, Long Y, Wang B, Zhang C, Ma DK

[Aging Cell, 2022]

How an organism dies is a fundamental yet poorly understood question in biology. An organism can die of many causes, including stress-induced phenoptosis, also defined as organismic death that is regulated by its genome-encoded programs. The mechanism of stress-induced phenoptosis is still largely unknown. Here, we show that transient but severe freezing-thaw stress (FTS) in Caenorhabditis elegans induces rapid and robust phenoptosis that is regulated by G-protein coupled receptor (GPCR) signaling. RNAi screens identify the GPCR-encoding fshr-1 in mediating transcriptional responses to FTS. FSHR-1 increases ligand interaction upon FTS and activates a cyclic AMP-PKA cascade leading to a genetic program to promote organismic death under severe stress. FSHR-1/GPCR signaling up-regulates the bZIP-type transcription factor ZIP-10, linking FTS to expression of genes involved in lipid remodeling, proteostasis, and aging. A mathematical model suggests how genes may promote organismic death under severe stress conditions, potentially benefiting growth of the clonal population with individuals less stressed and more reproductively privileged. Our studies reveal the roles of FSHR-1/GPCR-mediated signaling in stress-induced gene expression and phenoptosis in C. elegans, providing empirical new insights into mechanisms of stress-induced phenoptosis with evolutionary implications.

Wang, C. et al. (2019) International Worm Meeting "Expression and functional studies of the DM-domain transcription factors reveal novel sexual dimorphisms."

WANG, C., Hobert, O.

[International Worm Meeting, 2019]

Understanding structural and functional differences in the brains of females and males is fundamental for explaining sexually dimorphic animal behaviors. Despite variations in sexual differentiation pathways among species, a common theme adapted across phyla is the use of the DM (Drosophila doublesex/C. elegans mab-3 domain) family transcription factors, making them ideal candidate genes for studying mechanisms behind sexual dimorphisms. The DM family genes are expanded extensively in various species and have been implicated in regulating the development of somatic gonads and differentiation of neurons. The C. elegans genome encodes 11 DM genes, two of which conserved in humans. Only a small subset of these genes have been characterized in detail before. By CRISPR/Cas9-mediated gfp tagging of all 11 endogenous DM genes, we discovered novel sexual dimorphisms in the C. elegans nervous system. In contrast to previously reported sexually dimorphic expression of DM genes in a few sensory neurons mostly born only in males and not hermaphrodites (somatic females), our CRISPR lines reveal that of the 294 neurons that are lineally and anatomically generated in both sexes (sex-shared), about 40% of them (or 24% of sex-shared neuron classes) express a DM gene exclusively in males. Importantly, these dimorphic neurons include not only sensory, but also inter- and motor neurons. Further, based on known connectome studies, some of these neurons generate sexually dimorphic synaptic connections with other sex-shared neurons, indicating potential roles of DM genes in regulating sexual dimorphisms on a synaptic level. Mutant analysis showed that mab-3, one of the DM genes, contributes to sexually dimorphic locomotory behaviors. Taken together, completion of this work using the conserved DM genes for studying neuronal sexual dimorphisms will shed light on our understanding on sex differences in the nervous system.

Wang C et al. (2022) Front Pharmacol "Using Caenorhabditis elegans to Model Therapeutic Interventions of Neurodegenerative Diseases Targeting Microbe-Host Interactions."

Zheng C, Wang C

[Front Pharmacol, 2022]

Emerging evidence from both clinical studies and animal models indicates the importance of the interaction between the gut microbiome and the brain in the pathogenesis of neurodegenerative diseases (NDs). Although how microbes modulate neurodegeneration is still mostly unclear, recent studies have started to probe into the mechanisms for the communication between microbes and hosts in NDs. In this review, we highlight the advantages of using Caenorhabditis elegans (C. elegans) to disentangle the microbe-host interaction that regulates neurodegeneration. We summarize the microbial pro- and anti-neurodegenerative factors identified using the C. elegans ND models and the effects of many are confirmed in mouse models. Specifically, we focused on the role of bacterial amyloid proteins, such as curli, in promoting proteotoxicity and neurodegeneration by cross-seeding the aggregation of endogenous ND-related proteins, such as &#945;-synuclein. Targeting bacterial amyloid production may serve as a novel therapeutic strategy for treating NDs, and several compounds, such as epigallocatechin-3-gallate (EGCG), were shown to suppress neurodegeneration at least partly by inhibiting curli production. Because bacterial amyloid fibrils contribute to biofilm formation, inhibition of amyloid production often leads to the disruption of biofilms. Interestingly, from a list of 59 compounds that showed neuroprotective effects in C. elegans and mouse ND models, we found that about half of them are known to inhibit bacterial growth or biofilm formation, suggesting a strong correlation between the neuroprotective and antibiofilm activities. Whether these potential therapeutics indeed protect neurons from proteotoxicity by inhibiting the cross-seeding between bacterial and human amyloid proteins awaits further investigations. Finally, we propose to screen the long list of antibiofilm agents, both FDA-approved drugs and novel compounds, for their neuroprotective effects and develop new pharmaceuticals that target the gut microbiome for the treatment of NDs. To this end, the C. elegans ND models can serve as a platform for fast, high-throughput, and low-cost drug screens that target the microbe-host interaction in NDs.

Wang C et al. (2011) J Food Prot "Use of Caenorhabditis elegans for preselecting Lactobacillus isolates to control Salmonella Typhimurium."

Si W, Sabour PM, Wang J, Gong J, Wang C, Pacan JC, Niu Z, Yu H

[J Food Prot, 2011]

Host-specific probiotics have been used to control enteric pathogens, including foodborne pathogens, in food animal production. However, evaluation of the efficacy of these probiotics requires costly in vivo assays in the target animal. The nematode Caenorhabditis elegans has been used for prescreening of antimicrobial agents and for studies of host-pathogen interactions. In the present study, 17 Lactobacillus isolates from chicken and pig intestines were tested with C. elegans, and the ability of these isolates to prevent death from Salmonella infection was variable. Two Lactobacillus isolates (S64, which gave full protection, and CL11, which gave no protection) were further studied. Both isolates exhibited a similar colonization profile in the C. elegans intestine. Although different culture fractions of CL11 were not protective, both live and heat-killed S64 cells provided full or partial protection of C. elegans from death caused by Salmonella infection. In contrast, different culture fractions from both isolates had similar effects on the colonization of the nematode intestine by Salmonella Typhimurium DT104. Our preliminary results from a pig performance trial revealed a correlation between the degree of protection in the C. elegans survival assay and the performance of 35-day-old weaned piglets that were treated with the same Lactobacillus isolates, suggesting that C. elegans can be used as a laboratory animal model for preselecting probiotics for control of Salmonella infections.

Wang C et al. (2022) Nat Commun "A conserved megaprotein-based molecular bridge critical for lipid trafficking and cold resilience."

Lin W, Liu Y, Long Y, Deng H, Shen K, Ma DK, Oh F, Sima J, Wang B, Bassik M, Guo R, Pandey T, Mukherjee S, Zhang C, McDonald JG, Vale G, Wang C, Zhang J

[Nat Commun, 2022]

Cells adapt to cold by increasing levels of unsaturated phospholipids and membrane fluidity through conserved homeostatic mechanisms. Here we report an exceptionally large and evolutionarily conserved protein LPD-3 in C. elegans that mediates lipid trafficking to confer cold resilience. We identify lpd-3 mutants in a mutagenesis screen for genetic suppressors of the lipid desaturase FAT-7. LPD-3 bridges the endoplasmic reticulum (ER) and plasma membranes (PM), forming a structurally predicted hydrophobic tunnel for lipid trafficking. lpd-3 mutants exhibit abnormal phospholipid distribution, diminished FAT-7 abundance, organismic vulnerability to cold, and are rescued by Lecithin comprising unsaturated phospholipids. Deficient lpd-3 homologues in Zebrafish and mammalian cells cause defects similar to those observed in C. elegans. As mutations in BLTP1, the human orthologue of lpd-3, cause Alkuraya-Kucinskas syndrome, LPD-3 family proteins may serve as evolutionarily conserved highway bridges critical for ER-associated non-vesicular lipid trafficking and resilience to cold stress in eukaryotic cells.