Wang P et al. (2006) Dev Biol "Identification of novel target genes of CeTwist and CeE/DA."

Zhao J, Corsi AK, Wang P

[Dev Biol, 2006]

Twist, a basic helix-loop-helix (bHLH) transcription factor, plays an important role in mesoderm development in many organisms, including C. elegans where CeTwist is required to direct cell fate specifications of a subset of mesodermal cells. Although several target genes of CeTwist have been identified, how this protein accomplishes its function is unclear. In addition, several human genes whose mutations cause different syndromes of craniosynostosis (premature fusion of cranial sutures) have homologues in the CeTwist pathway. Identification of novel target genes of CeTwist will shed more light on the functions of CeTwist in mesoderm development, and the corresponding human homologues will be good candidates for related syndromes with unidentified mutated genes. In our study, both CeTwist and its heterodimeric partner, CeE/DA, were overexpressed from the inducible heat-shock promoter, and potential target genes were detected with Affymetrix(R) oligonucleotide microarrays. Using transcriptional GFP reporters, we found 11 genes were expressed in cells coincident with known CeTwist target gene products. Based on subsequent validation experiments, 9 genes were defined as novel CeTwist and CeE/DA targets. Human homologues of two of these genes might be involved in craniofacial diseases, which further validates C. elegans as a good model organism for providing insights into these disorders.

Wang P et al. (2013) Autophagy "Nutrient-driven O-GlcNAc cycling influences autophagic flux and neurodegenerative proteotoxicity."

Hanover JA, Wang P

[Autophagy, 2013]

O-GlcNAcylation is an abundant post-translational modification implicated in human neurodegenerative diseases. We showed that loss-of-function of OGT (O-linked GlcNAc transferase) alleviated, while loss of OGA (O-GlcNAc selective -N-acetyl-D-glucosaminidase) enhanced, the proteotoxicity of C. elegans neurodegenerative disease models including tauopathy, -amyloid peptide and polyglutamine expansion. The O-GlcNAc cycling mutants act, in part, by altering insulin signaling, proteasome activity and autophagy. In mutants lacking either of these enzymes of O-GlcNAc cycling, there is a striking accumulation of GFP::LGG-1 (C. elegans homolog of Atg8 and LC3) and increased phosphatidylethanolamine (PE)-modified GFP::LGG-1 upon starvation. We speculate that O-GlcNAc cycling is a key nutrient-responsive regulator of autophagic flux acting at multiple levels including direct modification of BECN1 and BCL2.

Wang P et al. (2023) STAR Protoc "Protocol for CRISPR-Cas9-mediated genome editing to study spermatogenesis in Caenorhabditis elegans."

Chen L, Wang P, Cao Z, Wang Q, Zhao Y, Miao L, Wang N, Ma X

[STAR Protoc, 2023]

Gene silencing by P-element-induced wimpy testis-interacting RNAs is a mechanism to maintain genome integrity in germ cells. Here, we present a protocol for knockin or knockout editing of male germline genome mediated by CRISPR-Cas9 technology in Caenorhabditis elegans. We describe steps for constructing edited plasmids, microinjecting worms with these plasmids, and screening edited worms. We then detail procedures for dissecting released sperm and their observation with fluorescence microscopy. Engineered worms provide a model for studying hermaphrodite/male fertility or protein localization in vivo. For complete details on the use and execution of this protocol, please refer to Wang et al. (2021).¹.

Wang P et al. (2016) PLoS Genet "RAB-10 Promotes EHBP-1 Bridging of Filamentous Actin and Tubular Recycling Endosomes."

Shi A, Wang Y, Yang Z, Gleason A, Grant BD, Zhang J, Wang P, Liu O, Wang H, Liu H

[PLoS Genet, 2016]

EHBP-1 (Ehbp1) is a conserved regulator of endocytic recycling, acting as an effector of small GTPases including RAB-10 (Rab10). Here we present evidence that EHBP-1 associates with tubular endosomal phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2] enriched membranes through an N-terminal C2-like (NT-C2) domain, and define residues within the NT-C2 domain that mediate membrane interaction. Furthermore, our results indicate that the EHBP-1 central calponin homology (CH) domain binds to actin microfilaments in a reaction that is stimulated by RAB-10(GTP). Loss of any aspect of this RAB-10/EHBP-1 system in the C. elegans intestinal epithelium leads to retention of basolateral recycling cargo in endosomes that have lost their normal tubular endosomal network (TEN) organization. We propose a mechanism whereby RAB-10 promotes the ability of endosome-bound EHBP-1 to also bind to the actin cytoskeleton, thereby promoting endosomal tubulation.

Wang P et al. (2022) Food Chem X "Acylating blueberry anthocyanins with fatty acids: Improvement of their lipid solubility and antioxidant activities."

Zhuang Y, Fei P, Wang P, Liu J

[Food Chem X, 2022]

Aimed at exploring the impact of fatty acid side chains on the anthocyanins, n-valeric acid, n-decanoic acid and myristic acid were used to grafting onto the blueberry anthocyanins, and the acylating degree value of the of n-valeric acid acylated anthocyanins (Va-An), n-decanoic acid acylated anthocyanins (De-An) and myristic acid acylated anthocyanins (My-An) reached 6.43 %, 7.56% and 8.38 %, respectively. After acylation modification, the octanol-water partition coefficient of the anthocyanins increased from -0.20 (native anthocyanins, Na-An) to 0.65 (Va-An), 0.66 (De-An) and 0.72 (My-An), respectively, indicating the increasement of the lipid solubility. Besides, although the DPPH clearance of acylated anthocyanins was lower than that of native anthocyanins, the inhibition ratio of β-carotene bleaching and malonaldehyde reduction effect of the acylated blueberry anthocyanins in Caenorhabditis elegans were both stronger than that of native anthocyanins, which might be caused by the improvement of lipid solubility of the anthocyanins.

Wang P et al. (2024) Development "Mitochondrial defects triggered by amg-1 mutation elicit UPRmt and phagocytic clearance during spermatogenesis in C. elegans."

Wang N, Chen L, Wang P, Zhao Y, Miao L

[Development, 2024]

Mitochondria are the powerhouses of many biological processes. During spermatogenesis, post-transcriptional regulation of mitochondrial gene expression is mediated by nuclear-encoded mitochondrial RNA-binding proteins (mtRBPs). We identified AMG-1 as an mtRBP required for reproductive success in C. elegans. amg-1 mutation led to defects in mitochondrial structure and sperm budding, resulting in mitochondria being discarded into residual bodies (RBs), which ultimately delayed spermatogenesis in the proximal gonad. In addition, mitochondrial defects triggered the gonadal mitochondrial unfolded protein response and phagocytic clearance to ensure spermatogenesis but ultimately failed to rescue hermaphroditic fertility. These findings reveal a previously undiscovered role for AMG-1 in regulating C. elegans spermatogenesis, in which mitochondrial-damaged sperm prevented the transmission of defective mitochondria to mature sperm by budding and phagocytic clearance, which may also exist in the reproductive systems of higher organisms.

Wang P et al. (2014) Angew Chem Int Ed Engl "Imaging Lipid Metabolism in Live Caenorhabditis elegans Using Fingerprint Vibrations."

Cheng JX, Wang P, Tissenbaum HA, Zhang D, Liu B, Belew MY

[Angew Chem Int Ed Engl, 2014]

Quantitation of lipid storage, unsaturation, and oxidation in live C. elegans has been a long-standing obstacle. The combination of hyperspectral stimulated Raman scattering imaging and multivariate analysis in the fingerprint vibration region represents a platform that allows the quantitative mapping of fat distribution, degree of fat unsaturation, lipid oxidation, and cholesterol storage in vivo in the whole worm. Our results reveal for the first time that lysosome-related organelles in intestinal cells are sites for storage of cholesterol in C. elegans.

Wang P et al. (2010) Neuronal Development, Synaptic Function and Behavior, Madison, WI "Loss Of O-GlcNAc Is Neuroprotective In Caenorhabditis Elegans Models Of Human Neurodegenerative Diseases"

Hanover J A, Lazarus B D, Krause M K, Forsythe M E, Wang P, Love D C

[Neuronal Development, Synaptic Function and Behavior, Madison, WI, 2010]

The O-linked N-acetylglucosamine (O-GlcNAc) modification of serine or threonine hydroxyl group is a dynamic, post-translational process mediated by two evolutionally conserved enzymes: O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), which add or remove O-GlcNAc, respectively. This process modifies and regulates more than 600 proteins. Deregulation of this process is involved in various human diseases including diabetes mellitus, cancer, and neurodegenerative diseases. One common signature of neurodegenerative diseases is the formation of protein aggregates, which lead to neuronal degeneration and death. Ectopically expressing aggregate-prone human proteins in C. elegans neurons or muscles provides a whole and simple model organism for studying these complicated diseases. The transparency of the worm allows real-time observation of protein aggregates in live animals. And the short life span of C. elegans makes it more feasible to investigate the effects of aging on neurodegeration. Null mutants of OGT or OGA in C. elegans are viable and fertile, compared to lethal in mammals, making it a good model system to investigate the effects of deregulation of O-GlcNAc modification in C. elegans neurodegenerative models. Proteotoxicity in different C. elegans models was compared in wild type, ogt-1 mutant, or oga-1 mutant background. We found that the ogt-1 mutation alleviated and the oga-1 mutation enhanced the toxicity of aggregate-prone proteins such as FTDP-17 Tau, beta amyloid, and polyglutamine (polyQ). Furthermore, the enhanced proteotoxicity of polyQ found in oga-1 mutants was reversed by ogt-1 mutation, indicating that absence of O-GlcNAc modification leads to reduction of the aggregate-associated proteotoxicity. Our data also showed elevated proteasome activity in ogt-1 mutants, suggesting a faster turnover of the protein aggregates accounts for the phenotypic alleviation observed in this background. The regulation of O-GlcNAc modification of another protein quality control pathway, autophagy, is currently under investigation. These results indicate that OGT and OGA counteract each other in regulating proteotoxicity in multiple neurodegenerative disease models, and regulation of protein quality control pathways by O-GlcNAc modification could be the underlying mechanism.

Wang P et al. (2012) Proc Natl Acad Sci U S A "O-GlcNAc cycling mutants modulate proteotoxicity in Caenorhabditis elegans models of human neurodegenerative diseases."

Love DC, Wang P, Hanover JA, Krause MW, Lazarus BD, Forsythe ME

[Proc Natl Acad Sci U S A, 2012]

O-GlcNAcylation is an abundant posttranslational modification in the brain implicated in human neurodegenerative diseases. We have exploited viable null alleles of the enzymes of O-GlcNAc cycling to examine the role of O-GlcNAcylation in well-characterized Caenorhabditis elegans models of neurodegenerative proteotoxicity. O-GlcNAc cycling dramatically modulated the severity of the phenotype in transgenic models of tauopathy, amyloid -peptide, and polyglutamine expansion. Intriguingly, loss of function of O-GlcNAc transferase alleviated, whereas loss of O-GlcNAcase enhanced, the phenotype of multiple neurodegenerative disease models. The O-GlcNAc cycling mutants act in part by altering DAF-16-dependent transcription and modulating the protein degradation machinery. These findings suggest that O-GlcNAc levels may directly influence neurodegenerative disease progression, thus making the enzymes of O-GlcNAc cycling attractive targets for neurodegenerative disease therapies.

Po-Shen Wang P et al. (2012) Genome Biol Evol "Family size and turnover rates among several classes of small non-protein-coding RNA genes in Caenorhabditis nematodes."

Ruvinsky I, Po-Shen Wang P

[Genome Biol Evol, 2012]

It is important to understand the forces that shape the size and evolutionary histories of gene families. Here, we investigated the evolution of non-protein-coding RNA genes in the genomes of Caenorhabditis nematodes. We specifically focused on nested arrangements, that is, cases in which an RNA gene is entirely contained in an intron of another gene. Comparing these arrangements between species simplifies the inference of orthology and, therefore, of evolutionary fates of nested genes. Two distinct patterns are evident in the data. Genes encoding small nuclear RNAs (snRNAs) and transfer RNAs form large families, which have persisted since before the common ancestor of Metazoa. Yet, individual genes die relatively rapidly, with few orthologs having survived since the divergence of Caenorhabditis elegans and Caenorhabditis briggsae. In contrast, genes encoding small nucleolar RNAs (snoRNAs) are either single-copy or form small families. Individual snoRNAs turn over at a relatively slow rate-most C. elegans genes have clearly identifiable orthologs in C. briggsae. We also found that in Drosophila, genes from larger snRNA families die at a faster rate than their counterparts from single-gene families. These results suggest that a relationship between family size and the rate of gene turnover may be a general feature of genome evolution.