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Li J, Bi H. Molecular mechanisms of atrazine toxicity on H19-7 hippocampal neurons revealed by integrated miRNA and mRNA "omics". ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 253:114681. [PMID: 36841081 DOI: 10.1016/j.ecoenv.2023.114681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Atrazine (ATR) is a widely applied herbicide in Asia and South America with slow natural degradation and documented deleterious effects on human and animal health, including hippocampal toxicity. However, relatively little is known about the molecular mechanisms responsible for ATR-induced hippocampal damage. Screening for differentially expressed mRNAs and microRNAs (miRNAs), and construction of potential miRNA-mRNA regulatory networks can reveal such mechanisms, so we analyzed the mRNA and miRNA expression profiles of rat hippocampus-derived H19-7 cells in response to ATR (500 μM) and conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment (KEGG) analyses. Integration of miRNA sequencing (miRNA-seq) and mRNA sequencing (mRNA-seq) results identified 114 differentially expressed miRNAs (DEMIs, 40 upregulated and 74 downregulated), and 510 differentially expressed mRNAs (DEMs, 177 upregulated and 333 downregulated) targeted by these DEMIs. The top 10 hub mRNAs (Fos, Prkcb, Ncf1, Vcam1, Atf3, Pak3, Pak1, Cacna1s, Junb, and Ccl2) and 19 related miRNAs (rno-miR-194-5p, rno-miR-24-3p, rno-miR-3074, rno-miR-1949, rno-miR-218a-1-3p, rno-miR-1843a-5p, rno-miR-1843b-5p, rno-miR-296-3p, rno-miR-320-3p, rno-miR-219a-1-3p, rno-miR-122-5p, rno-miR-1839-5p, rno-miR-1843a-3p, rno-miR-215, rno-miR-3583-3p, rno-miR-194-3p, rno-miR-128-1-5p, rno-miR-1956-5p, and rno-miR-466b-2-3p) were validated by quantitative real-time PCR. GO analysis indicated that these DEMs were enriched in genes associated with synaptic plasticity and antioxidant capacity, while KEGG analysis suggested that enriched DEMs were involved in calcium signaling, axon guidance, MAPK signaling, and glial carcinogenesis. The miRNA-mRNA regulatory network identified here may provide potential biomarkers and novel strategies for the treatment of hippocampal neurotoxicity induced by ATR.
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Affiliation(s)
- Jianan Li
- Department of Occupational and Environmental Health, College of Public Health, Xuzhou Medical University, 209 Tongshan Road, Yun Long District, Xuzhou 221000, China.
| | - Haoran Bi
- Department of Biostatistics, College of Public Health, Xuzhou Medical University, 209 Tongshan Road, Yun Long District, Xuzhou 221000, China.
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Regulation of TLR4 signaling through the TRAF6/sNASP axis by reversible phosphorylation mediated by CK2 and PP4. Proc Natl Acad Sci U S A 2021; 118:2107044118. [PMID: 34789577 DOI: 10.1073/pnas.2107044118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2021] [Indexed: 02/06/2023] Open
Abstract
Recognition of invading pathogens by Toll-like receptors (TLRs) activates innate immunity through signaling pathways that involved multiple protein kinases and phosphatases. We previously demonstrated that somatic nuclear autoantigenic sperm protein (sNASP) binds to TNF receptor-associated factor 6 (TRAF6) in the resting state. Upon TLR4 activation, a signaling complex consisting of TRAF6, sNASP, interleukin (IL)-1 receptor-associated kinase 4, and casein kinase 2 (CK2) is formed. CK2 then phosphorylates sNASP to release phospho-sNASP (p-sNASP) from TRAF6, initiating downstream signaling pathways. Here, we showed that protein phosphatase 4 (PP4) is the specific sNASP phosphatase that negatively regulates TLR4-induced TRAF6 activation and its downstream signaling pathway. Mechanistically, PP4 is directly recruited by phosphorylated sNASP to dephosphorylate p-sNASP to terminate TRAF6 activation. Ectopic expression of PP4 specifically inhibited sNASP-dependent proinflammatory cytokine production and downstream signaling following bacterial lipopolysaccharide (LPS) treatment, whereas silencing PP4 had the opposite effect. Primary macrophages and mice infected with recombinant adenovirus carrying a gene encoding PP4 (Ad-PP4) showed significant reduction in IL-6 and TNF-α production. Survival of Ad-PP4-infected mice was markedly increased due to a better ability to clear bacteria in a sepsis model. These results indicate that the serine/threonine phosphatase PP4 functions as a negative regulator of innate immunity by regulating the binding of sNASP to TRAF6.
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Lajarín-Cuesta R, Arribas RL, Nanclares C, García-Frutos EM, Gandía L, de los Ríos C. Design and synthesis of multipotent 3-aminomethylindoles and 7-azaindoles with enhanced protein phosphatase 2A-activating profile and neuroprotection. Eur J Med Chem 2018; 157:294-309. [DOI: 10.1016/j.ejmech.2018.07.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/09/2018] [Accepted: 07/11/2018] [Indexed: 02/02/2023]
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Striatal-enriched protein tyrosine phosphatase modulates nociception: evidence from genetic deletion and pharmacological inhibition. Pain 2016; 157:377-386. [PMID: 26270590 DOI: 10.1097/j.pain.0000000000000329] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The information from nociceptors is processed in the dorsal horn of the spinal cord by complex circuits involving excitatory and inhibitory interneurons. It is well documented that GluN2B and ERK1/2 phosphorylation contributes to central sensitization. Striatal-enriched protein tyrosine phosphatase (STEP) dephosphorylates GluN2B and ERK1/2, promoting internalization of GluN2B and inactivation of ERK1/2. The activity of STEP was modulated by genetic (STEP knockout mice) and pharmacological (recently synthesized STEP inhibitor, TC-2153) approaches. STEP(61) protein levels in the lumbar spinal cord were determined in male and female mice of different ages. Inflammatory pain was induced by complete Freund's adjuvant injection. Behavioral tests, immunoblotting, and electrophysiology were used to analyze the effect of STEP on nociception. Our results show that both genetic deletion and pharmacological inhibition of STEP induced thermal hyperalgesia and mechanical allodynia, which were accompanied by increased pGluN2B(Tyr1472) and pERK1/2(Thr202/Tyr204)levels in the lumbar spinal cord. Striatal-enriched protein tyrosine phosphatase heterozygous and knockout mice presented a similar phenotype. Furthermore, electrophysiological experiments showed that TC-2153 increased C fiber-evoked spinal field potentials. Interestingly, we found that STEP(61) protein levels in the lumbar spinal cord inversely correlated with thermal hyperalgesia associated with age and female gender in mice. Consistently, STEP knockout mice failed to show age-related thermal hyperalgesia, although gender-related differences were preserved. Moreover, in a model of inflammatory pain, hyperalgesia was associated with increased phosphorylation-mediated STEP(61) inactivation and increased pGluN2B(Tyr1472) and pERK1/2(Thr202/Tyr204)levels in the lumbar spinal cord. Collectively, the present results underscore an important role of spinal STEP activity in the modulation of nociception.
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Lin TB, Hsieh MC, Lai CY, Cheng JK, Wang HH, Chau YP, Chen GD, Peng HY. Melatonin relieves neuropathic allodynia through spinal MT2-enhanced PP2Ac and downstream HDAC4 shuttling-dependent epigenetic modification of hmgb1 transcription. J Pineal Res 2016; 60:263-76. [PMID: 26732138 DOI: 10.1111/jpi.12307] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 01/04/2016] [Indexed: 01/11/2023]
Abstract
Melatonin (MLT; N-acetyl-5-methoxytryptamine) exhibits analgesic properties in chronic pain conditions. While researches linking MLT to epigenetic mechanisms have grown exponentially over recent years, very few studies have investigated the contribution of MLT-associated epigenetic modification to pain states. Here, we report that together with behavioral allodynia, spinal nerve ligation (SNL) induced a decrease in the expression of catalytic subunit of phosphatase 2A (PP2Ac) and enhanced histone deacetylase 4 (HDAC4) phosphorylation and cytoplasmic accumulation, which epigenetically alleviated HDAC4-suppressed hmgb1 gene transcription, resulting in increased high-mobility group protein B1 (HMGB1) expression selectively in the ipsilateral dorsal horn of rats. Focal knock-down of spinal PP2Ac expression also resulted in behavioral allodynia in association with similar protein expression as observed with SNL. Notably, intrathecal administration with MLT increased PP2Ac expression, HDAC4 dephosphorylation and nuclear accumulation, restored HDAC4-mediated hmgb1 suppression and relieved SNL-sensitized behavioral pain; these effects were all inhibited by spinal injection of 4P-PDOT (a MT2 receptor antagonist, 30 minutes before MLT) and okadaic acid (OA, a PP2A inhibitor, 3 hr after MLT). Our findings demonstrate a novel mechanism by which MLT ameliorates neuropathic allodynia via epigenetic modification. This MLT-exhibited anti-allodynia is mediated by MT2-enhanced PP2Ac expression that couples PP2Ac with HDAC4 to induce HDAC4 dephosphorylation and nuclear import, herein increases HDAC4 binding to the promoter of hmgb1 gene and upregulates HMGB1 expression in dorsal horn neurons.
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Affiliation(s)
- Tzer-Bin Lin
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Basic Medical Science, College of Medicine, China Medical University, Taichung, Taiwan
- Department of Biotechnology, Asia University, Taichung, Taiwan
| | - Ming-Chun Hsieh
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yuan Lai
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan
| | - Jen-Kun Cheng
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
- Department of Anesthesiology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Hsueh-Hsiao Wang
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Yat-Pang Chau
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Gin-Den Chen
- Department of Obstetrics and Gynecology, Chung-Shan Medical University Hospital, Chung-Shan Medical University, Taichung, Taiwan
| | - Hsien-Yu Peng
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
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Kück U, Beier AM, Teichert I. The composition and function of the striatin-interacting phosphatases and kinases (STRIPAK) complex in fungi. Fungal Genet Biol 2015; 90:31-38. [PMID: 26439752 DOI: 10.1016/j.fgb.2015.10.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 09/30/2015] [Accepted: 10/02/2015] [Indexed: 02/06/2023]
Abstract
The striatin-interacting phosphatases and kinases (STRIPAK) complex is a highly conserved eukaryotic protein complex that was recently described for diverse animal and fungal species. Here, we summarize our current knowledge about the composition and function of the STRIPAK complex from the ascomycete Sordaria macrospora, which we discovered by investigating sexually sterile mutants (pro), having a defect in fruiting body development. Mass spectrometry and yeast two-hybrid analysis defined core subunits of the STRIPAK complex, which have structural homologs in animal and other fungal organisms. These subunits (and their mammalian homologs) are PRO11 (striatin), PRO22 (STRIP1/2), SmMOB3 (Mob3), PRO45 (SLMAP), and PP2AA, the structural, and PP2Ac, the catalytic subunits of protein phosphatase 2A (PP2A). Beside fruiting body formation, the STRIPAK complex controls vegetative growth and hyphal fusion in S. macrospora. Although the contribution of single subunits to diverse cellular and developmental processes is not yet fully understood, functional analysis has already shown that mammalian homologs are able to substitute the function of distinct fungal STRIPAK subunits. This underscores the view that fungal model organisms serve as useful tools to get a molecular insight into cellular and developmental processes of eukaryotes in general. Future work will unravel the precise localization of single subunits within the cell and decipher their STRIPAK-related and STRIPAK-independent functions. Finally, evidence is accumulating that there is a crosstalk between STRIPAK and various signaling pathways, suggesting that eukaryotic development is dependent on STRIPAK signaling.
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Affiliation(s)
- Ulrich Kück
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, Universitätsstr. 150, 44780 Bochum, Germany.
| | - Anna M Beier
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, Universitätsstr. 150, 44780 Bochum, Germany
| | - Ines Teichert
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, Universitätsstr. 150, 44780 Bochum, Germany
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Saul N, Chakrabarti S, Stürzenbaum SR, Menzel R, Steinberg CEW. Neurotoxic action of microcystin-LR is reflected in the transcriptional stress response of Caenorhabditis elegans. Chem Biol Interact 2014; 223:51-7. [PMID: 25257166 DOI: 10.1016/j.cbi.2014.09.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 08/27/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
Abstract
Cyanobacterial blooms in aquatic environments are frequently characterized by elevated levels of microcystins, a potent hepatotoxin. Here we exposed the nematode Caenorhabditis elegans with environmentally realistic concentrations of MC-LR to explore its non-hepatic toxicity. Lifespan, reproduction and growth assays confirmed the toxic potential of 100μg/L MC-LR even in this liver-lacking invertebrate. Whole-genome microarray analysis revealed that a neuromodulating action was the dominant response in nematodes challenged with 100μg/L MC-LR. Indeed, most of the 201 differentially expressed genes were associated with neurobehavior, neurogenesis, and signaling associated pathways. In addition, a whole-genome miRNA-microarray highlighted that, in particular, members of the let-7 family were differentially regulated. These miRNAs are involved in the developmental timing of cell fates, including neurons, and are probably also part of the stress response system. To conclude, neurological modulation is the main transcriptional stress response in C. elegans exposed to MC-LR.
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Affiliation(s)
- Nadine Saul
- Department of Biology, Freshwater and Stress Ecology, Humboldt-Universität zu Berlin, Späthstr. 80/81, 12437 Berlin, Germany.
| | - Shumon Chakrabarti
- Department of Biology, Freshwater and Stress Ecology, Humboldt-Universität zu Berlin, Späthstr. 80/81, 12437 Berlin, Germany
| | - Stephen R Stürzenbaum
- School of Biomedical Sciences, Analytical and Environmental Sciences Division, King's College London, 150 Stamford Street, London SE1 9NH, UK
| | - Ralph Menzel
- Department of Biology, Freshwater and Stress Ecology, Humboldt-Universität zu Berlin, Späthstr. 80/81, 12437 Berlin, Germany
| | - Christian E W Steinberg
- Department of Biology, Freshwater and Stress Ecology, Humboldt-Universität zu Berlin, Späthstr. 80/81, 12437 Berlin, Germany
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Microcystins alter chemotactic behavior in Caenorhabditis elegans by selectively targeting the AWA sensory neuron. Toxins (Basel) 2014; 6:1813-36. [PMID: 24918360 PMCID: PMC4073131 DOI: 10.3390/toxins6061813] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 05/17/2014] [Accepted: 05/28/2014] [Indexed: 11/16/2022] Open
Abstract
Harmful algal blooms expose humans and animals to microcystins (MCs) through contaminated drinking water. While hepatotoxicity following acute exposure to MCs is well documented, neurotoxicity after sub-lethal exposure is poorly understood. We developed a novel statistical approach using a generalized linear model and the quasibinomial family to analyze neurotoxic effects in adult Caenorhabditis elegans exposed to MC-LR or MC-LF for 24 h. Selective effects of toxin exposure on AWA versus AWC sensory neuron function were determined using a chemotaxis assay. With a non-monotonic response MCs altered AWA but not AWC function, and MC-LF was more potent than MC-LR. To probe a potential role for protein phosphatases (PPs) in MC neurotoxicity, we evaluated the chemotactic response in worms exposed to the PP1 inhibitor tautomycin or the PP2A inhibitor okadaic acid for 24 h. Okadaic acid impaired both AWA and AWC function, while tautomycin had no effect on function of either neuronal cell type at the concentrations tested. These findings suggest that MCs alter the AWA neuron at concentrations that do not cause AWC toxicity via mechanisms other than PP inhibition.
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