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Packer J, Gubieda AG, Brooks A, Deutz LN, Squires I, Ellison S, Schneider C, Naganathan SR, Wollman AJM, Dickinson DJ, Rodriguez J. Atypical Protein Kinase C Promotes its own Asymmetric Localisation by Phosphorylating Cdc42 in Polarising Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.10.27.563985. [PMID: 38009101 PMCID: PMC10675845 DOI: 10.1101/2023.10.27.563985] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2023]
Abstract
Atypical protein kinase C (aPKC) is a major regulator of cell polarity. Acting in conjunction with Par6, Par3 and the small GTPase Cdc42, aPKC becomes asymmetrically localised and drives the polarisation of cells. aPKC activity is crucial for its own asymmetric localisation, suggesting a hitherto unknown feedback mechanism contributing to polarisation. Here we show in the C. elegans zygote that the feedback relies on aPKC phosphorylation of Cdc42 at serine 71. The turnover of CDC-42 phosphorylation ensures optimal aPKC asymmetry and activity throughout polarisation by tuning Par6/aPKC association with Par3 and Cdc42. Moreover, turnover of Cdc42 phosphorylation regulates actomyosin cortex dynamics that are known to drive aPKC asymmetry. Given the widespread role of aPKC and Cdc42 in cell polarity, this form of self-regulation of aPKC may be vital for the robust control of polarisation in many cell types.
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Knudsen-Palmer DR, Raman P, Ettefa F, De Ravin L, Jose AM. Target-specific requirements for RNA interference can arise through restricted RNA amplification despite the lack of specialized pathways. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.07.527351. [PMID: 36798330 PMCID: PMC9934570 DOI: 10.1101/2023.02.07.527351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Since double-stranded RNA (dsRNA) is effective for silencing a wide variety of genes, all genes are typically considered equivalent targets for such RNA interference (RNAi). Yet, loss of some regulators of RNAi in the nematode C. elegans can selectively impair the silencing of some genes. Here we show that such selective requirements can be explained by an intersecting network of regulators acting on genes with differences in their RNA metabolism. In this network, the Maelstrom domain-containing protein RDE-10, the intrinsically disordered protein MUT-16, and the Argonaute protein NRDE-3 work together so that any two are required for silencing one somatic gene, but each is singly required for silencing another somatic gene, where only the requirement for NRDE-3 can be overcome by enhanced dsRNA processing. Quantitative models and their exploratory simulations led us to find that (1) changing cis -regulatory elements of the target gene can reduce the dependence on NRDE-3, (2) animals can recover from silencing in non-dividing cells and (3) cleavage and tailing of mRNAs with UG dinucleotides, which makes them templates for amplifying small RNAs, is enriched within 'pUG zones' matching the dsRNA. Similar crosstalk between pathways and restricted amplification could result in apparently selective silencing by endogenous RNAs.
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Leuthner TC, Zhang S, Kohrn BF, Stapleton HM, Baugh LR. Structure-specific variation in per- and polyfluoroalkyl substances toxicity among genetically diverse Caenorhabditis elegans strains. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596269. [PMID: 38854041 PMCID: PMC11160736 DOI: 10.1101/2024.05.29.596269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Background There are >14,500 structurally diverse per- and polyfluoroalkyl substances (PFAS). Despite knowledge that these "forever chemicals" are in 99% of humans, mechanisms of toxicity and adverse health effects are incompletely known. Furthermore, the contribution of genetic variation to PFAS susceptibility and health consequences is unknown. Objectives We determined the toxicity of a structurally distinct set of PFAS in twelve genetically diverse strains of the genetic model system Caenorhabditis elegans. Methods Dose-response curves for four perfluoroalkyl carboxylic acids (PFNA, PFOA, PFPeA, and PFBA), two perfluoroalkyl sulfonic acids (PFOS and PFBS), two perfluoroalkyl sulfonamides (PFOSA and PFBSA), two fluoroether carboxylic acids (GenX and PFMOAA), one fluoroether sulfonic acid (PFEESA), and two fluorotelomers (6:2 FCA and 6:2 FTS) were determined in the C. elegans laboratory reference strain, N2, and eleven genetically diverse wild strains. Body length was quantified by image analysis at each dose after 48 hr of developmental exposure of L1 arrest-synchronized larvae to estimate effective concentration values (EC50). Results There was a significant range in toxicity among PFAS: PFOSA > PFBSA ≈ PFOS ≈ PFNA > PFOA > GenX ≈ PFEESA > PFBS ≈ PFPeA ≈ PFBA. Long-chain PFAS had greater toxicity than short-chain, and fluorosulfonamides were more toxic than carboxylic and sulfonic acids. Genetic variation explained variation in susceptibility to PFBSA, PFOS, PFBA, PFOA, GenX, PFEESA, PFPeA, and PFBA. There was significant variation in toxicity among C. elegans strains due to chain length, functional group, and between legacy and emerging PFAS. Conclusion C. elegans respond to legacy and emerging PFAS of diverse structures, and this depends on specific structures and genetic variation. Harnessing the natural genetic diversity of C. elegans and the structural complexity of PFAS is a powerful New Approach Methodology (NAM) to investigate structure-activity relationships and mechanisms of toxicity which may inform regulation of other PFAS to improve human and environmental health.
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Affiliation(s)
- Tess C. Leuthner
- Department of Biology, Duke University, Durham, North Carolina, USA
| | - Sharon Zhang
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - Brendan F Kohrn
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Heather M. Stapleton
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - L. Ryan Baugh
- Department of Biology, Duke University, Durham, North Carolina, USA
- Center for Genomic and Computational Biology, Duke University, North Carolina, USA
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Catela C, Assimacopoulos S, Chen Y, Tsioras K, Feng W, Kratsios P. The Iroquois ( Iro/Irx) homeobox genes are conserved Hox targets involved in motor neuron development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.30.596714. [PMID: 38853975 PMCID: PMC11160718 DOI: 10.1101/2024.05.30.596714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
The Iroquois (Iro/Irx) homeobox genes encode transcription factors with fundamental roles in animal development. Despite their link to various congenital conditions in humans, our understanding of Iro/Irx gene expression, function, and regulation remains incomplete. Here, we conducted a systematic expression analysis of all six mouse Irx genes in the embryonic spinal cord. We found five Irx genes (Irx1, Irx2, Irx3, Irx5, and Irx6) to be confined mostly to ventral spinal domains, offering new molecular markers for specific groups of post-mitotic motor neurons (MNs). Further, we engineered Irx2, Irx5, and Irx6 mouse mutants and uncovered essential but distinct roles for Irx2 and Irx6 in MN development. Last, we found that the highly conserved regulators of MN development across species, the HOX proteins, directly control Irx gene expression both in mouse and C. elegans MNs, critically expanding the repertoire of HOX target genes in the developing nervous system. Altogether, our study provides important insights into Iro/Irx expression and function in the developing spinal cord, and uncovers an ancient gene regulatory relationship between HOX and Iro/Irx genes.
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Affiliation(s)
- Catarina Catela
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
| | - Stavroula Assimacopoulos
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
| | - Yihan Chen
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
| | - Konstantinos Tsioras
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
| | - Weidong Feng
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
| | - Paschalis Kratsios
- Department of Neurobiology, University of Chicago, Chicago, IL, USA
- Neuroscience Institute, University of Chicago, Chicago, IL, USA
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Gajjar G, Huggins HP, Kim ES, Huang W, Bonnet FX, Updike DL, Keiper BD. Two germ granule eIF4E isoforms reside in different mRNPs to hand off C elegans mRNAs from translational repression to activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.24.595216. [PMID: 38826235 PMCID: PMC11142241 DOI: 10.1101/2024.05.24.595216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
We studied the function of translation factor eIF4E isoforms in regulating mRNAs in germ cell granules/condensates. Translational control of mRNAs plays an essential role in germ cell gene regulation. Messenger ribonucleoprotein (mRNP) complexes assemble on mRNAs as they move from the nucleus into perinuclear germ granules to exert both positive and negative post-transcriptional regulation in the cytoplasm. In C. elegans , germ granules are surprisingly dynamic mRNP condensates that remodel during development. Two eIF4E isoforms (called IFE-1 and IFE-3), eIF4E-Interacting Proteins (4EIPs), RBPs, DEAD-box helicases, polyadenylated mRNAs, Argonautes and miRNAs all occupy positions in germ granules. Affinity purification of IFE-1 and IFE-3 allowed mass spectrometry and mRNA-Seq to identify the proteins and mRNAs that populate stable eIF4E mRNPs. We find translationally controlled mRNAs (e.g. pos-1, mex-3, spn-4, etc.) enriched in IFE-3 mRNPs, but excluded from IFE-1 mRNPs. These mRNAs also require IFE-1 for efficient translation. The findings support a model in which oocytes and embryos utilize the two eIF4Es for opposite purposes on critically regulated germline mRNAs. Careful colocalization of the eIF4Es with other germ granule components suggests an architecture in which GLH-1, PGL-1 and the IFEs are stratified to facilitate sequential interactions for mRNAs. Biochemical characterization demonstrates opposing yet cooperative roles for IFE-3 and IFE-1 to hand-off of translationally controlled mRNAs from the repressed to the activated state, respectively. The model involves eIF4E mRNPs shuttling mRNAs through nuclear pore-associated granules/condensates to cytoplasmic ribosomes.
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Mauro MS, Martin SL, Dumont J, Shirasu-Hiza M, Canman JC. Patterning, regulation, and role of FoxO/DAF-16 in the early embryo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.13.594029. [PMID: 38798632 PMCID: PMC11118310 DOI: 10.1101/2024.05.13.594029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Insulin resistance and diabetes are associated with many health issues including higher rates of birth defects and miscarriage during pregnancy. Because insulin resistance and diabetes are both associated with obesity, which also affects fertility, the role of insulin signaling itself in embryo development is not well understood. A key downstream target of the insulin/insulin-like growth factor signaling (IIS) pathway is the forkhead family transcription factor FoxO (DAF-16 in C. elegans ). Here, we used quantitative live imaging to measure the patterning of endogenously tagged FoxO/DAF-16 in the early worm embryo. In 2-4-cell stage embryos, FoxO/DAF-16 initially localized uniformly to all cell nuclei, then became dramatically enriched in germ precursor cell nuclei beginning at the 8-cell stage. This nuclear enrichment in early germ precursor cells required germ fate specification, PI3K (AGE-1)- and PTEN (DAF-18)-mediated phospholipid regulation, and the deubiquitylase USP7 (MATH-33), yet was unexpectedly insulin receptor (DAF-2)- and AKT-independent. Functional analysis revealed that FoxO/DAF-16 acts as a cell cycle pacer for early cleavage divisions-without FoxO/DAF-16 cell cycles were shorter than in controls, especially in germ lineage cells. These results reveal the germ lineage specific patterning, upstream regulation, and cell cycle role for FoxO/DAF-16 during early C. elegans embryogenesis.
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Ragle JM, Turzo A, Levenson MT, Jonnalagadda K, Jackson A, Vo AA, Pham VT, Ward JD. MLT-11 is a transient apical extracellular matrix component required for cuticle patterning and function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.12.593762. [PMID: 38766248 PMCID: PMC11100798 DOI: 10.1101/2024.05.12.593762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Apical extracellular matrices (aECMs) are associated with all epithelia and form a protective layer against biotic and abiotic threats in the environment. Despite their importance, we lack a deep understanding of their structure and dynamics in development and disease. C. elegans molting offers a powerful entry point to understanding developmentally programmed aECM remodeling. A transient matrix is formed in embryos and at the end of each larval stage, presumably to pattern the new cuticle. Focusing on targets of NHR-23, a key transcription factor which drives molting, we identified the Kunitz family protease inhibitor gene mlt-11 as an NHR-23 target. We identified NHR-23-binding sites that are necessary and sufficient for epithelial expression. mlt-11 is necessary to pattern every layer of the adult cuticle, suggesting a broad patterning role prior to the formation of the mature cuticle. MLT-11::mNeonGreen::3xFLAG transiently localized to the aECM in the cuticle and embryo. It was also detected in lining openings to the exterior (vulva, rectum, mouth). Reduction of mlt-11 function disrupted the barrier function of the cuticle. Tissue-specific RNAi suggested mlt-11 activity is primarily necessary in seam cells and we observed alae and seam cell fusion defects upon mlt-11 inactivation. Predicted mlt-11 null mutations caused fully penetrant embryonic lethality and elongation defects suggesting mlt-11 also plays an important role in patterning the embryonic sheath. Finally, we found that mlt-11 inactivation suppressed the blistered cuticle phenotype of mutants of bli-4 mutants, a subtilisin protease gene but did not affect BLI-4::sfGFP expression. These data could suggest that MLT-11 may be necessary to assure proper levels of BLI-4 activity.
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Affiliation(s)
- James Matthew Ragle
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Ariela Turzo
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Max T. Levenson
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Keya Jonnalagadda
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Anton Jackson
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - An A. Vo
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Vivian T. Pham
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Jordan D. Ward
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
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Spangler RK, Ashley GE, Braun K, Wruck D, Ramos-Coronado A, Ragle JM, Iesmantavicius V, Hess D, Partch CL, Großhans H, Ward JD. A conserved chronobiological complex times C. elegans development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.09.593322. [PMID: 38766223 PMCID: PMC11100808 DOI: 10.1101/2024.05.09.593322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
The mammalian PAS-domain protein PERIOD (PER) and its C. elegans orthologue LIN-42 have been proposed to constitute an evolutionary link between two distinct, circadian and developmental, timing systems. However, while the function of PER in animal circadian rhythms is well understood molecularly and mechanistically, this is not true for the function of LIN-42 in timing rhythmic development. Here, using targeted deletions, we find that the LIN-42 PAS domains are dispensable for the protein's function in timing molts. Instead, we observe arrhythmic molts upon deletion of a distinct sequence element, conserved with PER. We show that this element mediates stable binding to KIN-20, the C. elegans CK1δ/ε orthologue. We demonstrate that CK1δ phosphorylates LIN-42 and define two conserved helical motifs, CK1δ-binding domain A (CK1BD-A) and CK1BD-B, that have distinct roles in controlling CK1δ-binding and kinase activity in vitro. KIN-20 and the LIN-42 CK1BD are required for proper molting timing in vivo. These interactions mirror the central role of a stable circadian PER-CK1 complex in setting a robust ~24-hour period. Hence, our results establish LIN-42/PER - KIN-20/CK1δ/ε as a functionally conserved signaling module of two distinct chronobiological systems.
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Affiliation(s)
- Rebecca K Spangler
- Department of Chemistry and Biochemistry, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Guinevere E Ashley
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Kathrin Braun
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Daniel Wruck
- Department of Chemistry and Biochemistry, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Andrea Ramos-Coronado
- Department of Chemistry and Biochemistry, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - James Matthew Ragle
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | | | - Daniel Hess
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Carrie L Partch
- Department of Chemistry and Biochemistry, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
| | - Helge Großhans
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
- University of Basel, 4002 Basel, Switzerland
| | - Jordan D Ward
- Department of Molecular, Cell, and Developmental Biology, University of California-Santa Cruz, Santa Cruz, CA 95064, USA
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Park S, Noblett N, Pitts L, Colavita A, Wehman AM, Jin Y, Chisholm AD. Dopey-dependent regulation of extracellular vesicles maintains neuronal morphology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.07.591898. [PMID: 38766017 PMCID: PMC11100700 DOI: 10.1101/2024.05.07.591898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Mature neurons maintain their distinctive morphology for extended periods in adult life. Compared to developmental neurite outgrowth, axon guidance, and target selection, relatively little is known of mechanisms that maintain mature neuron morphology. Loss of function in C. elegans DIP-2, a member of the conserved lipid metabolic regulator Dip2 family, results in progressive overgrowth of neurites in adults. We find that dip-2 mutants display specific genetic interactions with sax-2, the C. elegans ortholog of Drosophila Furry and mammalian FRY. Combined loss of DIP-2 and SAX-2 results in severe disruption of neuronal morphology maintenance accompanied by increased release of neuronal extracellular vesicles (EVs). By screening for suppressors of dip-2 sax-2 double mutant defects we identified gain-of-function (gf) mutations in the conserved Dopey family protein PAD-1 and its associated phospholipid flippase TAT-5/ATP9A. In dip-2 sax-2 double mutants carrying either pad-1(gf) or tat-5(gf) mutation, EV release is reduced and neuronal morphology across multiple neuron types is restored to largely normal. PAD-1(gf) acts cell autonomously in neurons. The domain containing pad-1(gf) is essential for PAD-1 function, and PAD-1(gf) protein displays increased association with the plasma membrane and inhibits EV release. Our findings uncover a novel functional network of DIP-2, SAX-2, PAD-1, and TAT-5 that maintains morphology of neurons and other types of cells, shedding light on the mechanistic basis of neurological disorders involving human orthologs of these genes.
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Affiliation(s)
- Seungmee Park
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Nathaniel Noblett
- Neuroscience Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Lauren Pitts
- Department of Biological Sciences, University of Denver, Denver, CO 80208, USA
| | - Antonio Colavita
- Neuroscience Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Ann M Wehman
- Department of Biological Sciences, University of Denver, Denver, CO 80208, USA
| | - Yishi Jin
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Andrew D Chisholm
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
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Torzone SK, Breen PC, Cohen NR, Simmons KN, Dowen RH. The TWK-26 potassium channel governs nutrient absorption in the C. elegans intestine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592787. [PMID: 38766028 PMCID: PMC11100751 DOI: 10.1101/2024.05.06.592787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Ion channels are necessary for proper water and nutrient absorption in the intestine, which supports cellular metabolism and organismal growth. While a role for Na + co-transporters and pumps in intestinal nutrient absorption is well defined, how individual K + uniporters function to maintain ion homeostasis is poorly understood. Using Caenorhabditis elegans , we show that a gain-of-function mutation in twk-26 , which encodes a two-pore domain K + ion channel orthologous to human KCNK3, facilitates nutrient absorption and suppresses the metabolic and developmental defects displayed by impaired intestinal MAP Kinase (MAPK) signaling. Mutations in drl-1 and flr-4, which encode two components of this MAPK pathway, cause severe growth defects, reduced lipid storage, and a dramatic increase in autophagic lysosomes, which mirror dietary restriction phenotypes. Additionally, these MAPK mutants display structural defects of the intestine and an impaired defecation motor program. We find that activation of TWK-26 reverses the dietary restriction-like state of the MAPK mutants by restoring intestinal nutrient absorption without correcting the intestinal bloating or defecation defects. This study provides unique insight into the mechanisms by which intestinal K + ion channels support intestinal metabolic homeostasis.
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VanDerMolen KR, Newman MA, Breen PC, Huff LA, Dowen RH. Non-cell-autonomous regulation of mTORC2 by Hedgehog signaling maintains lipid homeostasis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592795. [PMID: 38766075 PMCID: PMC11100691 DOI: 10.1101/2024.05.06.592795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Organisms must appropriately allocate energetic resources between essential cellular processes to maintain homeostasis and in turn, maximize fitness. The nutritional and homeostatic regulators of energy homeostasis have been studied in detail; however, how developmental signals might impinge on these pathways to govern cellular metabolism is poorly understood. Here, we identify a non-canonical role for Hedgehog (Hh), a classic regulator of development, in maintaining intestinal lipid homeostasis in C. elegans . We find that expression of two Hh ligands, GRD-3 and GRD-4, is controlled by the LIN-29/EGR transcription factor in the hypodermis, where the Hh secretion factor CHE-14/Dispatched also facilitates non-cell autonomous Hh signaling. We demonstrate, using C. elegans and mouse hepatocytes, that Hh metabolic regulation does not occur through the canonical Hh transcription factor, TRA-1/GLI, but rather through non-canonical signaling that engages mTOR Complex 2 (mTORC2) in the intestine. Hh mutants display impaired lipid homeostasis, including reduced lipoprotein synthesis and fat accumulation, decreased growth, and upregulation of autophagy factors, mimicking loss of mTORC2. Additionally, we found that Hh inhibits p38 MAPK signaling in parallel to mTORC2 activation and that both pathways act together to modulate of lipid homeostasis. Our findings show a non-canonical role for Hedgehog signaling in lipid metabolism via regulation of core homeostatic pathways and reveal a new mechanism by which developmental timing events govern metabolic decisions.
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Hayden AN, Brandel KL, Merlau PR, Vijayakumar P, Leptich EJ, Pietryk EW, Gaytan ES, Ni CW, Chao HT, Rosenfeld JA, Arey RN. Behavioral screening of conserved RNA-binding proteins reveals CEY-1/YBX RNA-binding protein dysfunction leads to impairments in memory and cognition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.05.574402. [PMID: 38260399 PMCID: PMC10802296 DOI: 10.1101/2024.01.05.574402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
RNA-binding proteins (RBPs) regulate translation and plasticity which are required for memory. RBP dysfunction has been linked to a range of neurological disorders where cognitive impairments are a key symptom. However, of the 2,000 RBPs in the human genome, many are uncharacterized with regards to neurological phenotypes. To address this, we used the model organism C. elegans to assess the role of 20 conserved RBPs in memory. We identified eight previously uncharacterized memory regulators, three of which are in the C. elegans Y-Box (CEY) RBP family. Of these, we determined that cey-1 is the closest ortholog to the mammalian Y-Box (YBX) RBPs. We found that CEY-1 is both necessary in the nervous system for memory ability and sufficient to increase memory. Leveraging human datasets, we found both copy number variation losses and single nucleotide variants in YBX1 and YBX3 in individuals with neurological symptoms. We identified one predicted deleterious YBX3 variant of unknown significance, p.Asn127Tyr, in two individuals with neurological symptoms. Introducing this variant into endogenous cey-1 locus caused memory deficits in the worm. We further generated two humanized worm lines expressing human YBX3 or YBX1 at the cey-1 locus to test evolutionary conservation of YBXs in memory and the potential functional significance of the p.Asn127Tyr variant. Both YBX1/3 can functionally replace cey-1, and introduction of p.Asn127Tyr into the humanized YBX3 locus caused memory deficits. Our study highlights the worm as a model to reveal memory regulators and identifies YBX dysfunction as a potential new source of rare neurological disease.
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Affiliation(s)
- Ashley N Hayden
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
| | - Katie L Brandel
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
| | - Paul R Merlau
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
| | | | - Emily J Leptich
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
| | - Edward W Pietryk
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030
| | - Elizabeth S Gaytan
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
- Postbaccalaureate Research Education Program, Baylor College of Medicine, Houston, TX, 77030
| | - Connie W Ni
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
- Department of Neuroscience, Rice University, Houston, TX 77005
| | - Hsiao-Tuan Chao
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030
- Department of Pediatrics, Division of Neurology and Developmental Neuroscience, Baylor College of Medicine, Houston, TX, 77030
- Cain Pediatric Neurology Research Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, 77030
- McNair Medical Institute, The Robert and Janice McNair Foundation, Houston, TX, 77030
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030
- Baylor Genetics Laboratories, Houston, TX 77021
| | - Rachel N Arey
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX, 77030
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030
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Lamb H, Liro MJ, Myles KM, Fernholz M, Anderson HA, Rose LS. The Rac1 homolog CED-10 is a component of the MES-1/SRC-1 pathway for asymmetric division of the C. elegans EMS blastomere. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.04.588162. [PMID: 38645195 PMCID: PMC11030239 DOI: 10.1101/2024.04.04.588162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Asymmetric cell division is essential for the creation of cell types with different identities and functions. The EMS blastomere of the four-cell Caenorhabditis elegans embryo undergoes an asymmetric division in response to partially redundant signaling pathways. One pathway involves a Wnt signal emanating from the neighboring P2 cell, while the other pathway is defined by the receptor-like MES-1 protein localized at the EMS/P2 cell contact, and the cytoplasmic kinase SRC-1. In response to these pathways, the EMS nuclear-centrosome complex rotates so that the spindle forms on the anterior-posterior axis; after division, the daughter cell contacting P2 becomes the endodermal precursor cell. Here we identify the Rac1 homolog, CED-10, as a new component of the MES-1/SRC-1 pathway. Loss of CED-10 affects both spindle positioning and endoderm specification. Although MES-1 is still present at the EMS/P2 contact in ced-10 embryos, SRC-1 dependent phosphorylation is reduced. These and other results suggest that CED-10 acts downstream of MES-1 and upstream or at the level of SRC-1 activity. In addition, we find that the branched actin regulator ARX-2 is enriched at the EMS/P2 cell contact site, in a CED-10 dependent manner. Loss of ARX-2 results in spindle positioning defects, suggesting that CED-10 acts through branched actin to promote the asymmetric division of the EMS cell.
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Brar HK, Dey S, Singh P, Pande D, Ghosh-Roy A. Functional Recovery Associated with Dendrite Regeneration in PVD Neuron of Caenorhabditis elegans. eNeuro 2024; 11:ENEURO.0292-23.2024. [PMID: 38548333 PMCID: PMC7615967 DOI: 10.1523/eneuro.0292-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 02/18/2024] [Accepted: 03/03/2024] [Indexed: 05/02/2024] Open
Abstract
PVD neuron of Caenorhabditis elegans is a highly polarized cell with well-defined axonal, and dendritic compartments. PVD neuron operates in multiple sensory modalities including the control of both nociceptive touch sensation and body posture. Although both the axon and dendrites of this neuron show a regeneration response following laser-assisted injury, it is rather unclear how the behavior associated with this neuron is affected by the loss of these structures. It is also unclear whether neurite regrowth would lead to functional restoration in these neurons. Upon axotomy, using a femtosecond laser, we saw that harsh touch response was specifically affected leaving the body posture unperturbed. Subsequently, recovery in the touch response is highly correlated to the axon regrowth, which was dependent on DLK-1/MLK-1 MAP Kinase. Dendrotomy of both major and minor primary dendrites affected the wavelength and amplitude of sinusoidal movement without any apparent effect on harsh touch response. We further correlated the recovery in posture behavior to the type of dendrite regeneration events. We found that dendrite regeneration through the fusion and reconnection between the proximal and distal branches of the injured dendrite corresponded to improved recovery in posture. Our data revealed that the axons and dendrites of PVD neurons regulate the nociception and proprioception in worms, respectively. It also revealed that dendrite and axon regeneration lead to the restoration of these differential sensory modalities.
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Affiliation(s)
- Harjot Kaur Brar
- Department of Cellular and Molecular Neuroscience, National Brain Research Centre, Manesar 122052, Haryana, India
| | - Swagata Dey
- Department of Cellular and Molecular Neuroscience, National Brain Research Centre, Manesar 122052, Haryana, India
| | - Pallavi Singh
- Department of Cellular and Molecular Neuroscience, National Brain Research Centre, Manesar 122052, Haryana, India
| | - Devashish Pande
- Department of Cellular and Molecular Neuroscience, National Brain Research Centre, Manesar 122052, Haryana, India
| | - Anindya Ghosh-Roy
- Department of Cellular and Molecular Neuroscience, National Brain Research Centre, Manesar 122052, Haryana, India
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15
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Byrd DT, Han ZC, Piggott CA, Jin Y. PACS-1 variant protein is aberrantly localized in C. elegans model of PACS1/PACS2 syndromes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590644. [PMID: 38712144 PMCID: PMC11071410 DOI: 10.1101/2024.04.22.590644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
PACS (Phosphofurin Acidic Cluster Sorting Protein) proteins are known for their roles in sorting cargo proteins to organelles and can physically interact with WD40 repeat-containing protein WDR37. PACS1, PACS2, and WDR37 variants are associated with multisystemic syndromes and neurodevelopmental disorders characterized by intellectual disability, seizures, developmental delays, craniofacial abnormalities, and autism spectrum disorder. However, the effects of syndromic variants on function in vivo remains unknown. Here, we report the expression pattern of C. elegans orthologs of PACS and WDR37 and their interaction. We show that cePACS-1 and ceWDR-37 co-localize to somatic cytoplasm of many types of cells, and are mutually required for expression, supporting a conclusion that the intermolecular dependence of PACS1/PACS2/PACS-1 and WDR37/WDR-37 is evolutionarily conserved. We further show that editing in PACS1 and PACS2 variants in cePACS-1 changes protein localization in multiple cell types, including neurons. Moreover, expression of human PACS1 can functionally complement C. elegans PACS-1 in neurons, demonstrating conserved functions of the PACS-WDR37 axis in an invertebrate model system. Our findings reveal effects of human variants and suggest potential strategies to identify regulatory network components that may contribute to understanding molecular underpinnings of PACS/WDR37 syndromes.
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Wu Z, Cardona EA, Pierce JT. Non-apoptotic role of EGL-1 in exopher production and neuronal health in Caenorhabditis elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590348. [PMID: 38712027 PMCID: PMC11071422 DOI: 10.1101/2024.04.19.590348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
While traditionally studied for their pro-apoptotic functions, recent research suggests BH3-only proteins also have non-apoptotic roles. Here, we find that EGL-1, the BH3-only protein in Caenorhabditis elegans , promotes the cell-autonomous production of exophers in adult neurons. Exophers are large, micron-scale vesicles that are ejected from the cell and contain cellular components such as mitochondria. EGL-1 facilitates exopher production potentially through regulation of mitochondrial dynamics. Moreover, an endogenous, low level of EGL-1 expression appears to benefit dendritic health. Our findings provide insights into the mechanistic role of BH3-only protein in mitochondrial dynamics, downstream exopher production, and ultimately neuronal health. Significance statement BH3-only proteins were known for their function in inducing cell death. Their presence in healthy adult neurons, however, suggests additional roles. Our study focused on the BH3-only protein EGL-1 in the nematode Caenorhabditis elegans , where its apoptotic role was discovered. We reveal a new role in cell-autonomously promoting exopher production - a process where neurons extrude large vesicles containing potentially harmful cell contents. EGL-1 appears to promote this by regulating mitochondrial dynamics. We also report that low levels of EGL-1 benefit neuronal health and function. These findings expand our understanding of BH3-only proteins, mitochondrial dynamics, and exopher production in neurons and provide insights for neurodegenerative diseases.
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Breen PC, Kanakanui KG, Newman MA, Dowen RH. The F-box protein FBXL-5 governs vitellogenesis and lipid homeostasis in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.18.590113. [PMID: 38712300 PMCID: PMC11071313 DOI: 10.1101/2024.04.18.590113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
The molecular mechanisms that govern the metabolic commitment to reproduction, which often occurs at the expense of somatic reserves, remain poorly understood. We identified the C. elegans F-box protein FBXL-5 as a negative regulator of maternal provisioning of vitellogenin lipoproteins, which mediate the transfer of intestinal lipids to the germline. Mutations in fbxl-5 partially suppress the vitellogenesis defects observed in the heterochronic mutants lin-4 and lin-29, both of which ectopically express fbxl-5 at the adult developmental stage. FBXL-5 functions in the intestine to negatively regulate expression of the vitellogenin genes; and consistently, intestine-specific over-expression of FBXL-5 is sufficient to inhibit vitellogenesis, restrict lipid accumulation, and shorten lifespan. Our epistasis analyses suggest that fbxl-5 functions in concert with cul-6 , a cullin gene, and the Skp1-related gene skr-3 to regulate vitellogenesis. Additionally, fbxl-5 acts genetically upstream of rict-1 , which encodes the core mTORC2 protein Rictor, to govern vitellogenesis. Together, our results reveal an unexpected role for a SCF ubiquitin-ligase complex in controlling intestinal lipid homeostasis by engaging mTORC2 signaling.
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Sandhu A, Lyu X, Wan X, Meng X, Tang NH, Gonzalez G, Syed IN, Chen L, Jin Y, Chisholm AD. The microtubule regulator EFA-6 forms spatially restricted cortical foci dependent on its intrinsically disordered region and interactions with tubulins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.14.588158. [PMID: 38645057 PMCID: PMC11030407 DOI: 10.1101/2024.04.14.588158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Microtubules (MTs) are dynamic components of the cytoskeleton and play essential roles in morphogenesis and maintenance of tissue and cell integrity. Despite recent advances in understanding MT ultrastructure, organization, and growth control, how cells regulate MT organization at the cell cortex remains poorly understood. The EFA-6/EFA6 proteins are recently identified membrane-associated proteins that inhibit cortical MT dynamics. Here, combining visualization of endogenously tagged C. elegans EFA-6 with genetic screening, we uncovered tubulin-dependent regulation of EFA-6 patterning. In the mature epidermal epithelium, EFA-6 forms punctate foci in specific regions of the apical cortex, dependent on its intrinsically disordered region (IDR). We further show the EFA-6 IDR is sufficient to form biomolecular condensates in vitro. In screens for mutants with altered GFP::EFA-6 localization, we identified a novel gain-of-function (gf) mutation in an α-tubulin tba-1 that induces ectopic EFA-6 foci in multiple cell types. tba-1(gf) animals exhibit temperature-sensitive embryonic lethality, which is partially suppressed by efa-6(lf), indicating the interaction between tubulins and EFA-6 is important for normal development. TBA-1(gf) shows reduced incorporation into filamentous MTs but has otherwise mild effects on cellular MT organization. The ability of TBA-1(gf) to trigger ectopic EFA-6 foci formation requires β-tubulin TBB-2 and the chaperon EVL-20/Arl2. The tba-1(gf)-induced EFA-6 foci display slower turnover, contain the MT-associated protein TAC-1/TACC, and require the EFA-6 MTED. Our results reveal a novel crosstalk between cellular tubulins and cortical MT regulators in vivo.
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Affiliation(s)
- Anjali Sandhu
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Xiaohui Lyu
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Xinghaoyun Wan
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Xuefeng Meng
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Ngang Heok Tang
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Gilberto Gonzalez
- Barshop Institute for Longevity and Aging Studies, Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Ishana N. Syed
- Barshop Institute for Longevity and Aging Studies, Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Lizhen Chen
- Barshop Institute for Longevity and Aging Studies, Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Yishi Jin
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
| | - Andrew D. Chisholm
- Department of Neurobiology, School of Biological Sciences, University of California San Diego, CA 92093 USA
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California San Diego, CA 92093 USA
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Salcedo-Tacuma D, Asad N, Howells G, Anderson R, Smith DM. Proteasome hyperactivation rewires the proteome enhancing stress resistance, proteostasis, lipid metabolism and ERAD in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.04.588128. [PMID: 38617285 PMCID: PMC11014606 DOI: 10.1101/2024.04.04.588128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Proteasome dysfunction is implicated in the pathogenesis of neurodegenerative diseases and age-related proteinopathies. Using a C. elegans model, we demonstrate that 20S proteasome hyperactivation, facilitated by 20S gate-opening, accelerates the targeting of intrinsically disordered proteins. This leads to increased protein synthesis, extensive rewiring of the proteome and transcriptome, enhanced oxidative stress defense, accelerated lipid metabolism, and peroxisome proliferation. It also promotes ER-associated degradation (ERAD) of aggregation-prone proteins, such as alpha-1 antitrypsin (ATZ) and various lipoproteins. Notably, our results reveal that 20S proteasome hyperactivation suggests a novel role in ERAD with broad implications for proteostasis-related disorders, simultaneously affecting lipid homeostasis and peroxisome proliferation. Furthermore, the enhanced cellular capacity to mitigate proteostasis challenges, alongside unanticipated acceleration of lipid metabolism is expected to contribute to the longevity phenotype of this mutant. Remarkably, the mechanism of longevity induced by 20S gate opening appears unique, independent of known longevity and stress-resistance pathways. These results support the therapeutic potential of 20S proteasome activation in mitigating proteostasis-related disorders broadly and provide new insights into the complex interplay between proteasome activity, cellular health, and aging.
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Affiliation(s)
- David Salcedo-Tacuma
- Department of Biochemistry and Molecular Medicine, West Virginia University School of Medicine, 4 Medical Center Dr., Morgantown, WV USA
| | - Nadeeem. Asad
- Department of Biochemistry and Molecular Medicine, West Virginia University School of Medicine, 4 Medical Center Dr., Morgantown, WV USA
| | - Giovanni Howells
- Department of Biochemistry and Molecular Medicine, West Virginia University School of Medicine, 4 Medical Center Dr., Morgantown, WV USA
| | - Raymond Anderson
- Department of Biochemistry and Molecular Medicine, West Virginia University School of Medicine, 4 Medical Center Dr., Morgantown, WV USA
| | - David M. Smith
- Department of Biochemistry and Molecular Medicine, West Virginia University School of Medicine, 4 Medical Center Dr., Morgantown, WV USA
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, USA
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20
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Kimmich MJ, Sundaramurthy S, Geary MA, Lesanpezeshki L, Yingling CV, Vanapalli SA, Littlefield RS, Pruyne D. FHOD-1/profilin-mediated actin assembly protects sarcomeres against contraction-induced deformation in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.29.582848. [PMID: 38559004 PMCID: PMC10979920 DOI: 10.1101/2024.02.29.582848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Formin HOmology Domain 2-containing (FHOD) proteins are a subfamily of actin-organizing formins important for striated muscle development in many animals. We showed previously that absence of the sole FHOD protein, FHOD-1, from C. elegans results in thin body-wall muscles with misshapen dense bodies that serve as sarcomere Z-lines. We demonstrate here that actin polymerization by FHOD-1 is required for its function in muscle development, and that FHOD-1 cooperates with profilin PFN-3 for dense body morphogenesis, and profilins PFN-2 and PFN-3 to promote body-wall muscle growth. We further demonstrate dense bodies in fhod-1 and pfn-3 mutants are less stable than in wild type animals, having a higher proportion of dynamic protein, and becoming distorted by prolonged muscle contraction. We also observe accumulation of actin depolymerization factor/cofilin homolog UNC-60B in body-wall muscle of these mutants. Such accumulations may indicate targeted disassembly of thin filaments dislodged from unstable dense bodies, and may account for the abnormally slow growth and reduced strength of body-wall muscle in fhod-1 mutants. Overall, these results show the importance of FHOD protein-mediated actin assembly to forming stable sarcomere Z-lines, and identify profilin as a new contributor to FHOD activity in striated muscle development.
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Affiliation(s)
- Michael J. Kimmich
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210
| | - Sumana Sundaramurthy
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210
| | - Meaghan A. Geary
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210
| | - Leila Lesanpezeshki
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409
| | - Curtis V. Yingling
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210
| | - Siva A. Vanapalli
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409
| | | | - David Pruyne
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210
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21
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Tollervey F, Rios MU, Zagoriy E, Woodruff JB, Mahamid J. Native molecular architectures of centrosomes in C. elegans embryos. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.03.587742. [PMID: 38617234 PMCID: PMC11014625 DOI: 10.1101/2024.04.03.587742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Centrosomes organize microtubules that are essential for mitotic divisions in animal cells. They consist of centrioles surrounded by Pericentriolar Material (PCM). Questions related to mechanisms of centriole assembly, PCM organization, and microtubule formation remain unanswered, in part due to limited availability of molecular-resolution structural analyses in situ. Here, we use cryo-electron tomography to visualize centrosomes across the cell cycle in cells isolated from C. elegans embryos. We describe a pseudo-timeline of centriole assembly and identify distinct structural features including a cartwheel in daughter centrioles, and incomplete microtubule doublets surrounded by a star-shaped density in mother centrioles. We find that centriole and PCM microtubules differ in protofilament number (13 versus 11) indicating distinct nucleation mechanisms. This difference could be explained by atypical γ-tubulin ring complexes with 11-fold symmetry identified at the minus ends of short PCM microtubules. We further characterize a porous and disordered network that forms the interconnected PCM. Thus, our work builds a three-dimensional structural atlas that helps explain how centrosomes assemble, grow, and achieve function.
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Affiliation(s)
- Fergus Tollervey
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
- Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Manolo U. Rios
- Department of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Evgenia Zagoriy
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Jeffrey B. Woodruff
- Department of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Julia Mahamid
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
- Cell Biology and Biophysics Unit, EMBL, 69117 Heidelberg, Germany
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22
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Gharat V, Peter F, de Quervain DJF, Papassotiropoulos A, Stetak A. Role of GLR-1 in Age-Dependent Short-Term Memory Decline. eNeuro 2024; 11:ENEURO.0420-23.2024. [PMID: 38519128 PMCID: PMC11005081 DOI: 10.1523/eneuro.0420-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 02/10/2024] [Accepted: 03/06/2024] [Indexed: 03/24/2024] Open
Abstract
As the global elderly population grows, age-related cognitive decline is becoming an increasingly significant healthcare issue, often leading to various neuropsychiatric disorders. Among the many molecular players involved in memory, AMPA-type glutamate receptors are known to regulate learning and memory, but how their dynamics change with age and affect memory decline is not well understood. Here, we examined the in vivo properties of the AMPA-type glutamate receptor GLR-1 in the AVA interneuron of the Caenorhabditis elegans nervous system during physiological aging. We found that both total and membrane-bound GLR-1 receptor levels decrease with age in wild-type worms, regardless of their location along the axon. Using fluorescence recovery after photobleaching, we also demonstrated that a reduction in GLR-1 abundance correlates with decreased local, synaptic GLR-1 receptor dynamics. Importantly, we found that reduced GLR-1 levels strongly correlate with the age-related decline in short-term associative memory. Genetic manipulation of GLR-1 stability, by either deleting msi-1 or expressing a ubiquitination-defective GLR-1 (4KR) variant, prevented this age-related reduction in receptor abundance and improved the short-term memory performance in older animals, which reached performance levels similar to those of young animals. Overall, our data indicate that AMPA-type glutamate receptor abundance and dynamics are key factors in maintaining memory function and that changes in these parameters are linked to age-dependent short-term memory decline.
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Affiliation(s)
- Vaibhav Gharat
- Division of Molecular Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel 4055, Switzerland
| | - Fabian Peter
- Division of Molecular Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel 4055, Switzerland
| | - Dominique J-F de Quervain
- Division of Molecular Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- Division of Cognitive Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- University Psychiatric Clinics, University of Basel, Basel 4002, Switzerland
| | - Andreas Papassotiropoulos
- Division of Molecular Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel 4055, Switzerland
- University Psychiatric Clinics, University of Basel, Basel 4002, Switzerland
| | - Attila Stetak
- Division of Molecular Neuroscience, Department of Biomedicine, University of Basel, Basel 4055, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel 4055, Switzerland
- University Psychiatric Clinics, University of Basel, Basel 4002, Switzerland
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23
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Ulaganathan G, Jiang H, Canio N, Oke A, Armstrong SS, Abrahamsson D, Varshavsky JR, Lam J, Cooper C, Robinson JF, Fung JC, Woodruff TJ, Allard P. Screening and characterization of 133 physiologically-relevant environmental chemicals for reproductive toxicity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.22.584808. [PMID: 38585844 PMCID: PMC10996516 DOI: 10.1101/2024.03.22.584808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Reproduction is a functional outcome that relies on complex cellular, tissue, and organ interactions that span the developmental period to adulthood. Thus, the assessment of its disruption by environmental chemicals is remarkably painstaking in conventional toxicological animal models and does not scale up to the number of chemicals present in our environment and requiring testing. We adapted a previously described low-throughput in vivo chromosome segregation assay using C. elegans predictive of reproductive toxicity and leveraged available public data sources (ToxCast, ICE) to screen and characterize 133 physiologically-relevant chemicals in a high-throughput manner. The screening outcome was further validated in a second, independent in vivo assay assessing embryonic viability. In total, 13 chemicals were classified as reproductive toxicants with the two most active chemicals belonging to the large family of Quaternary Ammonium Compounds (QACs) commonly used as disinfectants but with limited available reproductive toxicity data. We compared the results from the C. elegans assay with ToxCast in vitro data compiled from 700+ cell response assays and 300+ signaling pathways-based assays. We did not observe a difference in the bioactivity or in average potency (AC50) between the top and bottom chemicals. However, the intended target categories were significantly different between the classified chemicals with, in particular, an over-representation of steroid hormone targets for the high Z-score chemicals. Taken together, these results point to the value of in vivo models that scale to high-throughput level for reproductive toxicity assessment and to the need to prioritize the assessment of QACs impacts on reproduction.
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24
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Rathor L, Curry S, Park Y, McElroy T, Robles B, Sheng Y, Chen WW, Min K, Xiao R, Lee MH, Han SM. Mitochondrial stress in GABAergic neurons non-cell autonomously regulates organismal health and aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.20.585932. [PMID: 38585797 PMCID: PMC10996468 DOI: 10.1101/2024.03.20.585932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Mitochondrial stress within the nervous system can trigger non-cell autonomous responses in peripheral tissues. However, the specific neurons involved and their impact on organismal aging and health have remained incompletely understood. Here, we demonstrate that mitochondrial stress in γ-aminobutyric acid-producing (GABAergic) neurons in Caenorhabditis elegans ( C. elegans ) is sufficient to significantly alter organismal lifespan, stress tolerance, and reproductive capabilities. This mitochondrial stress also leads to significant changes in mitochondrial mass, energy production, and levels of reactive oxygen species (ROS). DAF-16/FoxO activity is enhanced by GABAergic neuronal mitochondrial stress and mediates the induction of these non-cell-autonomous effects. Moreover, our findings indicate that GABA signaling operates within the same pathway as mitochondrial stress in GABAergic neurons, resulting in non-cell-autonomous alterations in organismal stress tolerance and longevity. In summary, these data suggest the crucial role of GABAergic neurons in detecting mitochondrial stress and orchestrating non-cell-autonomous changes throughout the organism.
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25
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Zhang MG, Seyedolmohadesin M, Hawk S, Park H, Finnen N, Schroeder F, Venkatachalam V, Sternberg PW. Sensory integration of food availability and population density during the diapause exit decision involves insulin-like signaling in Caenorhabditis elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.20.586022. [PMID: 38586049 PMCID: PMC10996498 DOI: 10.1101/2024.03.20.586022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Decisions made over long time scales, such as life cycle decisions, require coordinated interplay between sensory perception and sustained gene expression. The Caenorhabditis elegans dauer (or diapause) exit developmental decision requires sensory integration of population density and food availability to induce an all-or-nothing organismal-wide response, but the mechanism by which this occurs remains unknown. Here, we demonstrate how the ASJ chemosensory neurons, known to be critical for dauer exit, perform sensory integration at both the levels of gene expression and calcium activity. In response to favorable conditions, dauers rapidly produce and secrete the dauer exit-promoting insulin-like peptide INS-6. Expression of ins-6 in the ASJ neurons integrate population density and food level and can reflect decision commitment since dauers committed to exiting have higher ins-6 expression levels than those of non-committed dauers. Calcium imaging in dauers reveals that the ASJ neurons are activated by food, and this activity is suppressed by pheromone, indicating that sensory integration also occurs at the level of calcium transients. We find that ins-6 expression in the ASJ neurons depends on neuronal activity in the ASJs, cGMP signaling, a CaM-kinase pathway, and the pheromone components ascr#8 and ascr#2. We propose a model in which decision commitment to exit the dauer state involves an autoregulatory feedback loop in the ASJ neurons that promotes high INS-6 production and secretion. These results collectively demonstrate how insulin-like peptide signaling helps animals compute long-term decisions by bridging sensory perception to decision execution.
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Affiliation(s)
- Mark G Zhang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | | | - Soraya Hawk
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Heenam Park
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Nerissa Finnen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Frank Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | | | - Paul W Sternberg
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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Vassallo BG, Scheidel N, Fischer SEJ, Kim DH. Bacteria Are a Major Determinant of Orsay Virus Transmission and Infection in Caenorhabditis elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.05.556377. [PMID: 37732241 PMCID: PMC10508782 DOI: 10.1101/2023.09.05.556377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
The microbiota is a key determinant of the physiology and immunity of animal hosts. The factors governing the transmissibility of viruses between susceptible hosts are incompletely understood. Bacteria serve as food for Caenorhabditis elegans and represent an integral part of the natural environment of C. elegans. We determined the effects of bacteria isolated with C. elegans from its natural environment on the transmission of Orsay virus in C. elegans using quantitative virus transmission and host susceptibility assays. We observed that Ochrobactrum species promoted Orsay virus transmission, whereas Pseudomonas lurida MYb11 attenuated virus transmission relative to the standard laboratory bacterial food Escherichia coli OP50. We found that pathogenic Pseudomonas aeruginosa strains PA01 and PA14 further attenuated virus transmission. We determined that the amount of Orsay virus required to infect 50% of a C. elegans population on P. lurida MYb11 compared with Ochrobactrum vermis MYb71 was dramatically increased, over three orders of magnitude. Host susceptibility was attenuated even further in presence of P. aeruginosa PA14. Genetic analysis of the determinants of P. aeruginosa required for attenuation of C. elegans susceptibility to Orsay virus infection revealed a role for regulators of quorum sensing. Our data suggest that distinct constituents of the C. elegans microbiota and potential pathogens can have widely divergent effects on Orsay virus transmission, such that associated bacteria can effectively determine host susceptibility versus resistance to viral infection. Our study provides quantitative evidence for a critical role for tripartite host-virus-bacteria interactions in determining the transmissibility of viruses among susceptible hosts.
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Snow S, Mir D, Ma Z, Horrocks J, Cox M, Ruzga M, Sayed H, Rogers AN. Neuronal CBP-1 is required for enhanced body muscle proteostasis in response to reduced translation downstream of mTOR. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.15.585263. [PMID: 38559178 PMCID: PMC10980069 DOI: 10.1101/2024.03.15.585263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Background The ability to maintain muscle function decreases with age and loss of proteostatic function. Diet, drugs, and genetic interventions that restrict nutrients or nutrient signaling help preserve long-term muscle function and slow age-related decline. Previously, it was shown that attenuating protein synthesis downstream of the mechanistic target of rapamycin (mTOR) gradually increases expression of heat shock response (HSR) genes in a manner that correlates with increased resilience to protein unfolding stress. Here, we investigate the role of specific tissues in mediating the cytoprotective effects of low translation. Methods This study uses genetic tools (transgenic C. elegans , RNA interference and gene expression analysis) as well as physiological assays (survival and paralysis assays) in order to better understand how specific tissues contribute to adaptive changes involving cellular cross-talk that enhance proteostasis under low translation conditions. Results We use the C. elegans system to show that lowering translation in neurons or the germline increases heat shock gene expression and survival under conditions of heat stress. In addition, we find that low translation in these tissues protects motility in a body muscle-specific model of proteotoxicity that results in paralysis. Low translation in neurons or germline also results in increased expression of certain muscle regulatory and structural genes, reversing reduced expression normally observed with aging in C. elegans . Enhanced resilience to protein unfolding stress requires neuronal expression of cbp-1 . Conclusion Low translation in either neurons or the germline orchestrate protective adaptation in other tissues, including body muscle.
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Duangjan C, Chang X, Seidler PM, Curran SP. Oolonghomobisflavans from Camellia sinensis disaggregate tau fibrils across Alzheimer's disease models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.26.582120. [PMID: 38464186 PMCID: PMC10925199 DOI: 10.1101/2024.02.26.582120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Alzheimer's disease (AD) is a common debilitating neurodegenerative disease with limited treatment options. Amyloid-β (Aβ) and tau fibrils are well-established hallmarks of AD, which can induce oxidative stress, neuronal cell death, and are linked to disease pathology. Here, we describe the effects of Oolonghomobisflavan A (OFA) and Oolonghomobisflavan B (OFB) on tau fibril disaggregation and prionogenic seeding. Transcriptomic analysis of OF-treated animals reveals the induction of a proteostasis-enhancing and health-promoting signature. OFA treatment reduced the burden of Tau protein aggregation in a C. elegans model expressing pathogenic human tau ("hTau-expressing") and promoted Tau disaggregation and inhibited seeding in assays using ex vivo brain-derived paired helical filament tau protein fibrils from Alzheimer's disease brain donors. Correspondingly, treatment with OF improved multiple fitness and aging-related health parameters in the hTau-expressing C. elegans model, including reproductive output, muscle function, and importantly, reversed the shortened lifespan stemming from pathogenic Tau expression. Collectively, this study provides new evidence supporting the neuroprotective effects of OFs and reveal a new therapeutic strategy for targeting AD and other neurodegenerative diseases characterized by tauopathy.
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Sharifian Gh. M, Norouzi F, Sorci M, Zaid TS, Pier GB, Achimovich A, Ongwae GM, Liang B, Ryan M, Lemke M, Belfort G, Gadjeva M, Gahlmann A, Pires MM, Venter H, Harris TE, Laurie GW. Targeting Iron - Respiratory Reciprocity Promotes Bacterial Death. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.01.582947. [PMID: 38464199 PMCID: PMC10925246 DOI: 10.1101/2024.03.01.582947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Discovering new bacterial signaling pathways offers unique antibiotic strategies. Here, through an unbiased resistance screen of 3,884 gene knockout strains, we uncovered a previously unknown non-lytic bactericidal mechanism that sequentially couples three transporters and downstream transcription to lethally suppress respiration of the highly virulent P. aeruginosa strain PA14 - one of three species on the WHO's 'Priority 1: Critical' list. By targeting outer membrane YaiW, cationic lacritin peptide 'N-104' translocates into the periplasm where it ligates outer loops 4 and 2 of the inner membrane transporters FeoB and PotH, respectively, to suppress both ferrous iron and polyamine uptake. This broadly shuts down transcription of many biofilm-associated genes, including ferrous iron-dependent TauD and ExbB1. The mechanism is innate to the surface of the eye and is enhanced by synergistic coupling with thrombin peptide GKY20. This is the first example of an inhibitor of multiple bacterial transporters.
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Affiliation(s)
| | - Fatemeh Norouzi
- Department of Cell Biology, University of Virginia, Charlottesville VA, USA
| | - Mirco Sorci
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy NY, USA
| | - Tanweer S Zaid
- Division of Infectious Disease, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston MA
| | - Gerald B. Pier
- Division of Infectious Disease, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston MA
| | - Alecia Achimovich
- Department of Chemistry, University of Virginia, Charlottesville VA, USA
| | - George M. Ongwae
- Department of Chemistry, University of Virginia, Charlottesville VA, USA
| | - Binyong Liang
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville VA, USA
| | - Margaret Ryan
- Department of Cell Biology, University of Virginia, Charlottesville VA, USA
| | - Michael Lemke
- Department of Pharmacology, University of Virginia, Charlottesville VA, USA
| | - Georges Belfort
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy NY, USA
| | - Mihaela Gadjeva
- Division of Infectious Disease, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston MA
| | - Andreas Gahlmann
- Department of Chemistry, University of Virginia, Charlottesville VA, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville VA, USA
| | - Henrietta Venter
- Sansom Institute for Health Research, University of South Australia, Adelaide, Australia
| | - Thurl E. Harris
- Department of Pharmacology, University of Virginia, Charlottesville VA, USA
| | - Gordon W. Laurie
- Department of Cell Biology, University of Virginia, Charlottesville VA, USA
- Department of Ophthalmology, University of Virginia, Charlottesville VA, USA
- Department of Biomedical Engineering, University of Virginia, Charlottesville VA, USA
- Contact author: Gordon Laurie
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Tse-Kang S, Wani KA, Peterson ND, Page A, Pukkila-Worley R. Activation of intestinal immunity by pathogen effector-triggered aggregation of lysosomal TIR-1/SARM1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.04.569946. [PMID: 38106043 PMCID: PMC10723332 DOI: 10.1101/2023.12.04.569946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
TIR-domain proteins with enzymatic activity are essential for immunity in plants, animals, and bacteria. However, it is not known how these proteins function in pathogen sensing in animals. We discovered that a TIR-domain protein (TIR-1/SARM1) is strategically expressed on the membranes of a lysosomal sub-compartment, which enables intestinal epithelial cells in the nematode C. elegans to survey for pathogen effector-triggered host damage. We showed that a redox active virulence effector secreted by the bacterial pathogen Pseudomonas aeruginosa alkalinized and condensed a specific subset of lysosomes by inducing intracellular oxidative stress. Concentration of TIR-1/SARM1 on the surface of these organelles triggered its multimerization, which engages its intrinsic NADase activity, to activate the p38 innate immune pathway and protect the host against microbial intoxication. Thus, lysosomal TIR-1/SARM1 is a sensor for oxidative stress induced by pathogenic bacteria to activate metazoan intestinal immunity.
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Power KM, Nguyen KC, Silva A, Singh S, Hall DH, Rongo C, Barr MM. NEKL-4 regulates microtubule stability and mitochondrial health in C. elegans ciliated neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580304. [PMID: 38405845 PMCID: PMC10888866 DOI: 10.1101/2024.02.14.580304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Ciliopathies are often caused by defects in the ciliary microtubule core. Glutamylation is abundant in cilia, and its dysregulation may contribute to ciliopathies and neurodegeneration. Mutation of the deglutamylase CCP1 causes infantile-onset neurodegeneration. In C. elegans, ccpp-1 loss causes age-related ciliary degradation that is suppressed by mutation in the conserved NEK10 homolog nekl-4. NEKL-4 is absent from cilia, yet negatively regulates ciliary stability via an unknown, glutamylation-independent mechanism. We show that NEKL-4 was mitochondria-associated. nekl-4 mutants had longer mitochondria, a higher baseline mitochondrial oxidation state, and suppressed ccpp-1 mutant lifespan extension in response to oxidative stress. A kinase-dead nekl-4(KD) mutant ectopically localized to ccpp-1 cilia and rescued degenerating microtubule doublet B-tubules. A nondegradable nekl-4(PESTΔ) mutant resembled the ccpp-1 mutant with dye filling defects and B-tubule breaks. The nekl-4(PESTΔ) Dyf phenotype was suppressed by mutation in the depolymerizing kinesin-8 KLP-13/KIF19A. We conclude that NEKL-4 influences ciliary stability by activating ciliary kinesins and promoting mitochondrial homeostasis.
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Affiliation(s)
- Kaiden M Power
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, United States of America
| | - Ken C Nguyen
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, Bronx, NY, United States of America
| | - Andriele Silva
- Department of Biology, Brooklyn College of the City University of New York, Brooklyn, NY, United States of America
| | - Shaneen Singh
- Department of Biology, Brooklyn College of the City University of New York, Brooklyn, NY, United States of America
| | - David H Hall
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, Bronx, NY, United States of America
| | - Christopher Rongo
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, United States of America
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, United States of America
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Correa E, Mialon M, Cizeron M, Bessereau JL, Pinan-Lucarre B, Kratsios P. UNC-30/PITX coordinates neurotransmitter identity with postsynaptic GABA receptor clustering. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580278. [PMID: 38405977 PMCID: PMC10888783 DOI: 10.1101/2024.02.14.580278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Terminal selectors are transcription factors that control neuronal identity by regulating the expression of key effector molecules, such as neurotransmitter (NT) biosynthesis proteins, ion channels and neuropeptides. Whether and how terminal selectors control neuronal connectivity is poorly understood. Here, we report that UNC-30 (PITX2/3), the terminal selector of GABA motor neuron identity in C. elegans , is required for NT receptor clustering, a hallmark of postsynaptic differentiation. Animals lacking unc-30 or madd-4B, the short isoform of the MN-secreted synapse organizer madd-4 ( Punctin/ADAMTSL ), display severe GABA receptor type A (GABA A R) clustering defects in postsynaptic muscle cells. Mechanistically, UNC-30 acts directly to induce and maintain transcription of madd-4B and GABA biosynthesis genes (e.g., unc-25/GAD , unc-47/VGAT ). Hence, UNC-30 controls GABA A R clustering on postsynaptic muscle cells and GABA biosynthesis in presynaptic cells, transcriptionally coordinating two critical processes for GABA neurotransmission. Further, we uncover multiple target genes and a dual role for UNC-30 both as an activator and repressor of gene transcription. Our findings on UNC-30 function may contribute to our molecular understanding of human conditions, such as Axenfeld-Rieger syndrome, caused by PITX2 and PITX3 gene mutations.
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Lee HJ, Liang J, Chaudhary S, Moon S, Yu Z, Wu T, Liu H, Choi MK, Zhang Y, Lu H. Automated cell annotation in multi-cell images using an improved CRF_ID algorithm. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.07.543949. [PMID: 37333322 PMCID: PMC10274780 DOI: 10.1101/2023.06.07.543949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Cell identification is an important yet difficult process in data analysis of biological images. Previously, we developed an automated cell identification method called CRF_ID and demonstrated its high performance in C. elegans whole-brain images (Chaudhary et al, 2021). However, because the method was optimized for whole-brain imaging, comparable performance could not be guaranteed for application in commonly used C. elegans multi-cell images that display a subpopulation of cells. Here, we present an advance CRF_ID 2.0 that expands the generalizability of the method to multi-cell imaging beyond whole-brain imaging. To illustrate the application of the advance, we show the characterization of CRF_ID 2.0 in multi-cell imaging and cell-specific gene expression analysis in C. elegans. This work demonstrates that high accuracy automated cell annotation in multi-cell imaging can expedite cell identification and reduce its subjectivity in C. elegans and potentially other biological images of various origins.
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Affiliation(s)
- Hyun Jee Lee
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, United States
| | - Jingting Liang
- Department of Organismic and Evolutionary Biology, Harvard University, United States
| | - Shivesh Chaudhary
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, United States
| | - Sihoon Moon
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, United States
| | - Zikai Yu
- Interdisciplinary BioEngineering Program, Georgia Institute of Technology, United States
| | - Taihong Wu
- Department of Organismic and Evolutionary Biology, Harvard University, United States
| | - He Liu
- Department of Organismic and Evolutionary Biology, Harvard University, United States
- Present address: Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Myung-Kyu Choi
- Department of Organismic and Evolutionary Biology, Harvard University, United States
| | - Yun Zhang
- Department of Organismic and Evolutionary Biology, Harvard University, United States
- Center for Brain Science, Harvard University, United States
| | - Hang Lu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, United States
- Interdisciplinary BioEngineering Program, Georgia Institute of Technology, United States
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Ji H, Chen D, Fang-Yen C. Automated multimodal imaging of Caenorhabditis elegans behavior in multi-well plates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.09.579675. [PMID: 38405855 PMCID: PMC10888940 DOI: 10.1101/2024.02.09.579675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Large-scale assays of behavior in model organisms play an important role in genetic screens, drug testing, and the elucidation of gene-behavior relationships. We have developed an automated, high-throughput imaging and analysis method for assaying behaviors of the nematode C. elegans . We use high-resolution optical imaging to longitudinally record the behaviors of 96 animals at a time in multi-well plates, and computer vision software to quantify the animals' locomotor activity, behavioral states, and egg laying events. To demonstrate the capabilities of our system we used it to examine the role of serotonin in C. elegans behavior. We found that egg-laying events are preceded by a period of reduced locomotion, and that this decline in movement requires serotonin signaling. In addition, we identified novel roles of serotonin receptors SER-1 and SER-7 in regulating the effects of serotonin on egg laying across roaming, dwelling, and quiescent locomotor states. Our system will be useful for performing genetic or chemical screens for modulators of behavior.
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Buckley M, Jacob WP, Bortey L, McClain M, Ritter AL, Godfrey A, Munneke AS, Ramachandran S, Kenis S, Kolnik JC, Olofsson S, Adkins R, Kutoloski T, Rademacher L, Heinecke O, Alva A, Beets I, Francis MM, Kowalski JR. Cell non-autonomous signaling through the conserved C. elegans glycopeptide hormone receptor FSHR-1 regulates cholinergic neurotransmission. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.10.578699. [PMID: 38405708 PMCID: PMC10888917 DOI: 10.1101/2024.02.10.578699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Modulation of neurotransmission is key for organismal responses to varying physiological contexts such as during infection, injury, or other stresses, as well as in learning and memory and for sensory adaptation. Roles for cell autonomous neuromodulatory mechanisms in these processes have been well described. The importance of cell non-autonomous pathways for inter-tissue signaling, such as gut-to-brain or glia-to-neuron, has emerged more recently, but the cellular mechanisms mediating such regulation remain comparatively unexplored. Glycoproteins and their G protein-coupled receptors (GPCRs) are well-established orchestrators of multi-tissue signaling events that govern diverse physiological processes through both cell-autonomous and cell non-autonomous regulation. Here, we show that follicle stimulating hormone receptor, FSHR-1, the sole Caenorhabditis elegans ortholog of mammalian glycoprotein hormone GPCRs, is important for cell non-autonomous modulation of synaptic transmission. Inhibition of fshr-1 expression reduces muscle contraction and leads to synaptic vesicle accumulation in cholinergic motor neurons. The neuromuscular and locomotor defects in fshr-1 loss-of-function mutants are associated with an underlying accumulation of synaptic vesicles, build-up of the synaptic vesicle priming factor UNC-10/RIM, and decreased synaptic vesicle release from cholinergic motor neurons. Restoration of FSHR-1 to the intestine is sufficient to restore neuromuscular activity and synaptic vesicle localization to fshr-1- deficient animals. Intestine-specific knockdown of FSHR-1 reduces neuromuscular function, indicating FSHR-1 is both necessary and sufficient in the intestine for its neuromuscular effects. Re-expression of FSHR-1 in other sites of endogenous expression, including glial cells and neurons, also restored some neuromuscular deficits, indicating potential cross-tissue regulation from these tissues as well. Genetic interaction studies provide evidence that downstream effectors gsa-1 / Gα S , acy-1 /adenylyl cyclase and sphk-1/ sphingosine kinase and glycoprotein hormone subunit orthologs, GPLA-1/GPA2 and GPLB-1/GPB5, are important for FSHR-1 modulation of the NMJ. Together, our results demonstrate that FSHR-1 modulation directs inter-tissue signaling systems, which promote synaptic vesicle release at neuromuscular synapses.
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Veuthey T, Giunti S, De Rosa MJ, Alkema M, Rayes D. The neurohormone tyramine stimulates the secretion of an Insulin-Like Peptide from the intestine to modulate the systemic stress response in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.06.579207. [PMID: 38370834 PMCID: PMC10871264 DOI: 10.1101/2024.02.06.579207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The DAF-2/insulin/insulin-like growth factor signaling (IIS) pathway plays an evolutionarily conserved role in regulating reproductive development, lifespan, and stress resistance. In C. elegans , DAF-2/IIS signaling is modulated by an extensive array of insulin-like peptides (ILPs) with diverse spatial and temporal expression patterns. However, the release dynamics and specific functions of these ILPs in adapting to different environmental conditions remain poorly understood. Here, we show that the ILP, INS-3, plays a crucial role in modulating the response to different types of stressors in C. elegans . ins-3 mutants display increased resistance to both heat and oxidative stress; however, under favorable conditions, this advantage is countered by slower reproductive development. ins-3 expression in both neurons and the intestine is downregulated in response to environmental stressors. Conversely, the neurohormone tyramine, which is released during the acute flight response, triggers an upregulation in ins-3 expression. Moreover, we found that tyramine negatively impacts environmental stress resistance by stimulating the release of INS-3 from the intestine. The subsequent release of INS-3 systemically activates the DAF-2 pathway, resulting in the inhibition of cytoprotective mechanisms mediated by DAF-16/FOXO and HSF-1. These studies offer mechanistic insights into the brain-gut communication pathway that weighs adaptive strategies to respond to acute and long-term stress scenarios.
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Mir DA, Cox M, Horrocks J, Ma Z, Rogers A. Roles of progranulin and FRamides in neural versus non-neural tissues on dietary restriction-related longevity and proteostasis in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.06.579250. [PMID: 38370756 PMCID: PMC10871266 DOI: 10.1101/2024.02.06.579250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Dietary restriction (DR) mitigates loss of proteostasis associated with aging that underlies neurodegenerative conditions including Alzheimer's disease and related dementias. Previously, we observed increased translational efficiency of certain FMRFamide-like neuropeptide ( flp ) genes and the neuroprotective growth factor progranulin gene prgn-1 under dietary restriction in C. elegans . Here, we tested the effects of flp-5 , flp-14 , flp-15 and pgrn-1 on lifespan and proteostasis under both standard and dietary restriction conditions. We also tested and distinguished function based on their expression in either neuronal or non-neuronal tissue. Lowering the expression of pgrn-1 and flp genes selectively in neural tissue showed no difference in survival under normal feeding conditions nor under DR in two out of three experiments performed. Reduced expression of flp-14 in non-neuronal tissue showed decreased lifespan that was not specific to DR. With respect to proteostasis, a genetic model of DR from mutation of the eat-2 gene that showed increased thermotolerance compared to fully fed wild type animals demonstrated no change in thermotolerance in response to knockdown of pgrn-1 or flp genes. Finally, we tested effects on motility in a neural-specific model of proteotoxicity and found that neuronal knockdown of pgrn-1 and flp genes improved motility in early life regardless of diet. However, knocking these genes down in non-neuronal tissue had variable results. RNAi targeting flp-14 increased motility by day seven of adulthood regardless of diet. Interestingly, non-neuronal RNAi of pgrn-1 decreased motility under standard feeding conditions while DR increased motility for this gene knockdown by day seven (early mid-life). Results show that pgrn-1 , flp-5 , flp-14 , and flp-15 do not have major roles in diet-related changes in longevity or whole-body proteostasis. However, reduced expression of these genes in neurons increases motility early in life in a neural-specific model of proteotoxicity, whereas knockdown of non-neuronal expression mostly increases motility in mid-life under the same conditions.
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Martinez MAQ, Zhao CZ, Moore FEQ, Yee C, Zhang W, Shen K, Martin BL, Matus DQ. Cell cycle perturbation uncouples mitotic progression and invasive behavior in a post-mitotic cell. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.03.16.533034. [PMID: 38370624 PMCID: PMC10871222 DOI: 10.1101/2023.03.16.533034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The acquisition of the post-mitotic state is crucial for the execution of many terminally differentiated cell behaviors during organismal development. However, the mechanisms that maintain the post-mitotic state in this context remain poorly understood. To gain insight into these mechanisms, we used the genetically and visually accessible model of C. elegans anchor cell (AC) invasion into the vulval epithelium. The AC is a terminally differentiated uterine cell that normally exits the cell cycle and enters a post-mitotic state, initiating contact between the uterus and vulva through a cell invasion event. Here, we set out to identify the set of negative cell cycle regulators that maintain the AC in this post-mitotic, invasive state. Our findings revealed a critical role for CKI-1 (p21CIP1/p27KIP1) in redundantly maintaining the post-mitotic state of the AC, as loss of CKI-1 in combination with other negative cell cycle regulators-including CKI-2 (p21CIP1/p27KIP1), LIN-35 (pRb/p107/p130), FZR-1 (Cdh1/Hct1), and LIN-23 (β-TrCP)-resulted in proliferating ACs. Remarkably, time-lapse imaging revealed that these ACs retain their ability to invade. Upon examination of a node in the gene regulatory network controlling AC invasion, we determined that proliferating, invasive ACs do so by maintaining aspects of pro-invasive gene expression. We therefore report that the requirement for a post-mitotic state for invasive cell behavior can be bypassed following direct cell cycle perturbation.
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Affiliation(s)
- Michael A Q Martinez
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Chris Z Zhao
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Frances E Q Moore
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Callista Yee
- Howard Hughes Medical Institute, Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Wan Zhang
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Kang Shen
- Howard Hughes Medical Institute, Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Benjamin L Martin
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - David Q Matus
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
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Ange JS, Weng Y, Stevenson ME, Kaletsky R, Moore RS, Zhou S, Murphy CT. Adult Single-nucleus Neuronal Transcriptomes of Insulin Signaling Mutants Reveal Regulators of Behavior and Learning. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.07.579364. [PMID: 38370779 PMCID: PMC10871314 DOI: 10.1101/2024.02.07.579364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The insulin/insulin-like signaling (IIS) pathway regulates many of C. elegans' adult functions, including learning and memory 1 . While whole-worm and tissue-specific transcriptomic analyses have identified IIS targets 2,3 , a higher-resolution single-cell approach is required to identify changes that confer neuron-specific improvements in the long-lived insulin receptor mutant, daf-2 . To understand how behaviors that are controlled by a small number of neurons change in daf-2 mutants, we used the deep resolution of single-nucleus RNA sequencing to define each neuron type's transcriptome in adult wild-type and daf-2 mutants. First, we found surprising differences between wild-type L4 larval neurons and young adult neurons in chemoreceptor expression, synaptic genes, and learning and memory genes. These Day 1 adult neuron transcriptomes allowed us to identify adult AWC-specific regulators of chemosensory function and to predict neuron-to-neuron peptide/receptor pairs. We then identified gene expression changes that correlate with daf-2's improved cognitive functions, particularly in the AWC sensory neuron that controls learning and associative memory 4 , and used behavioral assays to test their roles in cognitive function. Combining deep single-neuron transcriptomics, genetic manipulation, and behavioral analyses enabled us to identify genes that may function in a single adult neuron to control behavior, including conserved genes that function in learning and memory. One-Sentence Summary Single-nucleus sequencing of adult wild-type and daf-2 C. elegans neurons reveals functionally relevant transcriptional changes, including regulators of chemosensation, learning, and memory.
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Sepulveda GP, Gushchanskaia ES, Mora-Martin A, Esse R, Nikorich I, Ceballos A, Kwan J, Blum BC, Dholiya P, Emili A, Perissi V, Cardamone MD, Grishok A. DOT1L stimulates MYC/Mondo transcription factor activity by promoting its degradation cycle on chromatin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.06.579191. [PMID: 38370658 PMCID: PMC10871221 DOI: 10.1101/2024.02.06.579191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The proto-oncogene c-MYC is a key representative of the MYC transcription factor network regulating growth and metabolism. MML-1 (Myc- and Mondo-like) is its homolog in C. elegans. The functional and molecular cooperation between c-MYC and H3 lysine 79 methyltransferase DOT1L was demonstrated in several human cancer types, and we have earlier discovered the connection between C. elegans MML-1 and DOT-1.1. Here, we demonstrate the critical role of DOT1L/DOT-1.1 in regulating c-MYC/MML-1 target genes genome-wide by ensuring the removal of "spent" transcription factors from chromatin by the nuclear proteasome. Moreover, we uncover a previously unrecognized proteolytic activity of DOT1L, which may facilitate c-MYC turnover. This new mechanism of c-MYC regulation by DOT1L may lead to the development of new approaches for cancer treatment.
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Affiliation(s)
- Gian P. Sepulveda
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Graduate Program in Genetics and Genomics, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Ekaterina S. Gushchanskaia
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Present address: Tessera Therapeutics, Somerville, MA, 02143, USA
| | - Alexandra Mora-Martin
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Present address: Spanish National Cancer Research Center (CNIO), 28029, Madrid, Spain
| | - Ruben Esse
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Present address: Cell and Gene Therapy Catapult, Guy’s Hospital, Great Maze Pond, London SE1 9RT, UK
| | - Iana Nikorich
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Ainhoa Ceballos
- Department of Biochemistry and Molecular Biophysics, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
- Present address: Research Unit, Diagnostica Longwood S.L. 50011 Zaragoza, Spain
| | - Julian Kwan
- Center for Network Systems Biology, Boston University, Boston, MA, 02118, USA
| | - Benjamin C. Blum
- Center for Network Systems Biology, Boston University, Boston, MA, 02118, USA
| | - Prakruti Dholiya
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Andrew Emili
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Center for Network Systems Biology, Boston University, Boston, MA, 02118, USA
- Division of Computational Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Present address: OHSU Knight Cancer Institute, School of Medicine, Portland, OR, 97239, USA
| | - Valentina Perissi
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Maria D. Cardamone
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Present address: Korro Bio Inc., Cambridge, MA, 02139, USA
| | - Alla Grishok
- Department of Biochemistry & Cell Biology, Boston University School of Medicine, Boston, MA, 02118, USA
- Genome Science Institute, Boston University, Boston, MA, 02118, USA
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Otarigho B, Butts AF, Aballay A. Neuronal NPR-15 modulates molecular and behavioral immune responses via the amphid sensory neuron-intestinal axis in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.27.550570. [PMID: 37546751 PMCID: PMC10402133 DOI: 10.1101/2023.07.27.550570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
The survival of hosts during infections relies on their ability to mount effective molecular and behavioral immune responses. Despite extensive research on these defense strategies in various species, including the model organism Caenorhabditis elegans, the neural mechanisms underlying their interaction remain poorly understood. Previous studies have highlighted the role of neural G protein-coupled receptors (GPCRs) in regulating both immunity and pathogen avoidance, which is particularly dependent on aerotaxis. To address this knowledge gap, we conducted a screen of mutants in neuropeptide receptor family genes. We found that loss-of-function mutations in npr-15 activated immunity while suppressing pathogen avoidance behavior. Through further analysis, NPR-15 was found to regulate immunity by modulating the activity of key transcription factors, namely GATA/ELT-2 and TFEB/HLH-30. Surprisingly, the lack of pathogen avoidance of npr-15 mutant animals was not influenced by oxygen levels. Moreover, our studies revealed that the amphid sensory neuron ASJ is involved in mediating the immune and behavioral responses orchestrated by NPR-15. Additionally, NPR-15 was found to regulate avoidance behavior via the TRPM gene, GON-2, which may sense the intestinal distension caused by bacterial colonization to elicit pathogen avoidance. Our study contributes to a broader understanding of host defense strategies and mechanisms underlining the interaction between molecular and behavioral immune responses.
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Affiliation(s)
- Benson Otarigho
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Anna Frances Butts
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Alejandro Aballay
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth Houston, TX
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Sands B, Yun SR, Oshima J, Mendenhall AR. Maternal histone methyltransferases antagonistically regulate monoallelic expression in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.22.576748. [PMID: 38328214 PMCID: PMC10849558 DOI: 10.1101/2024.01.22.576748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Undefined epigenetic programs act to probabilistically silence individual autosomal alleles, generating unique individuals, even from genetic clones. This sort of random monoallelic expression can explain variation in traits and diseases that differences in genes and environments cannot. Here, we developed the nematode Caenorhabditis elegans to study monoallelic expression in whole tissues, and defined a developmental genetic regulation pathway. We found maternal H3K9 histone methyltransferase (HMT) SET-25/SUV39/G9a works with HPL-2/HP1 and LIN-61/L3MBTL2 to randomly silence alleles in the intestinal progenitor E-cell of 8-cell embryos to cause monoallelic expression. SET-25 was antagonized by another maternal H3K9 HMT, MET-2/SETDB1, which works with LIN-65/ATF7ZIP and ARLE-14/ARL14EP to prevent monoallelic expression. The HMT-catalytic SET domains of both MET-2 and SET-25 were required for regulating monoallelic expression. Our data support a model wherein SET-25 and MET-2 regulate histones during development to generate patterns of somatic monoallelic expression that are persistent but not heritable.
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Kudron M, Gevirtzman L, Victorsen A, Lear BC, Gao J, Xu J, Samanta S, Frink E, Tran-Pearson A, Huynh C, Vafeados D, Hammonds A, Fisher W, Wall M, Wesseling G, Hernandez V, Lin Z, Kasparian M, White K, Allada R, Gerstein M, Hillier L, Celniker SE, Reinke V, Waterston RH. Binding profiles for 954 Drosophila and C. elegans transcription factors reveal tissue specific regulatory relationships. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.18.576242. [PMID: 38293065 PMCID: PMC10827215 DOI: 10.1101/2024.01.18.576242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
A catalog of transcription factor (TF) binding sites in the genome is critical for deciphering regulatory relationships. Here we present the culmination of the modERN (model organism Encyclopedia of Regulatory Networks) consortium that systematically assayed TF binding events in vivo in two major model organisms, Drosophila melanogaster (fly) and Caenorhabditis elegans (worm). We describe key features of these datasets, comprising 604 TFs identifying 3.6M sites in the fly and 350 TFs identifying 0.9 M sites in the worm. Applying a machine learning model to these data identifies sets of TFs with a prominent role in promoting target gene expression in specific cell types. TF binding data are available through the ENCODE Data Coordinating Center and at https://epic.gs.washington.edu/modERNresource, which provides access to processed and summary data, as well as widgets to probe cell type-specific TF-target relationships. These data are a rich resource that should fuel investigations into TF function during development.
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Affiliation(s)
- Michelle Kudron
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Louis Gevirtzman
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Alec Victorsen
- Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN 55455
| | - Bridget C. Lear
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Jiahao Gao
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
| | - Jinrui Xu
- Department of Biology, Howard University, Washington, District of Columbia 20059, USA
- Center for Applied Data Science and Analytics, Howard University, Washington, District of Columbia 20059, USA
| | - Swapna Samanta
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Emily Frink
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Adri Tran-Pearson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Chau Huynh
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Dionne Vafeados
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Ann Hammonds
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - William Fisher
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Martha Wall
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Greg Wesseling
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Vanessa Hernandez
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Zhichun Lin
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Mary Kasparian
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Kevin White
- Department of Biochemistry and Precision Medicine Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
| | - Ravi Allada
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Mark Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
- Department of Statistics and Data Science, Yale University, New Haven, Connecticut 06520, USA
| | - LaDeana Hillier
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Susan E. Celniker
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Valerie Reinke
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Robert H. Waterston
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
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Wu J, Yang OJ, Soderblom EJ, Yan D. Heat Shock Proteins Function as Signaling Molecules to Mediate Neuron-Glia Communication During Aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.18.576052. [PMID: 38293019 PMCID: PMC10827141 DOI: 10.1101/2024.01.18.576052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
The nervous system is primarily composed of neurons and glia, and the communication between them plays profound roles in regulating the development and function of the brain. Neuron-glia signal transduction is known to be mediated by secreted or juxtacrine signals through ligand-receptor interactions on the cell membrane. Here, we report a novel mechanism for neuron-glia signal transduction, wherein neurons transmit proteins to glia through extracellular vesicles, activating glial signaling pathways. We find that in the amphid sensory organ of Caenorhabditis elegans, different sensory neurons exhibit varying aging rates. This discrepancy in aging is governed by the crosstalk between neurons and glia. We demonstrate that early-aged neurons can transmit heat shock proteins (HSP) to glia via extracellular vesicles. These neuronal HSPs activate the IRE1-XBP1 pathway, further increasing their expression in glia, forming a positive feedback loop. Ultimately, the activation of the IRE1-XBP-1 pathway leads to the transcriptional regulation of chondroitin synthases to protect glia-embedded neurons from aging-associated functional decline. Therefore, our studies unveil a novel mechanism for neuron-glia communication in the nervous system and provide new insights into our understanding of brain aging.
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Affiliation(s)
- Jieyu Wu
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Olivia Jiaming Yang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
- East Chapel Hill High School, Chapel Hill, NC 27514, USA
| | - Erik J. Soderblom
- Proteomics and Metabolomics Core Facility, Duke University Medical School, Durham, NC 27710, USA
| | - Dong Yan
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell biology, Department of Neurobiology, Regeneration next, and Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC 27710, USA
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Ji H, Chen D, Fang-Yen C. Segmentation-free measurement of locomotor frequency in Caenorhabditis elegans using image invariants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.16.575892. [PMID: 38293059 PMCID: PMC10827210 DOI: 10.1101/2024.01.16.575892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
An animal's locomotor rate is an important indicator of its motility. In studies of the nematode C. elegans , assays of the frequency of body bending waves have often been used to discern the effects of mutations, drugs, or aging. Traditional manual methods for measuring locomotor frequency are low in throughput and subject to human error. Most current automated methods depend on image segmentation, which requires high image quality and is prone to errors. Here, we describe an algorithm for automated estimation of C. elegans locomotor frequency using image invariants, i.e., shape-based parameters that are independent of object translation, rotation, and scaling. For each video frame, the method calculates a combination of 8 Hu's moment invariants and a set of Maximally Stable Extremal Regions (MSER) invariants. The algorithm then calculates the locomotor frequency by computing the autocorrelation of the time sequence of the invariant ensemble. Results of our method show excellent agreement with manual or segmentation-based results over a wide range of frequencies. We show that compared to the segmentation method that analyzes a worm's shape, our method is more robust to low image quality. We demonstrate the system's capabilities by testing the effects of serotonin and serotonin pathway mutants on locomotor frequency.
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46
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Pal A, Vasudevan V, Houle F, Lantin M, Maniates KA, Quevillon Huberdeau M, Abbott A, Simard MJ. Defining the contribution of microRNA-specific slicing Argonautes in animals. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.19.524781. [PMID: 36711744 PMCID: PMC9882343 DOI: 10.1101/2023.01.19.524781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
microRNAs regulate gene expression through interaction with an Argonaute protein family member. While some members of this protein family retain an enzymatic activity capable of cleaving RNA molecules complementary to Argonaute-bound small RNAs, the role of the slicing activity in the canonical microRNA pathway is still unclear in animals. To address the importance of slicing Argonautes in animals, we created Caenorhabditis elegans strains, carrying catalytically dead endogenous ALG-1 and ALG-2, the only two slicing Argonautes essential for the miRNA pathway in this animal model. We observe that the loss of ALG-1 and ALG-2 slicing activity affects overall animal fitness and causes phenotypes, reminiscent of miRNA defects, only when grown and maintained at restrictive temperature. Furthermore, the analysis of global miRNA expression shows that the catalytic activity of ALG-1 and ALG-2 differentially regulate the level of specific subsets of miRNAs in young adults. We also demonstrate that altering the slicing activity of those miRNA-specific Argonautes does not result in any defect in the production of canonical miRNAs. Together, these data support that the slicing activity of miRNA-specific Argonautes function to maintain the levels of a set of miRNAs for optimal viability and fitness in animals particularly exposed to specific growing conditions.
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Ray AK, Priya A, Malik MZ, Thanaraj TA, Singh AK, Mago P, Ghosh C, Shalimar, Tandon R, Chaturvedi R. Conserved Cardiovascular Network: Bioinformatics Insights into Genes and Pathways for Establishing Caenorhabditis elegans as an Animal Model for Cardiovascular Diseases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.24.573256. [PMID: 38234826 PMCID: PMC10793405 DOI: 10.1101/2023.12.24.573256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Cardiovascular disease (CVD) is a collective term for disorders of the heart and blood vessels. The molecular events and biochemical pathways associated with CVD are difficult to study in clinical settings on patients and in vitro conditions. Animal models play a pivotal and indispensable role in cardiovascular disease (CVD) research. Caenorhabditis elegans , a nematode species, has emerged as a prominent experimental organism widely utilised in various biomedical research fields. However, the specific number of CVD-related genes and pathways within the C. elegans genome remains undisclosed to date, limiting its in-depth utilisation for investigations. In the present study, we conducted a comprehensive analysis of genes and pathways related to CVD within the genomes of humans and C. elegans through a systematic bioinformatic approach. A total of 1113 genes in C. elegans orthologous to the most significant CVD-related genes in humans were identified, and the GO terms and pathways were compared to study the pathways that are conserved between the two species. In order to infer the functions of CVD-related orthologous genes in C. elegans, a PPI network was constructed. Orthologous gene PPI network analysis results reveal the hubs and important KRs: pmk-1, daf-21, gpb-1, crh-1, enpl-1, eef-1G, acdh-8, hif-1, pmk-2, and aha-1 in C. elegans. Modules were identified for determining the role of the orthologous genes at various levels in the created network. We also identified 9 commonly enriched pathways between humans and C. elegans linked with CVDs that include autophagy (animal), the ErbB signalling pathway, the FoxO signalling pathway, the MAPK signalling pathway, ABC transporters, the biosynthesis of unsaturated fatty acids, fatty acid metabolism, glutathione metabolism, and metabolic pathways. This study provides the first systematic genomic approach to explore the CVD-associated genes and pathways that are present in C. elegans, supporting the use of C. elegans as a prominent animal model organism for cardiovascular diseases.
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Goda M, Shribak M, Ikeda Z, Okada N, Tani T, Goshima G, Oldenbourg R, Kimura A. Live-cell imaging under centrifugation characterized the cellular force for nuclear centration in the Caenorhabditis elegans embryo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.03.574024. [PMID: 38260704 PMCID: PMC10802357 DOI: 10.1101/2024.01.03.574024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Organelles in cells are appropriately positioned, despite crowding in the cytoplasm. However, our understanding of the force required to move large organelles, such as the nucleus, inside the cytoplasm is limited, in part owing to a lack of accurate methods for measurement. We devised a novel method to apply forces to the nucleus of living, wild-type Caenorhabditis elegans embryos to measure the force generated inside the cell. We utilized a centrifuge polarizing microscope (CPM) to apply centrifugal force and orientation-independent differential interference contrast (OI-DIC) microscopy to characterize the mass density of the nucleus and cytoplasm. The cellular forces moving the nucleus toward the cell center increased linearly at ~14 pN/μm depending on the distance from the center. The frictional coefficient was ~1,100 pN s/μm. The measured values were smaller than previously reported estimates for sea urchin embryos. The forces were consistent with the centrosome-organelle mutual pulling model for nuclear centration. Frictional coefficient was reduced when microtubules were shorter or detached from nuclei in mutant embryos, demonstrating the contribution of astral microtubules. Finally, the frictional coefficient was higher than a theoretical estimate, indicating the contribution of uncharacterized properties of the cytoplasm.
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Affiliation(s)
- Makoto Goda
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
- Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
- Nagoya University, Nagoya 464-8602, Japan
| | - Michael Shribak
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
| | - Zenki Ikeda
- National Institute of Genetics, Mishima 411-8540, Japan
- Sokendai (Graduate University for Advanced Studies) Mishima, Mishima 411-8540, Japan
| | | | - Tomomi Tani
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Ikeda 563-8577, Japan
| | - Gohta Goshima
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
- Nagoya University, Nagoya 464-8602, Japan
| | | | - Akatsuki Kimura
- Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
- National Institute of Genetics, Mishima 411-8540, Japan
- Sokendai (Graduate University for Advanced Studies) Mishima, Mishima 411-8540, Japan
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Taylor SKB, Hartman JH, Gupta BP. Neurotrophic factor MANF regulates autophagy and lysosome function to promote proteostasis in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.31.551399. [PMID: 38260421 PMCID: PMC10802257 DOI: 10.1101/2023.07.31.551399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The conserved mesencephalic astrocyte-derived neurotrophic factor (MANF) protects dopaminergic neurons but also functions in several other tissues. Previously, we showed that Caenorhabditis elegans manf-1 null mutants have increased ER stress, dopaminergic neurodegeneration, protein aggregation, slower growth, and a reduced lifespan. The multiple requirements of MANF in different systems suggest its essential role in regulating cellular processes. However, how intracellular and extracellular MANF regulates broader cellular function remains unknown. Here, we report a novel mechanism of action for manf-1 that involves the autophagy transcription factor HLH-30/TFEB-mediated signaling to regulate lysosomal function and aging. We generated multiple transgenic strains overexpressing MANF-1 and found that animals had extended lifespan, reduced protein aggregation, and improved neuronal health. Using a fluorescently tagged MANF-1, we observed different tissue localization of MANF-1 depending on the ER retention signal. Further subcellular analysis showed that MANF-1 localizes within cells to the lysosomes. These findings were consistent with our transcriptomic studies and, together with analysis of autophagy regulators, demonstrate that MANF-1 regulates protein homeostasis through increased autophagy and lysosomal activity. Collectively, our findings establish MANF as a critical regulator of the stress response, proteostasis, and aging.
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Affiliation(s)
- Shane K. B. Taylor
- Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Jessica H. Hartman
- Department of Biochemistry & Molecular Biology and Department of Regenerative Medicine & Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Bhagwati P. Gupta
- Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada
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50
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Fujii K, Kondo T, Kimura A. Enucleation of the C. elegans embryo revealed dynein-dependent spacing between microtubule asters. Life Sci Alliance 2024; 7:e202302427. [PMID: 37931957 PMCID: PMC10627822 DOI: 10.26508/lsa.202302427] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/08/2023] Open
Abstract
The intracellular positioning of the centrosome, a major microtubule-organizing center, is important for cellular functions. One of the features of centrosome positioning is the spacing between centrosomes; however, the underlying mechanisms are not fully understood. To characterize the spacing activity in Caenorhabditis elegans embryos, a genetic setup was developed to produce enucleated embryos. The centrosome was duplicated multiple times in the enucleated embryo, which enabled us to characterize the chromosome-independent spacing activity between sister and non-sister centrosome pairs. We found that the timely spacing depended on cytoplasmic dynein, and we propose a stoichiometric model of cortical and cytoplasmic pulling forces for the spacing between centrosomes. We also observed dynein-independent but non-muscle myosin II-dependent movement of centrosomes in the later cell cycle phase. The spacing mechanisms revealed in this study are expected to function between centrosomes in general, regardless of the presence of a chromosome/nucleus between them, including centrosome separation and spindle elongation.
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Affiliation(s)
- Ken Fujii
- https://ror.org/0516ah480 Department of Genetics, School of Life Science, Sokendai (Graduate University for Advanced Studies) Mishima, Japan
- https://ror.org/02xg1m795 Cell Architecture Laboratory, National Institute of Genetics, Mishima, Japan
| | - Tomo Kondo
- https://ror.org/02xg1m795 Cell Architecture Laboratory, National Institute of Genetics, Mishima, Japan
| | - Akatsuki Kimura
- https://ror.org/0516ah480 Department of Genetics, School of Life Science, Sokendai (Graduate University for Advanced Studies) Mishima, Japan
- https://ror.org/02xg1m795 Cell Architecture Laboratory, National Institute of Genetics, Mishima, Japan
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