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Chantab K, Rao Z, Zheng X, Han R, Cao L. Ascarosides and Symbiotic Bacteria of Entomopathogenic Nematodes Regulate Host Immune Response in Galleria mellonella Larvae. INSECTS 2024; 15:514. [PMID: 39057246 PMCID: PMC11277396 DOI: 10.3390/insects15070514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/20/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024]
Abstract
Insects protect themselves through their immune systems. Entomopathogenic nematodes and their bacterial symbionts are widely used for the biocontrol of economically important pests. Ascarosides are pheromones that regulate nematode behaviors, such as aggregation, avoidance, mating, dispersal, and dauer recovery and formation. However, whether ascarosides influence the immune response of insects remains unexplored. In this study, we co-injected ascarosides and symbiotic Photorhabdus luminescens subsp. kayaii H06 bacteria derived from Heterorhabditis bacteriophora H06 into the last instar larvae of Galleria mellonella. We recorded larval mortality and analyzed the expressions of AMPs, ROS/RNS, and LPSs. Our results revealed a process in which ascarosides, acting as enhancers of the symbiotic bacteria, co-induced G. mellonella immunity by significantly increasing oxidative stress responses and secreting AMPs (gallerimycin, gloverin, and cecropin). This led to a reduction in color intensity and the symbiotic bacteria load, ultimately resulting in delayed host mortality compared to either ascarosides or symbiotic bacteria. These findings demonstrate the cross-kingdom regulation of insects and symbiotic bacteria by nematode pheromones. Furthermore, our results suggest that G. mellonella larvae may employ nematode pheromones secreted by IJs to modulate insect immunity during early infection, particularly in the presence of symbiotic bacteria, for enhancing resistance to invasive bacteria in the hemolymph.
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Affiliation(s)
- Kanjana Chantab
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
- Department of Plant Sciences, Faculty of Agriculture and Technology, Rajamangala University of Technology Isan, Surin 32000, Thailand
| | - Zhongchen Rao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - Xuehong Zheng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - Richou Han
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - Li Cao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
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2
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Guden RM, Haegeman A, Ruttink T, Moens T, Derycke S. Nematodes alter the taxonomic and functional profiles of benthic bacterial communities: A metatranscriptomic approach. Mol Ecol 2024; 33:e17331. [PMID: 38533629 DOI: 10.1111/mec.17331] [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: 06/21/2023] [Revised: 02/25/2024] [Accepted: 03/18/2024] [Indexed: 03/28/2024]
Abstract
Marine sediments cover 70% of the Earth's surface, and harbour diverse bacterial communities critical for marine biogeochemical processes, which affect climate change, biodiversity and ecosystem functioning. Nematodes, the most abundant and species-rich metazoan organisms in marine sediments, in turn, affect benthic bacterial communities and bacterial-mediated ecological processes, but the underlying mechanisms by which they affect biogeochemical cycles remain poorly understood. Here, we demonstrate using a metatranscriptomic approach that nematodes alter the taxonomic and functional profiles of benthic bacterial communities. We found particularly strong stimulation of nitrogen-fixing and methane-oxidizing bacteria in the presence of nematodes, as well as increased functional activity associated with methane metabolism and degradation of various carbon compounds. This study provides empirical evidence that the presence of nematodes results in taxonomic and functional shifts in active bacterial communities, indicating that nematodes may play an important role in benthic ecosystem processes.
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Affiliation(s)
- Rodgee Mae Guden
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
| | - Annelies Haegeman
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Melle, Belgium
| | - Tom Ruttink
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Melle, Belgium
| | - Tom Moens
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
| | - Sofie Derycke
- Marine Biology Unit, Department of Biology, Ghent University, Ghent, Belgium
- Aquatic Environment and Quality, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Oostende, Belgium
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3
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Wrobel CJJ, Schroeder FC. Repurposing degradation pathways for modular metabolite biosynthesis in nematodes. Nat Chem Biol 2023; 19:676-686. [PMID: 37024728 PMCID: PMC10559835 DOI: 10.1038/s41589-023-01301-w] [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: 07/05/2022] [Accepted: 02/24/2023] [Indexed: 04/08/2023]
Abstract
Recent studies have revealed that Caenorhabditis elegans and other nematodes repurpose products from biochemical degradation pathways for the combinatorial assembly of complex modular structures that serve diverse signaling functions. Building blocks from neurotransmitter, amino acid, nucleoside and fatty acid metabolism are attached to scaffolds based on the dideoxyhexose ascarylose or glucose, resulting in hundreds of modular ascarosides and glucosides. Genome-wide association studies have identified carboxylesterases as the key enzymes mediating modular assembly, enabling rapid compound discovery via untargeted metabolomics and suggesting that modular metabolite biosynthesis originates from the 'hijacking' of conserved detoxification mechanisms. Modular metabolites thus represent a distinct biosynthetic strategy for generating structural and functional diversity in nematodes, complementing the primarily polyketide synthase- and nonribosomal peptide synthetase-derived universe of microbial natural products. Although many aspects of modular metabolite biosynthesis and function remain to be elucidated, their identification demonstrates how phenotype-driven compound discovery, untargeted metabolomics and genomic approaches can synergize to facilitate the annotation of metabolic dark matter.
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Affiliation(s)
- Chester J J Wrobel
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
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4
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Yang B, Wang J, Zheng X, Wang X. Nematode Pheromones: Structures and Functions. Molecules 2023; 28:molecules28052409. [PMID: 36903652 PMCID: PMC10005090 DOI: 10.3390/molecules28052409] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 03/01/2023] [Accepted: 03/04/2023] [Indexed: 03/09/2023] Open
Abstract
Pheromones are chemical signals secreted by one individual that can affect the behaviors of other individuals within the same species. Ascaroside is an evolutionarily conserved family of nematode pheromones that play an integral role in the development, lifespan, propagation, and stress response of nematodes. Their general structure comprises the dideoxysugar ascarylose and fatty-acid-like side chains. Ascarosides can vary structurally and functionally according to the lengths of their side chains and how they are derivatized with different moieties. In this review, we mainly describe the chemical structures of ascarosides and their different effects on the development, mating, and aggregation of nematodes, as well as how they are synthesized and regulated. In addition, we discuss their influences on other species in various aspects. This review provides a reference for the functions and structures of ascarosides and enables their better application.
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Rutter WB, Franco J, Gleason C. Rooting Out the Mechanisms of Root-Knot Nematode-Plant Interactions. ANNUAL REVIEW OF PHYTOPATHOLOGY 2022; 60:43-76. [PMID: 35316614 DOI: 10.1146/annurev-phyto-021621-120943] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Root-knot nematodes (RKNs; Meloidogyne spp.) engage in complex parasitic interactions with many different host plants around the world, initiating elaborate feeding sites and disrupting host root architecture. Although RKNs have been the focus of research for many decades, new molecular tools have provided useful insights into the biological mechanisms these pests use to infect and manipulate their hosts. From identifying host defense mechanisms underlying resistance to RKNs to characterizing nematode effectors that alter host cellular functions, the past decade of research has significantly expanded our understanding of RKN-plant interactions, and the increasing number of quality parasite and host genomes promises to enhance future research efforts into RKNs. In this review, we have highlighted recent discoveries, summarized the current understanding within the field, and provided links to new and useful resources for researchers. Our goal is to offer insights and tools to support the study of molecular RKN-plant interactions.
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Affiliation(s)
- William B Rutter
- US Vegetable Laboratory, USDA Agricultural Research Service, Charleston, South Carolina, USA
| | - Jessica Franco
- Department of Plant Pathology, Washington State University, Pullman, Washington, USA;
| | - Cynthia Gleason
- Department of Plant Pathology, Washington State University, Pullman, Washington, USA;
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6
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Varão Moura A, Aparecido Rosini Silva A, Domingos Santo da Silva J, Aleixo Leal Pedroza L, Bornhorst J, Stiboller M, Schwerdtle T, Gubert P. Determination of ions in Caenorhabditis elegans by ion chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2022; 1204:123312. [DOI: 10.1016/j.jchromb.2022.123312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 05/04/2022] [Accepted: 05/25/2022] [Indexed: 11/27/2022]
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Nematode ascarosides attenuate mammalian type 2 inflammatory responses. Proc Natl Acad Sci U S A 2022; 119:2108686119. [PMID: 35210367 PMCID: PMC8892368 DOI: 10.1073/pnas.2108686119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/28/2021] [Indexed: 01/08/2023] Open
Abstract
Animal proof-of-concept studies have shown that roundworms have a protective effect against immune-dysregulated disorders, but it has been difficult to study in human trials without individual nematode-derived molecules to develop and test. We discovered that ascarosides, molecules that are secreted by diverse nematodes, suppress asthma in a rodent model via modulation of expression of Il33, a key epithelial cytokine for induction of type 2 immunity, in addition to decreasing memory-type pathogenic Th2 cells and ILC2s and increasing the Il10-expressing subpopulation of interstitial macrophages in the lung. Thus, ascarosides suppress type 2 immune response by affecting both innate and adaptive immunity and could define a potent class of small molecule drugs to treat allergic airway diseases. Mounting evidence suggests that nematode infection can protect against disorders of immune dysregulation. Administration of live parasites or their excretory/secretory (ES) products has shown therapeutic effects across a wide range of animal models for immune disorders, including asthma. Human clinical trials of live parasite ingestion for the treatment of immune disorders have produced promising results, yet concerns persist regarding the ingestion of pathogenic organisms and the immunogenicity of protein components. Despite extensive efforts to define the active components of ES products, no small molecules with immune regulatory activity have been identified from nematodes. Here we show that an evolutionarily conserved family of nematode pheromones called ascarosides strongly modulates the pulmonary immune response and reduces asthma severity in mice. Screening the inhibitory effects of ascarosides produced by animal-parasitic nematodes on the development of asthma in an ovalbumin (OVA) murine model, we found that administration of nanogram quantities of ascr#7 prevented the development of lung eosinophilia, goblet cell metaplasia, and airway hyperreactivity. Ascr#7 suppressed the production of IL-33 from lung epithelial cells and reduced the number of memory-type pathogenic Th2 cells and ILC2s in the lung, both key drivers of the pathology of asthma. Our findings suggest that the mammalian immune system recognizes ascarosides as an evolutionarily conserved molecular signature of parasitic nematodes. The identification of a nematode-produced small molecule underlying the well-documented immunomodulatory effects of ES products may enable the development of treatment strategies for allergic diseases.
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8
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Metabolic Analysis of the Development of the Plant-Parasitic Cyst Nematodes Heterodera schachtii and Heterodera trifolii by Capillary Electrophoresis Time-of-Flight Mass Spectrometry. Int J Mol Sci 2021; 22:ijms221910488. [PMID: 34638828 PMCID: PMC8508704 DOI: 10.3390/ijms221910488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 09/26/2021] [Accepted: 09/27/2021] [Indexed: 12/31/2022] Open
Abstract
The cyst nematodes Heterodera schachtii and Heterodera trifolii, whose major hosts are sugar beet and clover, respectively, damage a broad range of plants, resulting in significant economic losses. Nematodes synthesize metabolites for organismal development and social communication. We performed metabolic profiling of H. schachtii and H. trifolii in the egg, juvenile 2 (J2), and female stages. In all, 392 peaks were analyzed by capillary electrophoresis time-of-flight mass spectrometry, which revealed a lot of similarities among metabolomes. Aromatic amino acid metabolism, carbohydrate metabolism, choline metabolism, methionine salvage pathway, glutamate metabolism, urea cycle, glycolysis, gluconeogenesis, coenzyme metabolism, purine metabolism, pyrimidine metabolism, and tricarboxylic acid (TCA) cycle for energy conversion (β-oxidation and branched-chain amino acid metabolism) energy storage were involved in all stages studied. The egg and female stages synthesized higher levels of metabolites compared to the J2 stage. The key metabolites detected were glycerol, guanosine, hydroxyproline, citric acid, phosphorylcholine, and the essential amino acids Phe, Leu, Ser, and Val. Metabolites, such as hydroxyproline, acetylcholine, serotonin, glutathione, and glutathione disulfide, which are associated with growth and reproduction, mobility, and neurotransmission, predominated in the J2 stage. Other metabolites, such as SAM, 3PSer, 3-ureidopropionic acid, CTP, UDP, UTP, 3-hydroxy-3-methylglutaric acid, 2-amino-2-(hydroxymethyl-1,3-propanediol, 2-hydroxy-4-methylvaleric acid, Gly Asp, glucuronic acid-3 + galacturonic acid-3 Ser-Glu, citrulline, and γ-Glu-Asn, were highly detected in the egg stage. Meanwhile, nicotinamide, 3-PG, F6P, Cys, ADP-Ribose, Ru5P, S7P, IMP, DAP, diethanolamine, p-Hydroxybenzoic acid, and γ-Glu-Arg_divalent were unique to the J2 stage. Formiminoglutamic acid, nicotinaminde riboside + XC0089, putrescine, thiamine 2,3-dihydroxybenzoic acid, 3-methyladenine, caffeic acid, ferulic acid, m-hydrobenzoic acid, o- and p-coumaric acid, and shikimic acid were specific to the female stage. Overall, highly similar identities and quantities of metabolites between the corresponding stages of the two species of nematode were observed. Our results will be a valuable resource for further studies of physiological changes related to the development of nematodes and nematode-plant interactions.
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9
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Wrobel CJJ, Yu J, Rodrigues PR, Ludewig AH, Curtis BJ, Cohen SM, Fox BW, O'Donnell MP, Sternberg PW, Schroeder FC. Combinatorial Assembly of Modular Glucosides via Carboxylesterases Regulates C. elegans Starvation Survival. J Am Chem Soc 2021; 143:14676-14683. [PMID: 34460264 DOI: 10.1021/jacs.1c05908] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The recently discovered modular glucosides (MOGLs) form a large metabolite library derived from combinatorial assembly of moieties from amino acid, neurotransmitter, and lipid metabolism in the model organism C. elegans. Combining CRISPR-Cas9 genome editing, comparative metabolomics, and synthesis, we show that the carboxylesterase homologue Cel-CEST-1.2 is responsible for specific 2-O-acylation of diverse glucose scaffolds with a wide variety of building blocks, resulting in more than 150 different MOGLs. We further show that this biosynthetic role is conserved for the closest homologue of Cel-CEST-1.2 in the related nematode species C. briggsae, Cbr-CEST-2. Expression of Cel-cest-1.2 and MOGL biosynthesis are strongly induced by starvation conditions in C. elegans, one of the premier model systems for mechanisms connecting nutrition and physiology. Cel-cest-1.2-deletion results in early death of adult animals under starvation conditions, providing first insights into the biological functions of MOGLs.
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Affiliation(s)
- Chester J J Wrobel
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jingfang Yu
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Pedro R Rodrigues
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Andreas H Ludewig
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brian J Curtis
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Sarah M Cohen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Bennett W Fox
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Michael P O'Donnell
- Department of Molecular, Cellular and Developmental Biology, New Haven, Connecticut 06511, United States
| | - Paul W Sternberg
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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10
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Dong C, Dolke F, Bandi S, Paetz C, von Reuß SH. Dimerization of conserved ascaroside building blocks generates species-specific male attractants in Caenorhabditis nematodes. Org Biomol Chem 2021; 18:5253-5263. [PMID: 32614033 DOI: 10.1039/d0ob00799d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Comparative ascaroside profiling of Caenorhabditis nematodes using HPLC-ESI-(-)-MS/MS precursor ion scanning revealed a class of highly species-specific ascaroside dimers. Their 2- and 4-isomeric, homo- and heterodimeric structures were identified using a combination of HPLC-ESI-(+)-HR-MS/MS spectrometry and high-resolution dqf-COSY NMR spectroscopy. Structure assignments were confirmed by total synthesis of representative examples. Functional characterization using holding assays indicated that males of Caenorhabditis remanei and Caenorhabditis nigoni are exclusively retained by their conspecific ascaroside dimers, demonstrating that dimerization of conserved monomeric building blocks represents a yet undescribed mechanism that generates species-specific signaling molecules in the Caenorhabditis genus.
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Affiliation(s)
- Chuanfu Dong
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Franziska Dolke
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Siva Bandi
- Laboratory for Bioanalytical Chemistry, Institute of Chemistry, University of Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland.
| | - Christian Paetz
- Research Group Biosynthesis/NMR, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Stephan H von Reuß
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany and Laboratory for Bioanalytical Chemistry, Institute of Chemistry, University of Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland.
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11
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Carstensen HR, Villalon RM, Banerjee N, Hallem EA, Hong RL. Steroid hormone pathways coordinate developmental diapause and olfactory remodeling in Pristionchus pacificus. Genetics 2021; 218:6272519. [PMID: 33963848 DOI: 10.1093/genetics/iyab071] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 04/26/2021] [Indexed: 12/31/2022] Open
Abstract
Developmental and behavioral plasticity allow animals to prioritize alternative genetic programs during fluctuating environments. Behavioral remodeling may be acute in animals that interact with host organisms, since reproductive adults and the developmentally arrested larvae often have different ethological needs for chemical stimuli. To understand the genes that coordinate the development and host-seeking behavior, we used the entomophilic nematode Pristionchus pacificus to characterize dauer-constitutive mutants (Daf-c) that inappropriately enter developmental diapause to become dauer larvae. We found two Daf-c loci with dauer-constitutive and cuticle exsheathment phenotypes that can be rescued by the feeding of Δ7-dafachronic acid, and that are dependent on the conserved canonical steroid hormone receptor Ppa-DAF-12. Specifically at one locus, deletions in the sole hydroxysteroid dehydrogenase (HSD) in P. pacificus resulted in Daf-c phenotypes. Ppa-hsd-2 is expressed in the canal-associated neurons (CANs) and excretory cells whose homologous cells in Caenorhabditis elegans are not known to be involved in the dauer decision. While in wildtype only dauer larvae are attracted to host odors, hsd-2 mutant adults show enhanced attraction to the host beetle pheromone, along with ectopic activation of a marker for putative olfactory neurons, Ppa-odr-3. Surprisingly, this enhanced odor attraction acts independently of the Δ7-DA/DAF-12 module, suggesting that Ppa-HSD-2 may be responsible for several steroid hormone products involved in coordinating the dauer decision and host-seeking behavior in P. pacificus.
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Affiliation(s)
- Heather R Carstensen
- Department of Biology, California State University, Northridge, Northridge, CA 91330-8303, USA
| | - Reinard M Villalon
- Department of Biology, California State University, Northridge, Northridge, CA 91330-8303, USA
| | - Navonil Banerjee
- Department of Microbiology, Immunology & Molecular Genetics and Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Elissa A Hallem
- Department of Microbiology, Immunology & Molecular Genetics and Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ray L Hong
- Department of Biology, California State University, Northridge, Northridge, CA 91330-8303, USA
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12
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Yu Y, Le HH, Curtis BJ, Wrobel CJJ, Zhang B, Maxwell DN, Pan JY, Schroeder FC. An Untargeted Approach for Revealing Electrophilic Metabolites. ACS Chem Biol 2020; 15:3030-3037. [PMID: 33074644 DOI: 10.1021/acschembio.0c00706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reactive electrophilic intermediates such as coenzyme A esters play central roles in metabolism but are difficult to detect with conventional strategies. Here, we introduce hydroxylamine-based stable isotope labeling to convert reactive electrophilic intermediates into stable derivatives that are easily detectable via LC-MS. In the model system Caenorhabditis elegans, parallel treatment with 14NH2OH and 15NH2OH revealed >1000 labeled metabolites, e.g., derived from peptide, fatty acid, and ascaroside pheromone biosyntheses. Results from NH2OH treatment of a pheromone biosynthesis mutant, acox-1.1, suggested upregulation of thioesterase activity, which was confirmed by gene expression analysis. The upregulated thioesterase contributes to the biosynthesis of a specific subset of ascarosides, determining the balance of dispersal and attractive signals. These results demonstrate the utility of NH2OH labeling for investigating complex biosynthetic networks. Initial results with Aspergillus and human cell lines indicate applicability toward uncovering reactive metabolomes in diverse living systems.
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Affiliation(s)
- Yan Yu
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Henry H. Le
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brian J. Curtis
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Chester J. J. Wrobel
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Bingsen Zhang
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Danielle N. Maxwell
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Judy Y. Pan
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Frank C. Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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13
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Abstract
For the first 25 years after the landmark 1974 paper that launched the field, most C. elegans biologists were content to think of their subjects as solitary creatures. C. elegans presented no shortage of fascinating biological problems, but some of the features that led Brenner to settle on this species-in particular, its free-living, self-fertilizing lifestyle-also seemed to reduce its potential for interesting social behavior. That perspective soon changed, with the last two decades bringing remarkable progress in identifying and understanding the complex interactions between worms. The growing appreciation that C. elegans behavior can only be meaningfully understood in the context of its ecology and evolution ensures that the coming years will see similarly exciting progress.
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Affiliation(s)
- Douglas S Portman
- Departments of Biomedical Genetics, Neuroscience, and Biology, Del Monte Institute for Neuroscience, University of Rochester, Rochester, NY, USA
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14
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Le HH, Wrobel CJ, Cohen SM, Yu J, Park H, Helf MJ, Curtis BJ, Kruempel JC, Rodrigues PR, Hu PJ, Sternberg PW, Schroeder FC. Modular metabolite assembly in Caenorhabditis elegans depends on carboxylesterases and formation of lysosome-related organelles. eLife 2020; 9:61886. [PMID: 33063667 PMCID: PMC7641594 DOI: 10.7554/elife.61886] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 10/14/2020] [Indexed: 02/06/2023] Open
Abstract
Signaling molecules derived from attachment of diverse metabolic building blocks to ascarosides play a central role in the life history of C. elegans and other nematodes; however, many aspects of their biogenesis remain unclear. Using comparative metabolomics, we show that a pathway mediating formation of intestinal lysosome-related organelles (LROs) is required for biosynthesis of most modular ascarosides as well as previously undescribed modular glucosides. Similar to modular ascarosides, the modular glucosides are derived from highly selective assembly of moieties from nucleoside, amino acid, neurotransmitter, and lipid metabolism, suggesting that modular glucosides, like the ascarosides, may serve signaling functions. We further show that carboxylesterases that localize to intestinal organelles are required for the assembly of both modular ascarosides and glucosides via ester and amide linkages. Further exploration of LRO function and carboxylesterase homologs in C. elegans and other animals may reveal additional new compound families and signaling paradigms.
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Affiliation(s)
- Henry H Le
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Chester Jj Wrobel
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Sarah M Cohen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Jingfang Yu
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Heenam Park
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Maximilian J Helf
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Brian J Curtis
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Joseph C Kruempel
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, United States
| | - Pedro Reis Rodrigues
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Patrick J Hu
- Departments of Medicine and Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, United States
| | - Paul W Sternberg
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
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15
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Hoki JS, Le HH, Mellott KE, Zhang YK, Fox BW, Rodrigues PR, Yu Y, Helf MJ, Baccile JA, Schroeder FC. Deep Interrogation of Metabolism Using a Pathway-Targeted Click-Chemistry Approach. J Am Chem Soc 2020; 142:18449-18459. [PMID: 33053303 DOI: 10.1021/jacs.0c06877] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Untargeted metabolomics indicates that the number of unidentified small-molecule metabolites may exceed the number of protein-coding genes for many organisms, including humans, by orders of magnitude. Uncovering the underlying metabolic networks is essential for elucidating the physiological and ecological significance of these biogenic small molecules. Here we develop a click-chemistry-based enrichment strategy, DIMEN (deep interrogation of metabolism via enrichment), that we apply to investigate metabolism of the ascarosides, a family of signaling molecules in the model organism C. elegans. Using a single alkyne-modified metabolite and a solid-phase azide resin that installs a diagnostic moiety for MS/MS-based identification, DIMEN uncovered several hundred novel compounds originating from diverse biosynthetic transformations that reveal unexpected intersection with amino acid, carbohydrate, and energy metabolism. Many of the newly discovered transformations could not be identified or detected by conventional LC-MS analyses without enrichment, demonstrating the utility of DIMEN for deeply probing biochemical networks that generate extensive yet uncharacterized structure space.
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Affiliation(s)
- Jason S Hoki
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Henry H Le
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Karlie E Mellott
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Ying K Zhang
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Bennett W Fox
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Pedro R Rodrigues
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Yan Yu
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Maximilian J Helf
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Joshua A Baccile
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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16
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Tsirvouli E, Touré V, Niederdorfer B, Vázquez M, Flobak Å, Kuiper M. A Middle-Out Modeling Strategy to Extend a Colon Cancer Logical Model Improves Drug Synergy Predictions in Epithelial-Derived Cancer Cell Lines. Front Mol Biosci 2020; 7:502573. [PMID: 33195403 PMCID: PMC7581946 DOI: 10.3389/fmolb.2020.502573] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 09/22/2020] [Indexed: 11/23/2022] Open
Abstract
Cancer is a heterogeneous and complex disease and one of the leading causes of death worldwide. The high tumor heterogeneity between individuals affected by the same cancer type is accompanied by distinct molecular and phenotypic tumor profiles and variation in drug treatment response. In silico modeling of cancer as an aberrantly regulated system of interacting signaling molecules provides a basis to enhance our biological understanding of disease progression, and it offers the means to use computer simulations to test and optimize drug therapy designs on particular cancer types and subtypes. This sets the stage for precision medicine: the design of treatments tailored to individuals or groups of patients based on their tumor-specific molecular cancer profiles. Here, we show how a relatively large manually curated logical model can be efficiently enhanced further by including components highlighted by a multi-omics data analysis of data from Consensus Molecular Subtypes covering colorectal cancer. The model expansion was performed in a pathway-centric manner, following a partitioning of the model into functional subsystems, named modules. The resulting approach constitutes a middle-out modeling strategy enabling a data-driven expansion of a model from a generic and intermediate level of molecular detail to a model better covering relevant processes that are affected in specific cancer subtypes, comprising 183 biological entities and 603 interactions between them, partitioned in 25 functional modules of varying size and structure. We tested this model for its ability to correctly predict drug combination synergies, against a dataset of experimentally determined cell growth responses with 18 drugs in all combinations, on eight cancer cell lines. The results indicate that the extended model had an improved accuracy for drug synergy prediction for the majority of the experimentally tested cancer cell lines, although significant improvements of the model's predictive performance are still needed. Our study demonstrates how a tumor-data driven middle-out approach toward refining a logical model of a biological system can further customize a computer model to represent specific cancer cell lines and provide a basis for identifying synergistic effects of drugs targeting specific regulatory proteins. This approach bridges between preclinical cancer model data and clinical patient data and may thereby ultimately be of help to develop patient-specific in silico models that can steer treatment decisions in the clinic.
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Affiliation(s)
- Eirini Tsirvouli
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Vasundra Touré
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Barbara Niederdorfer
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Miguel Vázquez
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Åsmund Flobak
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
- The Cancer Clinic, St. Olav’s University Hospital, Trondheim, Norway
| | - Martin Kuiper
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
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17
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Abstract
The last few decades have seen the structural and functional elucidation of small-molecule chemical signals called ascarosides in C. elegans. Ascarosides mediate several biological processes in worms, ranging from development, to behavior. These signals are modular in their design architecture, with their building blocks derived from metabolic pathways. Behavioral responses are not only concentration dependent, but also are influenced by the current physiological state of the animal. Cellular and circuit-level analyses suggest that these signals constitute a complex communication system, employing both synergistic molecular elements and sex-specific neuronal circuits governing the response. In this review, we discuss research from multiple laboratories, including our own, that detail how these chemical signals govern several different social behaviors in C. elegans. We propose that the ascaroside repertoire represents a link between diverse metabolic and neurobiological life-history traits and governs the survival of C. elegans in its natural environment.
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Affiliation(s)
- Caroline S Muirhead
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Jagan Srinivasan
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
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18
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Abstract
Caenorhabditis elegans secretes a complex cocktail of small chemicals collectively called ascaroside pheromones which serves as a chemical language for intra-species communication. Subsets of ascarosides have been shown to mediate a broad spectrum of C. elegans behavior and development, such as gender-specific attraction, repulsion, aggregation, olfactory plasticity, and dauer formation. Recent studies show that specific components of ascarosides elicit a rapid avoidance response that allows animals to avoid predators and escape from unfavorable conditions. Moreover, this avoidance behavior is modulated by external conditions, internal states, and previous experience, indicating that pheromone avoidance behavior is highly plastic. In this review, we describe molecular and circuit mechanisms underlying plasticity in pheromone avoidance behavior which pave a way to better understanding circuit mechanisms underlying behavioral plasticity in higher animals, including humans.
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Affiliation(s)
- YongJin Cheon
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Republic of Korea
| | - Hyeonjeong Hwang
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Republic of Korea
| | - Kyuhyung Kim
- Department of Brain and Cognitive Sciences, DGIST, Daegu, Republic of Korea.,Korea Brain Research Institute (KBRI), Daegu, Republic of Korea
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19
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Dong C, Weadick CJ, Truffault V, Sommer RJ. Convergent evolution of small molecule pheromones in Pristionchus nematodes. eLife 2020; 9:55687. [PMID: 32338597 PMCID: PMC7224695 DOI: 10.7554/elife.55687] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/24/2020] [Indexed: 01/05/2023] Open
Abstract
The small molecules that mediate chemical communication between nematodes-so-called 'nematode-derived-modular-metabolites' (NDMMs)-are of major interest because of their ability to regulate development, behavior, and life-history. Pristionchus pacificus nematodes produce an impressive diversity of structurally complex NDMMs, some of which act as primer pheromones that are capable of triggering irreversible developmental switches. Many of these NDMMs have only ever been found in P. pacificus but no attempts have been made to study their evolution by profiling closely related species. This study brings a comparative perspective to the biochemical study of NDMMs through the systematic MS/MS- and NMR-based analysis of exo-metabolomes from over 30 Pristionchus species. We identified 36 novel compounds and found evidence for the convergent evolution of complex NDMMs in separate branches of the Pristionchus phylogeny. Our results demonstrate that biochemical innovation is a recurrent process in Pristionchus nematodes, a pattern that is probably typical across the animal kingdom.
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Affiliation(s)
- Chuanfu Dong
- Department for Integrative Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Cameron J Weadick
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | | | - Ralf J Sommer
- Department for Integrative Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
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20
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Manohar M, Tenjo-Castano F, Chen S, Zhang YK, Kumari A, Williamson VM, Wang X, Klessig DF, Schroeder FC. Plant metabolism of nematode pheromones mediates plant-nematode interactions. Nat Commun 2020; 11:208. [PMID: 31924834 PMCID: PMC6954178 DOI: 10.1038/s41467-019-14104-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 12/13/2019] [Indexed: 12/22/2022] Open
Abstract
Microorganisms and nematodes in the rhizosphere profoundly impact plant health, and small-molecule signaling is presumed to play a central role in plant rhizosphere interactions. However, the nature of the signals and underlying mechanisms are poorly understood. Here we show that the ascaroside ascr#18, a pheromone secreted by plant-parasitic nematodes, is metabolized by plants to generate chemical signals that repel nematodes and reduce infection. Comparative metabolomics of plant tissues and excretions revealed that ascr#18 is converted into shorter side-chained ascarosides that confer repellency. An Arabidopsis mutant defective in two peroxisomal acyl-CoA oxidases does not metabolize ascr#18 and does not repel nematodes, indicating that plants, like nematodes, employ conserved peroxisomal β-oxidation to edit ascarosides and change their message. Our results suggest that plant-editing of nematode pheromones serves as a defense mechanism that acts in parallel to conventional pattern-triggered immunity, demonstrating that plants may actively manipulate chemical signaling of soil organisms.
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Affiliation(s)
| | | | - Shiyan Chen
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Ying K Zhang
- Boyce Thompson Institute, Ithaca, NY, 14853, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Anshu Kumari
- Boyce Thompson Institute, Ithaca, NY, 14853, USA
| | | | - Xiaohong Wang
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Ithaca, NY, 14853, USA
| | - Daniel F Klessig
- Boyce Thompson Institute, Ithaca, NY, 14853, USA.
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA.
| | - Frank C Schroeder
- Boyce Thompson Institute, Ithaca, NY, 14853, USA.
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA.
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21
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Bergame CP, Dong C, Sutour S, von Reuß SH. Epimerization of an Ascaroside-Type Glycolipid Downstream of the Canonical β-Oxidation Cycle in the Nematode Caenorhabditis nigoni. Org Lett 2019; 21:9889-9892. [PMID: 31809061 DOI: 10.1021/acs.orglett.9b03808] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A species-specific ascaroside-type glycolipid was identified in the nematode Caenorhabditis nigoni using HPLC-ESI-(-)-MS/MS precursor ion scanning, HR-MS/MS, and NMR techniques. Its structure containing an l-3,6-dideoxy-lyxo-hexose unit was established by total synthesis. The identification of this novel 4-epi-ascaroside (caenorhabdoside) in C. nigoni along with the previous identification of 2-epi-ascarosides (paratosides) in Pristionchus pacificus indicate that nematodes can generate highly specific signaling molecules by epimerization of the ascarylose building block downstream of the canonical β-oxidation cycle.
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Affiliation(s)
- Célia P Bergame
- Laboratory for Bioanalytical Chemistry, Institute of Chemistry , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
| | - Chuanfu Dong
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany
| | - Sylvain Sutour
- Neuchâtel Platform for Analytical Chemistry (NPAC) , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
| | - Stephan H von Reuß
- Laboratory for Bioanalytical Chemistry, Institute of Chemistry , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland.,Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany.,Neuchâtel Platform for Analytical Chemistry (NPAC) , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
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22
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Selection and gene flow shape niche-associated variation in pheromone response. Nat Ecol Evol 2019; 3:1455-1463. [PMID: 31548647 PMCID: PMC6764921 DOI: 10.1038/s41559-019-0982-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/14/2019] [Indexed: 11/18/2022]
Abstract
From quorum sensing in bacteria to pheromone signaling in social insects, chemical communication mediates interactions among individuals in a local population. In Caenorhabditis elegans, ascaroside pheromones can dictate local population density, in which high levels of pheromones inhibit the reproductive maturation of individuals. Little is known about how natural genetic diversity affects the pheromone responses of individuals from diverse habitats. Here, we show that a niche-associated variation in pheromone receptor genes contributes to natural differences in pheromone responses. We identified putative loss-of-function deletions that impair duplicated pheromone receptor genes (srg-36 and srg-37), which were shown previously to be lost in population-dense laboratory cultures. A common natural deletion in srg-37 arose recently from a single ancestral population that spread throughout the world and underlies reduced pheromone sensitivity across the global C. elegans population. We found that many local populations harbor individuals with wild-type or a deletion allele of srg-37, suggesting that balancing selection has maintained the recent variation in this pheromone receptor gene. The two srg-37 genotypes are associated with niche diversity underlying boom-and-bust population dynamics. We hypothesize that human activities likely contributed to the gene flow and balancing selection of srg-37 variation through facilitating migration of species and providing favorable niche for recently arose srg-37 deletion.
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23
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An excreted small molecule promotes C. elegans reproductive development and aging. Nat Chem Biol 2019; 15:838-845. [PMID: 31320757 PMCID: PMC6650165 DOI: 10.1038/s41589-019-0321-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 05/31/2019] [Indexed: 01/16/2023]
Abstract
Excreted small-molecule signals can bias developmental trajectories and physiology in diverse animal species. However, the chemical identity of these signals remains largely obscure. Here we report identification of an unusual N-acylated glutamine derivative, nacq#1, that accelerates reproductive development and shortens lifespan in C. elegans. Produced predominantly by C. elegans males, nacq#1 hastens onset of sexual maturity in hermaphrodites by promoting exit from the larval dauer diapause and by accelerating late larval development. Even at picomolar concentrations, nacq#1 shortens hermaphrodite lifespan, suggesting a trade-off between reproductive investment and longevity. Acceleration of development by nacq#1 requires chemosensation and depends on three homologs of vertebrate steroid hormone receptors. Unlike ascaroside pheromones, which are restricted to nematodes, fatty acylated amino acid derivatives similar to nacq#1 have been reported from humans and invertebrates, suggesting that related compounds may serve signaling functions throughout Metazoa.
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24
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Dolke F, Dong C, Bandi S, Paetz C, Glauser G, von Reuß SH. Ascaroside Signaling in the Bacterivorous Nematode Caenorhabditis remanei Encodes the Growth Phase of Its Bacterial Food Source. Org Lett 2019; 21:5832-5837. [PMID: 31305087 DOI: 10.1021/acs.orglett.9b01914] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel class of species-specific modular ascarosides that integrate additional fatty acid building blocks was characterized in the nematode Caenorhabditis remanei using a combination of HPLC-ESI-(-)-MS/MS precursor ion scanning, microreactions, HR-MS/MS, MSn, and NMR techniques. The structure of the dominating component carrying a cyclopropyl fatty acid moiety was established by total synthesis. Biogenesis of this female-produced male attractant depends on cyclopropyl fatty acid synthase (cfa), which is expressed in bacteria upon entering their stationary phase.
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Affiliation(s)
- Franziska Dolke
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany
| | - Chuanfu Dong
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany
| | - Siva Bandi
- Laboratory for Bioanalytical Chemistry, Institute of Chemistry , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
| | - Christian Paetz
- Research Group Biosynthesis/NMR , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany
| | - Gaétan Glauser
- Neuchâtel Platform for Analytical Chemistry (NPAC) , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
| | - Stephan H von Reuß
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knöll Straße 8 , D-07745 Jena , Germany.,Laboratory for Bioanalytical Chemistry, Institute of Chemistry , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland.,Neuchâtel Platform for Analytical Chemistry (NPAC) , University of Neuchâtel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
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25
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Jex AR, Gasser RB, Schwarz EM. Transcriptomic Resources for Parasitic Nematodes of Veterinary Importance. Trends Parasitol 2018; 35:72-84. [PMID: 30529253 DOI: 10.1016/j.pt.2018.09.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/17/2018] [Accepted: 09/28/2018] [Indexed: 12/14/2022]
Abstract
Parasitic nematodes are important pathogens of animals, causing diseases that impact on agricultural production worldwide. Research on these worms has been constrained by a lack of genetic and genomic tools. Nonetheless, over the past decade this field has made substantial advances, many of which have been led by transcriptomic sequencing. The present review summarises major transcriptomic studies of veterinary parasitic nematodes in recent years, and comments on overarching themes stemming from this work that inform our understanding of parasitism. Finally, we comment on current, state-of-the-art informatic tools for the analysis of complex worm transcriptomes to extract maximum the molecular information from them.
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Affiliation(s)
- Aaron R Jex
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Melbourne, Victoria, Australia; Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
| | - Robin B Gasser
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Erich M Schwarz
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Melbourne, Victoria, Australia; Cornell University, Ithaca, NY 14850, USA
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26
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Dong C, Reilly DK, Bergame C, Dolke F, Srinivasan J, von Reuss SH. Comparative Ascaroside Profiling of Caenorhabditis Exometabolomes Reveals Species-Specific (ω) and (ω - 2)-Hydroxylation Downstream of Peroxisomal β-Oxidation. J Org Chem 2018; 83:7109-7120. [PMID: 29480728 DOI: 10.1021/acs.joc.8b00094] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chemical communication in nematodes such as the model organism Caenorhabditis elegans is modulated by a variety of glycosides based on the dideoxysugar l-ascarylose. Comparative ascaroside profiling of nematode exometabolome extracts using a GC-EIMS screen reveals that several basic components including ascr#1 (asc-C7), ascr#2 (asc-C6-MK), ascr#3 (asc-ΔC9), ascr#5 (asc-ωC3), and ascr#10 (asc-C9) are highly conserved among the Caenorhabditis. Three novel side chain hydroxylated ascaroside derivatives were exclusively detected in the distantly related C. nigoni and C. afra. Molecular structures of these species-specific putative signaling molecules were elucidated by NMR spectroscopy and confirmed by total synthesis and chemical correlations. Biological activities were evaluated using attraction assays. The identification of (ω)- and (ω - 2)-hydroxyacyl ascarosides demonstrates how GC-EIMS-based ascaroside profiling facilitates the detection of novel ascaroside components and exemplifies how species-specific hydroxylation of ascaroside aglycones downstream of peroxisomal β-oxidation increases the structural diversity of this highly conserved class of nematode signaling molecules.
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Affiliation(s)
- Chuanfu Dong
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knoell Strasse 8 , D-07745 Jena , Germany.,Department for Integrative Evolutionary Biology , Max Planck Institute for Developmental Biology , Max-Planck-Ring 9 , D-72076 Tübingen , Germany
| | - Douglas K Reilly
- Department of Biology and Biotechnology , Worcester Polytechnic Institute , 60 Prescott Street , Worcester , Massachusetts 01605 , United States
| | - Célia Bergame
- Laboratory of Bioanalytical Chemistry , University of Neuchatel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
| | - Franziska Dolke
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knoell Strasse 8 , D-07745 Jena , Germany
| | - Jagan Srinivasan
- Department of Biology and Biotechnology , Worcester Polytechnic Institute , 60 Prescott Street , Worcester , Massachusetts 01605 , United States
| | - Stephan H von Reuss
- Department of Bioorganic Chemistry , Max Planck Institute for Chemical Ecology , Hans-Knoell Strasse 8 , D-07745 Jena , Germany.,Laboratory of Bioanalytical Chemistry , University of Neuchatel , Avenue de Bellevaux 51 , CH-2000 Neuchâtel , Switzerland
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27
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von Reuss SH, Dolke F, Dong C. Ascaroside Profiling of Caenorhabditis elegans Using Gas Chromatography-Electron Ionization Mass Spectrometry. Anal Chem 2017; 89:10570-10577. [PMID: 28866881 DOI: 10.1021/acs.analchem.7b02803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Nematodes such as the model organism Caenorhabditis elegans produce various homologous series of l-ascarylose-derived glycolipids called ascarosides, which include several highly potent signals in intra and interspecies communication as well as cross-kingdom interactions. Given their low concentrations and large number of structurally similar components, mass spectrometric screens based on high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) are commonly employed for ascaroside detection and quantification. Here, we describe a complementary gas chromatography-electron ionization mass spectrometry (GC-EIMS) screen that utilizes an ascarylose-derived K1-fragment ion signal at m/z 130.1 [C6H14OSi]+● to highlight known as well as yet unidentified ascaroside components in TMS-derivatized crude nematode exometabolome extracts. GC-EIMS-based ascaroside profiling of wild-type and mutant C. elegans facilitates the analysis of all basic ascarosides using the same ionization technique while providing excellent resolution for the complete homologous series with side chains ranging from 3 to 33 carbons. Combined screening for m/z 130.1 along with side chain-specific J1 [M - 173]+ and J2 [M - 291]+ fragment ions, as well as additional characteristic marker ions from α-cleavage, enables convenient structure assignment of ca. 200 components from wild-type and peroxisomal β-oxidation mutants including (ω - 1)-linked acyl, enoyl, β-hydroxyacyl, and 2-ketoalkyl ascarosides along with their (ω)-linked or α-methyl isomers and ethanolamide derivatives, as well as 2-hydroxyalkyl ascarosides. Given the widespread availability of GC-MS and its increasing popularity in metabolomics, this method will promote the identification of ascarosides in C. elegans and other nematodes.
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Affiliation(s)
- Stephan H von Reuss
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology , D-07745 Jena, Germany
| | - Franziska Dolke
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology , D-07745 Jena, Germany
| | - Chuanfu Dong
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology , D-07745 Jena, Germany
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28
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Differential Metabolic Profiles during the Developmental Stages of Plant-Parasitic Nematode Meloidogyne incognita. Int J Mol Sci 2017; 18:ijms18071351. [PMID: 28672815 PMCID: PMC5535844 DOI: 10.3390/ijms18071351] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/17/2017] [Accepted: 06/20/2017] [Indexed: 12/27/2022] Open
Abstract
Meloidogyne incognita is a common root-knot nematode with a wide range of plant hosts. We aimed to study the metabolites produced at each stage of the nematode life cycle to understand its development. Metabolites of Meloidogyne incognita were extracted at egg, J2, J3, J4, and female stages and 110 metabolites with available standards were quantified using CE-TOF/MS. Analyses indicated abundance of stage-specific metabolites with the exception of J3 and J4 stages which shared similar metabolic profiles. The egg stage showed increased abundance in glycolysis and energy metabolism related metabolites while the J2 metabolites are associated with tissue formation, motility, and neurotransmission. The J3 and J4 stages indicated amino acid metabolism and urea cycle- related metabolites. The female stage was characterized with polyamine synthesis, antioxidant activity, and synthesis of reproduction related metabolites. Such metabolic profiling helps us understand the dynamic physiological changes related to each developmental stage of the root-knot nematode life cycle.
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Zhang YK, Sanchez-Ayala MA, Sternberg PW, Srinivasan J, Schroeder FC. Improved Synthesis for Modular Ascarosides Uncovers Biological Activity. Org Lett 2017; 19:2837-2840. [PMID: 28513161 PMCID: PMC5533076 DOI: 10.1021/acs.orglett.7b01009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A versatile synthesis of modular ascarosides, a family of signaling molecules from Caenorhabditis elegans and other nematodes, via hydrogenolysis of a cyclic sulfate derived from methyl-α-l-rhamnopyranoside is reported. The route enables selective introduction of different side chains at the 1, 2, and 4 positions of the sugar, as demonstrated for ascarosides from C. elegans and Pristionchus pacificus. Bioassays with synthetic samples of 4'-tigloyl ascaroside mbas#3 revealed its role as an avoidance or dispersal signal.
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Affiliation(s)
- Ying K Zhang
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Marco A Sanchez-Ayala
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Paul W Sternberg
- Howard Hughes Medical Institute and Division of Biology, California Institute of Technology , Pasadena, California 91125, United States
| | - Jagan Srinivasan
- Department of Biology and Biotechnology, Worcester Polytechnic Institute , Worcester, Massachusetts 01609, United States
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
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Hussey R, Stieglitz J, Mesgarzadeh J, Locke TT, Zhang YK, Schroeder FC, Srinivasan S. Pheromone-sensing neurons regulate peripheral lipid metabolism in Caenorhabditis elegans. PLoS Genet 2017; 13:e1006806. [PMID: 28545126 PMCID: PMC5456406 DOI: 10.1371/journal.pgen.1006806] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 06/02/2017] [Accepted: 05/05/2017] [Indexed: 12/03/2022] Open
Abstract
It is now established that the central nervous system plays an important role in regulating whole body metabolism and energy balance. However, the extent to which sensory systems relay environmental information to modulate metabolic events in peripheral tissues has remained poorly understood. In addition, it has been challenging to map the molecular mechanisms underlying discrete sensory modalities with respect to their role in lipid metabolism. In previous work our lab has identified instructive roles for serotonin signaling as a surrogate for food availability, as well as oxygen sensing, in the control of whole body metabolism. In this study, we now identify a role for a pair of pheromone-sensing neurons in regulating fat metabolism in C. elegans, which has emerged as a tractable and highly informative model to study the neurobiology of metabolism. A genetic screen revealed that GPA-3, a member of the Gα family of G proteins, regulates body fat content in the intestine, the major metabolic organ for C. elegans. Genetic and reconstitution studies revealed that the potent body fat phenotype of gpa-3 null mutants is controlled from a pair of neurons called ADL(L/R). We show that cAMP functions as the second messenger in the ADL neurons, and regulates body fat stores via the neurotransmitter acetylcholine, from downstream neurons. We find that the pheromone ascr#3, which is detected by the ADL neurons, regulates body fat stores in a GPA-3-dependent manner. We define here a third sensory modality, pheromone sensing, as a major regulator of body fat metabolism. The pheromone ascr#3 is an indicator of population density, thus we hypothesize that pheromone sensing provides a salient 'denominator' to evaluate the amount of food available within a population and to accordingly adjust metabolic rate and body fat levels. The central nervous system plays a vital role in regulating whole body metabolism and energy balance. However, the precise cellular, genetic and molecular mechanisms underlying these effects remain a major unsolved mystery. C. elegans has emerged as a tractable and highly informative model to study the neurobiology of metabolism. Previously, we have identified instructive roles for serotonin signaling as a surrogate for food availability, as well as oxygen sensing, in the control of whole body metabolism. In our current study we have identified a role for a pair of pheromone-sensing neurons in regulating fat metabolism in C. elegans. cAMP acts as a second messenger in these neurons, and regulates body fat stores via acetylcholine signaling in the nervous system. We find that the population-density-sensing pheromone detected by these neurons regulates body fat stores. Together, we define a third sensory modality, population density sensing, as a major regulator of body fat metabolism.
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Affiliation(s)
- Rosalind Hussey
- Department of Molecular Medicine and Department of Neuroscience, The Scripps Research Institute, La Jolla, California, United States of America
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jon Stieglitz
- Kellogg School of Science and Technology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jaleh Mesgarzadeh
- Department of Molecular Medicine and Department of Neuroscience, The Scripps Research Institute, La Jolla, California, United States of America
- Department of Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Tiffany T. Locke
- Department of Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Ying K. Zhang
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, United States of America
| | - Frank C. Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, United States of America
| | - Supriya Srinivasan
- Department of Molecular Medicine and Department of Neuroscience, The Scripps Research Institute, La Jolla, California, United States of America
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail:
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Schulenburg H, Félix MA. The Natural Biotic Environment of Caenorhabditis elegans. Genetics 2017; 206:55-86. [PMID: 28476862 PMCID: PMC5419493 DOI: 10.1534/genetics.116.195511] [Citation(s) in RCA: 249] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/28/2017] [Indexed: 01/05/2023] Open
Abstract
Organisms evolve in response to their natural environment. Consideration of natural ecological parameters are thus of key importance for our understanding of an organism's biology. Curiously, the natural ecology of the model species Caenorhabditis elegans has long been neglected, even though this nematode has become one of the most intensively studied models in biological research. This lack of interest changed ∼10 yr ago. Since then, an increasing number of studies have focused on the nematode's natural ecology. Yet many unknowns still remain. Here, we provide an overview of the currently available information on the natural environment of C. elegans We focus on the biotic environment, which is usually less predictable and thus can create high selective constraints that are likely to have had a strong impact on C. elegans evolution. This nematode is particularly abundant in microbe-rich environments, especially rotting plant matter such as decomposing fruits and stems. In this environment, it is part of a complex interaction network, which is particularly shaped by a species-rich microbial community. These microbes can be food, part of a beneficial gut microbiome, parasites and pathogens, and possibly competitors. C. elegans is additionally confronted with predators; it interacts with vector organisms that facilitate dispersal to new habitats, and also with competitors for similar food environments, including competitors from congeneric and also the same species. Full appreciation of this nematode's biology warrants further exploration of its natural environment and subsequent integration of this information into the well-established laboratory-based research approaches.
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Affiliation(s)
- Hinrich Schulenburg
- Zoological Institute, Christian-Albrechts Universitaet zu Kiel, 24098 Kiel, Germany
| | - Marie-Anne Félix
- Institut de Biologie de l'Ecole Normale Supérieure, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, École Normale Supérieure, L'université de Recherche Paris Sciences et Lettres, 75005, France
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Gillet FX, Bournaud C, Antonino de Souza Júnior JD, Grossi-de-Sa MF. Plant-parasitic nematodes: towards understanding molecular players in stress responses. ANNALS OF BOTANY 2017; 119:775-789. [PMID: 28087659 PMCID: PMC5378187 DOI: 10.1093/aob/mcw260] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/24/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND Plant-parasitic nematode interactions occur within a vast molecular plant immunity network. Following initial contact with the host plant roots, plant-parasitic nematodes (PPNs) activate basal immune responses. Defence priming involves the release in the apoplast of toxic molecules derived from reactive species or secondary metabolism. In turn, PPNs must overcome the poisonous and stressful environment at the plant-nematode interface. The ability of PPNs to escape this first line of plant immunity is crucial and will determine its virulence. SCOPE Nematodes trigger crucial regulatory cytoprotective mechanisms, including antioxidant and detoxification pathways. Knowledge of the upstream regulatory components that contribute to both of these pathways in PPNs remains elusive. In this review, we discuss how PPNs probably orchestrate cytoprotection to resist plant immune responses, postulating that it may be derived from ancient molecular mechanisms. The review focuses on two transcription factors, DAF-16 and SKN-1 , which are conserved in the animal kingdom and are central regulators of cell homeostasis and immune function. Both regulate the unfolding protein response and the antioxidant and detoxification pathways. DAF-16 and SKN-1 target a broad spectrum of Caenorhabditis elegans genes coding for numerous protein families present in the secretome of PPNs. Moreover, some regulatory elements of DAF-16 and SKN-1 from C. elegans have already been identified as important genes for PPN infection. CONCLUSION DAF-16 and SKN-1 genes may play a pivotal role in PPNs during parasitism. In the context of their hub status and mode of regulation, we suggest alternative strategies for control of PPNs through RNAi approaches.
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Affiliation(s)
- François-Xavier Gillet
- Embrapa Genetic Resources and Biotechnology, PqEB Final Av. W/5 Norte, CEP 70·770-900, Brasília, DF, Brazil
| | - Caroline Bournaud
- Embrapa Genetic Resources and Biotechnology, PqEB Final Av. W/5 Norte, CEP 70·770-900, Brasília, DF, Brazil
| | | | - Maria Fatima Grossi-de-Sa
- Embrapa Genetic Resources and Biotechnology, PqEB Final Av. W/5 Norte, CEP 70·770-900, Brasília, DF, Brazil
- Catholic University of Brasilia, Brasília-DF, Brazil
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Markov GV, Meyer JM, Panda O, Artyukhin AB, Claaßen M, Witte H, Schroeder FC, Sommer RJ. Functional Conservation and Divergence of daf-22 Paralogs in Pristionchus pacificus Dauer Development. Mol Biol Evol 2016; 33:2506-14. [PMID: 27189572 DOI: 10.1093/molbev/msw090] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Small-molecule signaling in nematode dauer formation has emerged as a major model to study chemical communication in development and evolution. Developmental arrest as nonfeeding and stress-resistant dauer larvae represents the major survival and dispersal strategy. Detailed studies in Caenorhabditis elegans and Pristionchus pacificus revealed that small-molecule communication changes rapidly in evolution resulting in extreme structural diversity of small-molecule compounds. In C. elegans, a blend of ascarosides constitutes the dauer pheromone, whereas the P. pacificus dauer pheromone includes additional paratosides and integrates building blocks from diverse primary metabolic pathways. Despite this complexity of small-molecule structures and functions, little is known about the biosynthesis of small molecules in nematodes outside C. elegans Here, we show that the genes encoding enzymes of the peroxisomal β-oxidation pathway involved in small-molecule biosynthesis evolve rapidly, including gene duplications and domain switching. The thiolase daf-22, the most downstream factor in C. elegans peroxisomal β-oxidation, has duplicated in P. pacificus, resulting in Ppa-daf-22.1, which still contains the sterol-carrier-protein (SCP) domain that was lost in C. elegans daf-22, and Ppa-daf-22.2. Using the CRISPR/Cas9 system, we induced mutations in both P. pacificus daf-22 genes and identified an unexpected complexity of functional conservation and divergence. Under well-fed conditions, ascaroside biosynthesis proceeds exclusively via Ppa-daf-22.1 In contrast, starvation conditions induce Ppa-daf-22.2 activity, resulting in the production of a specific subset of ascarosides. Gene expression studies indicate a reciprocal up-regulation of both Ppa-daf-22 genes, which is, however, independent of starvation. Thus, our study reveals an unexpected functional complexity of dauer development and evolution.
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Affiliation(s)
- Gabriel V Markov
- Max-Planck Institute for Developmental Biology, Spemannstrasse 37, Tübingen, Germany
| | - Jan M Meyer
- Max-Planck Institute for Developmental Biology, Spemannstrasse 37, Tübingen, Germany
| | - Oishika Panda
- Boyce Thompson Institute, Cornell University Department of Chemistry and Chemical Biology, Cornell University
| | | | - Marc Claaßen
- Max-Planck Institute for Developmental Biology, Spemannstrasse 37, Tübingen, Germany
| | - Hanh Witte
- Max-Planck Institute for Developmental Biology, Spemannstrasse 37, Tübingen, Germany
| | - Frank C Schroeder
- Boyce Thompson Institute, Cornell University Department of Chemistry and Chemical Biology, Cornell University
| | - Ralf J Sommer
- Max-Planck Institute for Developmental Biology, Spemannstrasse 37, Tübingen, Germany
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Holbein J, Grundler FMW, Siddique S. Plant basal resistance to nematodes: an update. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2049-61. [PMID: 26842982 DOI: 10.1093/jxb/erw005] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Most plant-parasitic nematodes are obligate biotrophs feeding on the roots of their hosts. Whereas ectoparasites remain on the root surface and feed on the outer cell layers, endoparasitic nematodes enter the host to parasitize cells around or within the central cylinder. Nematode invasion and feeding causes tissue damage which may, in turn, lead to the activation of host basal defence responses. Hitherto, research interests in plant-nematode interaction have emphasized effector-triggered immunity rather than basal plant defence responses. However, some recent investigations suggest that basal defence pathways are not only activated but also play an important role in determining interaction outcomes. In this review we discuss the major findings and point out future directions to dissect the molecular mechanisms underlying plant basal defence to nematodes further.
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Affiliation(s)
- Julia Holbein
- Rheinische Friedrich-Wilhelms-University of Bonn, INRES - Molecular Phytomedicine, Karlrobert-Kreiten-Straße 13, D-53115 Bonn, Germany
| | - Florian M W Grundler
- Rheinische Friedrich-Wilhelms-University of Bonn, INRES - Molecular Phytomedicine, Karlrobert-Kreiten-Straße 13, D-53115 Bonn, Germany
| | - Shahid Siddique
- Rheinische Friedrich-Wilhelms-University of Bonn, INRES - Molecular Phytomedicine, Karlrobert-Kreiten-Straße 13, D-53115 Bonn, Germany
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35
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Witting M, Schmitt-Kopplin P. The Caenorhabditis elegans lipidome. Arch Biochem Biophys 2016; 589:27-37. [DOI: 10.1016/j.abb.2015.06.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/02/2015] [Accepted: 06/04/2015] [Indexed: 12/30/2022]
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Sommer RJ, Mayer MG. Toward a Synthesis of Developmental Biology with Evolutionary Theory and Ecology. Annu Rev Cell Dev Biol 2015; 31:453-71. [DOI: 10.1146/annurev-cellbio-102314-112451] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ralf J. Sommer
- Department for Evolutionary Biology, Max-Planck Institute for Developmental Biology, 72076 Tübingen, Germany;
| | - Melanie G. Mayer
- Department for Evolutionary Biology, Max-Planck Institute for Developmental Biology, 72076 Tübingen, Germany;
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37
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Abstract
Chemical ecology elucidates the nature and role of natural products as mediators of organismal interactions. The emerging techniques that can be summarized under the concept of metabolomics provide new opportunities to study such environmentally relevant signaling molecules. Especially comparative tools in metabolomics enable the identification of compounds that are regulated during interaction situations and that might play a role as e.g. pheromones, allelochemicals or in induced and activated defenses. This approach helps overcoming limitations of traditional bioassay-guided structure elucidation approaches. But the power of metabolomics is not limited to the comparison of metabolic profiles of interacting partners. Especially the link to other -omics techniques helps to unravel not only the compounds in question but the entire biosynthetic and genetic re-wiring, required for an ecological response. This review comprehensively highlights successful applications of metabolomics in chemical ecology and discusses existing limitations of these novel techniques. It focuses on recent developments in comparative metabolomics and discusses the use of metabolomics in the systems biology of organismal interactions. It also outlines the potential of large metabolomics initiatives for model organisms in the field of chemical ecology.
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Affiliation(s)
- Constanze Kuhlisch
- Friedrich Schiller University, Institute of Inorganic and Analytical Chemistry, Lessingstr. 8, D-07743 Jena, Germany.
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38
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Manosalva P, Manohar M, von Reuss SH, Chen S, Koch A, Kaplan F, Choe A, Micikas RJ, Wang X, Kogel KH, Sternberg PW, Williamson VM, Schroeder FC, Klessig DF. Conserved nematode signalling molecules elicit plant defenses and pathogen resistance. Nat Commun 2015; 6:7795. [PMID: 26203561 PMCID: PMC4525156 DOI: 10.1038/ncomms8795] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 06/10/2015] [Indexed: 01/27/2023] Open
Abstract
Plant-defense responses are triggered by perception of conserved microbe-associated molecular patterns (MAMPs), for example, flagellin or peptidoglycan. However, it remained unknown whether plants can detect conserved molecular patterns derived from plant-parasitic animals, including nematodes. Here we show that several genera of plant-parasitic nematodes produce small molecules called ascarosides, an evolutionarily conserved family of nematode pheromones. Picomolar to micromolar concentrations of ascr#18, the major ascaroside in plant-parasitic nematodes, induce hallmark defense responses including the expression of genes associated with MAMP-triggered immunity, activation of mitogen-activated protein kinases, as well as salicylic acid- and jasmonic acid-mediated defense signalling pathways. Ascr#18 perception increases resistance in Arabidopsis, tomato, potato and barley to viral, bacterial, oomycete, fungal and nematode infections. These results indicate that plants recognize ascarosides as a conserved molecular signature of nematodes. Using small-molecule signals such as ascarosides to activate plant immune responses has potential utility to improve economic and environmental sustainability of agriculture.
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Affiliation(s)
- Patricia Manosalva
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
- Department of Plant Pathology and Microbiology, University of California Riverside, Riverside, California 92521, USA
| | - Murli Manohar
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | | | - Shiyan Chen
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853, USA
| | - Aline Koch
- Research Centre for BioSystems, Land Use, and Nutrition, Justus Liebig University, Giessen D-35392, Germany
| | - Fatma Kaplan
- Kaplan Schiller Research, LLC, Gainesville, Florida 32604, USA
| | - Andrea Choe
- Howard Hughes Medical Institute and Biology Division, California Institute of Technology, Pasadena, California 91125, USA
| | - Robert J. Micikas
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | - Xiaohong Wang
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853, USA
- Robert W. Holley Center for Agriculture and Health, US Department of Agricultural Research Service, Ithaca, New York 14853, USA
| | - Karl-Heinz Kogel
- Research Centre for BioSystems, Land Use, and Nutrition, Justus Liebig University, Giessen D-35392, Germany
| | - Paul W. Sternberg
- Howard Hughes Medical Institute and Biology Division, California Institute of Technology, Pasadena, California 91125, USA
| | - Valerie M. Williamson
- Department of Plant Pathology, University of California, Davis, California 95616, USA
| | - Frank C. Schroeder
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | - Daniel F. Klessig
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
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Manosalva P, Manohar M, von Reuss SH, Chen S, Koch A, Kaplan F, Choe A, Micikas RJ, Wang X, Kogel KH, Sternberg PW, Williamson VM, Schroeder FC, Klessig DF. Conserved nematode signalling molecules elicit plant defenses and pathogen resistance. Nat Commun 2015. [PMID: 26203561 DOI: 10.1038/ncomss8795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
Plant-defense responses are triggered by perception of conserved microbe-associated molecular patterns (MAMPs), for example, flagellin or peptidoglycan. However, it remained unknown whether plants can detect conserved molecular patterns derived from plant-parasitic animals, including nematodes. Here we show that several genera of plant-parasitic nematodes produce small molecules called ascarosides, an evolutionarily conserved family of nematode pheromones. Picomolar to micromolar concentrations of ascr#18, the major ascaroside in plant-parasitic nematodes, induce hallmark defense responses including the expression of genes associated with MAMP-triggered immunity, activation of mitogen-activated protein kinases, as well as salicylic acid- and jasmonic acid-mediated defense signalling pathways. Ascr#18 perception increases resistance in Arabidopsis, tomato, potato and barley to viral, bacterial, oomycete, fungal and nematode infections. These results indicate that plants recognize ascarosides as a conserved molecular signature of nematodes. Using small-molecule signals such as ascarosides to activate plant immune responses has potential utility to improve economic and environmental sustainability of agriculture.
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Affiliation(s)
- Patricia Manosalva
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
- Department of Plant Pathology and Microbiology, University of California Riverside, Riverside, California 92521, USA
| | - Murli Manohar
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | | | - Shiyan Chen
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853, USA
| | - Aline Koch
- Research Centre for BioSystems, Land Use, and Nutrition, Justus Liebig University, Giessen D-35392, Germany
| | - Fatma Kaplan
- Kaplan Schiller Research, LLC, Gainesville, Florida 32604, USA
| | - Andrea Choe
- Howard Hughes Medical Institute and Biology Division, California Institute of Technology, Pasadena, California 91125, USA
| | - Robert J Micikas
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | - Xiaohong Wang
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853, USA
- Robert W. Holley Center for Agriculture and Health, US Department of Agricultural Research Service, Ithaca, New York 14853, USA
| | - Karl-Heinz Kogel
- Research Centre for BioSystems, Land Use, and Nutrition, Justus Liebig University, Giessen D-35392, Germany
| | - Paul W Sternberg
- Howard Hughes Medical Institute and Biology Division, California Institute of Technology, Pasadena, California 91125, USA
| | - Valerie M Williamson
- Department of Plant Pathology, University of California, Davis, California 95616, USA
| | - Frank C Schroeder
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
| | - Daniel F Klessig
- Boyce Thompson Institute for Plant Research, Ithaca, New York 14853, USA
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Quantifying intracellular metabolites in yeast using a matrix with minimal interference from naturally occurring analytes. Anal Biochem 2015; 487:17-26. [PMID: 26142219 DOI: 10.1016/j.ab.2015.06.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 12/13/2022]
Abstract
For quantification of intracellular metabolites, mass spectrometry combined with liquid chromatography, capillary electrophoresis, or gas chromatography is currently the method of choice, especially when combined with stable isotope-labeled internal standards (SIL-ISs). Due to the difficulties in finding a biological matrix free of intracellular metabolites, a standard addition based validation is needed. Here, we present an alternative by producing a matrix with minimal signal interferences on both the analytes and their SIL-ISs. The matrix was obtained by cultivating Saccharomyces cerevisiae in [(13)C6]glucose/nonlabeled glucose (50:50, w/w) growth medium. The areas of both (12)C6 and (13)C6 fractions of ATP in the matrix were measured to be 2% of the sum of the areas of all ATP isotopes detected. The matrix allowed for spiking of both the nonlabeled and SIL-ISs and more straightforward validation. The intra- and inter-day accuracy and precision were ⩾80% and ⩽20%, respectively. The methodology was used for quantification of nucleotides, coenzymes, and redox compounds from Saccharomyces cerevisiae. The determined energy charge ratio was 0.9, whereas the Mal-CoA/Ac-CoA ratio was 0.04. The analysis of the redox compounds was challenging due to the oxidation of NADH and NADPH, when dissolved in water or tributylamine. The oxidation was reduced by dissolving them in ammonium acetate solution (pH 8.0).
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von Reuss SH, Schroeder FC. Combinatorial chemistry in nematodes: modular assembly of primary metabolism-derived building blocks. Nat Prod Rep 2015; 32:994-1006. [PMID: 26059053 PMCID: PMC4884655 DOI: 10.1039/c5np00042d] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The nematode Caenorhabditis elegans was the first animal to have its genome fully sequenced and has become an important model organism for biomedical research. However, like many other animal model systems, its metabolome remained largely uncharacterized, until recent investigations demonstrated the importance of small molecule-based signalling cascades for virtually every aspect of nematode biology. These studies have revealed that nematodes are amazingly skilled chemists: using simple building blocks from conserved primary metabolism and a strategy of modular assembly, C. elegans and other nematode species create complex molecular architectures to regulate their development and behaviour. These nematode-derived modular metabolites (NDMMs) are based on the dideoxysugars ascarylose or paratose, which serve as scaffolds for attachment of moieties from lipid, amino acid, carbohydrate, citrate, and nucleoside metabolism. Mutant screens and comparative metabolomics based on NMR spectroscopy and MS have so-far revealed several 100 different ascarylose ("ascarosides") and a few paratose ("paratosides") derivatives, many of which represent potent signalling molecules that can be active at femtomolar levels, regulating development, behaviour, body shape, and many other life history traits. NDMM biosynthesis appears to be carefully regulated as assembly of different modules proceeds with very high specificity. Preliminary biosynthetic studies have confirmed the primary metabolism origin of some NDMM building blocks, whereas the mechanisms that underlie their highly specific assembly are not understood. Considering their functions and biosynthetic origin, NDMMs represent a new class of natural products that cannot easily be classified as "primary" or "secondary". We believe that the identification of new variants of primary metabolism-derived structures that serve important signalling functions in C. elegans and other nematodes provides a strong incentive for a comprehensive re-analysis of metabolism in higher animals, including humans.
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Affiliation(s)
- Stephan H. von Reuss
- Max Planck Institute for Chemical Ecology, Department of Bioorganic Chemistry, Jena, Germany
| | - Frank C. Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
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42
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Mayer MG, Rödelsperger C, Witte H, Riebesell M, Sommer RJ. The Orphan Gene dauerless Regulates Dauer Development and Intraspecific Competition in Nematodes by Copy Number Variation. PLoS Genet 2015; 11:e1005146. [PMID: 26087034 PMCID: PMC4473527 DOI: 10.1371/journal.pgen.1005146] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/13/2015] [Indexed: 12/04/2022] Open
Abstract
Many nematodes form dauer larvae when exposed to unfavorable conditions, representing an example of phenotypic plasticity and a major survival and dispersal strategy. In Caenorhabditis elegans, the regulation of dauer induction is a model for pheromone, insulin, and steroid-hormone signaling. Recent studies in Pristionchus pacificus revealed substantial natural variation in various aspects of dauer development, i.e. pheromone production and sensing and dauer longevity and fitness. One intriguing example is a strain from Ohio, having extremely long-lived dauers associated with very high fitness and often forming the most dauers in response to other strains' pheromones, including the reference strain from California. While such examples have been suggested to represent intraspecific competition among strains, the molecular mechanisms underlying these dauer-associated patterns are currently unknown. We generated recombinant-inbred-lines between the Californian and Ohioan strains and used quantitative-trait-loci analysis to investigate the molecular mechanism determining natural variation in dauer development. Surprisingly, we discovered that the orphan gene dauerless controls dauer formation by copy number variation. The Ohioan strain has one dauerless copy causing high dauer formation, whereas the Californian strain has two copies, resulting in strongly reduced dauer formation. Transgenic animals expressing multiple copies do not form dauers. dauerless is exclusively expressed in CAN neurons, and both CAN ablation and dauerless mutations increase dauer formation. Strikingly, dauerless underwent several duplications and acts in parallel or downstream of steroid-hormone signaling but upstream of the nuclear-hormone-receptor daf-12. We identified the novel or fast-evolving gene dauerless as inhibitor of dauer development. Our findings reveal the importance of gene duplications and copy number variations for orphan gene function and suggest daf-12 as major target for dauer regulation. We discuss the consequences of the novel vs. fast-evolving nature of orphans for the evolution of developmental networks and their role in natural variation and intraspecific competition.
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Affiliation(s)
- Melanie G. Mayer
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Christian Rödelsperger
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Hanh Witte
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Metta Riebesell
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Ralf J. Sommer
- Department of Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
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Yim JJ, Bose N, Meyer JM, Sommer RJ, Schroeder FC. Nematode signaling molecules derived from multimodular assembly of primary metabolic building blocks. Org Lett 2015; 17:1648-51. [PMID: 25782998 PMCID: PMC4878434 DOI: 10.1021/acs.orglett.5b00329] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In the nematode model organisms Caenorhabditis elegans and Pristionchus pacificus, a new class of natural products based on modular assembly of primary-metabolism-derived building blocks control organismal development and behavior. We report identification and biological activities of the first pentamodular metabolite, pasa#9, and the 8-oxoadenine-containing npar#3 from P. pacificus. These structures suggest co-option of nucleoside and tryptophan metabolic pathways for the biosynthesis of endogenous metabolite libraries that transcend the dichotomy between "primary" and "secondary" metabolism.
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Affiliation(s)
- Joshua J. Yim
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
- Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tubingen 72076, Germany
| | - Neelanjan Bose
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jan M. Meyer
- Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tubingen 72076, Germany
| | - Ralf J. Sommer
- Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Tubingen 72076, Germany
| | - Frank C. Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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