1
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Bhar S, Yoon CS, Mai K, Han J, Prajapati DV, Wang Y, Steffen CL, Bailey LS, Basso KB, Butcher RA. An acyl-CoA thioesterase is essential for the biosynthesis of a key dauer pheromone in C. elegans. Cell Chem Biol 2024; 31:1011-1022.e6. [PMID: 38183989 PMCID: PMC11102344 DOI: 10.1016/j.chembiol.2023.12.006] [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: 04/03/2023] [Revised: 09/02/2023] [Accepted: 12/10/2023] [Indexed: 01/08/2024]
Abstract
Methyl ketone (MK)-ascarosides represent essential components of several pheromones in Caenorhabditis elegans, including the dauer pheromone, which triggers the stress-resistant dauer larval stage, and the male-attracting sex pheromone. Here, we identify an acyl-CoA thioesterase, ACOT-15, that is required for the biosynthesis of MK-ascarosides. We propose a model in which ACOT-15 hydrolyzes the β-keto acyl-CoA side chain of an ascaroside intermediate during β-oxidation, leading to decarboxylation and formation of the MK. Using comparative metabolomics, we identify additional ACOT-15-dependent metabolites, including an unusual piperidyl-modified ascaroside, reminiscent of the alkaloid pelletierine. The β-keto acid generated by ACOT-15 likely couples to 1-piperideine to produce the piperidyl ascaroside, which is much less dauer-inducing than the dauer pheromone, asc-C6-MK (ascr#2, 1). The bacterial food provided influences production of the piperidyl ascaroside by the worm. Our work shows how the biosynthesis of MK- and piperidyl ascarosides intersect and how bacterial food may impact chemical signaling in the worm.
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Affiliation(s)
- Subhradeep Bhar
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Chi-Su Yoon
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Kevin Mai
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Jungsoo Han
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Dilip V Prajapati
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Yuting Wang
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Candy L Steffen
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Laura S Bailey
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Kari B Basso
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Rebecca A Butcher
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA.
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2
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Lee D, Fox B, Palomino D, Panda O, Tenjo F, Koury E, Evans K, Stevens L, Rodrigues P, Kolodziej A, Schroeder F, Andersen E. Natural genetic variation in the pheromone production of C. elegans. Proc Natl Acad Sci U S A 2023; 120:e2221150120. [PMID: 37339205 PMCID: PMC10293855 DOI: 10.1073/pnas.2221150120] [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: 12/15/2022] [Accepted: 05/10/2023] [Indexed: 06/22/2023] Open
Abstract
From bacterial quorum sensing to human language, communication is essential for social interactions. Nematodes produce and sense pheromones to communicate among individuals and respond to environmental changes. These signals are encoded by different types and mixtures of ascarosides, whose modular structures further enhance the diversity of this nematode pheromone language. Interspecific and intraspecific differences in this ascaroside pheromone language have been described previously, but the genetic basis and molecular mechanisms underlying the variation remain largely unknown. Here, we analyzed natural variation in the production of 44 ascarosides across 95 wild Caenorhabditis elegans strains using high-performance liquid chromatography coupled to high-resolution mass spectrometry. We discovered wild strains defective in the production of specific subsets of ascarosides (e.g., the aggregation pheromone icas#9) or short- and medium-chain ascarosides, as well as inversely correlated patterns between the production of two major classes of ascarosides. We investigated genetic variants that are significantly associated with the natural differences in the composition of the pheromone bouquet, including rare genetic variants in key enzymes participating in ascaroside biosynthesis, such as the peroxisomal 3-ketoacyl-CoA thiolase, daf-22, and the carboxylesterase cest-3. Genome-wide association mappings revealed genomic loci harboring common variants that affect ascaroside profiles. Our study yields a valuable dataset for investigating the genetic mechanisms underlying the evolution of chemical communication.
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Affiliation(s)
- Daehan Lee
- Department of Molecular Biosciences, Northwestern University, Evanston, IL60208
- Department of Biology, Kyung Hee University, Seoul02447, Republic of Korea
- Department of Biological Sciences, Sungkyunkwan University, Suwon16419, Republic of Korea
| | - Bennett W. Fox
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Diana Fajardo Palomino
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Oishika Panda
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Francisco J. Tenjo
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Emily J. Koury
- Department of Molecular Biosciences, Northwestern University, Evanston, IL60208
| | - Kathryn S. Evans
- Department of Molecular Biosciences, Northwestern University, Evanston, IL60208
| | - Lewis Stevens
- Department of Molecular Biosciences, Northwestern University, Evanston, IL60208
- Tree of Life, Wellcome Sanger Institute, CambridgeCB10 1SA, United Kingdom
| | - Pedro R. Rodrigues
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Aiden R. Kolodziej
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Frank C. Schroeder
- Boyce Thompson Institute, Cornell University, Ithaca, NY14850
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY14850
| | - Erik C. Andersen
- Department of Molecular Biosciences, Northwestern University, Evanston, IL60208
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3
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Adams S, Pathak P, Kittelmann M, Jones ARC, Mallon EB, Pires-daSilva A. Sexual morph specialisation in a trioecious nematode balances opposing selective forces. Sci Rep 2022; 12:6402. [PMID: 35431314 PMCID: PMC9013718 DOI: 10.1038/s41598-022-09900-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/10/2022] [Indexed: 11/27/2022] Open
Abstract
The coexistence of different mating strategies, whereby a species can reproduce both by selfing and outcrossing, is an evolutionary enigma. Theory predicts two predominant stable mating states: outcrossing with strong inbreeding depression or selfing with weak inbreeding depression. As these two mating strategies are subject to opposing selective forces, mixed breeding systems are thought to be a rare transitory state yet can persist even after multiple speciation events. We hypothesise that if each mating strategy plays a distinctive role during some part of the species life history, opposing selective pressures could be balanced, permitting the stable co-existence of selfing and outcrossing sexual morphs. In this scenario, we would expect each morph to be specialised in their respective roles. Here we show, using behavioural, physiological and gene expression studies, that the selfing (hermaphrodite) and outcrossing (female) sexual morphs of the trioecious nematode Auanema freiburgensis have distinct adaptations optimised for their different roles during the life cycle. A. freiburgensis hermaphrodites are known to be produced under stressful conditions and are specialised for dispersal to new habitat patches. Here we show that they exhibit metabolic and intestinal changes enabling them to meet the cost of dispersal and reproduction. In contrast, A. freiburgensis females are produced in favourable conditions and facilitate rapid population growth. We found that females compensate for the lack of reproductive assurance by reallocating resources from intestinal development to mate-finding behaviour. The specialisation of each mating system for its role in the life cycle could balance opposing selective forces allowing the stable maintenance of both mating systems in A. freiburgensis.
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Affiliation(s)
- Sally Adams
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
| | - Prachi Pathak
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Maike Kittelmann
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington Campus, Oxford, OX3 0BP, UK
| | - Alun R C Jones
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
| | - Eamonn B Mallon
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, LE1 7RH, UK
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4
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Gao C, Li Q, Yu J, Li S, Cui Q, Hu X, Chen L, Zhang SO. Endocrine pheromones couple fat rationing to dauer diapause through HNF4α nuclear receptors. SCIENCE CHINA-LIFE SCIENCES 2021; 64:2153-2174. [PMID: 34755252 DOI: 10.1007/s11427-021-2016-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 09/30/2021] [Indexed: 12/21/2022]
Abstract
Developmental diapause is a widespread strategy for animals to survive seasonal starvation and environmental harshness. Diapaused animals often ration body fat to generate a basal level of energy for enduring survival. How diapause and fat rationing are coupled, however, is poorly understood. The nematode Caenorhabditis elegans excretes pheromones to the environment to induce a diapause form called dauer larva. Through saturated forward genetic screens and CRISPR knockout, we found that dauer pheromones feed back to repress the transcription of ACOX-3, MAOC-1, DHS-28, DAF-22 (peroxisomal β-oxidation enzymes dually involved in pheromone synthesis and fat burning), ALH-4 (aldehyde dehydrogenase for pheromone synthesis), PRX-10 and PRX-11 (peroxisome assembly and proliferation factors). Dysfunction of these pheromone enzymes and factors relieves the repression. Surprisingly, transcription is repressed not by pheromones excreted but by pheromones endogenous to each animal. The endogenous pheromones regulate the nuclear translocation of HNF4α family nuclear receptor NHR-79 and its co-receptor NHR-49, and, repress transcription through the two receptors. The feedback repression maintains pheromone homeostasis, increases fat storage, decreases fat burning, and prolongs dauer lifespan. Thus, the exocrine dauer pheromones possess an unexpected endocrine function to mediate a peroxisome-nucleus crosstalk, coupling dauer diapause to fat rationing.
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Affiliation(s)
- Cheng Gao
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Qi Li
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Jialei Yu
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Shiwei Li
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Qingpo Cui
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Xiao Hu
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Lifeng Chen
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Shaobing O Zhang
- Laboratory of Metabolic Genetics, College of Life Sciences, Capital Normal University, Beijing, 100048, China.
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5
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Rackles E, Witting M, Forné I, Zhang X, Zacherl J, Schrott S, Fischer C, Ewbank JJ, Osman C, Imhof A, Rolland SG. Reduced peroxisomal import triggers peroxisomal retrograde signaling. Cell Rep 2021; 34:108653. [PMID: 33472070 DOI: 10.1016/j.celrep.2020.108653] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/06/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
Maintaining organelle function in the face of stress is known to involve organelle-specific retrograde signaling. Using Caenorhabditis elegans, we present evidence of the existence of such retrograde signaling for peroxisomes, which we define as the peroxisomal retrograde signaling (PRS). Specifically, we show that peroxisomal import stress caused by knockdown of the peroxisomal matrix import receptor prx-5/PEX5 triggers NHR-49/peroxisome proliferator activated receptor alpha (PPARα)- and MDT-15/MED15-dependent upregulation of the peroxisomal Lon protease lonp-2/LONP2 and the peroxisomal catalase ctl-2/CAT. Using proteomic and transcriptomic analyses, we show that proteins involved in peroxisomal lipid metabolism and immunity are also upregulated upon prx-5(RNAi). While the PRS can be triggered by perturbation of peroxisomal β-oxidation, we also observed hallmarks of PRS activation upon infection with Pseudomonas aeruginosa. We propose that the PRS, in addition to a role in lipid metabolism homeostasis, may act as a surveillance mechanism to protect against pathogens.
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Affiliation(s)
- Elisabeth Rackles
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany
| | - Michael Witting
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany; Chair of Analytical Food Chemistry, TUM School of Life Sciences, Technical University of Munich, Maximus-von-Imhof-Forum 2, 85354 Freising, Germany
| | - Ignasi Forné
- Protein Analysis Unit, BioMedical Center, Faculty of Medicine, Ludwig Maximilian University of Munich, Großhadernerstr. 9, 82152 Martinsried, Germany
| | - Xing Zhang
- Aix Marseille Univ, CNRS, INSERM, CIML, Turing Centre for Living Systems, Marseille, France
| | - Judith Zacherl
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany
| | - Simon Schrott
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany
| | - Christian Fischer
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany
| | - Jonathan J Ewbank
- Aix Marseille Univ, CNRS, INSERM, CIML, Turing Centre for Living Systems, Marseille, France
| | - Christof Osman
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany
| | - Axel Imhof
- Protein Analysis Unit, BioMedical Center, Faculty of Medicine, Ludwig Maximilian University of Munich, Großhadernerstr. 9, 82152 Martinsried, Germany
| | - Stéphane G Rolland
- Faculty of Biology, Ludwig Maximilian University of Munich, 82152 Martinsried, Germany.
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6
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Zhang B, Zhao L, Ning J, Wickham JD, Tian H, Zhang X, Yang M, Wang X, Sun J. miR-31-5p regulates cold acclimation of the wood-boring beetle Monochamus alternatus via ascaroside signaling. BMC Biol 2020; 18:184. [PMID: 33246464 PMCID: PMC7697373 DOI: 10.1186/s12915-020-00926-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 11/11/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Survival to cold stress in insects living in temperate environments requires the deployment of strategies that lead to physiological changes involved in freeze tolerance or freeze avoidance. These strategies may consist of, for instance, the induction of metabolic depression, accumulation of cryoprotectants, or the production of antifreeze proteins, however, little is known about the way such mechanisms are regulated and the signals involved in their activation. Ascarosides are signaling molecules usually known to regulate nematode behavior and development, whose expression was recently found to relate to thermal plasticity in the Japanese pine sawyer beetle Monochamus alternatus. Accumulating evidence also points to miRNAs as another class of regulators differentially expressed in response to cold stress, which are predicted to target genes involved in cold adaptation of insects. Here, we demonstrate a novel pathway involved in insect cold acclimation, through miRNA-mediated regulation of ascaroside function. RESULTS We initially discovered that experimental cold acclimation can enhance the beetle's cold hardiness. Through screening and functional verification, we found miR-31-5p, upregulated under cold stress, significantly contributes to this enhancement. Mechanistically, miR-31-5p promotes production of an ascaroside (asc-C9) in the beetle by negatively targeting the rate-limiting enzyme, acyl-CoA oxidase in peroxisomal β-oxidation cycles. Feeding experiments with synthetic asc-C9 suggests it may serve as a signal to promote cold acclimation through metabolic depression and accumulation of cryoprotectants with specific gene expression patterns. CONCLUSIONS Our results point to important roles of miRNA-mediated regulation of ascaroside function in insect cold adaptation. This enhanced cold tolerance may allow higher survival of M. alternatus in winter and be pivotal in shaping its wide distribution range, greatly expanding the threat of pine wilt disease, and thus can also inspire the development of ascaroside-based pest management strategies.
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Affiliation(s)
- Bin Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 10049, China
| | - Lilin Zhao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 10049, China
| | - Jing Ning
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jacob D Wickham
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Haokai Tian
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 10049, China
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Meiling Yang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiangming Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jianghua Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 10049, China.
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7
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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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8
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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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9
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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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10
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Faghih N, Bhar S, Zhou Y, Dar AR, Mai K, Bailey LS, Basso KB, Butcher RA. A Large Family of Enzymes Responsible for the Modular Architecture of Nematode Pheromones. J Am Chem Soc 2020; 142:13645-13650. [PMID: 32702987 DOI: 10.1021/jacs.0c04223] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The nematode Caenorhabditis elegans produces a broad family of pheromones, known as the ascarosides, that are modified with a variety of groups derived from primary metabolism. These modifications are essential for the diverse activities of the ascarosides in development and various behaviors, including attraction, aggregation, avoidance, and foraging. The mechanism by which these different groups are added to the ascarosides is poorly understood. Here, we identify a family of over 30 enzymes, which are homologous to mammalian carboxylesterase (CES) enzymes, and show that a number of these enzymes are responsible for the selective addition of specific modifications to the ascarosides. Through stable isotope feeding experiments, we demonstrate the in vivo activity of the CES-like enzymes and provide direct evidence that the acyl-CoA synthetase ACS-7, which was previously implicated in the attachment of certain modifications to the ascarosides in C. elegans, instead activates the side chains of certain ascarosides for shortening through β-oxidation. Our data provide a key to the combinatorial logic that gives rise to different modified ascarosides, which should greatly facilitate the exploration of the specific biological functions of these pheromones in the worm.
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Affiliation(s)
- Nasser Faghih
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Subhradeep Bhar
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Yue Zhou
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Abdul Rouf Dar
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Kevin Mai
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Laura S Bailey
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Kari B Basso
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
| | - Rebecca A Butcher
- Department of Chemistry, University of Florida, Gainesville, Florida, United States
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11
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Eliáš S, Hurychová J, Toubarro D, Frias J, Kunc M, Dobeš P, Simões N, Hyršl P. Bioactive Excreted/Secreted Products of Entomopathogenic Nematode Heterorhabditis bacteriophora Inhibit the Phenoloxidase Activity during the Infection. INSECTS 2020; 11:insects11060353. [PMID: 32516962 PMCID: PMC7349556 DOI: 10.3390/insects11060353] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/27/2020] [Accepted: 06/03/2020] [Indexed: 12/11/2022]
Abstract
Entomopathogenic nematodes (EPNs) are efficient insect parasites, that are known for their mutualistic relationship with entomopathogenic bacteria and their use in biocontrol. EPNs produce bioactive molecules referred to as excreted/secreted products (ESPs), which have come to the forefront in recent years because of their role in the process of host invasion and the modulation of its immune response. In the present study, we confirmed the production of ESPs in the EPN Heterorhabditis bacteriophora, and investigated their role in the modulation of the phenoloxidase cascade, one of the key components of the insect immune system. ESPs were isolated from 14- and 21-day-old infective juveniles of H. bacteriophora, which were found to be more virulent than newly emerged nematodes, as was confirmed by mortality assays using Galleria mellonella larvae. The isolated ESPs were further purified and screened for the phenoloxidase-inhibiting activity. In these products, a 38 kDa fraction of peptides was identified as the main candidate source of phenoloxidase-inhibiting compounds. This fraction was further analyzed by mass spectrometry and the de novo sequencing approach. Six peptide sequences were identified in this active ESP fraction, including proteins involved in ubiquitination and the regulation of a Toll pathway, for which a role in the regulation of insect immune response has been proposed in previous studies.
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Affiliation(s)
- Sara Eliáš
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic; (S.E.); (J.H.); (M.K.)
| | - Jana Hurychová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic; (S.E.); (J.H.); (M.K.)
| | - Duarte Toubarro
- CBA and Faculty of Sciences and Technology, University of Azores, Rua Mãe de Deus n° 13, 9500-321 Ponta Delgada, Portugal; (D.T.); (J.F.); (N.S.)
| | - Jorge Frias
- CBA and Faculty of Sciences and Technology, University of Azores, Rua Mãe de Deus n° 13, 9500-321 Ponta Delgada, Portugal; (D.T.); (J.F.); (N.S.)
| | - Martin Kunc
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic; (S.E.); (J.H.); (M.K.)
| | - Pavel Dobeš
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic; (S.E.); (J.H.); (M.K.)
- Correspondence: (P.D.); (P.H.); Tel.: +420-549-49-3419 (P.D.); +420-549-49-4510 (P.H.)
| | - Nelson Simões
- CBA and Faculty of Sciences and Technology, University of Azores, Rua Mãe de Deus n° 13, 9500-321 Ponta Delgada, Portugal; (D.T.); (J.F.); (N.S.)
| | - Pavel Hyršl
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic; (S.E.); (J.H.); (M.K.)
- Correspondence: (P.D.); (P.H.); Tel.: +420-549-49-3419 (P.D.); +420-549-49-4510 (P.H.)
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12
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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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13
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Bouagnon AD, Lin L, Srivastava S, Liu CC, Panda O, Schroeder FC, Srinivasan S, Ashrafi K. Intestinal peroxisomal fatty acid β-oxidation regulates neural serotonin signaling through a feedback mechanism. PLoS Biol 2019; 17:e3000242. [PMID: 31805041 PMCID: PMC6917301 DOI: 10.1371/journal.pbio.3000242] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 12/17/2019] [Accepted: 11/15/2019] [Indexed: 02/02/2023] Open
Abstract
The ability to coordinate behavioral responses with metabolic status is fundamental to the maintenance of energy homeostasis. In numerous species including Caenorhabditis elegans and mammals, neural serotonin signaling regulates a range of food-related behaviors. However, the mechanisms that integrate metabolic information with serotonergic circuits are poorly characterized. Here, we identify metabolic, molecular, and cellular components of a circuit that links peripheral metabolic state to serotonin-regulated behaviors in C. elegans. We find that blocking the entry of fatty acyl coenzyme As (CoAs) into peroxisomal β-oxidation in the intestine blunts the effects of neural serotonin signaling on feeding and egg-laying behaviors. Comparative genomics and metabolomics revealed that interfering with intestinal peroxisomal β-oxidation results in a modest global transcriptional change but significant changes to the metabolome, including a large number of changes in ascaroside and phospholipid species, some of which affect feeding behavior. We also identify body cavity neurons and an ether-a-go-go (EAG)-related potassium channel that functions in these neurons as key cellular components of the circuitry linking peripheral metabolic signals to regulation of neural serotonin signaling. These data raise the possibility that the effects of serotonin on satiety may have their origins in feedback, homeostatic metabolic responses from the periphery.
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Affiliation(s)
- Aude D. Bouagnon
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Lin Lin
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Shubhi Srivastava
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Chung-Chih Liu
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Oishika Panda
- Boyce Thompson Institute, Cornell University, Ithaca, New York, United States of America
| | - Frank C. Schroeder
- Boyce Thompson Institute, Cornell University, Ithaca, New York, United States of America
| | - Supriya Srinivasan
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Kaveh Ashrafi
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
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14
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Ascaroside Pheromones: Chemical Biology and Pleiotropic Neuronal Functions. Int J Mol Sci 2019; 20:ijms20163898. [PMID: 31405082 PMCID: PMC6719183 DOI: 10.3390/ijms20163898] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/1970] [Revised: 07/26/2019] [Accepted: 08/07/2019] [Indexed: 12/21/2022] Open
Abstract
Pheromones are neuronal signals that stimulate conspecific individuals to react to environmental stressors or stimuli. Research on the ascaroside (ascr) pheromones in Caenorhabditis elegans and other nematodes has made great progress since ascr#1 was first isolated and biochemically defined in 2005. In this review, we highlight the current research on the structural diversity, biosynthesis, and pleiotropic neuronal functions of ascr pheromones and their implications in animal physiology. Experimental evidence suggests that ascr biosynthesis starts with conjugation of ascarylose to very long-chain fatty acids that are then processed via peroxisomal β-oxidation to yield diverse ascr pheromones. We also discuss the concentration and stage-dependent pleiotropic neuronal functions of ascr pheromones. These functions include dauer induction, lifespan extension, repulsion, aggregation, mating, foraging and detoxification, among others. These roles are carried out in coordination with three G protein-coupled receptors that function as putative pheromone receptors: SRBC-64/66, SRG-36/37, and DAF-37/38. Pheromone sensing is transmitted in sensory neurons via DAF-16-regulated glutamatergic neurotransmitters. Neuronal peroxisomal fatty acid β-oxidation has important cell-autonomous functions in the regulation of neuroendocrine signaling, including neuroprotection. In the future, translation of our knowledge of nematode ascr pheromones to higher animals might be beneficial, as ascr#1 has some anti-inflammatory effects in mice. To this end, we propose the establishment of pheromics (pheromone omics) as a new subset of integrated disciplinary research area within chemical ecology for system-wide investigation of animal pheromones.
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15
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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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16
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Zhou Y, Zhang X, Butcher RA. Tryptophan Metabolism in Caenorhabditis elegans Links Aggregation Behavior to Nutritional Status. ACS Chem Biol 2019; 14:50-57. [PMID: 30586284 DOI: 10.1021/acschembio.8b00872] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Caenorhabditis elegans uses aggregation pheromones to communicate its nutritional status and recruit fellow members of its species to food sources. These aggregation pheromones include the IC-ascarosides, ascarosides modified with an indole-3-carbonyl (IC) group on the 4'-position of the ascarylose sugar. Nothing is known about the biosynthesis of the IC modification beyond the fact that it is derived from tryptophan. Here, we show that C. elegans produces endogenously several indole-containing metabolites, including indole-3-pyruvic acid (IPA), indole-3-acetic acid (IAA; auxin), and indole-3-carboxylic acid, and that these metabolites are intermediates in the biosynthetic pathway from tryptophan to the IC group. Stable isotope-labeled IPA and IAA are incorporated into the IC-ascarosides. Importantly, we show that flux through the biosynthetic pathway is affected by the activity of the pyruvate dehydrogenase complex (PDC). Knockdown of the PDC by RNA interference leads to an accumulation of upstream metabolites and a reduction in downstream metabolites in the pathway. Our results show that production of aggregation pheromones is linked to PDC activity and that aggregation behavior may reflect a favorable metabolic state in the worm. Lastly, we show that treatment of C. elegans with indole-containing metabolites in the pathway induces the biosynthesis of the IC-ascarosides. Because the natural environment of C. elegans is rotting plant material, indole-containing metabolites in this environment could potentially stimulate pheromone biosynthesis and aggregation behavior in the worm. Thus, there may be important links between tryptophan metabolism in C. elegans and in plants and bacteria that enable interkingdom signaling.
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Affiliation(s)
- Yue Zhou
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Xinxing Zhang
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Rebecca A. Butcher
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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17
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McGrath PT, Ruvinsky I. A primer on pheromone signaling in Caenorhabditis elegans for systems biologists. ACTA ACUST UNITED AC 2018; 13:23-30. [PMID: 30984890 DOI: 10.1016/j.coisb.2018.08.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Individuals communicate information about their age, sex, social status, and recent life history with other members of their species through the release of pheromones, chemical signals that elicit behavioral or physiological changes in the recipients. Pheromones provide a fascinating example of information exchange: animals have evolved intraspecific languages in the presence of eavesdroppers and cheaters. In this review, we discuss the recent work using the nematode C. elegans to decipher its chemical language through the analysis of ascaroside pheromones. Genetic dissection has started to identify the enzymes that produce pheromones and the neural circuits that process these signals. Ecological experiments have characterized the biotic environment of C. elegans and its relatives, including ecological relationships with a variety of species that sense or release similar blends of ascarosides. Systems biology approaches should be fruitful in understanding the organization and function of communication systems in C. elegans.
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Affiliation(s)
- Patrick T McGrath
- Department of Biological Sciences, Department of Physics; Georgia Institute of Technology, Atlanta, GA 30332.
| | - Ilya Ruvinsky
- Department of Molecular Biosciences; Northwestern University, Evanston, IL 60208.
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18
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Zhou Y, Wang Y, Zhang X, Bhar S, Jones Lipinski RA, Han J, Feng L, Butcher RA. Biosynthetic tailoring of existing ascaroside pheromones alters their biological function in C. elegans. eLife 2018; 7:33286. [PMID: 29863473 PMCID: PMC5986272 DOI: 10.7554/elife.33286] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 04/26/2018] [Indexed: 11/13/2022] Open
Abstract
Caenorhabditis elegans produces ascaroside pheromones to control its development and behavior. Even minor structural differences in the ascarosides have dramatic consequences for their biological activities. Here, we identify a mechanism that enables C. elegans to dynamically tailor the fatty-acid side chains of the indole-3-carbonyl (IC)-modified ascarosides it has produced. In response to starvation, C. elegans uses the peroxisomal acyl-CoA synthetase ACS-7 to activate the side chains of medium-chain IC-ascarosides for β-oxidation involving the acyl-CoA oxidases ACOX-1.1 and ACOX-3. This pathway rapidly converts a favorable ascaroside pheromone that induces aggregation to an unfavorable one that induces the stress-resistant dauer larval stage. Thus, the pathway allows the worm to respond to changing environmental conditions and alter its chemical message without having to synthesize new ascarosides de novo. We establish a new model for biosynthesis of the IC-ascarosides in which side-chain β-oxidation is critical for controlling the type of IC-ascarosides produced. Small roundworms such as Caenorhabditis elegans release chemical signals called ascarosides in order to communicate with other worms of the same species. Using the ascarosides, the worm can tell its friends, for example, how crowded the neighborhood is and whether there is enough food. The ascarosides thus help the worms in the population decide whether the neighborhood is good – meaning they should hang around, eat, and make babies – or whether the neighborhood is bad. If so, the worms should develop into a larval stage specialized for dispersal that will allow them to find a better neighborhood. Roundworms make the ascarosides by attaching a long chemical ‘side chain’ to an ascarylose sugar. Further chemical modifications allow the worms to produce different signals. In general, to signal a good neighborhood, worms attach a structure called an indole group to the ascarosides. To signal a bad neighborhood, worms make the side chain very short. But how does a worm control which ascarosides it makes? Zhou, Wang et al. now show that C. elegans can change the meaning of its chemical message by modifying the ascarosides that it has already produced instead of making new ones from scratch. Specifically, as their neighborhood runs out of food, C. elegans can use an enzyme called ACS-7 to initiate the shortening of the side chains of indole-ascarosides. The worm can thus change a favorable ascaroside signal that causes the worms to group together into an unfavorable ascaroside signal that causes the worms to enter their dispersal stage. Although Zhou, Wang et al. have focused on chemical communication in C. elegans, the findings could easily apply to the many other species of roundworm that produce ascarosides. Knowing how worms communicate will help us to understand how worms respond to their environment. This knowledge could potentially be used to interfere with the lifecycles and survival of parasitic worm species that harm health and crops.
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Affiliation(s)
- Yue Zhou
- Department of Chemistry, University of Florida, Gainesville, United States
| | - Yuting Wang
- Department of Chemistry, University of Florida, Gainesville, United States
| | - Xinxing Zhang
- Department of Chemistry, University of Florida, Gainesville, United States
| | - Subhradeep Bhar
- Department of Chemistry, University of Florida, Gainesville, United States
| | | | - Jungsoo Han
- Department of Chemistry, University of Florida, Gainesville, United States
| | - Likui Feng
- Department of Chemistry, University of Florida, Gainesville, United States
| | - Rebecca A Butcher
- Department of Chemistry, University of Florida, Gainesville, United States
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