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Zhu M, Chen Y, Cheng L, Li X, Shen Y, Guo G, Xu X, Li H, Yang H, Liu C, He K. Calsyntenin-1 Promotes Doxorubicin-induced Dilated Cardiomyopathy in Rats. Cardiovasc Drugs Ther 2024; 38:237-252. [PMID: 36350487 PMCID: PMC10959838 DOI: 10.1007/s10557-022-07389-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/30/2022] [Indexed: 11/10/2022]
Abstract
PURPOSE Doxorubicin is an important cancer chemotherapeutic agent with severe cardiotoxic effects that eventually lead to dilated cardiomyopathy (DCM). Calsyntenin-1(CLSTN1) plays a critical role in the nervous system, but its relevance in cardiovascular diseases is unknown. We investigated the significance of CLSTN1 in doxorubicin-induced DCM. METHODS CLSTN1 expression in doxorubicin-induced DCM rats and H9c2 cells was determined using western blotting. To further explore the functions of CLSTN1, a cardiac-specific CLSTN1 overexpression rat model was constructed. The rats were subjected to analysis using echocardiographic, hemodynamic, and electrocardiographic parameters. Potential downstream molecules in CLSTN1 overexpression heart tissue were investigated using proteomics and western blotting. Finally, a knockdown of CLSTN1 was constructed to investigate the rescue function on doxorubicin-induced cell toxicity. RESULTS CLSTN1 protein expression increased drastically in doxorubicin-induced DCM rats and H9c2 cells. Under doxorubicin treatment, CLSTN1 protein-specific overexpression in the heart muscle promoted cardiac chamber enlargement and heart failure, while the knockdown of CLSTN1 reduced doxorubicin-induced cardiomyocyte toxicity in vitro. At the mechanistic level, overexpression of CLSTN1 downregulated SERCA2 expression and increased the phosphorylation levels of PI3K-Akt and CaMK2. CONCLUSION Our findings demonstrated that CLSTN1 promotes the pathogenesis of doxorubicin-induced DCM. CLSTN1 could be a therapeutic target to prevent the development of doxorubicin-induced DCM.
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Affiliation(s)
- Mingxiang Zhu
- Medical School of Chinese PLA, Beijing, 100853, China
- Medical Big Data Research Center, Chinese PLA General Hospital, Beijing, 100853, China
| | - Yibing Chen
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Liting Cheng
- Medical School of Chinese PLA, Beijing, 100853, China
- Medical Big Data Research Center, Chinese PLA General Hospital, Beijing, 100853, China
- School of Medicine, Nankai University, Tianjin, 300071, China
| | - Xin Li
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Yanying Shen
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Ge Guo
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Xiang Xu
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Hanlu Li
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China
| | - Hao Yang
- Department of Radiation Oncology, Inner Mongolia Cancer Hospital and Affiliated People's Hospital of Inner Mongolia Medical University, Huhhot, China
| | - Chunlei Liu
- Translational Medicine Research Center, Medical Innovation Research Division of Chinese PLA General Hospital, Beijing, 100853, China.
| | - Kunlun He
- Medical Big Data Research Center, Chinese PLA General Hospital, Beijing, 100853, China.
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2
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Egan BM, Pohl F, Anderson X, Williams SC, Gregory Adodo I, Hunt P, Wang Z, Chiu CH, Scharf A, Mosley M, Kumar S, Schneider DL, Fujiwara H, Hsu FF, Kornfeld K. The ACE inhibitor captopril inhibits ACN-1 to control dauer formation and aging. Development 2024; 151:dev202146. [PMID: 38284547 PMCID: PMC10911126 DOI: 10.1242/dev.202146] [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: 07/17/2023] [Accepted: 01/02/2024] [Indexed: 01/30/2024]
Abstract
The renin-angiotensin-aldosterone system (RAAS) plays a well-characterized role regulating blood pressure in mammals. Pharmacological and genetic manipulation of the RAAS has been shown to extend lifespan in Caenorhabditis elegans, Drosophila and rodents, but its mechanism is not well defined. Here, we investigate the angiotensin-converting enzyme (ACE) inhibitor drug captopril, which extends lifespan in worms and mice. To investigate the mechanism, we performed a forward genetic screen for captopril-hypersensitive mutants. We identified a missense mutation that causes a partial loss of function of the daf-2 receptor tyrosine kinase gene, a powerful regulator of aging. The homologous mutation in the human insulin receptor causes Donohue syndrome, establishing these mutant worms as an invertebrate model of this disease. Captopril functions in C. elegans by inhibiting ACN-1, the worm homolog of ACE. Reducing the activity of acn-1 via captopril or RNA interference promoted dauer larvae formation, suggesting that acn-1 is a daf gene. Captopril-mediated lifespan extension was abrogated by daf-16(lf) and daf-12(lf) mutations. Our results indicate that captopril and acn-1 influence lifespan by modulating dauer formation pathways. We speculate that this represents a conserved mechanism of lifespan control.
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Affiliation(s)
- Brian M. Egan
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Franziska Pohl
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xavier Anderson
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shoshana C. Williams
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | - Patrick Hunt
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zuoxu Wang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chen-Hao Chiu
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Andrea Scharf
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Department of Biological Sciences, Missouri University of Science and Technology, Rolla, MO 65409, USA
| | - Matthew Mosley
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sandeep Kumar
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Daniel L. Schneider
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hideji Fujiwara
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Fong-Fu Hsu
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kerry Kornfeld
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
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3
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Liu CC, Khan A, Seban N, Littlejohn N, Srinivasan S. A homeostatic gut-to-brain insulin antagonist restrains neuronally stimulated fat loss. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.20.563330. [PMID: 37961386 PMCID: PMC10634694 DOI: 10.1101/2023.10.20.563330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
In C. elegans mechanisms by which peripheral organs relay internal state information to the nervous system remain unknown, although strong evidence suggests that such signals do exist. Here we report the discovery of a peptide of the ancestral insulin superfamily called INS-7 that functions as an enteroendocrine peptide and is secreted from specialized cells of the intestine. INS-7 secretion increases during fasting, and acts as a bona fide gut-to-brain homeostatic signal that attenuates neuronally induced fat loss during food shortage. INS-7 functions as an antagonist at the canonical DAF-2 receptor in the nervous system, and phylogenetic analysis suggests that INS-7 bears greater resemblance to members of the broad insulin/relaxin superfamily than to conventional mammalian insulin and IGF peptides. The discovery of an endogenous insulin antagonist secreted by specialized intestinal cell with enteroendocrine functions suggests that much remains to be learned about the intestine and its role in directing neuronal functions.
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4
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Tang LTH, Lee GA, Cook SJ, Ho J, Potter CC, Bülow HE. Anatomical restructuring of a lateralized neural circuit during associative learning by asymmetric insulin signaling. Curr Biol 2023; 33:3835-3850.e6. [PMID: 37591249 PMCID: PMC10639090 DOI: 10.1016/j.cub.2023.07.041] [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: 06/14/2023] [Revised: 07/18/2023] [Accepted: 07/20/2023] [Indexed: 08/19/2023]
Abstract
Studies of neuronal connectivity in model organisms, i.e., of their connectomes, have been instrumental in dissecting the structure-function relationship of nervous systems. However, the limited sample size of these studies has impeded analyses into how variation of connectivity across populations may influence circuit architecture and behavior. Moreover, little is known about how experiences induce changes in circuit architecture. Here, we show that an asymmetric salt-sensing circuit in the nematode Caenorhabditis elegans exhibits variation that predicts the animals' salt preferences and undergoes restructuring during salt associative learning. Naive worms memorize and prefer the salt concentration they experience in the presence of food through a left-biased neural network architecture. However, animals conditioned at elevated salt concentrations change this left-biased network to a right-biased network. This change in circuit architecture occurs through the addition of new synapses in response to asymmetric, paracrine insulin signaling. Therefore, experience-dependent changes in an animal's neural connectome are induced by insulin signaling and are fundamental to learning and behavior.
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Affiliation(s)
- Leo T H Tang
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Garrett A Lee
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Steven J Cook
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jacquelin Ho
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Cassandra C Potter
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Hannes E Bülow
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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5
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Egan BM, Pohl F, Anderson X, Williams SC, Adodo IG, Hunt P, Wang Z, Chiu CH, Scharf A, Mosley M, Kumar S, Schneider DL, Fujiwara H, Hsu FF, Kornfeld K. The ACE-inhibitor drug captopril inhibits ACN-1 to control dauer formation and aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.17.549402. [PMID: 37502959 PMCID: PMC10370070 DOI: 10.1101/2023.07.17.549402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The renin-angiotensin-aldosterone system (RAAS) plays a well-characterized role regulating blood pressure in mammals. Pharmacological and genetic manipulation of the RAAS has been shown to extend lifespan in C. elegans , Drosophila , and rodents, but its mechanism is not well defined. Here we investigate the angiotensin-converting enzyme (ACE) inhibitor drug captopril, which extends lifespan in worms and mice. To investigate the mechanism, we performed a forward genetic screen for captopril hypersensitive mutants. We identified a missense mutation that causes a partial loss-of-function of the daf-2 receptor tyrosine kinase gene, a powerful regulator of aging. The homologous mutation in the human insulin receptor causes Donohue syndrome, establishing these mutant worms as an invertebrate model of this disease. Captopril functions in C. elegans by inhibiting ACN-1, the worm homolog of ACE. Reducing the activity of acn-1 via captopril or RNAi promoted dauer larvae formation, suggesting acn-1 is a daf gene. Captopril-mediated lifespan extension xwas abrogated by daf-16(lf) and daf-12(lf) mutations. Our results indicate that captopril and acn-1 control aging by modulating dauer formation pathways. We speculate that this represents a conserved mechanism of lifespan control. Summary Statement Captopril and acn-1 control aging. By demonstrating they regulate dauer formation and interact with daf genes, including a new DAF-2(A261V) mutant corresponding to a human disease variant, we clarified the mechanism.
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6
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Deng S, Yi P, Xu M, Yi Q, Feng J. Dysfunctional gene splicing in glucose metabolism may contribute to Alzheimer's disease. Chin Med J (Engl) 2023; 136:666-675. [PMID: 35830275 PMCID: PMC10129079 DOI: 10.1097/cm9.0000000000002214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Indexed: 11/26/2022] Open
Abstract
ABSTRACT The glucose metabolism is crucial for sustained brain activity as it provides energy and is a carbon source for multiple biomacromolecules; glucose metabolism decreases dramatically in Alzheimer's disease (AD) and may be a fundamental cause for its development. Recent studies reveal that the alternative splicing events of certain genes effectively regulate several processes in glucose metabolism including insulin receptor, insulin-degrading enzyme, pyruvate kinase M, receptor for advanced glycation endproducts, and others, thereby, influencing glucose uptake, glycolysis, and advanced glycation end-products-mediated signaling pathways. Indeed, the discovery of aberrant alternative splicing that changes the proteomic diversity and protein activity in glucose metabolism has been pivotal in our understanding of AD development. In this review, we summarize the alternative splicing events of the glucose metabolism-related genes in AD pathology and highlight the crucial regulatory roles of splicing factors in the alternative splicing process. We also discuss the emerging therapeutic approaches for targeting splicing factors for AD treatment.
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Affiliation(s)
- Shengfeng Deng
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Peng Yi
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Mingliang Xu
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Qian Yi
- Department of Physiology, School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Jianguo Feng
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
- Affiliated Xinhui Hospital, Southern Medical University (People's Hospital of Xinhui District), Jiangmen, Guangdong 529100, China
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7
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Tang LTH, Lee GA, Cook SJ, Ho J, Potter CC, Bülow HE. Restructuring of an asymmetric neural circuit during associative learning. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.12.523604. [PMID: 36711870 PMCID: PMC9882173 DOI: 10.1101/2023.01.12.523604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Asymmetric brain function is common across the animal kingdom and involved in language processing, and likely in learning and memory. What regulates asymmetric brain function remains elusive. Here, we show that the nematode Caenorhabditis elegans restructures an asymmetric salt sensing neural circuit during associative learning. Worms memorize and prefer the salt concentration at which they were raised in the presence of food through a left-biased network architecture. When conditioned at elevated salt concentrations, animals change the left-biased to a right-biased network, which explains the changed salt-seeking behavior. The changes in circuit architecture require new synapse formation induced through asymmetric, paracrine insulin-signaling. Therefore, experience-dependent changes in asymmetric network architecture rely on paracrine insulin signaling and are fundamental to learning and behavior.
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8
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Cheng D, Lee JS, Brown M, Ebert MS, McGrath PT, Tomioka M, Iino Y, Bargmann CI. Insulin/IGF signaling regulates presynaptic glutamate release in aversive olfactory learning. Cell Rep 2022; 41:111685. [DOI: 10.1016/j.celrep.2022.111685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 08/06/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022] Open
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9
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Roy C, Molin L, Alcolei A, Solyga M, Bonneau B, Vachon C, Bessereau JL, Solari F. DAF-2/insulin IGF-1 receptor regulates motility during aging by integrating opposite signaling from muscle and neuronal tissues. Aging Cell 2022; 21:e13660. [PMID: 35808897 PMCID: PMC9381905 DOI: 10.1111/acel.13660] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 05/27/2022] [Accepted: 06/05/2022] [Indexed: 12/11/2022] Open
Abstract
During aging, preservation of locomotion is generally considered an indicator of sustained good health, in elderlies and in animal models. In Caenorhabditis elegans, mutants of the insulin‐IGF‐1 receptor DAF2/IIRc represent a paradigm of healthy aging, as their increased lifespan is accompanied by a delay in age‐related loss of motility. Here, we investigated the DAF‐2/IIRc‐dependent relationship between longevity and motility using an auxin‐inducible degron to trigger tissue‐specific degradation of endogenous DAF‐2/IIRc. As previously reported, inactivation of DAF‐2/IIRc in neurons or intestine was sufficient to extend the lifespan of worms, whereas depletion in epidermis, germline, or muscle was not. However, neither intestinal nor neuronal depletion of DAF‐2/IIRc prevented the age‐related loss of motility. In 1‐day‐old adults, DAF‐2/IIRc depletion in neurons reduced motility in a DAF‐16/FOXO dependent manner, while muscle depletion had no effect. By contrast, DAF‐2 depletion in the muscle of middle‐age animals improved their motility independently of DAF‐16/FOXO but required UNC‐120/SRF. Yet, neuronal or muscle DAF‐2/IIRc depletion both preserved the mitochondria network in aging muscle. Overall, these results show that the motility pattern of daf‐2 mutants is determined by the sequential and opposing impact of neurons and muscle tissues and can be dissociated from the regulation of the lifespan. This work also provides the characterization of a versatile tool to analyze the tissue‐specific contribution of insulin‐like signaling in integrated phenotypes at the whole organism level.
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Affiliation(s)
- Charline Roy
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Laurent Molin
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Allan Alcolei
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Mathilde Solyga
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Benjamin Bonneau
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Camille Vachon
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Jean-Louis Bessereau
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
| | - Florence Solari
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS UMR5284, INSERMU1314, Institut NeuroMyoGène, MeLis, Lyon, France
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10
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Khan M, Hartmann AH, O’Donnell MP, Piccione M, Pandey A, Chao PH, Dwyer ND, Bargmann CI, Sengupta P. Context-dependent reversal of odorant preference is driven by inversion of the response in a single sensory neuron type. PLoS Biol 2022; 20:e3001677. [PMID: 35696430 PMCID: PMC9232122 DOI: 10.1371/journal.pbio.3001677] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 06/24/2022] [Accepted: 05/16/2022] [Indexed: 11/18/2022] Open
Abstract
The valence and salience of individual odorants are modulated by an animal’s innate preferences, learned associations, and internal state, as well as by the context of odorant presentation. The mechanisms underlying context-dependent flexibility in odor valence are not fully understood. Here, we show that the behavioral response of Caenorhabditis elegans to bacterially produced medium-chain alcohols switches from attraction to avoidance when presented in the background of a subset of additional attractive chemicals. This context-dependent reversal of odorant preference is driven by cell-autonomous inversion of the response to these alcohols in the single AWC olfactory neuron pair. We find that while medium-chain alcohols inhibit the AWC olfactory neurons to drive attraction, these alcohols instead activate AWC to promote avoidance when presented in the background of a second AWC-sensed odorant. We show that these opposing responses are driven via engagement of distinct odorant-directed signal transduction pathways within AWC. Our results indicate that context-dependent recruitment of alternative intracellular signaling pathways within a single sensory neuron type conveys opposite hedonic valences, thereby providing a robust mechanism for odorant encoding and discrimination at the periphery.
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Affiliation(s)
- Munzareen Khan
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Anna H. Hartmann
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Michael P. O’Donnell
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Madeline Piccione
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Anjali Pandey
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Pin-Hao Chao
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
| | - Noelle D. Dwyer
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | | | - Piali Sengupta
- Department of Biology, Brandeis University, Waltham, Massachusetts, United States of America
- * E-mail:
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11
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Invited review: Unearthing the mechanisms of age-related neurodegenerative disease using Caenorhabditis elegans. Comp Biochem Physiol A Mol Integr Physiol 2022; 267:111166. [PMID: 35176489 DOI: 10.1016/j.cbpa.2022.111166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 12/11/2022]
Abstract
As human life expectancy increases, neurodegenerative diseases present a growing public health threat, for which there are currently few effective treatments. There is an urgent need to understand the molecular and genetic underpinnings of these disorders so new therapeutic targets can be identified. Here we present the argument that the simple nematode worm Caenorhabditis elegans is a powerful tool to rapidly study neurodegenerative disorders due to their short lifespan and vast array of genetic tools, which can be combined with characterization of conserved neuronal processes and behavior orthologous to those disrupted in human disease. We review how pre-existing C. elegans models provide insight into human neurological disease as well as an overview of current tools available to study neurodegenerative diseases in the worm, with an emphasis on genetics and behavior. We also discuss open questions that C. elegans may be particularly well suited for in future studies and how worms will be a valuable preclinical model to better understand these devastating neurological disorders.
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12
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Nakai J, Chikamoto N, Fujimoto K, Totani Y, Hatakeyama D, Dyakonova VE, Ito E. Insulin and Memory in Invertebrates. Front Behav Neurosci 2022; 16:882932. [PMID: 35558436 PMCID: PMC9087806 DOI: 10.3389/fnbeh.2022.882932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 04/04/2022] [Indexed: 11/17/2022] Open
Abstract
Insulin and insulin-like peptides (ILP) help to maintain glucose homeostasis, whereas insulin-like growth factor (IGF) promotes the growth and differentiation of cells in both vertebrates and invertebrates. It is sometimes difficult to distinguish between ILP and IGF in invertebrates, however, because in some cases ILP has the same function as IGF. In the present review, therefore, we refer to these peptides as ILP/IGF signaling (IIS) in invertebrates, and discuss the role of IIS in memory formation after classical conditioning in invertebrates. In the arthropod Drosophila melanogaster, IIS is involved in aversive olfactory memory, and in the nematode Caenorhabditis elegans, IIS controls appetitive/aversive response to NaCl depending on the duration of starvation. In the mollusk Lymnaea stagnalis, IIS has a critical role in conditioned taste aversion. Insulin in mammals is also known to play an important role in cognitive function, and many studies in humans have focused on insulin as a potential treatment for Alzheimer’s disease. Although analyses of tissue and cellular levels have progressed in mammals, the molecular mechanisms, such as transcriptional and translational levels, of IIS function in cognition have been far advanced in studies using invertebrates. We anticipate that the present review will help to pave the way for studying the effects of insulin, ILPs, and IGFs in cognitive function across phyla.
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Affiliation(s)
- Junko Nakai
- Department of Biology, Waseda University, Tokyo, Japan
| | | | | | - Yuki Totani
- Department of Biology, Waseda University, Tokyo, Japan
| | - Dai Hatakeyama
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Varvara E. Dyakonova
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Etsuro Ito
- Department of Biology, Waseda University, Tokyo, Japan
- Graduate Institute of Medicine, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- *Correspondence: Etsuro Ito
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13
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Liu Z, Jiang M, Liakath-Ali K, Sclip A, Ko J, Zhang RS, Südhof TC. Deletion of Calsyntenin-3, an atypical cadherin, suppresses inhibitory synapses but increases excitatory parallel-fiber synapses in cerebellum. eLife 2022; 11:e70664. [PMID: 35420982 PMCID: PMC9064300 DOI: 10.7554/elife.70664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 04/14/2022] [Indexed: 01/11/2023] Open
Abstract
Cadherins contribute to the organization of nearly all tissues, but the functions of several evolutionarily conserved cadherins, including those of calsyntenins, remain enigmatic. Puzzlingly, two distinct, non-overlapping functions for calsyntenins were proposed: As postsynaptic neurexin ligands in synapse formation, or as presynaptic kinesin adaptors in vesicular transport. Here, we show that, surprisingly, acute CRISPR-mediated deletion of calsyntenin-3 in mouse cerebellum in vivo causes a large decrease in inhibitory synapse, but a robust increase in excitatory parallel-fiber synapses in Purkinje cells. As a result, inhibitory synaptic transmission was suppressed, whereas parallel-fiber synaptic transmission was enhanced in Purkinje cells by the calsyntenin-3 deletion. No changes in the dendritic architecture of Purkinje cells or in climbing-fiber synapses were detected. Sparse selective deletion of calsyntenin-3 only in Purkinje cells recapitulated the synaptic phenotype, indicating that calsyntenin-3 acts by a cell-autonomous postsynaptic mechanism in cerebellum. Thus, by inhibiting formation of excitatory parallel-fiber synapses and promoting formation of inhibitory synapses in the same neuron, calsyntenin-3 functions as a postsynaptic adhesion molecule that regulates the excitatory/inhibitory balance in Purkinje cells.
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Affiliation(s)
- Zhihui Liu
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
- Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Man Jiang
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
| | - Kif Liakath-Ali
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
| | - Alessandra Sclip
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
- Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Jaewon Ko
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and TechnologyDaeguRepublic of Korea
| | - Roger Shen Zhang
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Stanford UniversityStanfordUnited States
- Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
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14
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Sheardown E, Mech AM, Petrazzini MEM, Leggieri A, Gidziela A, Hosseinian S, Sealy IM, Torres-Perez JV, Busch-Nentwich EM, Malanchini M, Brennan CH. Translational relevance of forward genetic screens in animal models for the study of psychiatric disease. Neurosci Biobehav Rev 2022; 135:104559. [PMID: 35124155 PMCID: PMC9016269 DOI: 10.1016/j.neubiorev.2022.104559] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 12/10/2021] [Accepted: 02/01/2022] [Indexed: 12/16/2022]
Abstract
Psychiatric disorders represent a significant burden in our societies. Despite the convincing evidence pointing at gene and gene-environment interaction contributions, the role of genetics in the etiology of psychiatric disease is still poorly understood. Forward genetic screens in animal models have helped elucidate causal links. Here we discuss the application of mutagenesis-based forward genetic approaches in common animal model species: two invertebrates, nematodes (Caenorhabditis elegans) and fruit flies (Drosophila sp.); and two vertebrates, zebrafish (Danio rerio) and mice (Mus musculus), in relation to psychiatric disease. We also discuss the use of large scale genomic studies in human populations. Despite the advances using data from human populations, animal models coupled with next-generation sequencing strategies are still needed. Although with its own limitations, zebrafish possess characteristics that make them especially well-suited to forward genetic studies exploring the etiology of psychiatric disorders.
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Affiliation(s)
- Eva Sheardown
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Aleksandra M Mech
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | | | - Adele Leggieri
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Agnieszka Gidziela
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Saeedeh Hosseinian
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Ian M Sealy
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, UK
| | - Jose V Torres-Perez
- UK Dementia Research Institute at Imperial College London and Department of Brain Sciences, Imperial College London, 86 Wood Lane, London W12 0BZ, UK
| | - Elisabeth M Busch-Nentwich
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Margherita Malanchini
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK
| | - Caroline H Brennan
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, England, UK.
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15
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Ohno H, Bao Z. Small RNAs couple embryonic developmental programs to gut microbes. SCIENCE ADVANCES 2022; 8:eabl7663. [PMID: 35319987 PMCID: PMC8942359 DOI: 10.1126/sciadv.abl7663] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Embryogenesis has long been known for its robustness to environmental factors. Although developmental tuning of embryogenesis to the environment experienced by the parent may be beneficial, little is understood on whether and how developmental patterns proactively change. Here, we show that Caenorhabditis elegans undergoes alternative embryogenesis in response to maternal gut microbes. Harmful microbes result in altered endodermal cell divisions; morphological changes, including left-right asymmetric development; double association between intestinal and primordial germ cells; and partial rescue of fecundity. The miR-35 microRNA family, which is controlled by systemic endogenous RNA interference and targets the β-transducin repeat-containing protein/cell division cycle 25 (CDC25) pathway, transmits intergenerational information to regulate cell divisions and reproduction. Our findings challenge the widespread assumption that C. elegans has an invariant cell lineage that consists of a fixed cell number and provide insights into how organisms optimize embryogenesis to adapt to environmental changes through epigenetic control.
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16
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Del Moro L, Rota E, Pirovano E, Rainero I. Migraine, Brain Glucose Metabolism and the "Neuroenergetic" Hypothesis: A Scoping Review. THE JOURNAL OF PAIN 2022; 23:1294-1317. [PMID: 35296423 DOI: 10.1016/j.jpain.2022.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 02/04/2022] [Accepted: 02/14/2022] [Indexed: 02/06/2023]
Abstract
Increasing evidence suggests that migraine may be the result of an impaired brain glucose metabolism. Several studies have reported brain mitochondrial dysfunction, impaired brain glucose metabolism and gray matter volume reduction in specific brain areas of migraineurs. Furthermore, peripheral insulin resistance, a condition demonstrated in several studies, may extend to the brain, leading to brain insulin resistance. This condition has been proven to downregulate insulin receptors, both in astrocytes and neurons, triggering a reduction in glucose uptake and glycogen synthesis, mainly during high metabolic demand. This scoping review examines the clinical, epidemiologic and pathophysiologic data supporting the hypothesis that abnormalities in brain glucose metabolism may generate a mismatch between the brain's energy reserve and metabolic expenditure, triggering migraine attacks. Moreover, alteration in glucose homeostasis could generate a chronic brain energy deficit promoting migraine chronification. Lastly, insulin resistance may link migraine with its comorbidities, like obesity, depression, cognitive impairment and cerebrovascular diseases. PERSPECTIVE: Although additional experimental studies are needed to support this novel "neuroenergetic" hypothesis, brain insulin resistance in migraineurs may unravel the pathophysiological mechanisms of the disease, explaining the migraine chronification and connecting migraine with comorbidities. Therefore, this hypothesis could elucidate novel potential approaches for migraine treatment.
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Affiliation(s)
- Lorenzo Del Moro
- Foundation Allineare Sanità and Salute, Scientific Committee, Milan, Italy; LUMEN APS, European Salus Network, Scientific Committee, San Pietro in Cerro (PC), Italy.
| | - Eugenia Rota
- Neurology Unit, ASL AL, San Giacomo Hospital, Novi Ligure, Italy
| | - Elenamaria Pirovano
- Foundation Allineare Sanità and Salute, Scientific Committee, Milan, Italy; LUMEN APS, European Salus Network, Scientific Committee, San Pietro in Cerro (PC), Italy
| | - Innocenzo Rainero
- Headache Center, Department of Neuroscience "Rita Levi Montalcini", University of Torino, Italy
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17
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Mori K, Koebis M, Nakao K, Kobayashi S, Kiyama Y, Watanabe M, Manabe T, Iino Y, Aiba A. Loss of calsyntenin paralogs disrupts interneuron stability and mouse behavior. Mol Brain 2022; 15:23. [PMID: 35279170 PMCID: PMC8917637 DOI: 10.1186/s13041-022-00909-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/02/2022] [Indexed: 11/26/2022] Open
Abstract
Calsyntenins (CLSTNs) are important synaptic molecules whose molecular functions are not fully understood. Although mutations in calsyntenin (CLSTN) genes have been associated with psychiatric disorders in humans, their function is still unclear. One of the reasons why the function of CLSTNs in the nervous system has not been clarified is the functional redundancy among the three paralogs. Therefore, to investigate the functions of mammalian CLSTNs, we generated triple knockout (TKO) mice lacking all CLSTN paralogs and examined their behavior. The mutant mice tended to freeze in novel environments and exhibited hypersensitivity to stress. Consistent with this, glucose levels under stress were significantly higher in the mutant mice than in the wild-type controls. In particular, phenotypes such as decreased motivation, which had not been reported in single Clstn KO mice, were newly discovered. The TKO mice generated in this study represent an important mouse model for clarifying the function of CLSTN in the future.
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18
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Ike Y, Tomioka M, Iino Y. Involvement of HECT-type E3 ubiquitin ligase genes in salt chemotaxis learning in Caenorhabditis elegans. Genetics 2022; 220:6530289. [PMID: 35176147 PMCID: PMC8982016 DOI: 10.1093/genetics/iyac025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 01/27/2022] [Indexed: 11/14/2022] Open
Abstract
The ubiquitin-proteasome system is associated with various phenomena including learning and memory. In this study, we report that E3 ubiquitin ligase homologs and proteasome function are involved in taste avoidance learning, a type of associative learning between starvation and salt concentrations, in Caenorhabditis elegans. Pharmacological inhibition of proteasome function using bortezomib causes severe defects in taste avoidance learning. Among 9 HECT-type ubiquitin ligase genes, loss-of-function mutations of 6 ubiquitin ligase genes cause significant abnormalities in taste avoidance learning. Double mutations of those genes cause lethality or enhanced defects in taste avoidance learning, suggesting that the HECT-type ubiquitin ligases act in multiple pathways in the processes of learning. Furthermore, mutations of the ubiquitin ligase genes cause additive effects on taste avoidance learning defects of the insulin-like signaling mutants. Our findings unveil the consequences of aberrant functions of the proteasome and ubiquitin systems in learning behavior of Caenorhabditis elegans.
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Affiliation(s)
- Yasuaki Ike
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan
| | - Masahiro Tomioka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan,Corresponding author: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Faculty of Science Building#3, Room 224, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan. ; Corresponding author: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Faculty of Science Building#3, Room 224, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
| | - Yuichi Iino
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan,Corresponding author: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Faculty of Science Building#3, Room 224, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan. ; Corresponding author: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Faculty of Science Building#3, Room 224, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
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19
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Tomioka M, Jang MS, Iino Y. DAF-2c signaling promotes taste avoidance after starvation in Caenorhabditis elegans by controlling distinct phospholipase C isozymes. Commun Biol 2022; 5:30. [PMID: 35017611 PMCID: PMC8752840 DOI: 10.1038/s42003-021-02956-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 12/09/2021] [Indexed: 12/19/2022] Open
Abstract
Previously, we reported that DAF-2c, an axonal insulin receptor isoform in Caenorhabditis elegans, acts in the ASER gustatory neuron to regulate taste avoidance learning, a process in which worms learn to avoid salt concentrations experienced during starvation. Here, we show that secretion of INS-1, an insulin-like peptide, after starvation conditioning is sufficient to drive taste avoidance via DAF-2c signaling. Starvation conditioning enhances the salt-triggered activity of AIA neurons, the main sites of INS-1 release, which potentially promotes feedback signaling to ASER to maintain DAF-2c activity during taste avoidance. Genetic studies suggest that DAF-2c-Akt signaling promotes high-salt avoidance via a decrease in PLCβ activity. On the other hand, the DAF-2c pathway promotes low-salt avoidance via PLCε and putative Akt phosphorylation sites on PLCε are essential for taste avoidance. Our findings imply that animals disperse from the location at which they experience starvation by controlling distinct PLC isozymes via DAF-2c.
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Affiliation(s)
- Masahiro Tomioka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Moon Sun Jang
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Aichi, 464-8602, Japan
| | - Yuichi Iino
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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20
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Pradhan S, Hendricks M. Observing and Quantifying Fluorescent Reporters. Methods Mol Biol 2022; 2468:73-87. [PMID: 35320561 DOI: 10.1007/978-1-0716-2181-3_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Genetically encoded fluorescent reporters take advantage of C. elegans' transparency to allow non-invasive, in vivo observation, and recording of physiological processes in intact animals. Here, we discuss the basic microscope components required to observe, image, and measure fluorescent proteins in live animals for students and researchers who work with C. elegans but have limited experience with fluorescence imaging and analysis.
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Affiliation(s)
- Sreeparna Pradhan
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
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21
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Ding C, Wu Y, Dabas H, Hammarlund M. Activation of the CaMKII-Sarm1-ASK1-p38 MAP kinase pathway protects against axon degeneration caused by loss of mitochondria. eLife 2022; 11:73557. [PMID: 35285800 PMCID: PMC8920508 DOI: 10.7554/elife.73557] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 01/25/2022] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial defects are tightly linked to axon degeneration, yet the underlying cellular mechanisms remain poorly understood. In Caenorhabditis elegans, PVQ axons that lack mitochondria degenerate spontaneously with age. Using an unbiased genetic screen, we found that cell-specific activation of CaMKII/UNC-43 suppresses axon degeneration due to loss of mitochondria. Unexpectedly, CaMKII/UNC-43 activates the conserved Sarm1/TIR-1-ASK1/NSY-1-p38 MAPK pathway and eventually the transcription factor CEBP-1 to protect against degeneration. In addition, we show that disrupting a trafficking complex composed of calsyntenin/CASY-1, Mint/LIN-10, and kinesin suppresses axon degeneration. Further analysis indicates that disruption of this trafficking complex activates the CaMKII-Sarm1-MAPK pathway through L-type voltage-gated calcium channels. Our findings identify CaMKII as a pivot point between mitochondrial defects and axon degeneration, describe how it is regulated, and uncover a surprising neuroprotective role for the Sarm1-p38 MAPK pathway in this context.
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Affiliation(s)
- Chen Ding
- Department of Neuroscience, Yale University School of MedicineNew HavenUnited States
| | - Youjun Wu
- Department of Genetics, Yale University School of MedicineNew HavenUnited States
| | - Hadas Dabas
- Department of Genetics, Yale University School of MedicineNew HavenUnited States
| | - Marc Hammarlund
- Department of Neuroscience, Yale University School of MedicineNew HavenUnited States,Department of Genetics, Yale University School of MedicineNew HavenUnited States
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22
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Cheng H, Liu Y, Xue Y, Shao J, Tan Z, Liu S, Duan S, Kang L. Molecular Strategies for Intensity-Dependent Olfactory Processing in Caenorhabditis elegans. Front Mol Neurosci 2021; 14:748214. [PMID: 34803606 PMCID: PMC8600271 DOI: 10.3389/fnmol.2021.748214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/02/2021] [Indexed: 11/13/2022] Open
Abstract
Various odorants trigger complex animal behaviors across species in both quality- and quantity-dependent manners. However, how the intensity of olfactory input is encoded remains largely unknown. Here we report that isoamyl alcohol (IAA) induces bi-directional currents through a Gα- guanylate cyclase (GC)- cGMP signaling pathway in Caenorhabditis elegans olfactory neuron amphid wing “C” cell (AWC), while two opposite cGMP signaling pathways are responsible for odor-sensing in olfactory neuron amphid wing “B” cell (AWB): (1) a depolarizing Gα (GPA-3)- phosphodiesterase (PDE) – cGMP pathway which can be activated by low concentrations of isoamyl alcohol (IAA), and (2) a hyperpolarizing Gα (ODR-3)- GC- cGMP pathway sensing high concentrations of IAA. Besides, IAA induces Gα (ODR-3)-TRPV(OSM-9)-dependent currents in amphid wing “A” cell (AWA) and amphid neuron “H” cell with single ciliated sensory ending (ASH) neurons with different thresholds. Our results demonstrate that an elaborate combination of multiple signaling machineries encode the intensity of olfactory input, shedding light on understanding the molecular strategies on sensory transduction.
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Affiliation(s)
- Hankui Cheng
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Yu Liu
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Yadan Xue
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiajie Shao
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhibing Tan
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Siyan Liu
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Shumin Duan
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.,Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lijun Kang
- Department of Neurobiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
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23
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Biglou SG, Bendena WG, Chin-Sang I. An overview of the insulin signaling pathway in model organisms Drosophila melanogaster and Caenorhabditis elegans. Peptides 2021; 145:170640. [PMID: 34450203 DOI: 10.1016/j.peptides.2021.170640] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 08/01/2021] [Accepted: 08/20/2021] [Indexed: 12/12/2022]
Abstract
The insulin/insulin-like growth factor signaling pathway is an evolutionary conserved pathway across metazoans and is required for development, metabolism and behavior. This pathway is associated with various human metabolic disorders and cancers. Thus, model organisms including Drosophila melanogaster and Caenorhabditis elegans provide excellent opportunities to examine the structure and function of this pathway and its influence on cellular metabolism and proliferation. In this review, we will provide an overview of human insulin and the human insulin signaling pathway and explore the recent discoveries in model organisms Drosophila melanogaster and Caenorhabditis elegans. Our review will provide information regarding the various insulin-like peptides in model organisms as well as the conserved functions of insulin signaling pathways. Further investigation of the insulin signaling pathway in model organisms could provide a promising opportunity to develop novel therapies for various metabolic disorders and insulin-mediated cancers.
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Affiliation(s)
- Sanaz G Biglou
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada
| | - William G Bendena
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada; Centre for Neuroscience, Queen's University, Kingston, ON, K7L3N6, Canada.
| | - Ian Chin-Sang
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada
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24
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Park HEH, Hwang W, Ham S, Kim E, Altintas O, Park S, Son HG, Lee Y, Lee D, Heo WD, Lee SJV. A PTEN variant uncouples longevity from impaired fitness in Caenorhabditis elegans with reduced insulin/IGF-1 signaling. Nat Commun 2021; 12:5631. [PMID: 34561453 PMCID: PMC8463539 DOI: 10.1038/s41467-021-25920-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 08/24/2021] [Indexed: 01/04/2023] Open
Abstract
Insulin/IGF-1 signaling (IIS) regulates various physiological aspects in numerous species. In Caenorhabditis elegans, mutations in the daf-2/insulin/IGF-1 receptor dramatically increase lifespan and immunity, but generally impair motility, growth, and reproduction. Whether these pleiotropic effects can be dissociated at a specific step in insulin/IGF-1 signaling pathway remains unknown. Through performing a mutagenesis screen, we identified a missense mutation daf-18(yh1) that alters a cysteine to tyrosine in DAF-18/PTEN phosphatase, which maintained the long lifespan and enhanced immunity, while improving the reduced motility in adult daf-2 mutants. We showed that the daf-18(yh1) mutation decreased the lipid phosphatase activity of DAF-18/PTEN, while retaining a partial protein tyrosine phosphatase activity. We found that daf-18(yh1) maintained the partial activity of DAF-16/FOXO but restricted the detrimental upregulation of SKN-1/NRF2, contributing to beneficial physiological traits in daf-2 mutants. Our work provides important insights into how one evolutionarily conserved component, PTEN, can coordinate animal health and longevity.
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Affiliation(s)
- Hae-Eun H Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Wooseon Hwang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, South Korea
| | - Seokjin Ham
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Eunah Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Ozlem Altintas
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, 37673, South Korea
| | - Sangsoon Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Heehwa G Son
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Yujin Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Dongyeop Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, South Korea
| | - Won Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea
| | - Seung-Jae V Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea.
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25
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Rahmani A, Chew YL. Investigating the molecular mechanisms of learning and memory using Caenorhabditis elegans. J Neurochem 2021; 159:417-451. [PMID: 34528252 DOI: 10.1111/jnc.15510] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 08/15/2021] [Accepted: 09/08/2021] [Indexed: 11/30/2022]
Abstract
Learning is an essential biological process for survival since it facilitates behavioural plasticity in response to environmental changes. This process is mediated by a wide variety of genes, mostly expressed in the nervous system. Many studies have extensively explored the molecular and cellular mechanisms underlying learning and memory. This review will focus on the advances gained through the study of the nematode Caenorhabditis elegans. C. elegans provides an excellent system to study learning because of its genetic tractability, in addition to its invariant, compact nervous system (~300 neurons) that is well-characterised at the structural level. Importantly, despite its compact nature, the nematode nervous system possesses a high level of conservation with mammalian systems. These features allow the study of genes within specific sensory-, inter- and motor neurons, facilitating the interrogation of signalling pathways that mediate learning via defined neural circuits. This review will detail how learning and memory can be studied in C. elegans through behavioural paradigms that target distinct sensory modalities. We will also summarise recent studies describing mechanisms through which key molecular and cellular pathways are proposed to affect associative and non-associative forms of learning.
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Affiliation(s)
- Aelon Rahmani
- Flinders Health and Medical Research Institute, Flinders University, Adelaide, South Australia, Australia
| | - Yee Lian Chew
- Flinders Health and Medical Research Institute, Flinders University, Adelaide, South Australia, Australia
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26
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Nakura T, Ozoe A, Narita Y, Matsuo M, Hakuno F, Kataoka N, Takahashi SI. Rbfox2 mediates exon 11 inclusion in insulin receptor pre-mRNA splicing in hepatoma cells. Biochimie 2021; 187:25-32. [PMID: 34022289 DOI: 10.1016/j.biochi.2021.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/10/2021] [Accepted: 05/14/2021] [Indexed: 11/27/2022]
Abstract
Insulin receptor (IR) pre-mRNA undergoes alternative splicing that produces two isoforms, IR-A and IR-B. The ratio of IR-A to IR-B varies among tissues, which strongly suggests that IR mRNA alternative splicing is regulated in a tissue-specific manner. However, the precise molecular mechanism for IR alternative splicing remains to be elucidated, especially in liver. In this study, we have analyzed IR alternative splicing mechanism by preparing a mini-gene splicing reporter with rat genomic DNA. The splicing reporter that contains exon 11 and its flanking intronic sequences could reproduce alternative splicing pattern in rat hepatoma H4IIE cells. Introducing several deletions in introns of the reporter revealed that intron 11 contains the region near exon 11 essential to promote exon 11 inclusion. This region contains an UGCAUG sequence, a specific binding site for the Rbfox splicing regulator, and mutation in this sequence results in exon 11 skipping. Furthermore, RbFox2 knockdown in H4IIE cells enhanced exon 11 skipping of endogenous IR pre-mRNA. Lastly mutations in the SRSF3 binding site of exon11 together with the Rbfox2 binding site completely abolished exon 11 inclusion with a mini-gene reporter pre-mRNA. Our results indicate that RbFox2 and SRSF3 proteins mediate exon 11 inclusion in rat hepatoma cells.
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Affiliation(s)
- Takahito Nakura
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Atsufumi Ozoe
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuka Narita
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Masafumi Matsuo
- KNC Department of Nucleic Acid Drug Discovery, Faculty of Rehabilitation, Kobe Gakuin University, Kobe, Japan
| | - Fumihiko Hakuno
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Naoyuki Kataoka
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan; Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Japan.
| | - Shin-Ichiro Takahashi
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
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27
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Park C, Sakurai Y, Sato H, Kanda S, Iino Y, Kunitomo H. Roles of the ClC chloride channel CLH-1 in food-associated salt chemotaxis behavior of C. elegans. eLife 2021; 10:e55701. [PMID: 33492228 PMCID: PMC7834019 DOI: 10.7554/elife.55701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 01/04/2021] [Indexed: 01/19/2023] Open
Abstract
The ability of animals to process dynamic sensory information facilitates foraging in an ever-changing environment. However, molecular and neural mechanisms underlying such ability remain elusive. The ClC anion channels/transporters play a pivotal role in cellular ion homeostasis across all phyla. Here, we find a ClC chloride channel is involved in salt concentration chemotaxis of Caenorhabditis elegans. Genetic screening identified two altered-function mutations of clh-1 that disrupt experience-dependent salt chemotaxis. Using genetically encoded fluorescent sensors, we demonstrate that CLH-1 contributes to regulation of intracellular anion and calcium dynamics of salt-sensing neuron, ASER. The mutant CLH-1 reduced responsiveness of ASER to salt stimuli in terms of both temporal resolution and intensity, which disrupted navigation strategies for approaching preferred salt concentrations. Furthermore, other ClC genes appeared to act redundantly in salt chemotaxis. These findings provide insights into the regulatory mechanism of neuronal responsivity by ClCs that contribute to modulation of navigation behavior.
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Affiliation(s)
- Chanhyun Park
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
| | - Yuki Sakurai
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
| | - Hirofumi Sato
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
| | - Shinji Kanda
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
- Laboratory of Physiology, Atmosphere and Ocean Research Institute, The University of TokyoChibaJapan
| | - Yuichi Iino
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
| | - Hirofumi Kunitomo
- Department of Biological Sciences, School of Science, The University of TokyoTokyoJapan
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28
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Totani Y, Nakai J, Hatakeyama D, Ito E. Memory-enhancing effects of short-term fasting. THE EUROPEAN ZOOLOGICAL JOURNAL 2020. [DOI: 10.1080/24750263.2020.1827053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Y. Totani
- Department of Biology, Waseda University, Tokyo, Japan
| | - J. Nakai
- Department of Biology, Waseda University, Tokyo, Japan
| | - D. Hatakeyama
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan
| | - E. Ito
- Department of Biology, Waseda University, Tokyo, Japan
- Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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29
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Martinez BA, Reis Rodrigues P, Nuñez Medina RM, Mondal P, Harrison NJ, Lone MA, Webster A, Gurkar AU, Grill B, Gill MS. An alternatively spliced, non-signaling insulin receptor modulates insulin sensitivity via insulin peptide sequestration in C. elegans. eLife 2020; 9:49917. [PMID: 32096469 PMCID: PMC7041946 DOI: 10.7554/elife.49917] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 01/10/2020] [Indexed: 01/05/2023] Open
Abstract
In the nematode C. elegans, insulin signaling regulates development and aging in response to the secretion of numerous insulin peptides. Here, we describe a novel, non-signaling isoform of the nematode insulin receptor (IR), DAF-2B, that modulates insulin signaling by sequestration of insulin peptides. DAF-2B arises via alternative splicing and retains the extracellular ligand binding domain but lacks the intracellular signaling domain. A daf-2b splicing reporter revealed active regulation of this transcript through development, particularly in the dauer larva, a diapause stage associated with longevity. CRISPR knock-in of mScarlet into the daf-2b genomic locus confirmed that DAF-2B is expressed in vivo and is likely secreted. Genetic studies indicate that DAF-2B influences dauer entry, dauer recovery and adult lifespan by altering insulin sensitivity according to the prevailing insulin milieu. Thus, in C. elegans alternative splicing at the daf-2 locus generates a truncated IR that fine-tunes insulin signaling in response to the environment.
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Affiliation(s)
- Bryan A Martinez
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Pedro Reis Rodrigues
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Ricardo M Nuñez Medina
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Prosenjit Mondal
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Neale J Harrison
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Museer A Lone
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Amanda Webster
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Aditi U Gurkar
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Brock Grill
- Department of Neuroscience, The Scripps Research Institute - Scripps Florida, Jupiter, United States
| | - Matthew S Gill
- Department of Molecular Medicine, The Scripps Research Institute - Scripps Florida, Jupiter, United States
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30
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Wu T, Duan F, Yang W, Liu H, Caballero A, Fernandes de Abreu DA, Dar AR, Alcedo J, Ch'ng Q, Butcher RA, Zhang Y. Pheromones Modulate Learning by Regulating the Balanced Signals of Two Insulin-like Peptides. Neuron 2019; 104:1095-1109.e5. [PMID: 31676170 PMCID: PMC7009321 DOI: 10.1016/j.neuron.2019.09.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/09/2019] [Accepted: 09/06/2019] [Indexed: 02/07/2023]
Abstract
Social environment modulates learning through unknown mechanisms. Here, we report that a pheromone mixture that signals overcrowding inhibits C. elegans from learning to avoid pathogenic bacteria. We find that learning depends on the balanced signaling of two insulin-like peptides (ILPs), INS-16 and INS-4, which act respectively in the pheromone-sensing neuron ADL and the bacteria-sensing neuron AWA. Pheromone exposure inhibits learning by disrupting this balance: it activates ADL and increases expression of ins-16, and this cellular effect reduces AWA activity and AWA-expressed ins-4. The activities of the sensory neurons are required for learning and the expression of the ILPs. Interestingly, pheromones also promote the ingestion of pathogenic bacteria while increasing resistance to the pathogen. Thus, the balance of the ILP signals integrates social information into the learning process as part of a coordinated adaptive response that allows consumption of harmful food during times of high population density.
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Affiliation(s)
- Taihong Wu
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - Fengyun Duan
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - Wenxing Yang
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - He Liu
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - Antonio Caballero
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Diana Andrea Fernandes de Abreu
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Abdul Rouf Dar
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Joy Alcedo
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - QueeLim Ch'ng
- Centre for Developmental Neurobiology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE1 1UL, UK
| | - Rebecca A Butcher
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Yun Zhang
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA.
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31
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Cheng K, Chen YS, Yue CX, Zhang SM, Pei YP, Cheng GR, Liu D, Xu L, Dong HX, Zeng Y. Calsyntenin-1 Negatively Regulates ICAM5 Accumulation in Postsynaptic Membrane and Influences Dendritic Spine Maturation in a Mouse Model of Fragile X Syndrome. Front Neurosci 2019; 13:1098. [PMID: 31680833 PMCID: PMC6813673 DOI: 10.3389/fnins.2019.01098] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 09/30/2019] [Indexed: 11/29/2022] Open
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder that causes intellectual disability, as well as the leading monogenic cause of autism spectrum disorders (ASD), in which neurons show aberrant dendritic spine structure. The reduction/absence of the functional FMRP protein, coded by the X-linked Fmr1 gene in humans, is responsible for the syndrome. Targets of FMRP, CLSTN1, and ICAM5, play critical roles in the maturation of dendritic spines, synapse formation and synaptic plasticity. However, the implication of CLSTN1 and ICAM5 in dendritic spine abnormalities and the underlying neuropathologic processes in FXS remain uninvestigated. In this study, we demonstrated that CLSTN1 co-localizes and co-transports with ICAM5 in cultured cortical neurons. Also we showed that shRNA-mediated downregulation of CLSTN1 in cultured WT neurons increases ICAM5 on the surface of synaptic membrane, subsequently affecting the maturation of dendritic spines. Whereas, normalization of CLSTN1 level in Fmr1 KO neurons reduces ICAM5 abundance and rescues impaired dendritic spine phenotypes. Most importantly, CLSTN1 protein is reduced in the postnatal medial prefrontal cortex of Fmr1 KO mice, which is correlated with increased ICAM5 levels on the surface of synapses and excessive filopodia-like spines. In conclusion, this study demonstrates that CLSTN1 plays a critical role in dendritic spine formation and maturation in FXS by regulating ICAM5 redistribution.
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Affiliation(s)
- Ke Cheng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Yu-Shan Chen
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Chao-Xiong Yue
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Si-Ming Zhang
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Ya-Ping Pei
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Gui-Rong Cheng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Dan Liu
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Lang Xu
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
| | - Hong-Xin Dong
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL, United States
| | - Yan Zeng
- Brain and Cognition Research Institute, Wuhan University of Science and Technology, Wuhan, China.,Big Data Science and Engineering Research Institute, Wuhan University of Science and Technology, Wuhan, China
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32
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Multiple sensory neurons mediate starvation-dependent aversive navigation in Caenorhabditis elegans. Proc Natl Acad Sci U S A 2019; 116:18673-18683. [PMID: 31455735 PMCID: PMC6744849 DOI: 10.1073/pnas.1821716116] [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] [Indexed: 02/07/2023] Open
Abstract
Processing and integrating multiple sensory inputs are essential for generating appropriate behavioral output, where sensory information of food is particularly important. The soil nematode Caenorhabditis elegans remembers salt concentrations that they have experienced under starvation conditions and learn to avoid them by monitoring current salt concentrations with the salt-sensory neuron called ASER. Here, we described how a sensory neuron pair that was not previously implicated, called ASG, plays a pivotal role in driving food-related navigation; sensory input to these 2 sensory neurons is required for navigation to avoid salt concentrations associated with starvation. Our results show how integrated sensory information determines the bias of turning behaviors to efficiently navigate toward food in starved worms. Animals demonstrate flexible behaviors through associative learning based on their experiences. Deciphering the neural mechanisms for sensing and integrating multiple types of sensory information is critical for understanding such behavioral controls. The soil nematode Caenorhabditis elegans avoids salt concentrations it has previously experienced under starvation conditions. Here, we identify a pair of sensory neurons, the ASG neuron pair, which in cooperation with the ASER salt-sensing neuron generate starvation-dependent salt avoidance. Animals whose sensory input is restricted to only ASER failed to show learned avoidance due to inappropriately directed navigation behaviors. However, their navigation through a salt concentration gradient was improved by allowing sensory inputs to ASG in addition to ASER. Detailed behavioral analyses of these animals revealed that input from ASG neurons is required not only for controlling the frequency of initiating a set of sharp turns (called pirouettes) based on detected ambient salt concentrations but also adjusting the migration direction during pirouettes. Optogenetic activation of ASER by ChR2 induced turning behaviors in a salt concentration-dependent manner where presence of intact ASG was important for the starvation-dependent responses. Calcium imaging of the activity of ASG neurons in freely moving worms revealed that ASG is activated upon turning behavior. Our results indicate that ASG neurons cooperate with the ASER neuron to generate destination-directed reorientation in starvation-associated salt concentration avoidance.
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33
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Nagashima T, Iino Y, Tomioka M. DAF-16/FOXO promotes taste avoidance learning independently of axonal insulin-like signaling. PLoS Genet 2019; 15:e1008297. [PMID: 31323047 PMCID: PMC6668909 DOI: 10.1371/journal.pgen.1008297] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 07/31/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022] Open
Abstract
The avoidance of starvation is critical for the survival of most organisms, thus animals change behavior based on past nutritional conditions. Insulin signaling is important for nutritional state-dependent behavioral plasticity, yet the underlying regulatory mechanism at the cellular level remains unclear. Previous studies showed that insulin-like signaling is required for taste avoidance learning, in which the nematode Caenorhabditis elegans avoids salt concentrations encountered under starvation conditions. DAF-2c, a splice isoform of the DAF-2 insulin receptor, functions in the axon of the ASER sensory neuron, which senses changes in salt concentrations. In addition, mutants of a major downstream factor of DAF-2, the forkhead transcription factor O (FOXO) homolog DAF-16, show defects in taste avoidance learning. Interestingly, the defect of the daf-2 mutant is not suppressed by daf-16 mutations in the learning, unlike those in other phenomena, such as longevity and development. Here we show that multiple DAF-16 isoforms function in ASER. By epistasis analysis using a DAF-2c isoform-specific mutant and an activated form of DAF-16, we found that DAF-16 acts in the nucleus in parallel with the DAF-2c-dependent pathway in the axon, indicating that insulin-like signaling acts both in the cell body and axon of a single neuron, ASER. Starvation conditioning induces nuclear translocation of DAF-16 in ASER and degradation of DAF-16 before starvation conditioning causes defects in taste avoidance learning. Forced nuclear localization of DAF-16 in ASER biased chemotaxis towards lower salt concentrtions and this effect required the Gq/PKC pathway and neuropeptide processing enzymes. These data imply that DAF-16/FOXO transmits starvation signals and modulates neuropeptide transmission in the learning. Animals change behavior based on remembered experiences of hunger and appetite. Signaling by insulin and insulin-like peptides in the nervous system plays key roles in behavioral responses to hunger and satiety. In C. elegans, insulin-like signaling in the gustatory sensory neuron ASER regulates learned avoidance of salt concentrations experienced during fasting, which we call taste avoidance learning. DAF-2c, an isoform of the insulin receptor homolog, is localized to the axon of ASER and regulates taste avoidance learning. Here, we show that DAF-16, the forkhead transcription factor O (FOXO) homolog, translocates into the nucleus of ASER during fasting and promotes taste avoidance learning. DAF-16 is negatively regulated by insulin-like signaling independently of axonal DAF-2c signaling. This dual function of insulin-like signaling in the cell body and the axon ensures dynamic changes in behavioral responses after experience of hunger. By genetic analyses using constitutively nuclear-translocated DAF-16, we show that DAF-16 in ASER regulates taste avoidance learning via modulating neuropeptide signaling in the nervous system, which is reminiscent of the function of FOXO in the hypothalamus in the regulation of food-seeking behavior in mammals.
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Affiliation(s)
- Takashi Nagashima
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yuichi Iino
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Masahiro Tomioka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- * E-mail:
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34
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Peymen K, Watteyne J, Borghgraef C, Van Sinay E, Beets I, Schoofs L. Myoinhibitory peptide signaling modulates aversive gustatory learning in Caenorhabditis elegans. PLoS Genet 2019; 15:e1007945. [PMID: 30779740 PMCID: PMC6380545 DOI: 10.1371/journal.pgen.1007945] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 01/07/2019] [Indexed: 11/18/2022] Open
Abstract
Aversive learning and memories are crucial for animals to avoid previously encountered stressful stimuli and thereby increase their chance of survival. Neuropeptides are essential signaling molecules in the brain and are emerging as important modulators of learned behaviors, but their precise role is not well understood. Here, we show that neuropeptides of the evolutionarily conserved MyoInhibitory Peptide (MIP)-family modify salt chemotaxis behavior in Caenorhabditis elegans according to previous experience. MIP signaling, through activation of the G protein-coupled receptor SPRR-2, is required for short-term gustatory plasticity. In addition, MIP/SPRR-2 neuropeptide-receptor signaling mediates another type of aversive gustatory learning called salt avoidance learning that depends on de novo transcription, translation and the CREB transcription factor, all hallmarks of long-term memory. MIP/SPRR-2 signaling mediates salt avoidance learning in parallel with insulin signaling. These findings lay a foundation to investigate the suggested orphan MIP receptor orthologs in deuterostomians, including human GPR139 and GPR142. All animals rely on learning and memory processes to learn from experience and thereby increase their chance of survival. Neuropeptides are essential signaling molecules in the brain and are emerging as important modulators of learning and memory processes. We found that the C. elegans receptor SPRR-2 and its ligands, the MIP-1 neuropeptides—which are members of the evolutionarily conserved myoinhibitory peptide system—are required for aversive gustatory learning. Our results provide a basis for investigations into the poorly characterized MIP systems in deuterostomians, including humans, and suggest a possible function in learning for human MIP signaling.
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Affiliation(s)
- Katleen Peymen
- Department of Biology, University of Leuven (KU Leuven), Leuven, Belgium
| | - Jan Watteyne
- Department of Biology, University of Leuven (KU Leuven), Leuven, Belgium
| | | | - Elien Van Sinay
- Department of Biology, University of Leuven (KU Leuven), Leuven, Belgium
| | - Isabel Beets
- Department of Biology, University of Leuven (KU Leuven), Leuven, Belgium
- * E-mail: (IB); (LS)
| | - Liliane Schoofs
- Department of Biology, University of Leuven (KU Leuven), Leuven, Belgium
- * E-mail: (IB); (LS)
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35
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Marttinen M, Paananen J, Neme A, Mitra V, Takalo M, Natunen T, Paldanius KMA, Mäkinen P, Bremang M, Kurki MI, Rauramaa T, Leinonen V, Soininen H, Haapasalo A, Pike I, Hiltunen M. A multiomic approach to characterize the temporal sequence in Alzheimer's disease-related pathology. Neurobiol Dis 2018; 124:454-468. [PMID: 30557660 DOI: 10.1016/j.nbd.2018.12.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/15/2018] [Accepted: 12/13/2018] [Indexed: 02/08/2023] Open
Abstract
No single-omic approach completely elucidates the multitude of alterations taking place in Alzheimer's disease (AD). Here, we coupled transcriptomic and phosphoproteomic approaches to determine the temporal sequence of changes in mRNA, protein, and phosphopeptide expression levels from human temporal cortical samples, with varying degree of AD-related pathology. This approach highlighted fluctuation in synaptic and mitochondrial function as the earliest pathological events in brain samples with AD-related pathology. Subsequently, increased expression of inflammation and extracellular matrix-associated gene products was observed. Interaction network assembly for the associated gene products, emphasized the complex interplay between these processes and the role of addressing post-translational modifications in the identification of key regulators. Additionally, we evaluate the use of decision trees and random forests in identifying potential biomarkers differentiating individuals with different degree of AD-related pathology. This multiomic and temporal sequence-based approach provides a better understanding of the sequence of events leading to AD.
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Affiliation(s)
- Mikael Marttinen
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Jussi Paananen
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Antonio Neme
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Vikram Mitra
- Proteome Sciences plc, Cobham, London WC1H 9BB, United Kingdom
| | - Mari Takalo
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Teemu Natunen
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Kaisa M A Paldanius
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Petra Mäkinen
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland
| | - Michael Bremang
- Proteome Sciences plc, Cobham, London WC1H 9BB, United Kingdom
| | - Mitja I Kurki
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Psychiatry, Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA; Neurosurgery of Neuro Center, Kuopio University Hospital, Kuopio 70029, Finland
| | - Tuomas Rauramaa
- Department of Pathology, Kuopio University Hospital and University of Eastern Finland, Kuopio 70029, Finland
| | - Ville Leinonen
- Neurosurgery of Neuro Center, Kuopio University Hospital, Kuopio 70029, Finland
| | - Hilkka Soininen
- Neurology of Neuro Center, Kuopio University Hospital, Kuopio 70029, Finland; Institute of Clinical Medicine/Neurology, University of Eastern Finland, Kuopio 70210, Finland
| | - Annakaisa Haapasalo
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio 70211, Finland
| | - Ian Pike
- Proteome Sciences plc, Cobham, London WC1H 9BB, United Kingdom
| | - Mikko Hiltunen
- Institute of Biomedicine, University of Eastern Finland, Kuopio 70210, Finland.
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36
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Phuphisut O, Ajawatanawong P, Limpanont Y, Reamtong O, Nuamtanong S, Ampawong S, Chaimon S, Dekumyoy P, Watthanakulpanich D, Swierczewski BE, Adisakwattana P. Transcriptomic analysis of male and female Schistosoma mekongi adult worms. Parasit Vectors 2018; 11:504. [PMID: 30201055 PMCID: PMC6131826 DOI: 10.1186/s13071-018-3086-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 08/29/2018] [Indexed: 12/23/2022] Open
Abstract
Background Schistosoma mekongi is one of five major causative agents of human schistosomiasis and is endemic to communities along the Mekong River in southern Lao People’s Democratic Republic (Laos) and northern Cambodia. Sporadic cases of schistosomiasis have been reported in travelers and immigrants who have visited endemic areas. Schistosoma mekongi biology and molecular biology is poorly understood, and few S. mekongi gene and transcript sequences are available in public databases. Results Transcriptome sequencing (RNA-Seq) of male and female S. mekongi adult worms (a total of three biological replicates for each sex) were analyzed and the results demonstrated that approximately 304.9 and 363.3 million high-quality clean reads with quality Q30 (> 90%) were obtained from male and female adult worms, respectively. A total of 119,604 contigs were assembled with an average length of 1273 nt and an N50 of 2017 nt. From the contigs, 20,798 annotated protein sequences and 48,256 annotated transcript sequences were obtained using BLASTP and BLASTX searches against the UniProt Trematoda database. A total of 4658 and 3509 transcripts were predominantly expressed in male and female worms, respectively. Male-biased transcripts were mostly involved in structural organization while female-biased transcripts were typically involved in cell differentiation and egg production. Interestingly, pathway enrichment analysis suggested that genes involved in the phosphatidylinositol signaling pathway may play important roles in the cellular processes and reproductive systems of S. mekongi worms. Conclusions We present comparative transcriptomic analyses of male and female S. mekongi adult worms, which provide a global view of the S. mekongi transcriptome as well as insights into differentially-expressed genes associated with each sex. This work provides valuable information and sequence resources for future studies of gene function and for ongoing whole genome sequencing efforts in S. mekongi. Electronic supplementary material The online version of this article (10.1186/s13071-018-3086-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Orawan Phuphisut
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Pravech Ajawatanawong
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Yanin Limpanont
- Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Onrapak Reamtong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Supaporn Nuamtanong
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Sumate Ampawong
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Salisa Chaimon
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paron Dekumyoy
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Dorn Watthanakulpanich
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Brett E Swierczewski
- Department of Enteric Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Poom Adisakwattana
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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Roitenberg N, Bejerano-Sagie M, Boocholez H, Moll L, Marques FC, Golodetzki L, Nevo Y, Elami T, Cohen E. Modulation of caveolae by insulin/IGF-1 signaling regulates aging of Caenorhabditis elegans. EMBO Rep 2018; 19:embr.201745673. [PMID: 29945933 DOI: 10.15252/embr.201745673] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 05/27/2018] [Accepted: 05/29/2018] [Indexed: 11/09/2022] Open
Abstract
Reducing insulin/IGF-1 signaling (IIS) extends lifespan, promotes protein homeostasis (proteostasis), and elevates stress resistance of worms, flies, and mammals. How these functions are orchestrated across the organism is only partially understood. Here, we report that in the nematode Caenorhabditis elegans, the IIS positively regulates the expression of caveolin-1 (cav-1), a gene which is primarily expressed in neurons of the adult worm and underlies the formation of caveolae, a subtype of lipid microdomains that serve as platforms for signaling complexes. Accordingly, IIS reduction lowers cav-1 expression and lessens the quantity of neuronal caveolae. Reduced cav-1 expression extends lifespan and mitigates toxic protein aggregation by modulating the expression of aging-regulating and signaling-promoting genes. Our findings define caveolae as aging-governing signaling centers and underscore the potential for cav-1 as a novel therapeutic target for the promotion of healthy aging.
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Affiliation(s)
- Noa Roitenberg
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Michal Bejerano-Sagie
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Hana Boocholez
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Lorna Moll
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Filipa Carvalhal Marques
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Ludmila Golodetzki
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Yuval Nevo
- Computation Center, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Tayir Elami
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
| | - Ehud Cohen
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel - Canada, The Hebrew University School of Medicine, Jerusalem, Israel
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Thapliyal S, Vasudevan A, Dong Y, Bai J, Koushika SP, Babu K. The C-terminal of CASY-1/Calsyntenin regulates GABAergic synaptic transmission at the Caenorhabditis elegans neuromuscular junction. PLoS Genet 2018. [PMID: 29529030 PMCID: PMC5864096 DOI: 10.1371/journal.pgen.1007263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The C. elegans ortholog of mammalian calsyntenins, CASY-1, is an evolutionarily conserved type-I transmembrane protein that is highly enriched in the nervous system. Mammalian calsyntenins are strongly expressed at inhibitory synapses, but their role in synapse development and function is still elusive. Here, we report a crucial role for CASY-1 in regulating GABAergic synaptic transmission at the C. elegans neuromuscular junction (NMJ). The shorter isoforms of CASY-1; CASY-1B and CASY-1C, express and function in GABA motor neurons where they regulate GABA neurotransmission. Using pharmacological, behavioral, electrophysiological, optogenetic and imaging approaches we establish that GABA release is compromised at the NMJ in casy-1 mutants. Further, we demonstrate that CASY-1 is required to modulate the transport of GABAergic synaptic vesicle (SV) precursors through a possible interaction with the SV motor protein, UNC-104/KIF1A. This study proposes a possible evolutionarily conserved model for the regulation of GABA synaptic functioning by calsyntenins. GABA acts as a major inhibitory neurotransmitter in both vertebrate and invertebrate nervous systems. Despite the potential deregulation of GABA signaling in several neurological disorders, our understanding of the genetic factors that regulate GABAergic synaptic transmission has just started to evolve. Here, we identify a role for a cell adhesion molecule, CASY-1, in regulating GABA signaling at the C. elegans NMJ. We show that the mutants in casy-1 have reduced number of GABA vesicles at the synapse resulting in less GABA release from the presynaptic GABAergic motor neurons. Further, we show that the shorter isoforms of the casy-1 gene; casy-1b and casy-1c that carry a potential kinesin-motor binding domain are responsible for maintaining GABAergic signaling at the synapse. We show a novel interaction of the CASY-1 isoforms with the C- terminal of the UNC-104/KIF1A motor protein that mediates the trafficking of GABAergic synaptic vesicle precursors to the synapse, thus maintaining normal inhibitory signaling at the NMJ.
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Affiliation(s)
- Shruti Thapliyal
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, Punjab, India
| | - Amruta Vasudevan
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Yongming Dong
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 and Department of Biochemistry, University of Washington, Seattle, WA, United Sttaes of America
| | - Jihong Bai
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 and Department of Biochemistry, University of Washington, Seattle, WA, United Sttaes of America
| | - Sandhya P. Koushika
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Kavita Babu
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, Punjab, India
- * E-mail: ,
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Identification of Insulin Receptor Splice Variant B in Neurons by in situ Detection in Human Brain Samples. Sci Rep 2018; 8:4070. [PMID: 29511314 PMCID: PMC5840297 DOI: 10.1038/s41598-018-22434-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 02/22/2018] [Indexed: 12/28/2022] Open
Abstract
Insulin and its receptor are widely expressed in a variety of tissues throughout the body including liver, adipose tissue, liver and brain. The insulin receptor is expressed as two functionally distinct isoforms, differentiated by a single 12 amino acid exon. The two receptor isoforms, designated IR/A and IR/B, are expressed in a highly tissue and cell specific manner and relative proportions of the different isoforms vary during development, aging and disease states. The high degree of similarity between the two isoforms has prevented detailed studies as differentiation of the two isoforms by traditional immunological methods cannot be achieved. We describe here a new in situ RT-PCR/ FISH assay that allows for the visualization of IR/A and IR/B in tissue along with tissue specific markers. We used this new method to show for the first time that IR/A and IR/B are both expressed in neurons in the adult human brain. Thus, we present a method that enables the investigation of IR/A and IR/B insulin receptor isoform expression in situ in various tissues.
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40
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Regulation of Glutamate Signaling in the Sensorimotor Circuit by CASY-1A/Calsyntenin in Caenorhabditis elegans. Genetics 2018; 208:1553-1564. [PMID: 29475851 PMCID: PMC5887148 DOI: 10.1534/genetics.118.300834] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 02/21/2018] [Indexed: 12/02/2022] Open
Abstract
Locomotion is one of the most prominent behaviors in the nematode Caenorhabditis elegans. Neuronal circuits that ultimately produce coordinated dorso-ventral sinusoidal bends mediate this behavior. Synchronized locomotion requires an intricate balance between excitation and inhibition at the neuromuscular junctions (NMJ), the complex cellular and molecular mechanisms of which are not fully understood. Here, we describe the role of a cell adhesion molecule CASY-1, which functions to maintain this balance at the NMJ. In this study, we dissect out mechanisms by which the longer CASY-1A isoform could be affecting the excitatory cholinergic signaling at the NMJ by modulating the activity of sensory neurons. Mutants in casy-1 appear to have hyperactive sensory neurons, resulting in accelerated locomotion and motor circuit activity. These sensory neurons mediate increased motor activity via enhanced glutamate release. Using genetic, pharmacological, and optogenetic manipulations, we establish that CASY-1A is required to monitor the activity of these neurons. Our study illustrates a novel neuromodulatory role of CASY-1-mediated signaling in regulating the excitation-inhibition balance of the motor circuit.
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41
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Templeman NM, Murphy CT. Regulation of reproduction and longevity by nutrient-sensing pathways. J Cell Biol 2018; 217:93-106. [PMID: 29074705 PMCID: PMC5748989 DOI: 10.1083/jcb.201707168] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/02/2017] [Accepted: 10/04/2017] [Indexed: 12/23/2022] Open
Abstract
Nutrients are necessary for life, as they are a crucial requirement for biological processes including reproduction, somatic growth, and tissue maintenance. Therefore, signaling systems involved in detecting and interpreting nutrient or energy levels-most notably, the insulin/insulin-like growth factor 1 (IGF-1) signaling pathway, mechanistic target of rapamycin (mTOR), and adenosine monophosphate-activated protein kinase (AMPK)-play important roles in regulating physiological decisions to reproduce, grow, and age. In this review, we discuss the connections between reproductive senescence and somatic aging and give an overview of the involvement of nutrient-sensing pathways in controlling both reproductive function and lifespan. Although the molecular mechanisms that affect these processes can be influenced by distinct tissue-, temporal-, and pathway-specific signaling events, the progression of reproductive aging and somatic aging is systemically coordinated by integrated nutrient-sensing signaling pathways regulating somatic tissue maintenance in conjunction with reproductive capacity.
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Affiliation(s)
- Nicole M Templeman
- Lewis-Sigler Institute for Integrative Genomics and Department of Molecular Biology, Princeton University, Princeton, NJ
| | - Coleen T Murphy
- Lewis-Sigler Institute for Integrative Genomics and Department of Molecular Biology, Princeton University, Princeton, NJ
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42
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Südhof TC. Synaptic Neurexin Complexes: A Molecular Code for the Logic of Neural Circuits. Cell 2017; 171:745-769. [PMID: 29100073 DOI: 10.1016/j.cell.2017.10.024] [Citation(s) in RCA: 478] [Impact Index Per Article: 68.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 10/04/2017] [Accepted: 10/15/2017] [Indexed: 10/18/2022]
Abstract
Synapses are specialized junctions between neurons in brain that transmit and compute information, thereby connecting neurons into millions of overlapping and interdigitated neural circuits. Here, we posit that the establishment, properties, and dynamics of synapses are governed by a molecular logic that is controlled by diverse trans-synaptic signaling molecules. Neurexins, expressed in thousands of alternatively spliced isoforms, are central components of this dynamic code. Presynaptic neurexins regulate synapse properties via differential binding to multifarious postsynaptic ligands, such as neuroligins, cerebellin/GluD complexes, and latrophilins, thereby shaping the input/output relations of their resident neural circuits. Mutations in genes encoding neurexins and their ligands are associated with diverse neuropsychiatric disorders, especially schizophrenia, autism, and Tourette syndrome. Thus, neurexins nucleate an overall trans-synaptic signaling network that controls synapse properties, which thereby determines the precise responses of synapses to spike patterns in a neuron and circuit and which is vulnerable to impairments in neuropsychiatric disorders.
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Affiliation(s)
- Thomas C Südhof
- Department of Molecular and Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, 265 Campus Drive, CA 94305-5453, USA.
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43
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Tourasse NJ, Millet JRM, Dupuy D. Quantitative RNA-seq meta-analysis of alternative exon usage in C. elegans. Genome Res 2017; 27:2120-2128. [PMID: 29089372 PMCID: PMC5741048 DOI: 10.1101/gr.224626.117] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 10/26/2017] [Indexed: 12/16/2022]
Abstract
Almost 20 years after the completion of the C. elegans genome sequence, gene structure annotation is still an ongoing process with new evidence for gene variants still being regularly uncovered by additional in-depth transcriptome studies. While alternative splice forms can allow a single gene to encode several functional isoforms, the question of how much spurious splicing is tolerated is still heavily debated. Here we gathered a compendium of 1682 publicly available C. elegans RNA-seq data sets to increase the dynamic range of detection of RNA isoforms, and obtained robust measurements of the relative abundance of each splicing event. While most of the splicing reads come from reproducibly detected splicing events, a large fraction of purported junctions is only supported by a very low number of reads. We devised an automated curation method that takes into account the expression level of each gene to discriminate robust splicing events from potential biological noise. We found that rarely used splice sites disproportionately come from highly expressed genes and are significantly less conserved in other nematode genomes than splice sites with a higher usage frequency. Our increased detection power confirmed trans-splicing for at least 84% of C. elegans protein coding genes. The genes for which trans-splicing was not observed are overwhelmingly low expression genes, suggesting that the mechanism is pervasive but not fully captured by organism-wide RNA-seq. We generated annotated gene models including quantitative exon usage information for the entire C. elegans genome. This allows users to visualize at a glance the relative expression of each isoform for their gene of interest.
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Affiliation(s)
- Nicolas J Tourasse
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
| | - Jonathan R M Millet
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
| | - Denis Dupuy
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
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Dynamics of Presynaptic Diacylglycerol in a Sensory Neuron Encode Differences between Past and Current Stimulus Intensity. Cell Rep 2017; 20:2294-2303. [DOI: 10.1016/j.celrep.2017.08.038] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 06/15/2017] [Accepted: 08/03/2017] [Indexed: 11/22/2022] Open
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Ohno H, Yoshida M, Sato T, Kato J, Miyazato M, Kojima M, Ida T, Iino Y. Luqin-like RYamide peptides regulate food-evoked responses in C. elegans. eLife 2017; 6:e28877. [PMID: 28847365 PMCID: PMC5576490 DOI: 10.7554/elife.28877] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 08/08/2017] [Indexed: 12/25/2022] Open
Abstract
Peptide signaling controls many processes involving coordinated actions of multiple organs, such as hormone-mediated appetite regulation. However, the extent to which the mode of action of peptide signaling is conserved in different animals is largely unknown, because many peptides and receptors remain orphan and many undiscovered peptides still exist. Here, we identify two novel Caenorhabditis elegans neuropeptides, LURY-1-1 and LURY-1-2, as endogenous ligands for the neuropeptide receptor-22 (NPR-22). Both peptides derive from the same precursor that is orthologous to invertebrate luqin/arginine-tyrosine-NH2 (RYamide) proneuropeptides. LURY-1 peptides are secreted from two classes of pharyngeal neurons and control food-related processes: feeding, lifespan, egg-laying, and locomotory behavior. We propose that LURY-1 peptides transmit food signals to NPR-22 expressed in feeding pacemaker neurons and a serotonergic neuron. Our results identified a critical role for luqin-like RYamides in feeding-related processes and suggested that peptide-mediated negative feedback is important for satiety regulation in C. elegans.
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Affiliation(s)
- Hayao Ohno
- Department of Biological SciencesGraduate School of Science, The University of TokyoTokyoJapan
| | - Morikatsu Yoshida
- Department of BiochemistryNational Cerebral and Cardiovascular Center Research InstituteOsakaJapan
| | - Takahiro Sato
- Molecular GeneticsInstitute of Life Sciences, Kurume UniversityFukuokaJapan
| | - Johji Kato
- Department of Bioactive PeptidesFrontier Science Research Center, University of MiyazakiMiyazakiJapan
| | - Mikiya Miyazato
- Department of BiochemistryNational Cerebral and Cardiovascular Center Research InstituteOsakaJapan
| | - Masayasu Kojima
- Molecular GeneticsInstitute of Life Sciences, Kurume UniversityFukuokaJapan
| | - Takanori Ida
- Department of Bioactive PeptidesFrontier Science Research Center, University of MiyazakiMiyazakiJapan
- Center for Animal Disease ControlUniversity of MiyazakiMiyazakiJapan
| | - Yuichi Iino
- Department of Biological SciencesGraduate School of Science, The University of TokyoTokyoJapan
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Dysregulation of mRNA Localization and Translation in Genetic Disease. J Neurosci 2017; 36:11418-11426. [PMID: 27911744 DOI: 10.1523/jneurosci.2352-16.2016] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 09/01/2016] [Accepted: 09/02/2016] [Indexed: 11/21/2022] Open
Abstract
RNA-binding proteins (RBPs) acting at various steps in the post-transcriptional regulation of gene expression play crucial roles in neuronal development and synaptic plasticity. Genetic mutations affecting several RBPs and associated factors lead to diverse neurological symptoms, as characterized by neurodevelopmental and neuropsychiatric disorders, neuromuscular and neurodegenerative diseases, and can often be multisystemic diseases. We will highlight the physiological roles of a few specific proteins in molecular mechanisms of cytoplasmic mRNA regulation, and how these processes are dysregulated in genetic disease. Recent advances in computational biology and genomewide analysis, integrated with diverse experimental approaches and model systems, have provided new insights into conserved mechanisms and the shared pathobiology of mRNA dysregulation in disease. Progress has been made to understand the pathobiology of disease mechanisms for myotonic dystrophy, spinal muscular atrophy, and fragile X syndrome, with broader implications for other RBP-associated genetic neurological diseases. This gained knowledge of underlying basic mechanisms has paved the way to the development of therapeutic strategies targeting disease mechanisms.
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Wani S, Kuroyanagi H. An emerging model organism Caenorhabditis elegans for alternative pre-mRNA processing in vivo. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 8. [PMID: 28703462 DOI: 10.1002/wrna.1428] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 05/02/2017] [Accepted: 05/02/2017] [Indexed: 12/13/2022]
Abstract
A nematode Caenorhabditis elegans is an intron-rich organism and up to 25% of its pre-mRNAs are estimated to be alternatively processed. Its compact genomic organization enables construction of fluorescence splicing reporters with intact genomic sequences and visualization of alternative processing patterns of interest in the transparent living animals with single-cell resolution. Genetic analysis with the reporter worms facilitated identification of trans-acting factors and cis-acting elements, which are highly conserved in mammals. Analysis of unspliced and partially spliced pre-mRNAs in vivo raised models for alternative splicing regulation relying on specific order of intron excision. RNA-seq analysis of splicing factor mutants and CLIP-seq analysis of the factors allow global search for target genes in the whole animal. An mRNA surveillance system is not essential for its viability or fertility, allowing analysis of unproductively spliced noncoding mRNAs. These features offer C. elegans as an ideal model organism for elucidating alternative pre-mRNA processing mechanisms in vivo. Examples of isoform-specific functions of alternatively processed genes are summarized. WIREs RNA 2017, 8:e1428. doi: 10.1002/wrna.1428 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Shotaro Wani
- Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hidehito Kuroyanagi
- Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
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The intestinal TORC2 signaling pathway contributes to associative learning in Caenorhabditis elegans. PLoS One 2017; 12:e0177900. [PMID: 28542414 PMCID: PMC5444632 DOI: 10.1371/journal.pone.0177900] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 05/04/2017] [Indexed: 12/25/2022] Open
Abstract
Several types of associative learning are dependent upon the presence or absence of food, and are crucial for the survival of most animals. Target of rapamycin (TOR), a kinase which exists as a component of two complexes, TOR complex 1 (TORC1) and TOR complex 2 (TORC2), is known to act as a nutrient sensor in numerous organisms. However, the in vivo roles of TOR signaling in the nervous system remain largely unclear, partly because its multifunctionality and requirement for survival make it difficult to investigate. Here, using pharmacological inhibitors and genetic analyses, we show that TORC1 and TORC2 contribute to associative learning between salt and food availability in the nematode Caenorhabditis elegans in a process called taste associative learning. Worms migrate to salt concentrations experienced previously during feeding, but they avoid salt concentrations experienced under starvation conditions. Administration of the TOR inhibitor rapamycin causes a behavioral defect after starvation conditioning. Worms lacking either RICT-1 or SINH-1, two TORC2 components, show defects in migration to high salt levels after learning under both fed and starved conditions. We also analyzed the behavioral phenotypes of mutants of the putative TORC1 substrate RSKS-1 (the C. elegans homolog of the mammalian S6 kinase S6K) and the putative TORC2 substrates SGK-1 and PKC-2 (homologs of the serum and glucocorticoid-induced kinase 1, SGK1, and protein kinase C-α, PKC-α, respectively) and found that neuronal RSKS-1 and PKC-2, as well as intestinal SGK-1, are involved in taste associative learning. Our findings shed light on the functions of TOR signaling in behavioral plasticity and provide insight into the mechanisms by which information sensed in the intestine affects the nervous system to modulate food-searching behaviors.
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Tanabe K, Itoh M, Tonoki A. Age-Related Changes in Insulin-like Signaling Lead to Intermediate-Term Memory Impairment in Drosophila. Cell Rep 2017; 18:1598-1605. [DOI: 10.1016/j.celrep.2017.01.053] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 11/20/2016] [Accepted: 01/20/2017] [Indexed: 11/30/2022] Open
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50
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Insulin signaling genes modulate nicotine-induced behavioral responses in Caenorhabditis elegans. Behav Pharmacol 2016; 27:44-9. [PMID: 26317299 DOI: 10.1097/fbp.0000000000000186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Insulin signaling has been suggested to modulate nicotine dependence, but the underlying genetic evidence has been lacking. Here, we used the nematode, Caenorhabditis elegans, to investigate whether genetic alterations in the insulin signaling pathway affect behavioral responses to nicotine. For this, we challenged drug-naive C. elegans with an acute dose of nicotine (100 μmol/l) while recording changes in their locomotion speed. Although nicotine treatment stimulated locomotion speed in wild-type C. elegans, the same treatment reduced locomotion speed in mutants defective in insulin signaling. This phenotype could be suppressed by mutations in daf-16, a gene encoding a FOXO transcription factor that acts downstream of insulin signaling. Our data suggest that insulin signaling genes, daf-2, age-1, pdk-1, akt-1, and akt-2, modulate behavioral responses to nicotine in C. elegans, indicating a genetic link between nicotine behavior and insulin signaling.
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