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Ribeiro Franco PI, do Carmo Neto JR, Guerra RO, Ferreira da Silva PE, Braga YLL, Nunes Celes MR, de Menezes LB, Miguel MP, Machado JR. Melatonin: A look at protozoal and helminths. Biochimie 2024; 219:96-109. [PMID: 37541568 DOI: 10.1016/j.biochi.2023.07.021] [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: 06/19/2023] [Revised: 07/24/2023] [Accepted: 07/29/2023] [Indexed: 08/06/2023]
Abstract
Melatonin is a pleiotropic neurohormone found in different animal, plant, and microorganism species. It is a product resulting from tryptophan metabolism in the pineal gland and is widely known for its ability to synchronize the circadian rhythm to antitumor functions in different types of cancers. The molecular mechanisms responsible for its immunomodulatory, antioxidant and cytoprotective effects involve binding to high-affinity G protein-coupled receptors and interactions with intracellular targets that modulate signal transduction pathways. In vitro and in vivo studies have reported the therapeutic potential of melatonin in different infectious and parasitic diseases. In this review, the protective and pathophysiological roles of melatonin in fighting protozoan and helminth infections and the possible mechanisms involved against these stressors will be discussed.
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Affiliation(s)
- Pablo Igor Ribeiro Franco
- Instituto de Patologia Tropical e Saúde Pública, Programa de Pós-Graduação em Medicina Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil.
| | - José Rodrigues do Carmo Neto
- Instituto de Patologia Tropical e Saúde Pública, Programa de Pós-Graduação em Medicina Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Rhanoica Oliveira Guerra
- Departamento de Biologia Celular, Escola de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Priscilla Elias Ferreira da Silva
- Departamento de Microbiologia, Imunologia e Parasitologia, Instituto de Ciências Biológicas e Naturais, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil
| | - Yarlla Loyane Lira Braga
- Instituto de Patologia Tropical e Saúde Pública, Programa de Pós-Graduação em Medicina Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Mara Rúbia Nunes Celes
- Instituto de Patologia Tropical e Saúde Pública, Programa de Pós-Graduação em Medicina Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Liliana Borges de Menezes
- Escola de Veterinária e Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Federal de Goiás, Goiânia, GO, Brazil; Setor de Patologia Geral, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Marina Pacheco Miguel
- Escola de Veterinária e Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Federal de Goiás, Goiânia, GO, Brazil; Setor de Patologia Geral, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Juliana Reis Machado
- Departamento de Patologia, Genética e Evolução, Instituto de Ciências Biológicas e Naturais, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil
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Migliori ML, Goya ME, Lamberti ML, Silva F, Rota R, Bénard C, Golombek DA. Caenorhabditis elegans as a Promising Model Organism in Chronobiology. J Biol Rhythms 2023; 38:131-147. [PMID: 36680418 DOI: 10.1177/07487304221143483] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Circadian rhythms represent an adaptive feature, ubiquitously found in nature, which grants living beings the ability to anticipate daily variations in their environment. They have been found in a multitude of organisms, ranging from bacteria to fungi, plants, and animals. Circadian rhythms are generated by endogenous clocks that can be entrained daily by environmental cycles such as light and temperature. The molecular machinery of circadian clocks includes a transcriptional-translational feedback loop that takes approximately 24 h to complete. Drosophila melanogaster has been a model organism of choice to understand the molecular basis of circadian clocks. However, alternative animal models are also being adopted, each offering their respective experimental advantages. The nematode Caenorhabditis elegans provides an excellent model for genetics and neuro-behavioral studies, which thanks to its ease of use and manipulation, as well as availability of genetic data and mutant strains, is currently used as a novel model for circadian research. Here, we aim to evaluate C. elegans as a model for chronobiological studies, focusing on its strengths and weaknesses while reviewing the available literature. Possible zeitgebers (including light and temperature) are also discussed. Determining the molecular bases and the neural circuitry involved in the central pacemaker of the C. elegans' clock will contribute to the understanding of its circadian system, becoming a novel model organism for the study of diseases due to alterations of the circadian cycle.
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Affiliation(s)
- María Laura Migliori
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
| | - María Eugenia Goya
- European Institute for the Biology of Aging, University Medical Center Groningen, Groningen, the Netherlands
| | | | - Francisco Silva
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
| | - Rosana Rota
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
| | - Claire Bénard
- Department of Biological Sciences, CERMO-FC Research Center, Universite du Québec à Montréal, Montreál, QC, Canada
| | - Diego Andrés Golombek
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Argentina
- Universidad de San Andrés, Victoria, Argentina
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3
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Li W, Ma L, Shi Y, Wang J, Yin J, Wang D, Luo K, Liu R. Meiosis-mediated reproductive toxicity by fenitrothion in Caenorhabditis elegans from metabolomic perspective. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 253:114680. [PMID: 36857914 DOI: 10.1016/j.ecoenv.2023.114680] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 02/18/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Fenitrothion (FNT), an organophosphorus insecticide, is widely detected in the living environment. The reproductive and endocrine toxicity of FNT to biological communities has been ever reported, but potential mechanism and reproductive toxicity dose effect remain unclear. In our study, we constructed Caenorhabditis elegans model to analyze the reproductive toxicity mechanism of FNT based on metabolomics and evaluated its reproductive toxicity dose effect using benchmark dose (BMD)method. Our results showed that FNT exposure significantly reduced brood size, number of germ cells, and delayed gonadal development in nematodes. Non-targeted metabolomics revealed that FNT exposure caused significant metabolic disturbances in nematodes, leading to a significant reduction in the synthesis of cortisol and melatonin, and the latter played a mediating role in the effects of FNT on number of germ cells. We further found that the levels of these two hormones were significantly negative correlated with the expression of the androgen receptor nhr-69 and affected the meiosis of germ cells by regulating the nhr-69/ fbf-1/2 /gld-3 /fog-1/3 pathway. Meanwhile, the study found the BMDL10s for N2 and him-5 mutant were 0.411 μg/L by number of germ cells and 0.396 μg/L by number of germ cells in the meiotic zone, respectively, providing a more protective reference dose for ecological risk assessment of FNT. This study suggested that FNT can affect androgen receptor expression by inhibiting cortisol and melatonin secretion, which further mediate the meiotic pathway to affect sperm formation and exert reproductive toxicity, and provides a basis for setting reproductive toxicity limits for FNT.
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Affiliation(s)
- Weixi Li
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Lingyi Ma
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Yingchi Shi
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Jia Wang
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Jiechen Yin
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Dayong Wang
- School of Medical, Southeast University, Nanjing 210009, China
| | - Kai Luo
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
| | - Ran Liu
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
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Functional Insights into Protein Kinase A (PKA) Signaling from C. elegans. LIFE (BASEL, SWITZERLAND) 2022; 12:life12111878. [PMID: 36431013 PMCID: PMC9692727 DOI: 10.3390/life12111878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/04/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022]
Abstract
Protein kinase A (PKA), which regulates a diverse set of biological functions downstream of cyclic AMP (cAMP), is a tetramer consisting of two catalytic subunits (PKA-C) and two regulatory subunits (PKA-R). When cAMP binds the PKA-R subunits, the PKA-C subunits are released and interact with downstream effectors. In Caenorhabditis elegans (C. elegans), PKA-C and PKA-R are encoded by kin-1 and kin-2, respectively. This review focuses on the contributions of work in C. elegans to our understanding of the many roles of PKA, including contractility and oocyte maturation in the reproductive system, lipid metabolism, physiology, mitochondrial function and lifespan, and a wide variety of behaviors. C. elegans provides a powerful genetic platform for understanding how this kinase can regulate an astounding variety of physiological responses.
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Abstract
Melatonin (Mel) promotes sleep through G protein-coupled receptors. However, the downstream molecular target(s) is unknown. We identified the Caenorhabditis elegans BK channel SLO-1 as a molecular target of the Mel receptor PCDR-1-. Knockout of pcdr-1, slo-1, or homt-1 (a gene required for Mel synthesis) causes substantially increased neurotransmitter release and shortened sleep duration, and these effects are nonadditive in double knockouts. Exogenous Mel inhibits neurotransmitter release and promotes sleep in wild-type (WT) but not pcdr-1 and slo-1 mutants. In a heterologous expression system, Mel activates the human BK channel (hSlo1) in a membrane-delimited manner in the presence of the Mel receptor MT1 but not MT2 A peptide acting to release free Gβγ also activates hSlo1 in a MT1-dependent and membrane-delimited manner, whereas a Gβλ inhibitor abolishes the stimulating effect of Mel. Our results suggest that Mel promotes sleep by activating the BK channel through a specific Mel receptor and Gβλ.
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Baburina YL, Odinokova IV, Krestinina OV. The Proapoptotic Effect of Melatonin on the Functioning of the Nonspecific Mitochondrial Pore (mPTP) in Rat Mitochondria. NEUROCHEM J+ 2019. [DOI: 10.1134/s1819712419020028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Chen P, Ijomone OM, Lee KH, Aschner M. Caenorhabditis elegans and its applicability to studies on restless legs syndrome. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2019; 84:147-174. [PMID: 31229169 DOI: 10.1016/bs.apha.2018.12.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Restless legs syndrome (RLS) is a common neurological disorder in the United States. This disorder is characterized by an irresistible urge to move the legs, although the symptoms vary in a wide range. The pathobiology of RLS has been linked to iron (Fe) deficiency and dopaminergic (DAergic) dysfunction. Several genetic factors have been reported to increase the risk of RLS. Caenorhabditis elegans (C. elegans) is a well-established animal model with a fully sequenced genome, which is highly conserved with mammals. Given the detailed knowledge of its genomic architecture, ease of genetic manipulation and conserved biosynthetic and metabolic pathways, as well as its small size, ease of maintenance, speedy generation time and large brood size, C. elegans provides numerous advantages in studying RLS-associated gene-environment interactions. Here we will review current knowledge about RLS symptoms, pathology and treatments, and discuss the application of C. elegans in RLS study, including the worm homologous genes and methods that could be performed to advance the pathophysiology RLS.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Omamuyovwi Meashack Ijomone
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, United States; Department of Human Anatomy, Federal University of Technology, Akure, Nigeria
| | - Kun He Lee
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, United States.
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Han Z, Li X, Xu W, She Q, Liang S, Li X, Li Y. Melatonin concentrations in Chinese mitten crabs (Eriocheir sinesis) are affected by artificial photoperiods. BIOL RHYTHM RES 2018. [DOI: 10.1080/09291016.2018.1533725] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Zhibin Han
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Xin Li
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Weibin Xu
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Qiuxin She
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Shudong Liang
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Xiaodong Li
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Yingdong Li
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
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Melatonin Uptake by Cells: An Answer to Its Relationship with Glucose? Molecules 2018; 23:molecules23081999. [PMID: 30103453 PMCID: PMC6222335 DOI: 10.3390/molecules23081999] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/02/2018] [Accepted: 08/06/2018] [Indexed: 02/06/2023] Open
Abstract
Melatonin, N-acetyl-5-methoxytryptamine, is an indole mainly synthesized from tryptophan in the pineal gland and secreted exclusively during the night in all the animals reported to date. While the pineal gland is the major source responsible for this night rise, it is not at all the exclusive production site and many other tissues and organs produce melatonin as well. Likewise, melatonin is not restricted to vertebrates, as its presence has been reported in almost all the phyla from protozoa to mammals. Melatonin displays a large set of functions including adaptation to light: dark cycles, free radical scavenging ability, antioxidant enzyme modulation, immunomodulatory actions or differentiation–proliferation regulatory effects, among others. However, in addition to those important functions, this evolutionary ‘ancient’ molecule still hides further tools with important cellular implications. The major goal of the present review is to discuss the data and experiments that have addressed the relationship between the indole and glucose. Classically, the pineal gland and a pinealectomy were associated with glucose homeostasis even before melatonin was chemically isolated. Numerous reports have provided the molecular components underlying the regulatory actions of melatonin on insulin secretion in pancreatic beta-cells, mainly involving membrane receptors MTNR1A/B, which would be partially responsible for the circadian rhythmicity of insulin in the organism. More recently, a new line of evidence has shown that glucose transporters GLUT/SLC2A are linked to melatonin uptake and its cellular internalization. Beside its binding to membrane receptors, melatonin transportation into the cytoplasm, required for its free radical scavenging abilities, still generates a great deal of debate. Thus, GLUT transporters might constitute at least one of the keys to explain the relationship between glucose and melatonin. These and other potential mechanisms responsible for such interaction are also discussed here.
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The Doubletime Homolog KIN-20 Mainly Regulates let-7 Independently of Its Effects on the Period Homolog LIN-42 in Caenorhabditis elegans. G3-GENES GENOMES GENETICS 2018; 8:2617-2629. [PMID: 29880558 PMCID: PMC6071595 DOI: 10.1534/g3.118.200392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Caenorhabditis elegans (C. elegans) heterochronic pathway, which regulates developmental timing, is thought to be an ancestral form of the circadian clock in other organisms. An essential member of this clock is the Period protein whose homolog, lin-42, in C. elegans is an important heterochronic gene. LIN-42 functions as a transcriptional repressor of multiple genes including the conserved lin-4 and let-7 microRNAs. Like other Period proteins, levels of LIN-42 oscillate throughout development. In other organisms this cycling is controlled in part by phosphorylation. KIN-20 is the C. elegans homolog of the Drosophila Period protein kinase Doubletime. Worms containing a large deletion in kin-20 have a significantly smaller brood size and develop slower than wild type C. elegans Here we analyze the effect of kin-20 on lin-42 phenotypes and microRNA expression. We find that kin-20 RNAi enhances loss-of-function lin-42 mutant phenotypes and that kin-20 mutant worms express lower levels of LIN-42 We also show that kin-20 is important for post-transcriptional regulation of mature let-7 and lin-4 microRNA expression. In addition, the increased level of let-7 found in lin-42(n1089) mutant worms is not maintained after kin-20 RNAi treatment. Instead, let-7 is further repressed when levels of kin-20 and lin-42 are both decreased. Altogether these results suggest that though kin-20 regulates lin-42 and let-7 microRNA, it mainly affects let-7 microRNA expression independently of lin-42 These findings further our understanding of the mechanisms by which these conserved circadian rhythmic genes interact to ultimately regulate rhythmic processes, developmental timing and microRNA biogenesis in C. elegans.
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Mendoza-Vargas L, Báez-Saldaña A, Alvarado R, Fuentes-Pardo B, Flores-Soto E, Solís-Chagoyán H. Circadian rhythm in melatonin release as a mechanism to reinforce the temporal organization of the circadian system in crayfish. INVERTEBRATE NEUROSCIENCE 2017; 17:6. [PMID: 28540583 DOI: 10.1007/s10158-017-0199-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 05/12/2017] [Indexed: 01/25/2023]
Abstract
Melatonin (MEL) is a conserved molecule with respect to its synthesis pathway and functions. In crayfish, MEL content in eyestalks (Ey) increases at night under the photoperiod, and this indoleamine synchronizes the circadian rhythm of electroretinogram amplitude, which is expressed by retinas and controlled by the cerebroid ganglion (CG). The aim of this study was to determine whether MEL content in eyestalks and CG or circulating MEL in hemolymph (He) follows a circadian rhythm under a free-running condition; in addition, it was tested whether MEL might directly influence the spontaneous electrical activity of the CG. Crayfish were maintained under constant darkness and temperature, a condition suitable for studying the intrinsic properties of circadian systems. MEL was quantified in samples obtained from He, Ey, and CG by means of an enzyme-linked immunosorbent assay, and the effect of exogenous MEL on CG spontaneous activity was evaluated by electrophysiological recording. Variation of MEL content in He, Ey, and CG followed a circadian rhythm that peaked at the same circadian time (CT). In addition, a single dose of MEL injected into the crayfish at different CTs reduced the level of spontaneous electrical activity in the CG. Results suggest that the circadian increase in MEL content directly affects the CG, reducing its spontaneous electrical activity, and that MEL might act as a periodical signal to reinforce the organization of the circadian system in crayfish.
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Affiliation(s)
- Leonor Mendoza-Vargas
- Departamento El Hombre Y Su Ambiente, Universidad Autónoma Metropolitana Unidad Xochimilco, CP 04960, Mexico, Mexico
| | - Armida Báez-Saldaña
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Nueva Sede, Universidad Nacional Autónoma de México, CP 04510, Mexico, Mexico
| | - Ramón Alvarado
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, CP 04510, Mexico, Mexico
| | - Beatriz Fuentes-Pardo
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, CP 04510, Mexico, Mexico
| | - Edgar Flores-Soto
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, CP 04510, Mexico, Mexico
| | - Héctor Solís-Chagoyán
- Laboratorio de Neurofarmacología, Instituto Nacional de Psiquiatría Ramón de La Fuente Muñiz, CP 14370, Mexico, D.F, Mexico.
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Ren W, Liu G, Chen S, Yin J, Wang J, Tan B, Wu G, Bazer FW, Peng Y, Li T, Reiter RJ, Yin Y. Melatonin signaling in T cells: Functions and applications. J Pineal Res 2017; 62. [PMID: 28152213 DOI: 10.1111/jpi.12394] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 01/27/2017] [Indexed: 12/21/2022]
Abstract
Melatonin affects a variety of physiological processes including circadian rhythms, cellular redox status, and immune function. Importantly, melatonin significantly influences T-cell-mediated immune responses, which are crucial to protect mammals against cancers and infections, but are associated with pathogenesis of many autoimmune diseases. This review focuses on our current understanding of the significance of melatonin in T-cell biology and the beneficial effects of melatonin in T-cell response-based diseases. In addition to expressing both membrane and nuclear receptors for melatonin, T cells have the four enzymes required for the synthesis of melatonin and produce high levels of melatonin. Meanwhile, melatonin is highly effective in modulating T-cell activation and differentiation, especially for Th17 and Treg cells, and also memory T cells. Mechanistically, the influence of melatonin in T-cell biology is associated with membrane and nuclear receptors as well as receptor-independent pathways, for example, via calcineurin. Several cell signaling pathways, including ERK1/2-C/EBPα, are involved in the regulatory roles of melatonin in T-cell biology. Through modulation in T-cell responses, melatonin exerts beneficial effects in various inflammatory diseases, such as type 1 diabetes, systemic lupus erythematosus, and multiple sclerosis. These findings highlight the importance of melatonin signaling in T-cell fate determination, and T cell-based immune pathologies.
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Affiliation(s)
- Wenkai Ren
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Gang Liu
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
| | - Shuai Chen
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
| | - Jie Yin
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
| | - Jing Wang
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
| | - Bie Tan
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
| | - Guoyao Wu
- Department of Animal Science, Texas A&M University, College Station, TX, USA
| | - Fuller W Bazer
- Department of Animal Science, Texas A&M University, College Station, TX, USA
| | - Yuanyi Peng
- Chongqing Key Laboratory of Forage & Herbivore, College of Animal Science and Technology, Southwest University, Chongqing, China
| | - Tiejun Li
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
- Hunan Co-Innovation Center of Animal Production Safety, CICAPS, Changsha, Hunan, China
| | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Yulong Yin
- Laboratory of Animal Nutrition and Health and Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
- School of Life Science, Hunan Normal University, Changsha, China
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Goya ME, Romanowski A, Caldart CS, Bénard CY, Golombek DA. Circadian rhythms identified in Caenorhabditis elegans by in vivo long-term monitoring of a bioluminescent reporter. Proc Natl Acad Sci U S A 2016; 113:E7837-E7845. [PMID: 27849618 PMCID: PMC5137770 DOI: 10.1073/pnas.1605769113] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Circadian rhythms are based on endogenous clocks that allow organisms to adjust their physiology and behavior by entrainment to the solar day and, in turn, to select the optimal times for most biological variables. Diverse model systems-including mice, flies, fungi, plants, and bacteria-have provided important insights into the mechanisms of circadian rhythmicity. However, the general principles that govern the circadian clock of Caenorhabditis elegans have remained largely elusive. Here we report robust molecular circadian rhythms in C elegans recorded with a bioluminescence assay in vivo and demonstrate the main features of the circadian system of the nematode. By constructing a luciferase-based reporter coupled to the promoter of the suppressor of activated let-60 Ras (sur-5) gene, we show in both population and single-nematode assays that C elegans expresses ∼24-h rhythms that can be entrained by light/dark and temperature cycles. We provide evidence that these rhythms are temperature-compensated and can be re-entrained after phase changes of the synchronizing agents. In addition, we demonstrate that light and temperature sensing requires the photoreceptors LITE and GUR-3, and the cyclic nucleotide-gated channel subunit TAX-2. Our results shed light on C elegans circadian biology and demonstrate evolutionarily conserved features in the circadian system of the nematode.
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Affiliation(s)
- María Eugenia Goya
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes/Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Buenos Aires B1876BXD, Argentina
| | - Andrés Romanowski
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes/Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Buenos Aires B1876BXD, Argentina
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Ciudad Autónoma de Buenos Aires C1405BWE, Argentina
| | - Carlos S Caldart
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes/Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Buenos Aires B1876BXD, Argentina
| | - Claire Y Bénard
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605;
- Department of Biological Sciences University of Quebec at Montreal, Montreal, QC, Canada H2X 1Y4
| | - Diego A Golombek
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes/Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Buenos Aires B1876BXD, Argentina;
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Tan DX, Hardeland R, Back K, Manchester LC, Alatorre-Jimenez MA, Reiter RJ. On the significance of an alternate pathway of melatonin synthesis via 5-methoxytryptamine: comparisons across species. J Pineal Res 2016; 61:27-40. [PMID: 27112772 DOI: 10.1111/jpi.12336] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 04/21/2016] [Indexed: 12/14/2022]
Abstract
Melatonin is a phylogenetically ancient molecule. It is ubiquitously present in almost all organisms from primitive photosynthetic bacteria to humans. Its original primary function is presumable to be that of an antioxidant with other functions of this molecule having been acquired during evolution. The synthetic pathway of melatonin in vertebrates has been extensively studied. It is common knowledge that serotonin is acetylated to form N-acetylserotonin by arylalkylamine N-acetyltransferase (AANAT) or arylamine N-acetyltransferase (SNAT or NAT) and N-acetylserotonin is, subsequently, methylated to melatonin by N-acetylserotonin O-methyltransferase (ASMT; also known as hydroxyindole-O-methyltransferase, HIOMT). This is referred to as a classic melatonin synthetic pathway. Based on new evidence, we feel that this classic melatonin pathway is not generally the prevailing route of melatonin production. An alternate pathway is known to exist, in which serotonin is first O-methylated to 5-methoxytryptamine (5-MT) and, thereafter, 5-MT is N-acetylated to melatonin. Here, we hypothesize that the alternate melatonin synthetic pathway may be more important in certain organisms and under certain conditions. Evidence strongly supports that this alternate pathway prevails in some plants, bacteria, and, perhaps, yeast and may also occur in animals.
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Affiliation(s)
- Dun-Xian Tan
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany
| | - Kyoungwhan Back
- Department of Biotechnology, Bioenergy Research Center, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, South Korea
| | - Lucien C Manchester
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Moises A Alatorre-Jimenez
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Russel J Reiter
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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15
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Escrivá L, Manyes L, Barberà M, Martínez-Torres D, Meca G. Determination of melatonin in Acyrthosiphon pisum aphids by liquid chromatography-tandem mass spectrometry. JOURNAL OF INSECT PHYSIOLOGY 2016; 86:48-53. [PMID: 26778054 DOI: 10.1016/j.jinsphys.2016.01.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 01/11/2016] [Accepted: 01/13/2016] [Indexed: 06/05/2023]
Abstract
Melatonin is a hormone mainly involved in the regulation of circadian and seasonal rhythms in both invertebrates and vertebrates. Despite the identification of melatonin in many insects, its involvement in the insect seasonal response remains unclear. A liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for melatonin analysis in aphids (Acyrthosiphon pisum) for the first time. After comparing two different procedures and five extraction solvents, a sample preparation procedure with a mixture of methanol/water (50:50) was selected for melatonin extraction. The method was validated by analyzing melatonin recovery at three spiked concentrations (5, 50 and 100 pg/mg) and showed satisfactory recoveries (75-110%), and good repeatability, expressed as relative standard deviation (<10%). Limits of detection (LOD) and quantitation (LOQ) were 1 pg/mg and 5 pg/mg, respectively. Eight concentration levels were used for constructing the calibration curves which showed good linearity between LOQ and 200 times LOQ. The validated method was successfully applied to 26 aphid samples demonstrating its usefulness for melatonin determination in insects. This is -to our knowledge- the first identification of melatonin in aphids by LC-MS/MS.
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Affiliation(s)
- Laura Escrivá
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Burjassot, Spain.
| | - Lara Manyes
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Burjassot, Spain
| | - Miquel Barberà
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Valencia, Spain
| | - David Martínez-Torres
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Valencia, Spain
| | - Guiseppe Meca
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Burjassot, Spain
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16
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Winbush A, Gruner M, Hennig GW, van der Linden AM. Long-term imaging of circadian locomotor rhythms of a freely crawling C. elegans population. J Neurosci Methods 2015; 249:66-74. [PMID: 25911068 DOI: 10.1016/j.jneumeth.2015.04.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 04/04/2015] [Accepted: 04/13/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND Locomotor activity is used extensively as a behavioral output to study the underpinnings of circadian rhythms. Recent studies have required a populational approach for the study of circadian rhythmicity in Caenorhabditis elegans locomotion. NEW METHOD We describe an imaging system for long-term automated recording and analysis of locomotion data of multiple free-crawling C. elegans animals on the surface of an agar plate. We devised image analysis tools for measuring specific features related to movement and shape to identify circadian patterns. RESULTS We demonstrate the utility of our system by quantifying circadian locomotor rhythms in wild-type and mutant animals induced by temperature cycles. We show that 13 °C:18 °C (12:12h) cycles are sufficient to entrain locomotor activity of wild-type animals, which persist but are rapidly damped during 13 °C free-running conditions. Animals with mutations in tax-2, a cyclic nucleotide-gated (CNG) ion channel, significantly reduce locomotor activity during entrainment and free-running. COMPARISON WITH EXISTING METHOD(S) Current methods for measuring circadian locomotor activity is generally restricted to recording individual swimming animals of C. elegans, which is a distinct form of locomotion from crawling behavior generally observed in the laboratory. Our system works well with up to 20 crawling adult animals, and allows for a detailed analysis of locomotor activity over long periods of time. CONCLUSIONS Our population-based approach provides a powerful tool for quantification of circadian rhythmicity of C. elegans locomotion, and could allow for a screening system of candidate circadian genes in this model organism.
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Affiliation(s)
- Ari Winbush
- Department of Biology, University of Nevada, Reno, NV 89557, USA.
| | - Matthew Gruner
- Department of Biology, University of Nevada, Reno, NV 89557, USA.
| | - Grant W Hennig
- Department of Physiology and Cell Biology, University of Nevada, School of Medicine, Reno, NV 89557, USA.
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17
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Hiragaki S, Suzuki T, Mohamed AAM, Takeda M. Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT); a key enzyme for physiological and behavioral switch in arthropods. Front Physiol 2015; 6:113. [PMID: 25918505 PMCID: PMC4394704 DOI: 10.3389/fphys.2015.00113] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/25/2015] [Indexed: 11/26/2022] Open
Abstract
The evolution of N-acetyltransfeases (NATs) seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT) has been extensively studied since it leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT), and also xenobiotic reactions (arylamine NAT or simply NAT). NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT) form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO) activity is limited in insects, but NAT-mediated degradation prevails. However, unexpectedly iaaNAT occurs not only among arthropods but also among basal deuterostomia, and is therefore more apomorphic. Our analyses illustrate that iaaNATs has unique physiological roles but at the same time it plays a role in a timezyme function, at least in photoperiodism. Photoperiodism has been considered as a function of circadian system but the detailed molecular mechanism is not well understood. We propose a molecular hypothesis for photoperiodism in Antheraea pernyi based on the transcription regulation of NAT interlocked by the circadian system. Therefore, the enzyme plays both unique and universal roles in insects. The unique role of iaaNATs in physiological regulation urges the targeting of this system for integrated pest management (IPM). We indeed showed a successful example of chemical compound screening with reconstituted enzyme and further attempts seem promising.
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Affiliation(s)
- Susumu Hiragaki
- Graduate School of Agricultural Science, Kobe UniversityKobe, Japan
| | - Takeshi Suzuki
- Department of Biology, The University of Western OntarioLondon, ON, Canada
| | | | - Makio Takeda
- Graduate School of Agricultural Science, Kobe UniversityKobe, Japan
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18
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Abstract
Three properties are most often attributed to the circadian clock: a ca. 24-h free-running rhythm, temperature compensation of the circadian rhythm, and its entrainment to zeitgeber cycles. Relatively few experiments, however, are performed under entrainment conditions. Rather, most chronobiology protocols concern constant conditions. We have turned this paradigm around and used entrainment to study the circadian clock in organisms where a free-running rhythm is weak or lacking. We describe two examples therein: Caenorhabditis elegans and Saccharomyces cerevisiae. By probing the system with zeitgeber cycles that have various structures and amplitudes, we can demonstrate the establishment of systematic entrained phase angles in these organisms. We conclude that entrainment can be utilized to discover hitherto unknown circadian clocks and we discuss the implications of using entrainment more broadly, even in model systems that show robust free-running rhythms.
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Potential conservation of circadian clock proteins in the phylum Nematoda as revealed by bioinformatic searches. PLoS One 2014; 9:e112871. [PMID: 25396739 PMCID: PMC4232591 DOI: 10.1371/journal.pone.0112871] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 10/15/2014] [Indexed: 11/19/2022] Open
Abstract
Although several circadian rhythms have been described in C. elegans, its molecular clock remains elusive. In this work we employed a novel bioinformatic approach, applying probabilistic methodologies, to search for circadian clock proteins of several of the best studied circadian model organisms of different taxa (Mus musculus, Drosophila melanogaster, Neurospora crassa, Arabidopsis thaliana and Synechoccocus elongatus) in the proteomes of C. elegans and other members of the phylum Nematoda. With this approach we found that the Nematoda contain proteins most related to the core and accessory proteins of the insect and mammalian clocks, which provide new insights into the nematode clock and the evolution of the circadian system.
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20
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Cipolla-Neto J, Amaral FG, Afeche SC, Tan DX, Reiter RJ. Melatonin, energy metabolism, and obesity: a review. J Pineal Res 2014; 56:371-81. [PMID: 24654916 DOI: 10.1111/jpi.12137] [Citation(s) in RCA: 354] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 03/17/2014] [Indexed: 12/15/2022]
Abstract
Melatonin is an old and ubiquitous molecule in nature showing multiple mechanisms of action and functions in practically every living organism. In mammals, pineal melatonin functions as a hormone and a chronobiotic, playing a major role in the regulation of the circadian temporal internal order. The anti-obesogen and the weight-reducing effects of melatonin depend on several mechanisms and actions. Experimental evidence demonstrates that melatonin is necessary for the proper synthesis, secretion, and action of insulin. Melatonin acts by regulating GLUT4 expression and/or triggering, via its G-protein-coupled membrane receptors, the phosphorylation of the insulin receptor and its intracellular substrates mobilizing the insulin-signaling pathway. Melatonin is a powerful chronobiotic being responsible, in part, by the daily distribution of metabolic processes so that the activity/feeding phase of the day is associated with high insulin sensitivity, and the rest/fasting is synchronized to the insulin-resistant metabolic phase of the day. Furthermore, melatonin is responsible for the establishment of an adequate energy balance mainly by regulating energy flow to and from the stores and directly regulating the energy expenditure through the activation of brown adipose tissue and participating in the browning process of white adipose tissue. The reduction in melatonin production, as during aging, shift-work or illuminated environments during the night, induces insulin resistance, glucose intolerance, sleep disturbance, and metabolic circadian disorganization characterizing a state of chronodisruption leading to obesity. The available evidence supports the suggestion that melatonin replacement therapy might contribute to restore a more healthy state of the organism.
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Affiliation(s)
- J Cipolla-Neto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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21
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Tevy MF, Giebultowicz J, Pincus Z, Mazzoccoli G, Vinciguerra M. Aging signaling pathways and circadian clock-dependent metabolic derangements. Trends Endocrinol Metab 2013; 24:229-37. [PMID: 23299029 PMCID: PMC3624052 DOI: 10.1016/j.tem.2012.12.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 12/07/2012] [Accepted: 12/12/2012] [Indexed: 12/26/2022]
Abstract
The circadian clock machinery orchestrates organism metabolism to ensure that development, survival, and reproduction are attuned to diurnal environmental variations. For unknown reasons, there is a decline in circadian rhythms with age, concomitant with declines in the overall metabolic tissue homeostasis and changes in the feeding behavior of aged organisms. This disruption of the relationship between the clock and the nutrient-sensing networks might underlie age-related diseases; overall, greater knowledge of the molecular mediators of and variations in clock networks during lifespan may shed light on the aging process and how it may be delayed. In this review we address the complex links between the circadian clock, metabolic (dys)functions, and aging in different model organisms.
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Affiliation(s)
| | - Jadwiga Giebultowicz
- Department of Zoology & Center for Healthy Aging Research, Oregon State University, Corvallis, Oregon, 97331, USA
| | - Zachary Pincus
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA
| | - Gianluigi Mazzoccoli
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital “Casa Sollievo della Sofferenza”, 71013, San Giovanni Rotondo, Italy
| | - Manlio Vinciguerra
- Euro-Mediterranean Institute of Science and Technology, 90139, Palermo, Italy
- Institute of Hepatology, Foundation for Liver Research, C1E 6HX, London, United Kingdom
- Corresponding author: Vinciguerra, M. ()
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22
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Tan DX, Manchester LC, Liu X, Rosales-Corral SA, Acuna-Castroviejo D, Reiter RJ. Mitochondria and chloroplasts as the original sites of melatonin synthesis: a hypothesis related to melatonin's primary function and evolution in eukaryotes. J Pineal Res 2013; 54:127-38. [PMID: 23137057 DOI: 10.1111/jpi.12026] [Citation(s) in RCA: 344] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 10/01/2012] [Indexed: 12/17/2022]
Abstract
Mitochondria and chloroplasts are major sources of free radical generation in living organisms. Because of this, these organelles require strong protection from free radicals and associated oxidative stress. Melatonin is a potent free radical scavenger and antioxidant. It meets the criteria as a mitochondrial and chloroplast antioxidant. Evidence has emerged to show that both mitochondria and chloroplasts may have the capacity to synthesize and metabolize melatonin. The activity of arylalkylamine N-acetyltransferase (AANAT), the reported rate-limiting enzyme in melatonin synthesis, has been identified in mitochondria, and high levels of melatonin have also been found in this organelle. From an evolutionary point of view, the precursor of mitochondria probably is the purple nonsulfur bacterium, particularly, Rhodospirillum rubrum, and chloroplasts are probably the descendents of cyanobacteria. These bacterial species were endosymbionts of host proto-eukaryotes and gradually transformed into cellular organelles, that is, mitochondria and chloroplasts, respectively, thereby giving rise to eukaryotic cells. Of special importance, both purple nonsulfur bacteria (R. rubrum) and cyanobacteria synthesize melatonin. The enzyme activities required for melatonin synthesis have also been detected in these primitive species. It is our hypothesis that mitochondria and chloroplasts are the original sites of melatonin synthesis in the early stage of endosymbiotic organisms; this synthetic capacity was carried into host eukaryotes by the above-mentioned bacteria. Moreover, their melatonin biosynthetic capacities have been preserved during evolution. In most, if not in all cells, mitochondria and chloroplasts may continue to be the primary sites of melatonin generation. Melatonin production in other cellular compartments may have derived from mitochondria and chloroplasts. On the basis of this hypothesis, it is also possible to explain why plants typically have higher melatonin levels than do animals. In plants, both chloroplasts and mitochondria likely synthesize melatonin, while animal cells contain only mitochondria. The high levels of melatonin produced by mitochondria and chloroplasts are used to protect these important cellular organelles against oxidative stress and preserve their physiological functions. The superior beneficial effects of melatonin in both mitochondria and chloroplasts have been frequently reported.
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Affiliation(s)
- Dun-Xian Tan
- Department of Cellular and Structural Biology, The University of Texas, Health Science Center, San Antonio, TX 78229, USA.
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23
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Olmedo M, O’Neill JS, Edgar RS, Valekunja UK, Reddy AB, Merrow M. Circadian regulation of olfaction and an evolutionarily conserved, nontranscriptional marker in Caenorhabditis elegans. Proc Natl Acad Sci U S A 2012; 109:20479-84. [PMID: 23185015 PMCID: PMC3528576 DOI: 10.1073/pnas.1211705109] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Circadian clocks provide a temporal structure to processes from gene expression to behavior in organisms from all phyla. Most clocks are synchronized to the environment by alternations of light and dark. However, many organisms experience only muted daily environmental cycles due to their lightless spatial niches (e.g., caves or soil). This has led to speculation that they may dispense with the daily clock. However, recent reports contradict this notion, showing various behavioral and molecular rhythms in Caenorhabditis elegans and in blind cave fish. Based on the ecology of nematodes, we applied low-amplitude temperature cycles to synchronize populations of animals through development. This entrainment regime reveals rhythms on multiple levels: in olfactory cued behavior, in RNA and protein abundance, and in the oxidation state of a broadly conserved peroxiredoxin protein. Our work links the nematode clock with that of other clock model systems; it also emphasizes the importance of daily rhythms in sensory functions that are likely to impact on organism fitness and population structure.
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Affiliation(s)
- Maria Olmedo
- Department of Molecular Chronobiology, Faculty of Mathematics and Natural Science, University of Groningen, 9474 AG Groningen, The Netherlands
- Institute of Medical Psychology, Medical Faculty, Ludwig-Maximilians-Universität-München, 80336 Munich, Germany; and
| | - John S. O’Neill
- Department of Clinical Neuroscience, Institute of Metabolic Science, National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Rachel S. Edgar
- Department of Clinical Neuroscience, Institute of Metabolic Science, National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Utham K. Valekunja
- Department of Clinical Neuroscience, Institute of Metabolic Science, National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Akhilesh B. Reddy
- Department of Clinical Neuroscience, Institute of Metabolic Science, National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Martha Merrow
- Department of Molecular Chronobiology, Faculty of Mathematics and Natural Science, University of Groningen, 9474 AG Groningen, The Netherlands
- Institute of Medical Psychology, Medical Faculty, Ludwig-Maximilians-Universität-München, 80336 Munich, Germany; and
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