1
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Xie G, Shao Z. SPP-5 affects larval arrest via insulin signaling pathway in Caenorhabditis elegans. J Mol Histol 2024; 55:491-502. [PMID: 38869752 DOI: 10.1007/s10735-024-10205-5] [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: 03/12/2024] [Accepted: 05/18/2024] [Indexed: 06/14/2024]
Abstract
Diapause is an endocrine-mediated metabolic and growth arrest state in response to unfavorable external environments. The nematode Caenorhabditis elegans can enter diapause/arrest during embryonic, larval, or adult stages when subjected to detrimental external environments. Larval stage 1 (L1) arrest happens when animals hatch without food. Previous work has shown that the insulin pathway plays a prominent role in regulating L1 arrest. However, the downstream signal molecular mechanisms and biomarkers are still missing. In this study, we showed that SaPosin-like Protein family member SPP-5 is significantly upregulated during L1 arrest, suggesting that it could act as an L1 arrest biomarker. Using RNA interference we demonstrated that spp-5 knockdown accelerated larval development, while the overexpression resulted in L1 arrest. Consistently, SPP-5 level was significantly up-regulated in the L1 arrest daf-2(e1370) mutants, and spp-5(RNAi) suppressed the daf-2(e1370) induced L1 arrest. These results suggest that SPP-5 can serve as an L1 arrest biomarker and promote the arrest probably via the insulin signaling pathway.
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Affiliation(s)
- Guangjie Xie
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Department of Neurosurgery, Fudan University, Shanghai, China
| | - Zhiyong Shao
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Department of Neurosurgery, Fudan University, Shanghai, China.
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2
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Li Y, Minic Z, Hüttmann N, Khraibah A, Storey KB, Berezovski MV. Proteomic analysis of Rana sylvatica reveals differentially expressed proteins in liver in response to anoxia, dehydration or freezing stress. Sci Rep 2024; 14:15388. [PMID: 38965296 PMCID: PMC11224343 DOI: 10.1038/s41598-024-65417-2] [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: 03/26/2024] [Accepted: 06/20/2024] [Indexed: 07/06/2024] Open
Abstract
Ectothermic animals that live in seasonally cold regions must adapt to seasonal variation and specific environmental conditions. During the winter, some amphibians hibernate on land and encounter limited environmental water, deficient oxygen, and extremely low temperatures that can cause the whole body freezing. These stresses trigger physiological and biochemical adaptations in amphibians that allow them to survive. Rana sylvatica, commonly known as the wood frog, shows excellent freeze tolerance. They can slow their metabolic activity to a near halt and endure freezing of 65-70% of their total body water as extracellular ice during hibernation, returning to normal when the temperatures rise again. To investigate the molecular adaptations of freeze-tolerant wood frogs, a comprehensive proteomic analysis was performed on frog liver tissue after anoxia, dehydration, or freezing exposures using a label-free LC-MS/MS proteomic approach. Quantitative proteomic analysis revealed that 87, 118, and 86 proteins were significantly upregulated in dehydrated, anoxic, and frozen groups, suggesting potential protective functions. The presence of three upregulated enzymes, glutathione S-transferase (GST), aldolase (ALDOA), and sorbitol dehydrogenase (SORD), was also validated. For all enzymes, the specific enzymatic activity was significantly higher in the livers of frozen and anoxic groups than in the controls. This study reveals that GST, ALDOA, and SORD might participate in the freeze tolerance mechanism by contributing to regulating cellular detoxification and energy metabolism.
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Affiliation(s)
- Yingxi Li
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
- John L. Holmes Mass Spectrometry Facility, Faculty of Science, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Zoran Minic
- John L. Holmes Mass Spectrometry Facility, Faculty of Science, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Nico Hüttmann
- John L. Holmes Mass Spectrometry Facility, Faculty of Science, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Abdullah Khraibah
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Kenneth B Storey
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Maxim V Berezovski
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
- John L. Holmes Mass Spectrometry Facility, Faculty of Science, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
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3
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Liu W, Shao H, Qi D, Huang X, Chen J, Zhou L, Guo K. The New Nematicide Cyclobutrifluram Targets the Mitochondrial Succinate Dehydrogenase Complex in Bursaphelenchus xylophilus. Int J Mol Sci 2024; 25:6914. [PMID: 39000026 PMCID: PMC11241274 DOI: 10.3390/ijms25136914] [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: 05/23/2024] [Revised: 06/17/2024] [Accepted: 06/19/2024] [Indexed: 07/14/2024] Open
Abstract
Bursaphelenchus xylophilus is a dangerous quarantine pest that causes extensive damage to pine ecosystems worldwide. Cyclobutrifluram, a succinate dehydrogenase inhibitor (SDHI), is a novel nematicide introduced by Syngenta in 2013. However, the nematocidal effect of cyclobutrifluram against plant-parasitic nematodes remains underexplored. Therefore, here, we aim to address this knowledge gap by evaluating the toxicity, effects, and mode of action of cyclobutrifluram on B. xylophilus. The result shows that cyclobutrifluram is the most effective agent, with an LC50 value of 0.1078 mg·L-1. At an LC20 dose, it significantly reduced the population size to 10.40 × 103 ± 737.56-approximately 1/23 that of the control group. This notable impact may stem from the agent's ability to diminish egg-laying and hatching rates, as well as to impede the nematodes' development. In addition, it has also performed well in the prevention of pine wilt disease, significantly reducing the incidence in greenhouses and in the field. SDH consists of a transmembrane assembly composed of four protein subunits (SDHA to SDHD). Four sdh genes were characterized and proved by RNAi to regulate the spawning capacity, locomotion ability, and body size of B. xylophilus. The mortality of nematodes treated with sdhc-dsRNA significantly decreased upon cyclobutrifluram application. Molecular docking further confirmed that SDHC, a cytochrome-binding protein, is the target. In conclusion, cyclobutrifluram has a good potential for trunk injection against B. xylophilus. This study provides valuable information for the screening and application of effective agents in controlling and preventing PWD in forests.
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Affiliation(s)
- Wenyi Liu
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Hudie Shao
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Danni Qi
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Xiaofang Huang
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Jing Chen
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Lifeng Zhou
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Kai Guo
- College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
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4
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Jiang WI, De Belly H, Wang B, Wong A, Kim M, Oh F, DeGeorge J, Huang X, Guang S, Weiner OD, Ma DK. Early-life stress triggers long-lasting organismal resilience and longevity via tetraspanin. SCIENCE ADVANCES 2024; 10:eadj3880. [PMID: 38266092 PMCID: PMC10807809 DOI: 10.1126/sciadv.adj3880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 12/22/2023] [Indexed: 01/26/2024]
Abstract
Early-life stress experiences can produce lasting impacts on organismal adaptation and fitness. How transient stress elicits memory-like physiological effects is largely unknown. Here, we show that early-life thermal stress strongly up-regulates tsp-1, a gene encoding the conserved transmembrane tetraspanin in C. elegans. TSP-1 forms prominent multimers and stable web-like structures critical for membrane barrier functions in adults and during aging. Increased TSP-1 abundance persists even after transient early-life heat stress. Such regulation requires CBP-1, a histone acetyltransferase that facilitates initial tsp-1 transcription. Tetraspanin webs form regular membrane structures and mediate resilience-promoting effects of early-life thermal stress. Gain-of-function TSP-1 confers marked C. elegans longevity extension and thermal resilience in human cells. Together, our results reveal a cellular mechanism by which early-life thermal stress produces long-lasting memory-like impact on organismal resilience and longevity.
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Affiliation(s)
- Wei I. Jiang
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Henry De Belly
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Bingying Wang
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Andrew Wong
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Minseo Kim
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Fiona Oh
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Jason DeGeorge
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Xinya Huang
- The USTC RNA Institute, Division of Life Sciences and Medicine, Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, China
| | - Shouhong Guang
- The USTC RNA Institute, Division of Life Sciences and Medicine, Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, China
| | - Orion D. Weiner
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Dengke K. Ma
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
- Department of Physiology, University of California, San Francisco, San Francisco, CA, USA
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA
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5
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Wood CR, Wu WT, Yang YS, Yang JS, Xi Y, Yang WJ. From ecology to oncology: To understand cancer stem cell dormancy, ask a Brine shrimp (Artemia). Adv Cancer Res 2023; 158:199-231. [PMID: 36990533 DOI: 10.1016/bs.acr.2022.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The brine shrimp (Artemia), releases embryos that can remain dormant for up to a decade. Molecular and cellular level controlling factors of dormancy in Artemia are now being recognized or applied as active controllers of dormancy (quiescence) in cancers. Most notably, the epigenetic regulation by SET domain-containing protein 4 (SETD4), is revealed as highly conserved and the primary control factor governing the maintenance of cellular dormancy from Artemia embryonic cells to cancer stem cells (CSCs). Conversely, DEK, has recently emerged as the primary factor in the control of dormancy exit/reactivation, in both cases. The latter has been now successfully applied to the reactivation of quiescent CSCs, negating their resistance to therapy and leading to their subsequent destruction in mouse models of breast cancer, without recurrence or metastasis potential. In this review, we introduce the many mechanisms of dormancy from Artemia ecology that have been translated into cancer biology, and herald Artemia's arrival on the model organism stage. We show how Artemia studies have unlocked the mechanisms of the maintenance and termination of cellular dormancy. We then discuss how the antagonistic balance of SETD4 and DEK fundamentally controls chromatin structure and consequently governs CSCs function, chemo/radiotherapy resistance, and dormancy in cancers. Many key stages from transcription factors to small RNAs, tRNA trafficking, molecular chaperones, ion channels, and links with various pathways and aspects of signaling are also noted, all of which link studies in Artemia to those of cancer on a molecular and/or cellular level. We particularly emphasize that the application of such emerging factors as SETD4 and DEK may open new and clear avenues for the treatment for various human cancers.
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Affiliation(s)
- Christopher R Wood
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Wen-Tao Wu
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yao-Shun Yang
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jin-Shu Yang
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yongmei Xi
- The Women's Hospital, and Institute of Genetics, Zhejiang University School of Medicine, Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Hangzhou, Zhejiang, China
| | - Wei-Jun Yang
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
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6
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Ding K, Barretto EC, Johnston M, Lee B, Gallo M, Grewal SS. Transcriptome analysis of FOXO-dependent hypoxia gene expression identifies Hipk as a regulator of low oxygen tolerance in Drosophila. G3 (BETHESDA, MD.) 2022; 12:6749561. [PMID: 36200850 PMCID: PMC9713431 DOI: 10.1093/g3journal/jkac263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/16/2022] [Indexed: 12/05/2022]
Abstract
When exposed to low oxygen or hypoxia, animals must alter their metabolism and physiology to ensure proper cell-, tissue-, and whole-body level adaptations to their hypoxic environment. These alterations often involve changes in gene expression. While extensive work has emphasized the importance of the HIF-1 alpha transcription factor on controlling hypoxia gene expression, less is known about other transcriptional mechanisms. We previously identified the transcription factor FOXO as a regulator of hypoxia tolerance in Drosophila larvae and adults. Here, we use an RNA-sequencing approach to identify FOXO-dependent changes in gene expression that are associated with these tolerance effects. We found that hypoxia altered the expression of over 2,000 genes and that ∼40% of these gene expression changes required FOXO. We discovered that hypoxia exposure led to a FOXO-dependent increase in genes involved in cell signaling, such as kinases, GTPase regulators, and regulators of the Hippo/Yorkie pathway. Among these, we identified homeodomain-interacting protein kinase as being required for hypoxia survival. We also found that hypoxia suppresses the expression of genes involved in ribosome synthesis and egg production, and we showed that hypoxia suppresses tRNA synthesis and mRNA translation and reduces female fecundity. Among the downregulated genes, we discovered that FOXO was required for the suppression of many ribosomal protein genes and genes involved in oxidative phosphorylation, pointing to a role for FOXO in limiting energetically costly processes such as protein synthesis and mitochondrial activity upon hypoxic stress. This work uncovers a widespread role for FOXO in mediating hypoxia changes in gene expression.
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Affiliation(s)
- Kate Ding
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Elizabeth C Barretto
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Michael Johnston
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Byoungchun Lee
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Marco Gallo
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Savraj S Grewal
- Clark H. Smith Brain Tumour Centre, Arnie Charbonneau Cancer Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.,Department of Biochemistry and Molecular Biology Calgary, University of Calgary, Calgary, AB T2N 4N1, Canada
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7
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Rinkevich B, Ballarin L, Martinez P, Somorjai I, Ben‐Hamo O, Borisenko I, Berezikov E, Ereskovsky A, Gazave E, Khnykin D, Manni L, Petukhova O, Rosner A, Röttinger E, Spagnuolo A, Sugni M, Tiozzo S, Hobmayer B. A pan-metazoan concept for adult stem cells: the wobbling Penrose landscape. Biol Rev Camb Philos Soc 2022; 97:299-325. [PMID: 34617397 PMCID: PMC9292022 DOI: 10.1111/brv.12801] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/17/2022]
Abstract
Adult stem cells (ASCs) in vertebrates and model invertebrates (e.g. Drosophila melanogaster) are typically long-lived, lineage-restricted, clonogenic and quiescent cells with somatic descendants and tissue/organ-restricted activities. Such ASCs are mostly rare, morphologically undifferentiated, and undergo asymmetric cell division. Characterized by 'stemness' gene expression, they can regulate tissue/organ homeostasis, repair and regeneration. By contrast, analysis of other animal phyla shows that ASCs emerge at different life stages, present both differentiated and undifferentiated phenotypes, and may possess amoeboid movement. Usually pluri/totipotent, they may express germ-cell markers, but often lack germ-line sequestering, and typically do not reside in discrete niches. ASCs may constitute up to 40% of animal cells, and participate in a range of biological phenomena, from whole-body regeneration, dormancy, and agametic asexual reproduction, to indeterminate growth. They are considered legitimate units of selection. Conceptualizing this divergence, we present an alternative stemness metaphor to the Waddington landscape: the 'wobbling Penrose' landscape. Here, totipotent ASCs adopt ascending/descending courses of an 'Escherian stairwell', in a lifelong totipotency pathway. ASCs may also travel along lower stemness echelons to reach fully differentiated states. However, from any starting state, cells can change their stemness status, underscoring their dynamic cellular potencies. Thus, vertebrate ASCs may reflect just one metazoan ASC archetype.
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Affiliation(s)
- Baruch Rinkevich
- Israel Oceanographic & Limnological ResearchNational Institute of OceanographyPOB 9753, Tel ShikmonaHaifa3109701Israel
| | - Loriano Ballarin
- Department of BiologyUniversity of PadovaVia Ugo Bassi 58/BPadova35121Italy
| | - Pedro Martinez
- Departament de Genètica, Microbiologia i EstadísticaUniversitat de BarcelonaAv. Diagonal 643Barcelona08028Spain
- Institut Català de Recerca i Estudis Avançats (ICREA)Passeig Lluís Companys 23Barcelona08010Spain
| | - Ildiko Somorjai
- School of BiologyUniversity of St AndrewsSt Andrews, FifeKY16 9ST, ScotlandUK
| | - Oshrat Ben‐Hamo
- Israel Oceanographic & Limnological ResearchNational Institute of OceanographyPOB 9753, Tel ShikmonaHaifa3109701Israel
| | - Ilya Borisenko
- Department of Embryology, Faculty of BiologySaint‐Petersburg State UniversityUniversity Embankment, 7/9Saint‐Petersburg199034Russia
| | - Eugene Berezikov
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center GroningenAntonius Deusinglaan 1Groningen9713 AVThe Netherlands
| | - Alexander Ereskovsky
- Department of Embryology, Faculty of BiologySaint‐Petersburg State UniversityUniversity Embankment, 7/9Saint‐Petersburg199034Russia
- Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix Marseille University, CNRS, IRD, Avignon UniversityJardin du Pharo, 58 Boulevard Charles LivonMarseille13007France
- Koltzov Institute of Developmental Biology of Russian Academy of SciencesUlitsa Vavilova, 26Moscow119334Russia
| | - Eve Gazave
- Université de Paris, CNRS, Institut Jacques MonodParisF‐75006France
| | - Denis Khnykin
- Department of PathologyOslo University HospitalBygg 19, Gaustad Sykehus, Sognsvannsveien 21Oslo0188Norway
| | - Lucia Manni
- Department of BiologyUniversity of PadovaVia Ugo Bassi 58/BPadova35121Italy
| | - Olga Petukhova
- Collection of Vertebrate Cell CulturesInstitute of Cytology, Russian Academy of SciencesTikhoretsky Ave. 4St. Petersburg194064Russia
| | - Amalia Rosner
- Israel Oceanographic & Limnological ResearchNational Institute of OceanographyPOB 9753, Tel ShikmonaHaifa3109701Israel
| | - Eric Röttinger
- Université Côte d'Azur, CNRS, INSERM, Institute for Research on Cancer and Aging, Nice (IRCAN)Nice06107France
- Université Côte d'Azur, Federative Research Institute – Marine Resources (IFR MARRES)28 Avenue de ValroseNice06103France
| | - Antonietta Spagnuolo
- Department of Biology and Evolution of Marine OrganismsStazione Zoologica Anton DohrnVilla ComunaleNaples80121Italy
| | - Michela Sugni
- Department of Environmental Science and Policy (ESP)Università degli Studi di MilanoVia Celoria 26Milan20133Italy
| | - Stefano Tiozzo
- Sorbonne Université, CNRS, Laboratoire de Biologie du Développement de Villefranche‐sur‐mer (LBDV)06234 Villefranche‐sur‐MerVillefranche sur MerCedexFrance
| | - Bert Hobmayer
- Institute of Zoology and Center for Molecular Biosciences, University of InnsbruckTechnikerstrInnsbruck256020Austria
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8
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Lantin S, Mendell S, Akkad G, Cohen AN, Apicella X, McCoy E, Beltran-Pardo E, Waltemathe M, Srinivasan P, Joshi PM, Rothman JH, Lubin P. Interstellar space biology via Project Starlight. ACTA ASTRONAUTICA 2022; 190:261-272. [PMID: 36710946 PMCID: PMC9881496 DOI: 10.1016/j.actaastro.2021.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Our ability to explore the cosmos by direct contact has been limited to a small number of lunar and interplanetary missions. However, the NASA Starlight program points a path forward to send small, relativistic spacecraft far outside our solar system via standoff directed-energy propulsion. These miniaturized spacecraft are capable of robotic exploration but can also transport seeds and organisms, marking a profound change in our ability to both characterize and expand the reach of known life. Here we explore the biological and technological challenges of interstellar space biology, focusing on radiation-tolerant microorganisms capable of cryptobiosis. Additionally, we discuss planetary protection concerns and other ethical considerations of sending life to the stars.
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Affiliation(s)
- Stephen Lantin
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, 32611, FL, USA
- Department of Chemical Engineering, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Sophie Mendell
- Department of Molecular, Cellular, and Developmental Biology, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
- College of Creative Studies, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Ghassan Akkad
- Department of Molecular, Cellular, and Developmental Biology, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Alexander N. Cohen
- Department of Physics, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Xander Apicella
- Department of Physics, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Emma McCoy
- Department of Physics, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | | | | | - Prasanna Srinivasan
- Department of Electrical and Computer Engineering, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
- Center for BioEngineering, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Pradeep M. Joshi
- Department of Molecular, Cellular, and Developmental Biology, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Joel H. Rothman
- Department of Molecular, Cellular, and Developmental Biology, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Philip Lubin
- Department of Physics, University of California - Santa Barbara, Santa Barbara, 93106, CA, USA
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9
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Spichal M, Heestand B, Billmyre KK, Frenk S, Mello CC, Ahmed S. Germ granule dysfunction is a hallmark and mirror of Piwi mutant sterility. Nat Commun 2021; 12:1420. [PMID: 33658512 PMCID: PMC7930041 DOI: 10.1038/s41467-021-21635-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 01/29/2021] [Indexed: 01/31/2023] Open
Abstract
In several species, Piwi/piRNA genome silencing defects cause immediate sterility that correlates with transposon expression and transposon-induced genomic instability. In C. elegans, mutations in the Piwi-related gene (prg-1) and other piRNA deficient mutants cause a transgenerational decline in fertility over a period of several generations. Here we show that the sterility of late generation piRNA mutants correlates poorly with increases in DNA damage signaling. Instead, sterile individuals consistently exhibit altered perinuclear germ granules. We show that disruption of germ granules does not activate transposon expression but induces multiple phenotypes found in sterile prg-1 pathway mutants. Furthermore, loss of the germ granule component pgl-1 enhances prg-1 mutant infertility. Environmental restoration of germ granule function for sterile pgl-1 mutants restores their fertility. We propose that Piwi mutant sterility is a reproductive arrest phenotype that is characterized by perturbed germ granule structure and is phenocopied by germ granule dysfunction, independent of genomic instability.
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Affiliation(s)
- Maya Spichal
- grid.410711.20000 0001 1034 1720Department of Genetics, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Department of Biology, University of North Carolina, Chapel Hill, NC USA ,grid.168645.80000 0001 0742 0364RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA USA
| | - Bree Heestand
- grid.410711.20000 0001 1034 1720Department of Genetics, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Department of Biology, University of North Carolina, Chapel Hill, NC USA
| | - Katherine Kretovich Billmyre
- grid.410711.20000 0001 1034 1720Department of Genetics, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Department of Biology, University of North Carolina, Chapel Hill, NC USA ,grid.250820.d0000 0000 9420 1591Present Address: Stowers Institute for Medical Research, Kansas City, MO USA
| | - Stephen Frenk
- grid.410711.20000 0001 1034 1720Department of Genetics, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Department of Biology, University of North Carolina, Chapel Hill, NC USA ,Present Address: Achilles Therapeutics Limited, London, UK
| | - Craig C. Mello
- grid.168645.80000 0001 0742 0364RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA USA ,grid.413575.10000 0001 2167 1581Howard Hughes Medical Institute, Worcester, MA USA
| | - Shawn Ahmed
- grid.410711.20000 0001 1034 1720Department of Genetics, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Department of Biology, University of North Carolina, Chapel Hill, NC USA ,grid.410711.20000 0001 1034 1720Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC USA
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10
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Sousa MI, Correia B, Rodrigues AS, Ramalho-Santos J. Metabolic characterization of a paused-like pluripotent state. Biochim Biophys Acta Gen Subj 2020; 1864:129612. [PMID: 32272203 DOI: 10.1016/j.bbagen.2020.129612] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 03/02/2020] [Accepted: 04/03/2020] [Indexed: 01/07/2023]
Abstract
Embryonic diapause is a conserved reproductive strategy in which development arrests at the blastocyst phase. Recently mammalian target of rapamycin (mTOR) inhibition was shown to induce diapause on mouse blastocysts and a paused-like state on mouse embryonic stem cells (mESCs). In this work, we aimed to further characterize this new paused-pluripotent state, focusing on its glycolytic and oxidative metabolic function. We therefore exposed mESCs, to the mTOR inhibitor INK-128 and evaluated proliferation, pluripotency status and energy-related metabolism, as well as the mTOR inhibition status and translational function. Unexpectedly, in our hands INK-128 did not inhibit the phosphorylation of mTOR or its downstream targets after 48 h. Accordingly, no alterations on protein translational function were observed. Nonetheless, INK-128 could still successfully induce a paused-like state in naïve mESCs regardless of their culturing conditions, by greatly slowing proliferation without affecting pluripotency status. This effect was more prevalent in 2i cultured cells. Interestingly, in this paused-like state, mESCs present a glucose-related hypometabolic profile, which is a hallmark of diapaused blastocysts, with decreased glycolytic and oxidative metabolism and decreased nutrient uptake. Despite the lack of mTOR inhibition and translational suppression, INK-128 still induced a paused-like pluripotent state through cell cycle and metabolic modulation, rather than by translational suppression, suggesting more than one avenue for this type of pluripotent phenotype.
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Affiliation(s)
- Maria Inês Sousa
- CNC-Center for Neuroscience and Cell Biology, CIBB, Azinhaga de Santa Comba, Polo 3, University of Coimbra, Coimbra, Portugal; University of Coimbra, Department of Life Sciences, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - Bibiana Correia
- CNC-Center for Neuroscience and Cell Biology, CIBB, Azinhaga de Santa Comba, Polo 3, University of Coimbra, Coimbra, Portugal
| | - Ana Sofia Rodrigues
- CNC-Center for Neuroscience and Cell Biology, CIBB, Azinhaga de Santa Comba, Polo 3, University of Coimbra, Coimbra, Portugal.
| | - João Ramalho-Santos
- CNC-Center for Neuroscience and Cell Biology, CIBB, Azinhaga de Santa Comba, Polo 3, University of Coimbra, Coimbra, Portugal; University of Coimbra, Department of Life Sciences, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
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11
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Berry BJ, Trewin AJ, Milliken AS, Baldzizhar A, Amitrano AM, Lim Y, Kim M, Wojtovich AP. Optogenetic control of mitochondrial protonmotive force to impact cellular stress resistance. EMBO Rep 2020; 21:e49113. [PMID: 32043300 PMCID: PMC7132214 DOI: 10.15252/embr.201949113] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/26/2019] [Accepted: 01/15/2020] [Indexed: 12/19/2022] Open
Abstract
Mitochondrial respiration generates an electrochemical proton gradient across the mitochondrial inner membrane called protonmotive force (PMF) to drive diverse functions and synthesize ATP. Current techniques to manipulate the PMF are limited to its dissipation; yet, there is no precise and reversible method to increase the PMF. To address this issue, we aimed to use an optogenetic approach and engineered a mitochondria-targeted light-activated proton pump that we name mitochondria-ON (mtON) to selectively increase the PMF in Caenorhabditis elegans. Here we show that mtON photoactivation increases the PMF in a dose-dependent manner, supports ATP synthesis, increases resistance to mitochondrial toxins, and modulates energy-sensing behavior. Moreover, transient mtON activation during hypoxic preconditioning prevents the well-characterized adaptive response of hypoxia resistance. Our results show that optogenetic manipulation of the PMF is a powerful tool to modulate metabolism and cell signaling.
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Affiliation(s)
- Brandon J Berry
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNYUSA
| | - Adam J Trewin
- Department of Anesthesiology and Perioperative MedicineUniversity of Rochester Medical CenterRochesterNYUSA
| | - Alexander S Milliken
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNYUSA
| | - Aksana Baldzizhar
- Department of Anesthesiology and Perioperative MedicineUniversity of Rochester Medical CenterRochesterNYUSA
| | - Andrea M Amitrano
- Department of PathologyUniversity of Rochester Medical CenterRochesterNYUSA
- Department of Microbiology and ImmunologyUniversity of Rochester Medical CenterRochesterNYUSA
| | - Yunki Lim
- Nephrology DivisionDepartment of MedicineSchool of Medicine and DentistryUniversity of Rochester Medical CenterRochesterNYUSA
| | - Minsoo Kim
- Department of PathologyUniversity of Rochester Medical CenterRochesterNYUSA
- Department of Microbiology and ImmunologyUniversity of Rochester Medical CenterRochesterNYUSA
| | - Andrew P Wojtovich
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNYUSA
- Department of Anesthesiology and Perioperative MedicineUniversity of Rochester Medical CenterRochesterNYUSA
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12
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Xiang C, Liu Y, Liu SM, Huang YF, Kong LA, Peng H, Liu MY, Liu J, Peng DL, Huang WK. αβ-Dehydrocurvularin isolated from the fungus Aspergillus welwitschiae effectively inhibited the behaviour and development of the root-knot nematode Meloidogyne graminicola in rice roots. BMC Microbiol 2020; 20:48. [PMID: 32126973 PMCID: PMC7055078 DOI: 10.1186/s12866-020-01738-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/25/2020] [Indexed: 11/22/2022] Open
Abstract
Background The root-knot nematode Meloidogyne graminicola has become a serious threat to rice production as a result of the cultivation changes from transplanting to direct seeding. The nematicidal activity of Aspergillus welwitschiae have been investigated in vitro, and the disease control efficacy of the active compound has been evaluated under greenhouse and field conditions. Results The active compound αβ-dehydrocurvularin (αβ-DC), isolated by nematicidal assay-directed fractionation, showed significant nematicidal activity against M. graminicola, with a median lethal concentration (LC50) value of 122.2 μg mL− 1. αβ-DC effectively decreased the attraction of rice roots to nematodes and the infection of nematodes and also suppressed the development of nematodes under greenhouse conditions. Moreover, αβ-DC efficiently reduced the root gall index under field conditions. Conclusions To our knowledge, this is the first report to describe the nematicidal activity of αβ-DC against M. graminicola. The results obtained under greenhouse and field conditions provide a basis for developing commercial formulations from αβ-DC to control M. graminicola in the future.
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Affiliation(s)
- Chao Xiang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Ying Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.,Bureau of Water Resource in Xingtang County, Shijiazhuang, 050600, People's Republic of China
| | - Shi-Ming Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Ya-Fei Huang
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Ling-An Kong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Huan Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Mao-Yan Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.,College of Plant Protection, Hunan Agricultural University, Changsha, 410128, People's Republic of China
| | - Jing Liu
- College of Plant Protection, Hunan Agricultural University, Changsha, 410128, People's Republic of China
| | - De-Liang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.
| | - Wen-Kun Huang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.
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13
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Carranza-García E, Navarro RE. Insights Into the Hypometabolic Stage Caused by Prolonged Starvation in L4-Adult Caenorhabditis elegans Hermaphrodites. Front Cell Dev Biol 2020; 8:124. [PMID: 32211406 PMCID: PMC7057233 DOI: 10.3389/fcell.2020.00124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 02/12/2020] [Indexed: 11/24/2022] Open
Abstract
Animals alter their reproductive cycles in response to changing nutritional conditions, to ensure that offspring production only occurs under favorable circumstances. These adaptive strategies include reversible hypometabolic states of dormancy such as “arrest” and “diapause.” The free-living nematode Caenorhabditis elegans can arrest its life cycle during some larval stages without modifying its anatomy and physiology until conditions improve but it can also modify its morphological and physiological features to cope with harsh conditions and transition into diapause. The well-defined “dauer” diapause was described more than 40 years ago and has been the subject of comprehensive investigations. The existence of another hypometabolic state, termed adult reproductive diapause (ARD), has been debated after it was first described 10 years ago. Here, we review the current knowledge regarding the effect of food deprivation during the pre-reproductive larval and adult stages on overall organismal homeostasis, highlighting the implications on germ cell maintenance and fertility preservation.
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Affiliation(s)
- E Carranza-García
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Rosa E Navarro
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
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14
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Analysis of Encystment, Excystment, and Cyst Structure in Freshwater Eutardigrade Thulinius ruffoi (Tardigrada, Isohypsibioidea: Doryphoribiidae). DIVERSITY 2020. [DOI: 10.3390/d12020062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Encystment in tardigrades is relatively poorly understood. It is seen as an adaptive strategy evolved to withstand unfavorable environmental conditions. This process is an example of the epigenetic, phenotypic plasticity which is closely linked to the molting process. Thulinius ruffoi is a freshwater eutardigrade and a representative of one of the biggest eutardigrade orders. This species is able to form cysts. The ovoid-shaped cysts of this species are known from nature, but cysts may also be obtained under laboratory conditions. During encystment, the animals undergo profound morphological changes that result in cyst formation. The animals surround their bodies with cuticles that isolate them from the environment. These cuticles form a cuticular capsule (cyst wall) which is composed of three cuticles. Each cuticle is morphologically distinct. The cuticles that form the cuticular capsule are increasingly simplified. During encystment, only one, unmodified and possibly functional buccal-pharyngeal apparatus was found to be formed. Apart from the feeding apparatus, the encysted specimens also possess a set of claws, and their body is covered with its own cuticle. As a consequence, the encysted animals are fully adapted to the active life after leaving the cyst capsule.
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15
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Hannich JT, Haribowo AG, Gentina S, Paillard M, Gomez L, Pillot B, Thibault H, Abegg D, Guex N, Zumbuehl A, Adibekian A, Ovize M, Martinou JC, Riezman H. 1-Deoxydihydroceramide causes anoxic death by impairing chaperonin-mediated protein folding. Nat Metab 2019; 1:996-1008. [PMID: 32694842 DOI: 10.1038/s42255-019-0123-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 09/10/2019] [Indexed: 11/08/2022]
Abstract
Ischaemic heart disease and stroke are the most common causes of death worldwide. Anoxia, defined as the lack of oxygen, is commonly seen in both these pathologies and triggers profound metabolic and cellular changes. Sphingolipids have been implicated in anoxia injury, but the pathomechanism is unknown. Here we show that anoxia-associated injury causes accumulation of the non-canonical sphingolipid 1-deoxydihydroceramide (DoxDHCer). Anoxia causes an imbalance between serine and alanine resulting in a switch from normal serine-derived sphinganine biosynthesis to non-canonical alanine-derived 1-deoxysphinganine. 1-Deoxysphinganine is incorporated into DoxDHCer, which impairs actin folding via the cytosolic chaperonin TRiC, leading to growth arrest in yeast, increased cell death upon anoxia-reoxygenation in worms and ischaemia-reperfusion injury in mouse hearts. Prevention of DoxDHCer accumulation in worms and in mouse hearts resulted in decreased anoxia-induced injury. These findings unravel key metabolic changes during oxygen deprivation and point to novel strategies to avoid tissue damage and death.
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Affiliation(s)
- J Thomas Hannich
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
- Swiss National Center of Competence in Research (NCCR) "Chemical Biology", Geneva, Switzerland
| | - A Galih Haribowo
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
- Swiss National Center of Competence in Research (NCCR) "Chemical Biology", Geneva, Switzerland
| | - Sébastien Gentina
- Department of Cell Biology, University of Geneva, Geneva, Switzerland
| | - Melanie Paillard
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Bron, France
| | - Ludovic Gomez
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Bron, France
| | - Bruno Pillot
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Bron, France
| | - Hélène Thibault
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Bron, France
| | - Daniel Abegg
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL, USA
| | - Nicolas Guex
- Swiss Institute of Bioinformatics, University of Lausanne, Lausanne, Switzerland
- Bioinformatics Competence Center, University of Lausanne, Lausanne, Switzerland
| | - Andreas Zumbuehl
- Swiss National Center of Competence in Research (NCCR) "Chemical Biology", Geneva, Switzerland
- Department of Chemistry, University of Fribourg, Fribourg, Switzerland
| | | | - Michel Ovize
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Bron, France
| | | | - Howard Riezman
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.
- Swiss National Center of Competence in Research (NCCR) "Chemical Biology", Geneva, Switzerland.
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16
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Heestand B, Simon M, Frenk S, Titov D, Ahmed S. Transgenerational Sterility of Piwi Mutants Represents a Dynamic Form of Adult Reproductive Diapause. Cell Rep 2019; 23:156-171. [PMID: 29617657 PMCID: PMC5918633 DOI: 10.1016/j.celrep.2018.03.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 01/24/2018] [Accepted: 03/05/2018] [Indexed: 01/17/2023] Open
Abstract
Environmental stress can induce adult reproductive diapause, a state of developmental arrest that temporarily suspends reproduction. Deficiency for C. elegans Piwi protein PRG-1 results in strains that reproduce for many generations but then become sterile. We found that sterile-generation prg-1/Piwi mutants typically displayed pronounced germ cell atrophy as L4 larvae matured into 1-day-old adults. Atrophied germlines spontaneously reproliferated across the first days of adulthood, and this was accompanied by fertility for day 2–4 adults. Sterile day 5 prg-1 mutant adults remained sterile indefinitely, but providing an alternative food source could restore their fertility. Our data imply that late-generation prg-1 mutants experience a dynamic form of adult reproductive diapause, promoted by stress response, cell death, and RNAi pathways, where delayed fertility and reproductive quiescence represent parallel adaptive developmental outcomes. This may occur in response to a form of “heritable stress” that is transmitted by gametes and epigenetic in nature.
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Affiliation(s)
- Bree Heestand
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Matt Simon
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Stephen Frenk
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Denis Titov
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Shawn Ahmed
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA; Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA.
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17
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Hu CK, Brunet A. The African turquoise killifish: A research organism to study vertebrate aging and diapause. Aging Cell 2018; 17:e12757. [PMID: 29573324 PMCID: PMC5946070 DOI: 10.1111/acel.12757] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2018] [Indexed: 02/06/2023] Open
Abstract
The African turquoise killifish has recently gained significant traction as a new research organism in the aging field. Our understanding of aging has strongly benefited from canonical research organisms—yeast, C. elegans, Drosophila, zebrafish, and mice. Many characteristics that are essential to understand aging—for example, the adaptive immune system or the hypothalamo‐pituitary axis—are only present in vertebrates (zebrafish and mice). However, zebrafish and mice live more than 3 years and their relatively long lifespans are not compatible with high‐throughput studies. Therefore, the turquoise killifish, a vertebrate with a naturally compressed lifespan of only 4–6 months, fills an essential gap to understand aging. With a recently developed genomic and genetic toolkit, the turquoise killifish not only provides practical advantages for lifespan and longitudinal experiments, but also allows more systematic characterizations of the interplay between genetics and environment during vertebrate aging. Interestingly, the turquoise killifish can also enter a long‐term dormant state during development called diapause. Killifish embryos in diapause already have some organs and tissues, and they can last in this state for years, exhibiting exceptional resistance to stress and to damages due to the passage of time. Understanding the diapause state could give new insights into strategies to prevent the damage caused by aging and to better preserve organs, tissues, and cells. Thus, the African turquoise killifish brings two interesting aspects to the aging field—a compressed lifespan and a long‐term resistant diapause state, both of which should spark new discoveries in the field.
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Affiliation(s)
- Chi-Kuo Hu
- Department of Genetics; Stanford University; Stanford CA USA
| | - Anne Brunet
- Department of Genetics; Stanford University; Stanford CA USA
- Glenn Laboratories for the Biology of Aging; Stanford CA USA
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18
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Ko MH, Hwang YS, Rim JS, Han HJ, Han JY. Avian blastoderm dormancy arrests cells in G
2
and suppresses apoptosis. FASEB J 2017; 31:3240-3250. [DOI: 10.1096/fj.201601051rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 03/27/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Mee Hyun Ko
- Department of Agricultural BiotechnologyResearch Institute of Agriculture and Life SciencesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul National University Seoul South Korea
| | - Young Sun Hwang
- Department of Agricultural BiotechnologyResearch Institute of Agriculture and Life SciencesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul National University Seoul South Korea
| | - Jong Seop Rim
- Department of Agricultural BiotechnologyResearch Institute of Agriculture and Life SciencesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul National University Seoul South Korea
| | - Ho Jae Han
- Department of Veterinary PhysiologyCollege of Veterinary MedicineSeoul National University Seoul South Korea
| | - Jae Yong Han
- Department of Agricultural BiotechnologyResearch Institute of Agriculture and Life SciencesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul National University Seoul South Korea
- Institute for Biomedical SciencesShinshu University Minamiminowa Japan
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19
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Renahan T, Hong RL. A species-specific nematocide that results in terminal embryogenesis. ACTA ACUST UNITED AC 2017; 220:3238-3247. [PMID: 28684461 DOI: 10.1242/jeb.159665] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 06/29/2017] [Indexed: 01/20/2023]
Abstract
Nematode-insect interactions are ubiquitous, complex and constantly changing as the host and nematode coevolve. The entomophilic nematode Pristionchus pacificus is found on a myriad beetle species worldwide, although the molecular dynamics of this relationship are largely unknown. To better understand how host cues affect P. pacificus embryogenesis, we characterized the threshold of sensitivity to the pheromone (Z)-7-tetradecen-2-one (ZTDO) by determining the minimum exposure duration and developmental window that results in P. pacificus embryonic lethality. We found early-stage embryos exposed to volatile ZTDO for as few as 4 h all display terminal embryogenesis, characterized by punctuated development up to 48 h later, with abnormal morphology and limited cavity formation. To determine if the pheromone arrests pre-hatching development by suffocating or permeabilizing the eggshells, we raised embryos under anoxic conditions and also examined eggshell permeability using the lipophilic dye FM4-64. We found that asphyxiating the embryos arrested embryogenesis in a reversible manner but did not phenocopy the effects of ZTDO exposure, whereas the ZTDO-induced disruption of embryogenesis did correlate with increased eggshell permeability. The effects of ZTDO are also highly specific, as other lipid insect compounds do not produce any detectable embryocidal effect. The high specificity and unusual teratogenic effect of ZTDO may be important in mediating the host-nematode relationship by regulating P. pacificus development.
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Affiliation(s)
- Tess Renahan
- California State University, Northridge, Department of Biology, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
| | - Ray L Hong
- California State University, Northridge, Department of Biology, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
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20
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Adamson KJ, Wang T, Rotgans BA, Kruangkum T, Kuballa AV, Storey KB, Cummins SF. Genes and associated peptides involved with aestivation in a land snail. Gen Comp Endocrinol 2017; 246:88-98. [PMID: 26497253 DOI: 10.1016/j.ygcen.2015.10.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 10/14/2015] [Accepted: 10/19/2015] [Indexed: 01/01/2023]
Abstract
Some animals can undergo a remarkable transition from active normal life to a dormant state called aestivation; entry into this hypometabolic state ensures that life continues even during long periods of environmental hardship. In this study, we aimed to identify those central nervous system (CNS) peptides that may regulate metabolic suppression leading to aestivation in land snails. Mass spectral-based neuropeptidome analysis of the CNS comparing active and aestivating states, revealed 19 differentially produced peptides; 2 were upregulated in active animals and 17 were upregulated in aestivated animals. Of those, the buccalin neuropeptide was further investigated since there is existing evidence in molluscs that buccalin modulates physiology by muscle contraction. The Theba pisana CNS contains two buccalin transcripts that encode precursor proteins that are capable of releasing numerous buccalin peptides. Of these, Tpi-buccalin-2 is most highly expressed within our CNS transcriptome derived from multiple metabolic states. No significant difference was observed at the level of gene expression levels for Tpi-buccalin-2 between active and aestivated animals, suggesting that regulation may reside at the level of post-translational control of peptide abundance. Spatial gene and peptide expression analysis of aestivated snail CNS demonstrated that buccalin-2 has widespread distribution within regions that control several physiological roles. In conclusion, we provide the first detailed molecular analysis of the peptides and associated genes that are related to hypometabolism in a gastropod snail known to undergo extended periods of aestivation.
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Affiliation(s)
- K J Adamson
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - T Wang
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - B A Rotgans
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - T Kruangkum
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - A V Kuballa
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - K B Storey
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - S F Cummins
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia.
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21
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Lam SM, Wang Z, Li J, Huang X, Shui G. Sequestration of polyunsaturated fatty acids in membrane phospholipids of Caenorhabditis elegans dauer larva attenuates eicosanoid biosynthesis for prolonged survival. Redox Biol 2017; 12:967-977. [PMID: 28499251 PMCID: PMC5429230 DOI: 10.1016/j.redox.2017.05.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 04/28/2017] [Accepted: 05/04/2017] [Indexed: 12/27/2022] Open
Abstract
Mechanistic basis governing the extreme longevity and developmental quiescence of dauer juvenile, a "non-ageing" developmental variant of Caenorhabditis elegans, has remained largely obscure. Using a lipidomic approach comprising multiple reaction monitoring transitions specific to distinct fatty acyl moieties, we demonstrated that in comparison to other developmental stages, the membrane phospholipids of dauer larva contain a unique enrichment of polyunsaturated fatty acids (PUFAs). Esterified PUFAs in phospholipids exhibited temporal accumulation throughout the course of dauer endurance, followed by sharp reductions prior to termination of diapause. Reductions in esterified PUFAs were accompanied by concomitant increases in unbound PUFAs, as well as their corresponding downstream oxidized derivatives (i.e. eicosanoids). Global phospholipidomics has unveiled that PUFA sequestration in membrane phospholipids denotes an essential aspect of dauer dormancy, principally via suppression of eicosanoid production; and a failure to upkeep membrane lipid homeostasis is associated with termination of dauer endurance.
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Affiliation(s)
- Sin Man Lam
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Zehua Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Jie Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Xun Huang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
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22
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Cheng L, Xu S, Xu C, Lu H, Zhang Z, Zhang D, Mu W, Liu F. Effects of trans-2-hexenal on reproduction, growth and behaviour and efficacy against the pinewood nematode, Bursaphelenchus xylophilus. PEST MANAGEMENT SCIENCE 2017; 73:888-895. [PMID: 27414986 DOI: 10.1002/ps.4360] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 07/12/2016] [Accepted: 07/12/2016] [Indexed: 05/02/2023]
Abstract
BACKGROUND Bursaphelenchus xylophilus is a serious quarantined pest that causes severe damage and major economic losses to pine forests. Because of the adverse effects of some traditional nematicides on humans and the environment, the search for new plant toxicants against these nematodes has intensified. Nematicidal activity of trans-2-hexenal, which is a six-carbon aldehyde present in many plants, was tested against the nematode. RESULTS trans-2-Hexenal showed significant efficacy against B. xylophilus in a dose range of 349.5-699 g m-3 by fumigation of pinewood logs. Additionally, it had significant nematicidal activity against different life stages of B. xylophilus in an in vitro test, with second-stage larvae (L2s) being the most sensitive, with an LC50 value of 9.87 µg mL-1 at 48 h. Egg hatch was also significantly inhibited. Further studies revealed that trans-2-hexenal inhibited the reproductive activity of B. xylophilus, with negative effects on reproduction rate and egg numbers. Moreover, trans-2-hexenal reduced the body length of B. xylophilus. Respiratory rate and thrashing behaviour of B. xylophilus also decreased following treatment with this compound. CONCLUSION trans-2-Hexenal had significant nematicidal activity against B. xylophilus, providing a basis for elucidation of the mode of action of trans-2-hexenal against plant-parasitic nematodes in future studies. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Le Cheng
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Shuangyu Xu
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Chunmei Xu
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Hongbao Lu
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Zhengqun Zhang
- College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, China
| | - Daxia Zhang
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Wei Mu
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
| | - Feng Liu
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, Shandong, China
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23
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Abstract
Freeze tolerance is an amazing winter survival strategy used by various amphibians and reptiles living in seasonally cold environments. These animals may spend weeks or months with up to ∼65% of their total body water frozen as extracellular ice and no physiological vital signs, and yet after thawing they return to normal life within a few hours. Two main principles of animal freeze tolerance have received much attention: the production of high concentrations of organic osmolytes (glucose, glycerol, urea among amphibians) that protect the intracellular environment, and the control of ice within the body (the first putative ice-binding protein in a frog was recently identified), but many other strategies of biochemical adaptation also contribute to freezing survival. Discussed herein are recent advances in our understanding of amphibian and reptile freeze tolerance with a focus on cell preservation strategies (chaperones, antioxidants, damage defense mechanisms), membrane transporters for water and cryoprotectants, energy metabolism, gene/protein adaptations, and the regulatory control of freeze-responsive hypometabolism at multiple levels (epigenetic regulation of DNA, microRNA action, cell signaling and transcription factor regulation, cell cycle control, and anti-apoptosis). All are providing a much more complete picture of life in the frozen state.
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Affiliation(s)
| | - Janet M. Storey
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
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24
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Gorr TA. Hypometabolism as the ultimate defence in stress response: how the comparative approach helps understanding of medically relevant questions. Acta Physiol (Oxf) 2017; 219:409-440. [PMID: 27364602 DOI: 10.1111/apha.12747] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/28/2016] [Accepted: 06/28/2016] [Indexed: 12/22/2022]
Abstract
First conceptualized from breath-hold diving mammals, later recognized as the ultimate cell autonomous survival strategy in anoxia-tolerant vertebrates and burrowing or hibernating rodents, hypometabolism is typically recruited by resilient organisms to withstand and recover from otherwise life-threatening hazards. Through the coordinated down-regulation of biosynthetic, proliferative and electrogenic expenditures at times when little ATP can be generated, a metabolism turned 'down to the pilot light' allows the re-balancing of energy demand with supply at a greatly suppressed level in response to noxious exogenous stimuli or seasonal endogenous cues. A unifying hallmark of stress-tolerant organisms, the adaptation effectively prevents lethal depletion of ATP, thus delineating a marked contrast with susceptible species. Along with disengaged macromolecular syntheses, attenuated transmembrane ion shuttling and PO2 -conforming respiration rates, the metabolic slowdown in tolerant species usually culminates in a non-cycling, quiescent phenotype. However, such a reprogramming also occurs in leading human pathophysiologies. Ranging from microbial infections through ischaemia-driven infarcts to solid malignancies, cells involved in these disorders may again invoke hypometabolism to endure conditions non-permissive for growth. At the same time, their reduced activities underlie the frequent development of a general resistance to therapeutic interventions. On the other hand, a controlled induction of hypometabolic and/or hypothermic states by pharmacological means has recently stimulated intense research aimed at improved organ preservation and patient survival in situations requiring acutely administered critical care. The current review article therefore presents an up-to-date survey of concepts and applications of a coordinated and reversibly down-regulated metabolic rate as the ultimate defence in stress responses.
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Affiliation(s)
- T. A. Gorr
- Institute of Veterinary Physiology; Vetsuisse Faculty; University of Zurich; Zurich Switzerland
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25
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Chiang ACY, Yang H, Yamashita YM. spict, a cyst cell-specific gene, regulates starvation-induced spermatogonial cell death in the Drosophila testis. Sci Rep 2017; 7:40245. [PMID: 28071722 PMCID: PMC5223112 DOI: 10.1038/srep40245] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 12/05/2016] [Indexed: 12/21/2022] Open
Abstract
Tissues are maintained in a homeostatic state by balancing the constant loss of old cells with the continued production of new cells. Tissue homeostasis can shift between high and low turnover states to cope with environmental changes such as nutrient availability. Recently, we discovered that the elimination of transit-amplifying cells plays a critical role in maintaining the stem cell population during protein starvation in the Drosophila testis. Here, we identify spict, a gene expressed specifically in differentiating cyst cells, as a regulator of spermatogonial death. Spict is upregulated in cyst cells that phagocytose dying spermatogonia. We propose that phagocytosis and subsequent clearance of dead spermatogonia, which is partly promoted by Spict, contribute to stem cell maintenance during prolonged protein starvation.
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Affiliation(s)
- Ason C-Y Chiang
- Department of Cell and Developmental Biology, Medical School, University of Michigan Ann Arbor, MI 48109.,Life Sciences Institute, University of Michigan Ann Arbor, MI 48109
| | - Heiko Yang
- Life Sciences Institute, University of Michigan Ann Arbor, MI 48109.,Medical Scientist Training Program, University of Michigan Ann Arbor, MI 48109.,Cellular and Molecular Biology Program, University of Michigan Ann Arbor, MI 48109
| | - Yukiko M Yamashita
- Department of Cell and Developmental Biology, Medical School, University of Michigan Ann Arbor, MI 48109.,Life Sciences Institute, University of Michigan Ann Arbor, MI 48109.,Cellular and Molecular Biology Program, University of Michigan Ann Arbor, MI 48109.,Howard Hughes Medical Institute, University of Michigan Ann Arbor, MI 48109
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26
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Cohen-Fix O, Askjaer P. Cell Biology of the Caenorhabditis elegans Nucleus. Genetics 2017; 205:25-59. [PMID: 28049702 PMCID: PMC5216270 DOI: 10.1534/genetics.116.197160] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/09/2016] [Indexed: 12/25/2022] Open
Abstract
Studies on the Caenorhabditis elegans nucleus have provided fascinating insight to the organization and activities of eukaryotic cells. Being the organelle that holds the genetic blueprint of the cell, the nucleus is critical for basically every aspect of cell biology. The stereotypical development of C. elegans from a one cell-stage embryo to a fertile hermaphrodite with 959 somatic nuclei has allowed the identification of mutants with specific alterations in gene expression programs, nuclear morphology, or nuclear positioning. Moreover, the early C. elegans embryo is an excellent model to dissect the mitotic processes of nuclear disassembly and reformation with high spatiotemporal resolution. We review here several features of the C. elegans nucleus, including its composition, structure, and dynamics. We also discuss the spatial organization of chromatin and regulation of gene expression and how this depends on tight control of nucleocytoplasmic transport. Finally, the extensive connections of the nucleus with the cytoskeleton and their implications during development are described. Most processes of the C. elegans nucleus are evolutionarily conserved, highlighting the relevance of this powerful and versatile model organism to human biology.
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Affiliation(s)
- Orna Cohen-Fix
- Laboratory of Molecular and Cellular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Peter Askjaer
- Andalusian Center for Developmental Biology, Consejo Superior de Investigaciones Científicas/Junta de Andalucia/Universidad Pablo de Olavide, 41013 Seville, Spain
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27
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Glucose or Altered Ceramide Biosynthesis Mediate Oxygen Deprivation Sensitivity Through Novel Pathways Revealed by Transcriptome Analysis in Caenorhabditis elegans. G3-GENES GENOMES GENETICS 2016; 6:3149-3160. [PMID: 27507791 PMCID: PMC5068937 DOI: 10.1534/g3.116.031583] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Individuals with type 2 diabetes display metabolic abnormalities, such as hyperglycemia, increased free fatty acids, insulin resistance, and altered ceramide levels, that contribute to vascular dysfunctions and compromised oxygen delivery. Caenorhabditis elegans fed a glucose-supplemented diet or with altered ceramide metabolism, due to a hyl-2 mutation, are sensitive to oxygen deprivation (anoxia). Our experiments showed that the combination of these factors further decreased the anoxia survival. RNA-sequencing analysis was performed to assess how a glucose-supplemented diet and/or a hyl-2 mutation altered the transcriptome. Comparison analysis of transcripts associated with anoxia-sensitive animals [hyl-2(tm2031) mutation or a glucose diet] revealed 199 common transcripts encoded by genes with known or predicted functions involving innate immunity, cuticle function (collagens), or xenobiotic and endobiotic phase I and II detoxification system. Use of RNA interference (RNAi) to target gene products of the xenobiotic and endobiotic phase I and II detoxification system (UDP-glycosyltransferase and Cytochrome p450 genes; ugt-15, ugt-18, ugt-19, ugt-41, ugt-63, cyp-13A12, cyp-25A1, and cyp-33C8) increased anoxia survival in wild-type animals fed a standard diet. Anoxia sensitivity of the hyl-2(tm2031) animals was suppressed by RNAi of cyp-25A1 or cyp-33C8 genes. A glucose diet fed to the P0 hermaphrodite decreased the anoxia survival of its F1 embryos; however, the RNAi of ugt-63 and cyp-33C8 suppressed anoxia sensitivity. These studies provide evidence that the detoxification system impacts oxygen deprivation responses and that C. elegans can be used to model the conserved detoxification system.
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28
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Adamson KJ, Wang T, Rotgans BA, Kuballa AV, Storey KB, Cummins SF. Differential peptide expression in the central nervous system of the land snail Theba pisana, between active and aestivated. Peptides 2016; 80:61-71. [PMID: 26303007 DOI: 10.1016/j.peptides.2015.08.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 08/16/2015] [Accepted: 08/17/2015] [Indexed: 12/25/2022]
Abstract
Hypometabolism is a physiological state of dormancy entered by many animals in times of environmental stress. There are gaps in our understanding of the molecular components used by animals to achieve this metabolic state. The availability of genomic and transcriptome data can be useful to study the process of hypometabolism at the molecular level. In this study, we use the land snail Theba pisana to identify peptides that may be involved in the hypometabolic state known as aestivation. We found a total of 22 neuropeptides in the central nervous system (CNS) that were differentially produced during activity and aestivation based on mass spectral-based neuropeptidome analysis. Of these, 4 were upregulated in active animals and 18 were upregulated in aestivation. A neuropeptide known to regulate muscle contractions in a variety of molluscs, the small cardioactive peptide A (sCAPA), and a peptide of yet unknown function (termed Aestivation Associated Peptide 12) were chosen for further investigation using temporal and spatial expression analysis of the precursor gene and peptide. Both peptides share expression within regions of the CNS cerebral ganglia and suboesophageal ganglia. Relative transcript abundance suggests that regulation of peptide synthesis and secretion is post-transcriptional. In summary, we provide new insights into the molecular basis of the regulation of aestivation in land snails through CNS peptide control.
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Affiliation(s)
- K J Adamson
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - T Wang
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - B A Rotgans
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - A V Kuballa
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - K B Storey
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - S F Cummins
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia.
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29
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Yang H, Yamashita YM. The regulated elimination of transit-amplifying cells preserves tissue homeostasis during protein starvation in Drosophila testis. Development 2015; 142:1756-66. [PMID: 25968311 DOI: 10.1242/dev.122663] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
How tissues adapt to varying nutrient conditions is of fundamental importance for robust tissue homeostasis throughout the life of an organism, but the underlying mechanisms are poorly understood. Here, we show that Drosophila testis responds to protein starvation by eliminating transit-amplifying spermatogonia (SG) while maintaining a reduced pool of actively proliferating germline stem cells (GSCs). During protein starvation, SG die in a manner that is mediated by the apoptosis of somatic cyst cells (CCs) that encapsulate SG and regulate their development. Strikingly, GSCs cannot be maintained during protein starvation when CC-mediated SG death is inhibited, leading to an irreversible collapse of tissue homeostasis. We propose that the regulated elimination of transit-amplifying cells is essential to preserve stem cell function and tissue homeostasis during protein starvation.
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Affiliation(s)
- Heiko Yang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109-2219, USA
| | - Yukiko M Yamashita
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109-2219, USA Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-2216, USA Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA
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30
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Abstract
For many animals, survival of severe environmental stress (e.g. to extremes of heat or cold, drought, oxygen limitation, food deprivation) is aided by entry into a hypometabolic state. Strong depression of metabolic rate, often to only 1–20% of normal resting rate, is a core survival strategy of multiple forms of hypometabolism across the animal kingdom, including hibernation, anaerobiosis, aestivation and freeze tolerance. Global biochemical controls are needed to suppress and reprioritize energy use; one such well-studied control is reversible protein phosphorylation. Recently, we turned our attention to the idea that mechanisms previously associated mainly with epigenetic regulation can also contribute to reversible suppression of gene expression in hypometabolic states. Indeed, situations as diverse as mammalian hibernation and turtle anoxia tolerance show coordinated changes in histone post-translational modifications (acetylation, phosphorylation) and activities of histone deacetylases, consistent with their use as mechanisms for suppressing gene expression during hypometabolism. Other potential mechanisms of gene silencing in hypometabolic states include altered expression of miRNAs that can provide post-transcriptional suppression of mRNA translation and the formation of ribonuclear protein bodies in the nucleus and cytoplasm to allow storage of mRNA transcripts until animals rouse themselves again. Furthermore, mechanisms first identified in epigenetic regulation (e.g. protein acetylation) are now proving to apply to many central metabolic enzymes (e.g. lactate dehydrogenase), suggesting a new layer of regulatory control that can contribute to coordinating the depression of metabolic rate.
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Affiliation(s)
- Kenneth B. Storey
- Institute of Biochemistry and Departments of Biology and Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
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31
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Flibotte JJ, Jablonski AM, Kalb RG. Oxygen sensing neurons and neuropeptides regulate survival after anoxia in developing C. elegans. PLoS One 2014; 9:e101102. [PMID: 24967811 PMCID: PMC4072718 DOI: 10.1371/journal.pone.0101102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 06/02/2014] [Indexed: 11/18/2022] Open
Abstract
Hypoxic brain injury remains a major source of neurodevelopmental impairment for both term and preterm infants. The perinatal period is a time of rapid transition in oxygen environments and developmental resetting of oxygen sensing. The relationship between neural oxygen sensing ability and hypoxic injury has not been studied. The oxygen sensing circuitry in the model organism C. elegans is well understood. We leveraged this information to investigate the effects of impairments in oxygen sensing on survival after anoxia. There was a significant survival advantage in developing worms specifically unable to sense oxygen shifts below their preferred physiologic range via genetic ablation of BAG neurons, which appear important for conferring sensitivity to anoxia. Oxygen sensing that is mediated through guanylate cyclases (gcy-31, 33, 35) is unlikely to be involved in conferring this sensitivity. Additionally, animals unable to process or elaborate neuropeptides displayed a survival advantage after anoxia. Based on these data, we hypothesized that elaboration of neuropeptides by BAG neurons sensitized animals to anoxia, but further experiments indicate that this is unlikely to be true. Instead, it seems that neuropeptides and signaling from oxygen sensing neurons operate through independent mechanisms, each conferring sensitivity to anoxia in wild type animals.
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Affiliation(s)
- John J. Flibotte
- Department of Pediatrics, Division of Neonatology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Angela M. Jablonski
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Robert G. Kalb
- Department of Pediatrics, Division of Neurology, Research Institute, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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32
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Padilla PA, Garcia AM, Ladage ML, Toni LS. Caenorhabditis elegans: An Old Genetic Model Can Learn New Epigenetic Tricks. Integr Comp Biol 2014; 54:52-60. [DOI: 10.1093/icb/icu039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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33
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Kearn J, Ludlow E, Dillon J, O'Connor V, Holden-Dye L. Fluensulfone is a nematicide with a mode of action distinct from anticholinesterases and macrocyclic lactones. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2014; 109:44-57. [PMID: 24581383 DOI: 10.1016/j.pestbp.2014.01.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/21/2014] [Accepted: 01/22/2014] [Indexed: 06/03/2023]
Abstract
Plant parasitic nematodes infest crops and present a threat to food security worldwide. Currently available chemical controls e.g. methyl bromide, organophosphates and carbamates have an unacceptable level of toxicity to non-target organisms and are being withdrawn from use. Fluensulfone is a new nematicide of the fluoroalkenyl thioether group that has significantly reduced environmental impact with low toxicity to non-target insects and mammals. Here, we show that the model genetic organism Caenorhabditis elegans is susceptible to the irreversible nematicidal effects of fluensulfone. Whilst the dose required is higher than that which has nematicidal activity against Meloidogyne spp. the profile of effects on motility, egg-hatching and survival is similar to that reported for plant parasitic nematodes. C. elegans thus provides a tractable experimental paradigm to analyse the effects of fluensulfone on nematode behaviour. We find that fluensulfone has pleiotropic actions and inhibits development, egg-laying, egg-hatching, feeding and locomotion. In the case of feeding and locomotion, an early excitation precedes the gross inhibition. The profile of these effects is notably distinct from other classes of anthelmintic and nematicide: the inhibition of motility caused by fluensulfone is not accompanied by the hypercontraction which is characteristic of organophosphates and carbamates and C. elegans mutants that are resistant to the carbamate aldicarb and the macrocyclic lactone ivermectin retain susceptibility to fluensulfone. These data indicate fluensulfone's mode of action is distinct from currently available nematicides and it therefore presents a promising new chemical entity for crop protection.
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Affiliation(s)
- James Kearn
- Centre for Biological Sciences, University of Southampton, Building 85, University Road, Southampton SO17 1BJ, United Kingdom
| | - Elizabeth Ludlow
- Centre for Biological Sciences, University of Southampton, Building 85, University Road, Southampton SO17 1BJ, United Kingdom
| | - James Dillon
- Centre for Biological Sciences, University of Southampton, Building 85, University Road, Southampton SO17 1BJ, United Kingdom
| | - Vincent O'Connor
- Centre for Biological Sciences, University of Southampton, Building 85, University Road, Southampton SO17 1BJ, United Kingdom
| | - Lindy Holden-Dye
- Centre for Biological Sciences, University of Southampton, Building 85, University Road, Southampton SO17 1BJ, United Kingdom.
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34
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Ghose P, Park EC, Tabakin A, Salazar-Vasquez N, Rongo C. Anoxia-reoxygenation regulates mitochondrial dynamics through the hypoxia response pathway, SKN-1/Nrf, and stomatin-like protein STL-1/SLP-2. PLoS Genet 2013; 9:e1004063. [PMID: 24385935 PMCID: PMC3873275 DOI: 10.1371/journal.pgen.1004063] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/12/2013] [Indexed: 12/04/2022] Open
Abstract
Many aerobic organisms encounter oxygen-deprived environments and thus must have adaptive mechanisms to survive such stress. It is important to understand how mitochondria respond to oxygen deprivation given the critical role they play in using oxygen to generate cellular energy. Here we examine mitochondrial stress response in C. elegans, which adapt to extreme oxygen deprivation (anoxia, less than 0.1% oxygen) by entering into a reversible suspended animation state of locomotory arrest. We show that neuronal mitochondria undergo DRP-1-dependent fission in response to anoxia and undergo refusion upon reoxygenation. The hypoxia response pathway, including EGL-9 and HIF-1, is not required for anoxia-induced fission, but does regulate mitochondrial reconstitution during reoxygenation. Mutants for egl-9 exhibit a rapid refusion of mitochondria and a rapid behavioral recovery from suspended animation during reoxygenation; both phenotypes require HIF-1. Mitochondria are significantly larger in egl-9 mutants after reoxygenation, a phenotype similar to stress-induced mitochondria hyperfusion (SIMH). Anoxia results in mitochondrial oxidative stress, and the oxidative response factor SKN-1/Nrf is required for both rapid mitochondrial refusion and rapid behavioral recovery during reoxygenation. In response to anoxia, SKN-1 promotes the expression of the mitochondrial resident protein Stomatin-like 1 (STL-1), which helps facilitate mitochondrial dynamics following anoxia. Our results suggest the existence of a conserved anoxic stress response involving changes in mitochondrial fission and fusion. Oxygen deprivation plays a role in multiple human diseases ranging from heart attack, ischemic stroke, and traumatic injury. Aerobic organisms use oxygen to generate cellular energy in mitochondria; thus, oxygen deprivation results in energy depletion. Low oxygen can be catastrophic in tissues like the nervous system, which has high-energy demands and few glycolytic reserves. By contrast, other cells, including stem cells and cancerous cells within tumors, adapt and thrive in low oxygen. We are just beginning to understand how different organisms and even different cell types within the same organism respond to low oxygen conditions. The response of mitochondria to oxygen deprivation is particularly critical given their role in aerobic energy production. In addition, mitochondria actively injure cells during oxygen deprivation through the generation of reactive oxygen species, the disruption of calcium homeostasis, and the activation of cell death pathways. Here we use a genetic approach to show that mitochondria undergo fission during oxygen deprivation and refusion upon oxygen restoration. The hypoxia response pathway and the oxidative stress response pathway together modulate this response. We identify a new factor, stomatin-like protein, as a promoter of mitochondrial fusion in response to oxygen deprivation stress. Our findings uncover a new mechanism – regulated mitochondrial dynamics – by which cells adapt to oxygen deprivation stress.
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Affiliation(s)
- Piya Ghose
- The Waksman Institute, Department of Genetics, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
- The Graduate Program in Neuroscience, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
| | - Eun Chan Park
- The Waksman Institute, Department of Genetics, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
| | - Alexandra Tabakin
- The Waksman Institute, Department of Genetics, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
| | - Nathaly Salazar-Vasquez
- The Waksman Institute, Department of Genetics, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
- The Graduate Program in Genetics and Microbiology, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
| | - Christopher Rongo
- The Waksman Institute, Department of Genetics, Rutgers The State University of New Jersey, Piscataway, New Jersey, United States of America
- * E-mail:
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35
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Flatt T, Amdam GV, Kirkwood TBL, Omholt SW. Life-history evolution and the polyphenic regulation of somatic maintenance and survival. QUARTERLY REVIEW OF BIOLOGY 2013; 88:185-218. [PMID: 24053071 DOI: 10.1086/671484] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Here we discuss life-history evolution from the perspective of adaptive phenotypic plasticity, with a focus on polyphenisms for somatic maintenance and survival. Polyphenisms are adaptive discrete alternative phenotypes that develop in response to changes in the environment. We suggest that dauer larval diapause and its associated adult phenotypes in the nematode (Caenorhabditis elegans), reproductive dormancy in the fruit fly (Drosophila melanogaster) and other insects, and the worker castes of the honey bee (Apis mellifera) are examples of what may be viewed as the polyphenic regulation of somatic maintenance and survival. In these and other cases, the same genotype can--depending upon its environment--express either of two alternative sets of life-history phenotypes that differ markedly with respect to somatic maintenance, survival ability, and thus life span. This plastic modulation of somatic maintenance and survival has traditionally been underappreciated by researchers working on aging and life history. We review the current evidence for such adaptive life-history switches and their molecular regulation and suggest that they are caused by temporally and/or spatially varying, stressful environments that impose diversifying selection, thereby favoring the evolution of plasticity of somatic maintenance and survival under strong regulatory control. By considering somatic maintenance and survivorship from the perspective of adaptive life-history switches, we may gain novel insights into the mechanisms and evolution of aging.
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Affiliation(s)
- Thomas Flatt
- Institut für Populationsgenetik, Vetmeduni Vienna, A-1210 Vienna, Austria.
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Fay DS. Cancer metabolism: feeding a worm to starve a tumor. Curr Biol 2013; 23:R557-9. [PMID: 23845240 DOI: 10.1016/j.cub.2013.05.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The tumor suppressor Rb is known to have its hand in many pots. New findings have added another pot to the mix - cell metabolism. This may lead to a better understanding of Rb mutant phenotypes and Rb's roles in oncogenesis.
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Affiliation(s)
- David S Fay
- Department of Molecular Biology, College of Agriculture and Natural Resources, University of Wyoming, Laramie, WY 82071, USA.
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Chandra A, van Maldegem F, Andrews S, Neuberger MS, Rada C. Deficiency in spliceosome-associated factor CTNNBL1 does not affect ongoing cell cycling but delays exit from quiescence and results in embryonic lethality in mice. Cell Cycle 2013; 12:732-42. [PMID: 23343763 PMCID: PMC3610721 DOI: 10.4161/cc.23594] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
CTNNBL1 is an armadillo-repeat protein that associates with the CDC5L/Prp19 complex of the spliceosome. Unlike the majority of spliceosomal proteins (and despite having no obvious homologs), CTNNBL1 is inessential for cell viability as revealed by studies in both vertebrate B cell lines and in fission yeast. Here, however, we show that ablation of CTNNBL1 in the mouse germline results in mid-gestation embryonic lethality but that lineage-specific CTNNBL1 ablation in early B cell precursors does not affect the production and abundance of mature B lymphocytes. However, CTNNBL1-deficient resting B lymphocytes show sluggish exit from quiescence on cell activation, although once entry into cycle has initiated, proliferation and differentiation in response to mitogenic stimuli continue largely unaffected. A similar sluggish exit from quiescence is also observed on reprovision of nutrients to nitrogen-starved CTNNBL1-deficient yeast. The results indicate that, whereas other RNA splicing-associated factors have been connected to cell cycle progression, CTNNBL1 plays no essential role in cycling cells but does fulfill an evolutionarily conserved function in helping cells to undergo efficient exit from quiescence following activation.
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Affiliation(s)
- Anita Chandra
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
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Garcia AM, Ladage ML, Padilla PA. Use of time lapse microscopy to visualize anoxia-induced suspended animation in C. elegans embryos. J Vis Exp 2012:e4319. [PMID: 23242305 DOI: 10.3791/4319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Caenorhabdits elegans has been used extensively in the study of stress resistance, which is facilitated by the transparency of the adult and embryo stages as well as by the availability of genetic mutants and transgenic strains expressing a myriad of fusion proteins(1-4). In addition, dynamic processes such as cell division can be viewed using fluorescently labeled reporter proteins. The study of mitosis can be facilitated through the use of time-lapse experiments in various systems including intact organisms; thus the early C. elegans embryo is well suited for this study. Presented here is a technique by which in vivo imaging of sub-cellular structures in response to anoxic (99.999% N2; <2 ppm O2) stress is possible using a simple gas flow through setup on a high-powered microscope. A microincubation chamber is used in conjunction with nitrogen gas flow through and a spinning disc confocal microscope to create a controlled environment in which animals can be imaged in vivo. Using GFP-tagged gamma tubulin and histone, the dynamics and arrest of cell division can be monitored before, during and after exposure to an oxygen-deprived environment. The results of this technique are high resolution, detailed videos and images of cellular structures within blastomeres of embryos exposed to oxygen deprivation.
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Iranon NN, Miller DL. Interactions between oxygen homeostasis, food availability, and hydrogen sulfide signaling. Front Genet 2012; 3:257. [PMID: 23233860 PMCID: PMC3516179 DOI: 10.3389/fgene.2012.00257] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 11/04/2012] [Indexed: 12/19/2022] Open
Abstract
The ability to sense and respond to stressful conditions is essential to maintain organismal homeostasis. It has long been recognized that stress response factors that improve survival in changing conditions can also influence longevity. In this review, we discuss different strategies used by animals in response to decreased O(2) (hypoxia) to maintain O(2) homeostasis, and consider interactions between hypoxia responses, nutritional status, and H(2)S signaling. O(2) is an essential environmental nutrient for almost all metazoans as it plays a fundamental role in development and cellular metabolism. However, the physiological response(s) to hypoxia depend greatly on the amount of O(2) available. Animals must sense declining O(2) availability to coordinate fundamental metabolic and signaling pathways. It is not surprising that factors involved in the response to hypoxia are also involved in responding to other key environmental signals, particularly food availability. Recent studies in mammals have also shown that the small gaseous signaling molecule hydrogen sulfide (H(2)S) protects against cellular damage and death in hypoxia. These results suggest that H(2)S signaling also integrates with hypoxia response(s). Many of the signaling pathways that mediate the effects of hypoxia, food deprivation, and H(2)S signaling have also been implicated in the control of lifespan. Understanding how these pathways are coordinated therefore has the potential to reveal new cellular and organismal homeostatic mechanisms that contribute to longevity assurance in animals.
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Affiliation(s)
- Nicole N Iranon
- Department of Biochemistry, University of Washington School of Medicine Seattle, WA, USA ; Molecular and Cellular Biology Graduate Program, University of Washington School of Medicine Seattle, WA, USA
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