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Dolfi L, Suen TK, Medelbekova D, Ripa R, Symmons O, Antebi A. In Vitro Fertilization of the African Turquoise Killifish Nothobranchius furzeri. Cold Spring Harb Protoc 2023; 2023:107886. [PMID: 37100471 DOI: 10.1101/pdb.prot107886] [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: 04/28/2023]
Abstract
The ability to perform in vitro fertilization, together with sperm cryopreservation, greatly facilitates the long-term laboratory maintenance of wild-type and transgenic model organisms and helps prevent genetic drift. It is also useful in cases where reproduction may be compromised. In this protocol, we present a method for in vitro fertilization of the African Turquoise killifish Nothobranchius furzeri that is compatible with the use of fresh or cryopreserved sperm.
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Affiliation(s)
- Luca Dolfi
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Tsz Kin Suen
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | | | - Roberto Ripa
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Orsolya Symmons
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Adam Antebi
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
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Teefy BB, Adler A, Xu A, Hsu K, Singh PP, Benayoun BA. Dynamic regulation of gonadal transposon control across the lifespan of the naturally short-lived African turquoise killifish. Genome Res 2023; 33:141-153. [PMID: 36577520 PMCID: PMC9977155 DOI: 10.1101/gr.277301.122] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022]
Abstract
Although germline cells are considered to be functionally "immortal," both the germline and supporting somatic cells in the gonad within an organism experience aging. With increased age at parenthood, the age-related decline in reproductive success has become an important biological issue for an aging population. However, molecular mechanisms underlying reproductive aging across sexes in vertebrates remain poorly understood. To decipher molecular drivers of vertebrate gonadal aging across sexes, we perform longitudinal characterization of the gonadal transcriptome throughout the lifespan in the naturally short-lived African turquoise killifish (Nothobranchius furzeri). By combining mRNA-seq and small RNA-seq from 26 individuals, we characterize the aging gonads of young-adult, middle-aged, and old female and male fish. We analyze changes in transcriptional patterns of genes, transposable elements (TEs), and piRNAs. We find that testes seem to undergo only marginal changes during aging. In contrast, in middle-aged ovaries, the time point associated with peak female fertility in this strain, PIWI pathway components are transiently down-regulated, TE transcription is elevated, and piRNA levels generally decrease, suggesting that egg quality may already be declining at middle-age. Furthermore, we show that piRNA ping-pong biogenesis declines steadily with age in ovaries, whereas it is maintained in aging testes. To our knowledge, this data set represents the most comprehensive transcriptomic data set for vertebrate gonadal aging. This resource also highlights important pathways that are regulated during reproductive aging in either ovaries or testes, which could ultimately be leveraged to help restore aspects of youthful reproductive function.
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Affiliation(s)
- Bryan B Teefy
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California 90089, USA
| | - Ari Adler
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California 90089, USA
| | - Alan Xu
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California 90089, USA.,Molecular and Computational Biology Department, USC Dornsife College of Letters, Arts and Sciences, Los Angeles, California 90089, USA
| | - Katelyn Hsu
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California 90089, USA.,Molecular and Computational Biology Department, USC Dornsife College of Letters, Arts and Sciences, Los Angeles, California 90089, USA
| | - Param Priya Singh
- Department of Genetics, Stanford University, Stanford, California 94305, USA
| | - Bérénice A Benayoun
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California 90089, USA.,Molecular and Computational Biology Department, USC Dornsife College of Letters, Arts and Sciences, Los Angeles, California 90089, USA.,Biochemistry and Molecular Medicine Department, USC Keck School of Medicine, Los Angeles, California 90089, USA.,USC Norris Comprehensive Cancer Center, Epigenetics and Gene Regulation, Los Angeles, California 90089, USA.,USC Stem Cell Initiative, Los Angeles, California 90089, USA
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McKay A, Costa EK, Chen J, Hu CK, Chen X, Bedbrook CN, Khondker RC, Thielvoldt M, Priya Singh P, Wyss-Coray T, Brunet A. An automated feeding system for the African killifish reveals the impact of diet on lifespan and allows scalable assessment of associative learning. eLife 2022; 11:e69008. [PMID: 36354233 PMCID: PMC9788828 DOI: 10.7554/elife.69008] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 11/09/2022] [Indexed: 11/11/2022] Open
Abstract
The African turquoise killifish is an exciting new vertebrate model for aging studies. A significant challenge for any model organism is the control over its diet in space and time. To address this challenge, we created an automated and networked fish feeding system. Our automated feeder is designed to be open-source, easily transferable, and built from widely available components. Compared to manual feeding, our automated system is highly precise and flexible. As a proof of concept for the feeding flexibility of these automated feeders, we define a favorable regimen for growth and fertility for the African killifish and a dietary restriction regimen where both feeding time and quantity are reduced. We show that this dietary restriction regimen extends lifespan in males (but not in females) and impacts the transcriptomes of killifish livers in a sex-specific manner. Moreover, combining our automated feeding system with a video camera, we establish a quantitative associative learning assay to provide an integrative measure of cognitive performance for the killifish. The ability to precisely control food delivery in the killifish opens new areas to assess lifespan and cognitive behavior dynamics and to screen for dietary interventions and drugs in a scalable manner previously impossible with traditional vertebrate model organisms.
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Affiliation(s)
- Andrew McKay
- Department of Genetics, Stanford UniversityStanfordUnited States
- Biology Graduate Program, Stanford UniversityStanfordUnited States
| | - Emma K Costa
- Department of Neurology and Neurological Sciences, Stanford UniversityStanfordUnited States
- Neurosciences Interdepartmental Program, Stanford University School of MedicineStanfordUnited States
| | - Jingxun Chen
- Department of Genetics, Stanford UniversityStanfordUnited States
| | - Chi-Kuo Hu
- Department of Genetics, Stanford UniversityStanfordUnited States
| | - Xiaoshan Chen
- Department of Genetics, Stanford UniversityStanfordUnited States
| | - Claire N Bedbrook
- Department of Genetics, Stanford UniversityStanfordUnited States
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | | | | | | | - Tony Wyss-Coray
- Department of Neurology and Neurological Sciences, Stanford UniversityStanfordUnited States
- Glenn Laboratories for the Biology of Aging, Stanford UniversityStanfordUnited States
- Wu Tsai Neurosciences Institute, Stanford UniversityStanfordUnited States
| | - Anne Brunet
- Department of Genetics, Stanford UniversityStanfordUnited States
- Glenn Laboratories for the Biology of Aging, Stanford UniversityStanfordUnited States
- Wu Tsai Neurosciences Institute, Stanford UniversityStanfordUnited States
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Sperm cryopreservation and in vitro fertilization techniques for the African turquoise killifish Nothobranchius furzeri. Sci Rep 2021; 11:17145. [PMID: 34433853 PMCID: PMC8387425 DOI: 10.1038/s41598-021-96383-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 08/05/2021] [Indexed: 11/23/2022] Open
Abstract
Over the last decade, the African turquoise killifish, Nothobranchius furzeri, has emerged as an important model system for the study of vertebrate biology and ageing. Propagation of laboratory inbred strains of Nothobranchius furzeri, such as GRZ, however, can pose challenges due to the short window of fertility, the efforts and space requirements involved in continuous strain maintenance, and the risks of further inbreeding. The current method for long term strain preservation relies on arrest of embryos in diapause. To create an alternative for long term maintenance, we developed a robust protocol to cryopreserve and revive sperm for in vitro fertilization (IVF). We tested a variety of extender and activator buffers for sperm IVF, as well as cryoprotectants to achieve practical long-term storage and fertilization conditions tailored to this species. Our protocol enabled sperm to be preserved in a cryogenic condition for months and to be revived with an average of 40% viability upon thawing. Thawed sperm were able to fertilize nearly the same number of eggs as natural fertilization, with an average of ~ 25% and peaks of ~ 55% fertilization. This technical advance will greatly facilitate the use of N. furzeri as a model organism.
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Baghdadi M, Hinterding HM, Partridge L, Deelen J. From mutation to mechanism: deciphering the molecular function of genetic variants linked to human ageing. Brief Funct Genomics 2021; 21:13-23. [PMID: 33690799 PMCID: PMC8789301 DOI: 10.1093/bfgp/elab005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 01/20/2023] Open
Abstract
Many of the leading causes of death in humans, such as cardiovascular disease, type 2 diabetes and Alzheimer’s disease are influenced by biological mechanisms that become dysregulated with increasing age. Hence, by targeting these ageing-related mechanisms, we may be able to improve health in old age. Ageing is partly heritable and genetic studies have been moderately successful in identifying genetic variants associated with ageing-related phenotypes (lifespan, healthspan and longevity). To decipher the mechanisms by which the identified variants influence ageing, studies that focus on their functional validation are vital. In this perspective, we describe the steps that could be taken in the process of functional validation: (1) in silico characterisation using bioinformatic tools; (2) in vitro characterisation using cell lines or organoids; and (3) in vivo characterisation studies using model organisms. For the in vivo characterisation, it is important to focus on translational phenotypes that are indicative of both healthspan and lifespan, such as the frailty index, to inform subsequent intervention studies. The depth of functional validation of a genetic variant depends on its location in the genome and conservation in model organisms. Moreover, some variants may prove to be hard to characterise due to context-dependent effects related to the experimental environment or genetic background. Future efforts to functionally characterise the (newly) identified genetic variants should shed light on the mechanisms underlying ageing and will help in the design of targeted interventions to improve health in old age.
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Randazzo B, Zarantoniello M, Cardinaletti G, Cerri R, Giorgini E, Belloni A, Contò M, Tibaldi E, Olivotto I. Hermetia illucens and Poultry by-Product Meals as Alternatives to Plant Protein Sources in Gilthead Seabream ( Sparus aurata) Diet: A Multidisciplinary Study on Fish Gut Status. Animals (Basel) 2021; 11:ani11030677. [PMID: 33806710 PMCID: PMC8001786 DOI: 10.3390/ani11030677] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 12/15/2022] Open
Abstract
Simple Summary Sustainability and fish welfare have been receiving increasing attention in the aquaculture sector, with an emphasis on the search for new, sustainable, and healthy aquafeed ingredients. For many years, plant ingredients have been widely used in aquafeed formulation; however, negative side effects on gut welfare have often been reported in several carnivorous fish species. From this perspective, alternative ingredients such as poultry by-products and insect meal are receiving attention due to their low ecological footprint and high nutritional value. In the present study, these two ingredients were used, singly or in combination, to formulate practical diets for gilthead seabream (Sparus aurata). After a twelve-week feeding trial, a multidisciplinary laboratory approach including histological, molecular, and spectroscopic techniques was adopted in order to investigate fish physiological responses to the new test diets. The results obtained showed excellent zootechnical performances and ameliorated gut health in fish fed dietary inclusions of poultry by-products and insect meal compared to those fed a vegetable-based diet. In addition, the modulation of nutrient absorption in relation to the ingredients used was highlighted by means of spectroscopic tools. The results obtained demonstrated that poultry by-products and insect meal can be successfully used to replace plant-derived ingredients in diets for gilthead seabream without negatively affecting fish welfare. Abstract The attempt to replace marine-derived ingredients for aquafeed formulation with plant-derived ones has met some limitations due to their negative side effects on many fish species. In this context, finding new, sustainable ingredients able to promote fish welfare is currently under exploration. In the present study, poultry by-products and Hermetia illucens meal were used to replace the vegetable protein fraction in diets totally deprived of fish meal intended for gilthead seabream (Sparus aurata). After a 12-week feeding trial, a multidisciplinary approach including histological, molecular, and spectroscopic techniques was adopted to investigate intestine and liver responses to the different dietary formulations. Regardless of the alternative ingredient used, the reduction in dietary vegetable proteins resulted in a lower incidence of intestine histological alterations and inflammatory responses. In addition, the dietary inclusion of insect meal positively affected the reduction in the molecular inflammatory markers analyzed. Spectroscopic analyses showed that poultry by-product meal improved lipid absorption in the intestine, while insect meal induced increased liver lipid deposition in fish. The results obtained demonstrated that both poultry by-products and H. illucens meal can successfully be used to replace plant-derived ingredients in diets for gilthead seabream, promoting healthy aquaculture.
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Affiliation(s)
- Basilio Randazzo
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy; (B.R.); (M.Z.); (E.G.); (A.B.)
| | - Matteo Zarantoniello
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy; (B.R.); (M.Z.); (E.G.); (A.B.)
| | - Gloriana Cardinaletti
- Department of Agricultural, Food, Environmental and Animal Science, University of Udine, 33100 Udine, Italy; (G.C.); (R.C.); (E.T.)
| | - Roberto Cerri
- Department of Agricultural, Food, Environmental and Animal Science, University of Udine, 33100 Udine, Italy; (G.C.); (R.C.); (E.T.)
| | - Elisabetta Giorgini
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy; (B.R.); (M.Z.); (E.G.); (A.B.)
| | - Alessia Belloni
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy; (B.R.); (M.Z.); (E.G.); (A.B.)
| | - Michela Contò
- Council for Agricultural Research and Analysis of Agricultural Economics (CREA), Research Centre for Animal Production and Aquaculture, 00015 Rome, Italy;
| | - Emilio Tibaldi
- Department of Agricultural, Food, Environmental and Animal Science, University of Udine, 33100 Udine, Italy; (G.C.); (R.C.); (E.T.)
| | - Ike Olivotto
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy; (B.R.); (M.Z.); (E.G.); (A.B.)
- Correspondence:
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