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Chao CF, Pesch YY, Yu H, Wang C, Aristizabal MJ, Huan T, Tanentzapf G, Rideout E. An important role for triglyceride in regulating spermatogenesis. eLife 2024; 12:RP87523. [PMID: 38805376 PMCID: PMC11132686 DOI: 10.7554/elife.87523] [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] [Indexed: 05/30/2024] Open
Abstract
Drosophila is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid droplets (LD), to sperm development is largely unknown. Emerging evidence suggests LD are present in the testis and that loss of neutral lipid- and LD-associated genes causes subfertility; however, key regulators of testis neutral lipids and LD remain unclear. Here, we show LD are present in early-stage somatic and germline cells within the Drosophila testis. We identified a role for triglyceride lipase brummer (bmm) in regulating testis LD, and found that whole-body loss of bmm leads to defects in sperm development. Importantly, these represent cell-autonomous roles for bmm in regulating testis LD and spermatogenesis. Because lipidomic analysis of bmm mutants revealed excess triglyceride accumulation, and spermatogenic defects in bmm mutants were rescued by genetically blocking triglyceride synthesis, our data suggest that bmm-mediated regulation of triglyceride influences sperm development. This identifies triglyceride as an important neutral lipid that contributes to Drosophila sperm development, and reveals a key role for bmm in regulating testis triglyceride levels during spermatogenesis.
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Affiliation(s)
- Charlotte F Chao
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Yanina-Yasmin Pesch
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Huaxu Yu
- Department of Chemistry, The University of British ColumbiaVancouverCanada
| | - Chenjingyi Wang
- Department of Chemistry, The University of British ColumbiaVancouverCanada
| | | | - Tao Huan
- Department of Chemistry, The University of British ColumbiaVancouverCanada
| | - Guy Tanentzapf
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
| | - Elizabeth Rideout
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British ColumbiaVancouverCanada
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Li X, Weth O, Haimann M, Möscheid MF, Huber TS, Grevelding CG. Rhodopsin orphan GPCR20 interacts with neuropeptides and directs growth, sexual differentiation, and egg production in female Schistosoma mansoni. Microbiol Spectr 2024; 12:e0219323. [PMID: 38047698 PMCID: PMC10783048 DOI: 10.1128/spectrum.02193-23] [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: 05/24/2023] [Accepted: 10/17/2023] [Indexed: 12/05/2023] Open
Abstract
IMPORTANCE Schistosomes cause schistosomiasis, one of the neglected tropical diseases as defined by the WHO. For decades, the treatment of schistosomiasis relies on a single drug, praziquantel. Due to its wide use, there is justified fear of resistance against this drug, and a vaccine is not available. Besides its biological relevance in signal transduction processes, the class of G protein-coupled receptors (GPCRs) is also well suited for drug design. Against this background, we characterized one GPCR of Schistosoma mansoni, SmGPCR20, at the molecular and functional level. We identified two potential neuropeptides (NPPs) as ligands, SmNPP26 and SmNPP40, and unraveled their roles, in combination with SmGPCR20, in neuronal processes controlling egg production, oogenesis, and growth of S. mansoni females. Since eggs are closely associated with the pathogenesis of schistosomiasis, our results contribute to the understanding of processes leading to egg production in schistosomes, which is under the control of pairing in this exceptional parasite.
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Affiliation(s)
- Xuesong Li
- Institute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
| | - Oliver Weth
- Institute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
| | - Martin Haimann
- Institute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
| | - Max F. Möscheid
- Institute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
| | - Theresa S. Huber
- Institute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
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Seth RK, Yadav P, Reynolds SE. Dichotomous sperm in Lepidopteran insects: a biorational target for pest management. FRONTIERS IN INSECT SCIENCE 2023; 3:1198252. [PMID: 38469506 PMCID: PMC10926456 DOI: 10.3389/finsc.2023.1198252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/31/2023] [Indexed: 03/13/2024]
Abstract
Lepidoptera are unusual in possessing two distinct kinds of sperm, regular nucleated (eupyrene) sperm and anucleate (apyrene) sperm ('parasperm'). Sperm of both types are transferred to the female and are required for male fertility. Apyrene sperm play 'helper' roles, assisting eupyrene sperm to gain access to unfertilized eggs and influencing the reproductive behavior of mated female moths. Sperm development and behavior are promising targets for environmentally safer, target-specific biorational control strategies in lepidopteran pest insects. Sperm dimorphism provides a wide window in which to manipulate sperm functionality and dynamics, thereby impairing the reproductive fitness of pest species. Opportunities to interfere with spermatozoa are available not only while sperm are still in the male (before copulation), but also in the female (after copulation, when sperm are still in the male-provided spermatophore, or during storage in the female's spermatheca). Biomolecular technologies like RNAi, miRNAs and CRISPR-Cas9 are promising strategies to achieve lepidopteran pest control by targeting genes directly or indirectly involved in dichotomous sperm production, function, or persistence.
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Affiliation(s)
- Rakesh K. Seth
- Department of Zoology, University of Delhi, Delhi, India
| | - Priya Yadav
- Department of Zoology, University of Delhi, Delhi, India
| | - Stuart E. Reynolds
- Department of Life Sciences, University of Bath, Bath, United Kingdom
- Milner Centre for Evolution, University of Bath, Bath, United Kingdom
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4
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Estêvão J, Osorio H, Costas B, Cruz A, Fernández-Boo S. Search for new biomarkers of tolerance to Perkinsus olseni parasite infection in Ruditapes decussatus clams. FISH & SHELLFISH IMMUNOLOGY 2023; 134:108566. [PMID: 36736640 DOI: 10.1016/j.fsi.2023.108566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/23/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
The grooved carpet shell (Ruditapes decussatus) is a clam species with high economic and social importance in several European and Mediterranean countries. Production of this species suffered a decline caused by biotic (parasite infection) and abiotic factors (environmental factors, stress, poor management methods and intensive culture of the introduced species Ruditapes philippinarum). The protozoan parasite Perkinsus olseni is also responsible for the decline of production, being nowadays one of the major issues for clam culture. Molecular biomarkers that might represent tolerance of R. decussatus to P. olseni have already been uncovered, shedding light in a possible production improvement by selecting those clams with a strongest immune response. In the present study, new tolerance biomarkers to P. olseni infection in R. decussatus were identified. The haemolymph proteomic profiles of naturally non/low-infected (tolerant) and highly-infected (susceptible) clams by the parasite across several heavy affected areas of Europe were characterized through a shotgun proteomics approach. Also, the mechanisms that might be involved in the responses against the disease in chronic infections were explored. Proteins related to energy restoration and balance, metabolic regulation, energy accumulation, ROS production, lysosomal activity, amino acid synthesis, proteolytic activity, iron regulation, iron withholding, and immune response modulation were significantly regulated in susceptible clams. In the tolerant group, proteins related to phagocytosis regulation, control of cell growth and proliferation, gonadal maturation, regulation of apoptosis, growth modulation, response to oxidative stress, iron regulation, shell development and metabolic regulation were significantly expressed. In summary, the protein expression profile of tolerant individuals suggests that an efficient pathogen elimination mechanism coupled to a better metabolic regulation leads to a tolerance to the parasite infection by limiting the spread through the tissues.
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Affiliation(s)
- João Estêvão
- Animal Health and Aquaculture (A2S), CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, University of Porto, Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Hugo Osorio
- i3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal; Ipatimup-Institute of Molecular Pathology and Immunology of the University of Porto, University of Porto, Porto, Portugal
| | - Benjamin Costas
- Animal Health and Aquaculture (A2S), CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, University of Porto, Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Andreia Cruz
- Oceano Fresco S.A, Porto de Abrigo, 2450-075, Nazaré, Portugal
| | - Sergio Fernández-Boo
- Animal Health and Aquaculture (A2S), CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, University of Porto, Porto, Portugal.
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5
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Yoon S, Shin M, Shim J. Inter-organ regulation by the brain in Drosophila development and physiology. J Neurogenet 2022:1-13. [DOI: 10.1080/01677063.2022.2137162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Sunggyu Yoon
- Department of Life Sciences, College of Natural Science, Hanyang University, Seoul, Republic of Korea
| | - Mingyu Shin
- Department of Life Sciences, College of Natural Science, Hanyang University, Seoul, Republic of Korea
| | - Jiwon Shim
- Department of Life Sciences, College of Natural Science, Hanyang University, Seoul, Republic of Korea
- Research Institute for Natural Science, Hanyang University, Seoul, Republic of Korea
- Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul, Republic of Korea
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6
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Tian Y, Sun P, Liu WX, Shan LY, Hu YT, Fan HT, Shen W, Liu YB, Zhou Y, Zhang T. Single-cell RNA sequencing of the Mongolia sheep testis reveals a conserved and divergent transcriptome landscape of mammalian spermatogenesis. FASEB J 2022; 36:e22348. [PMID: 35583907 DOI: 10.1096/fj.202200152r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/09/2022] [Accepted: 05/02/2022] [Indexed: 12/12/2022]
Abstract
Spermatogenesis is a highly coordinated and complex process, and is pivotal for transmitting genetic information between mammalian generations. In this study, we investigated the conservation, differences, and biological functions of homologous genes during spermatogenesis in Mongolia sheep, humans, cynomolgus monkey, and mice using single-cell RNA sequencing technology. We compared X chromosome meiotic inactivation events in Mongolia sheep, humans, cynomolgus monkey, and mice to uncover the concerted activity of X chromosome genes. Subsequently, we focused on the dynamics of gene expression, key biological functions, and signaling pathways at various stages of spermatogenesis in Mongolia sheep and humans. Additionally, the ligand-receptor networks of Mongolia sheep and humans in testicular somatic and germ cells at different developmental stages were mapped to reveal conserved germ cell-soma communication using single-cell resolution. These datasets provided novel information and insights to unravel the molecular regulatory mechanisms of Mongolia sheep spermatogenesis and highlight conservation in gene expression during spermatogenesis between Mongolia sheep and humans, providing a foundation for the establishment of a large mammalian disease model of male infertility.
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Affiliation(s)
- Yu Tian
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Peng Sun
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China.,Laboratory of Microbiology and Immunology, College of Basic Medicine, Inner Mongolia Medical University, Hohhot, China
| | - Wen-Xiang Liu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Li-Ying Shan
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Yan-Ting Hu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Hai-Tao Fan
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Wei Shen
- College of Life Sciences, Institute of Reproductive Sciences, Qingdao Agricultural University, Qingdao, China
| | - Yong-Bin Liu
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China.,Animal Husbandry Institute, Inner Mongolia Academy of Agricultural & Animal Husbandry Sciences, Hohhot, China
| | - Yang Zhou
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Teng Zhang
- State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock (R2BGL), College of Life Sciences, Inner Mongolia University, Hohhot, China
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Al Baki MA, Kyo Jung J, Kim Y. Physiological Alterations in Deletion Mutants of Two Insulin-Like Peptides Encoded in Maruca vitrata Using CRISPR/Cas9. Front Physiol 2021; 12:701616. [PMID: 34276424 PMCID: PMC8284963 DOI: 10.3389/fphys.2021.701616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/09/2021] [Indexed: 11/15/2022] Open
Abstract
Most insect species encode multiple insulin-like peptides (ILPs) that exhibit functional overlaps in mediating physiological processes such as development and reproduction. Why do they need multiple ILPs? To address this question, we tested a hypothesis of the requirement of multiple ILPs by generating mutants lacking individual ILP genes using the CRISPR/Cas9 technology. Two ILPs (ILP1 and ILP2) in the legume pod borer, Maruca vitrata, mediate similar physiological processes such as hemolymph sugar level, larval development, and adult reproduction. Individual knock-out mutants (ΔILP1 and ΔILP2) were generated. They showed successful development from larvae to adults. However, they suffered from high hemolymph sugar levels by enhancing trehalose titers in the hemolymph. The hyperglycemic effect was more evident in ΔILP2 mutants than in ΔILP1 mutants. Both mutants showed increased expression of trehalose-6-phosphate synthase but suppressed expression of trehalase. These mutants also showed altered expression patterns of insulin signaling components. Expression levels of insulin receptor and Akt genes were upregulated, while those of FOXO and Target of rapamycin genes were downregulated in these mutants. These alterations of signal components resulted in significant retardation of immature development and reduced body sizes. ΔILP1 or ΔILP2 females exhibited poor oocyte development. Bromo-uridine incorporation was much reduced at the germarium of ovarioles of these mutants compared with wild females. Expression of the vitellogenin gene was also reduced in these mutants. Furthermore, males of these deletion mutants showed impaired reproductive activities when they mated with wild-type females. These results suggest that both ILPs are required for mediating larval development and adult reproduction in M. vitrata.
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Affiliation(s)
| | - Jin Kyo Jung
- Division of Crop Cultivation and Environment Research, Department of Central Area Crop Science, National Institute of Crop Science, Rural Development Administration, Suwon, South Korea
| | - Yonggyun Kim
- Department of Plant Medicals, Andong National University, Andong, South Korea
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8
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Chowański S, Walkowiak-Nowicka K, Winkiel M, Marciniak P, Urbański A, Pacholska-Bogalska J. Insulin-Like Peptides and Cross-Talk With Other Factors in the Regulation of Insect Metabolism. Front Physiol 2021; 12:701203. [PMID: 34267679 PMCID: PMC8276055 DOI: 10.3389/fphys.2021.701203] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/04/2021] [Indexed: 02/06/2023] Open
Abstract
The insulin-like peptide (ILP) and insulin-like growth factor (IGF) signalling pathways play a crucial role in the regulation of metabolism, growth and development, fecundity, stress resistance, and lifespan. ILPs are encoded by multigene families that are expressed in nervous and non-nervous organs, including the midgut, salivary glands, and fat body, in a tissue- and stage-specific manner. Thus, more multidirectional and more complex control of insect metabolism can occur. ILPs are not the only factors that regulate metabolism. ILPs interact in many cross-talk interactions of different factors, for example, hormones (peptide and nonpeptide), neurotransmitters and growth factors. These interactions are observed at different levels, and three interactions appear to be the most prominent/significant: (1) coinfluence of ILPs and other factors on the same target cells, (2) influence of ILPs on synthesis/secretion of other factors regulating metabolism, and (3) regulation of activity of cells producing/secreting ILPs by various factors. For example, brain insulin-producing cells co-express sulfakinins (SKs), which are cholecystokinin-like peptides, another key regulator of metabolism, and express receptors for tachykinin-related peptides, the next peptide hormones involved in the control of metabolism. It was also shown that ILPs in Drosophila melanogaster can directly and indirectly regulate AKH. This review presents an overview of the regulatory role of insulin-like peptides in insect metabolism and how these factors interact with other players involved in its regulation.
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Affiliation(s)
- Szymon Chowański
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Karolina Walkowiak-Nowicka
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Magdalena Winkiel
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Pawel Marciniak
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Arkadiusz Urbański
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland.,HiProMine S.A., Robakowo, Poland
| | - Joanna Pacholska-Bogalska
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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9
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Azuma M, Ogata T, Yamazoe K, Tanaka Y, Inoue YH. Heat shock cognate 70 genes contribute to Drosophila spermatocyte growth progression possibly through the insulin signaling pathway. Dev Growth Differ 2021; 63:231-248. [PMID: 34050930 DOI: 10.1111/dgd.12734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 04/27/2021] [Accepted: 04/27/2021] [Indexed: 11/28/2022]
Abstract
Drosophila spermatocytes grow up to 25 times their original volume before the onset of male meiosis. Several insulin-like peptides and their cognate receptors (InR) are essential for the cell growth process in Drosophila. Here, we aimed to identify additional signaling pathways and other regulatory factors required for germline cell growth in Drosophila males. Spermatocyte-specific expression of the dominant-negative form of InR inhibits cell growth. Conversely, constitutively active forms of signaling factors downstream of InR suppress growth inhibition. Furthermore, hypomorphic mutations in the target of rapamycin (Tor) inhibit spermatocyte growth. These data indicate that the insulin/TOR pathway is essential for the growth of premeiotic spermatocytes. RNA interference (RNAi) screening for the identification of other novel genes associated with cell growth showed that the silencing of each of the five members of heat shock cognate 70 (Hsc70) genes significantly inhibited the process. Hsc70-silenced spermatocytes showed Akt inhibition downstream of the insulin signaling pathway. Our pleckstrin homology domain-green fluorescent protein (PH-GFP) reporter studies indicated that PI3K remained activated in Hsc70-4-silenced cells, suggesting that the Hsc70-4 protein possibly targets Akt or Pdk1 acting downstream of PI3K. Moreover, each of the Hsc70 proteins showed different subcellular localizations. Hsc70-2 exhibited cytoplasmic colocalization with Akt in spermatocytes before nuclear entry of the kinase during the growth phase. These results indicated the involvement of Hsc70 proteins in the activation of various steps in the insulin signaling pathway, which is essential for spermatocyte growth. Our findings provide insights into the mechanism(s) that enhance signal transduction to stimulate the growth of Drosophila spermatocytes.
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Affiliation(s)
- Maho Azuma
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Kyoto, Japan
| | - Tsubasa Ogata
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Kyoto, Japan
| | - Kanta Yamazoe
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Kyoto, Japan
| | - Yuri Tanaka
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Kyoto, Japan
| | - Yoshihiro H Inoue
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Kyoto, Japan
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10
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Marca JEL, Somers WG. The Drosophila gonads: models for stem cell proliferation, self-renewal, and differentiation. AIMS GENETICS 2021. [DOI: 10.3934/genet.2014.1.55] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AbstractThe male and female gonads of Drosophila melanogaster have developed into powerful model systems for both the study of stem cell behaviours, and for understanding how stem cell misregulation can lead to cancers. Using these systems, one is able to observe and manipulate the resident stem cell populations in vivo with a great deal of licence. The tractability of the testis and ovary also allow researchers to explore a range of cellular mechanisms, such as proliferation and polarity, as well as the influence exerted by the local environment through a host of highly-conserved signalling pathways. Importantly, many of the cellular behaviours and processes studied in the Drosophila testis and ovary are known to be disrupted, or otherwise misregulated, in human tumourigenic cells. Here, we review the mechanisms relating to stem cell behaviour, though we acknowledge there are many other fascinating aspects of gametogenesis, including the invasive behaviour of migratory border cells in the Drosophila ovary that, though relevant to the study of tumourigenesis, will unfortunately not be covered.
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Affiliation(s)
- John E. La Marca
- Department of Genetics, La Trobe University, Melbourne, VIC 3086, Australia
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11
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Millington JW, Brownrigg GP, Basner-Collins PJ, Sun Z, Rideout EJ. Genetic manipulation of insulin/insulin-like growth factor signaling pathway activity has sex-biased effects on Drosophila body size. G3 (BETHESDA, MD.) 2021; 11:jkaa067. [PMID: 33793746 PMCID: PMC8063079 DOI: 10.1093/g3journal/jkaa067] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 11/09/2020] [Indexed: 12/14/2022]
Abstract
In Drosophila raised in nutrient-rich conditions, female body size is approximately 30% larger than male body size due to an increased rate of growth and differential weight loss during the larval period. While the mechanisms that control this sex difference in body size remain incompletely understood, recent studies suggest that the insulin/insulin-like growth factor signaling pathway (IIS) plays a role in the sex-specific regulation of processes that influence body size during development. In larvae, IIS activity differs between the sexes, and there is evidence of sex-specific regulation of IIS ligands. Yet, we lack knowledge of how changes to IIS activity impact body size in each sex, as the majority of studies on IIS and body size use single- or mixed-sex groups of larvae and/or adult flies. The goal of our current study was to clarify the body size requirement for IIS activity in each sex. To achieve this goal, we used established genetic approaches to enhance, or inhibit, IIS activity, and quantified pupal size in males and females. Overall, genotypes that inhibited IIS activity caused a female-biased decrease in body size, whereas genotypes that augmented IIS activity caused a male-specific increase in body size. These data extend our current understanding of body size regulation by showing that most changes to IIS pathway activity have sex-biased effects, and highlights the importance of analyzing body size data according to sex.
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Affiliation(s)
- Jason W Millington
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - George P Brownrigg
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Paige J Basner-Collins
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Ziwei Sun
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Elizabeth J Rideout
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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12
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Molecular basis of reproductive senescence: insights from model organisms. J Assist Reprod Genet 2020; 38:17-32. [PMID: 33006069 DOI: 10.1007/s10815-020-01959-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 09/25/2020] [Indexed: 12/14/2022] Open
Abstract
PURPOSE Reproductive decline due to parental age has become a major barrier to fertility as couples have delayed having offspring into their thirties and forties. Advanced parental age is also associated with increased incidence of neurological and cardiovascular disease in offspring. Thus, elucidating the etiology of reproductive decline is of clinical importance. METHODS Deciphering the underlying processes that drive reproductive decline is particularly challenging in women in whom a discrete oocyte pool is established during embryogenesis and may remain dormant for tens of years. Instead, our understanding of the processes that drive reproductive senescence has emerged from studies in model organisms, both vertebrate and invertebrate, that are the focus of this literature review. CONCLUSIONS Studies of reproductive aging in model organisms not only have revealed the detrimental cellular changes that occur with age but also are helping identify major regulator proteins controlling them. Here, we discuss what we have learned from model organisms with respect to the molecular mechanisms that maintain both genome integrity and oocyte quality.
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Lin KY, Hsu HJ. Regulation of adult female germline stem cells by nutrient-responsive signaling. CURRENT OPINION IN INSECT SCIENCE 2020; 37:16-22. [PMID: 32070932 DOI: 10.1016/j.cois.2019.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 10/10/2019] [Accepted: 10/14/2019] [Indexed: 06/10/2023]
Abstract
Insect oogenesis is greatly affected by nutrient availability. When nutrients are abundant, oocytes are rapidly generated, but the process is slowed to conserve energy under nutrient-deficient conditions. To properly allocate limited resources toward oogenesis, systemic factors coordinate the behavioral response of ovarian germline stem cells (GSCs) to nutritional inputs by acting on the GSC itself, GSC supporting cells (the niche), or the adipose tissue surrounding the ovary. In this review, we describe current knowledge of the Drosophila ovarian GSC-niche-adipocyte system and major nutrient sensing pathways (insulin/IGF signaling, TOR signaling, and GCN2-dependent amino acid sensing) that intrinsically or extrinsically regulate GSC responses to nutrient signals.
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Affiliation(s)
- Kun-Yang Lin
- Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529, Taiwan; Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan; Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Hwei-Jan Hsu
- Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529, Taiwan; Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan; Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
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14
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Katsube H, Hinami Y, Yamazoe T, Inoue YH. Endoplasmic reticulum stress-induced cellular dysfunction and cell death in insulin-producing cells results in diabetes-like phenotypes in Drosophila. Biol Open 2019; 8:bio046524. [PMID: 31822470 PMCID: PMC6955230 DOI: 10.1242/bio.046524] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 12/02/2019] [Indexed: 12/28/2022] Open
Abstract
The destruction of pancreatic β cells leads to reduced insulin secretion and eventually causes diabetes. Various types of cellular stress are thought to be involved in destruction and/or malfunction of these cells. We show that endoplasmic reticulum (ER) stress accumulation in insulin-producing cells (IPCs) generated diabetes-like phenotypes in Drosophila To promote the accumulation of extra ER stress, we induced a dominant-negative form of a Drosophila ER chaperone protein (Hsc70-3DN) and demonstrate that it causes the unfolded-protein response (UPR) in various tissues. The numbers of IPCs decreased owing to apoptosis induction mediated by caspases. The apoptosis was driven by activation of Dronc, and subsequently by Drice and Dcp-1. Accordingly, the relative mRNA-expression levels of Drosophila insulin-like peptides significantly decreased. Consistent with these results, we demonstrate that glucose levels in larval haemolymph were significantly higher than those of controls. Accumulation of ER stress induced by continuous Hsc70-3DN expression in IPCs resulted in the production of undersized flies. Ectopic expression of Hsc70-3DN can induce more efficient ER stress responses and more severe phenotypes. We propose that ER stress is responsible for IPC loss and dysfunction, which results in diabetes-related pathogenesis in this Drosophila diabetes model. Moreover, inhibiting apoptosis partially prevents the ER stress-induced diabetes-like phenotypes.
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Affiliation(s)
- Hiroka Katsube
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Matsugasaki, Kyoto, Japan, 606-0962
| | - Yukiko Hinami
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Matsugasaki, Kyoto, Japan, 606-0962
| | - Tatsuki Yamazoe
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Matsugasaki, Kyoto, Japan, 606-0962
| | - Yoshihiro H Inoue
- Department of Insect Biomedical Research, Research Center for Insect Advanced Studies, Kyoto Institute of Technology, Matsugasaki, Kyoto, Japan, 606-0962
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15
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Drummond-Barbosa D. Local and Physiological Control of Germline Stem Cell Lineages in Drosophila melanogaster. Genetics 2019; 213:9-26. [PMID: 31488592 PMCID: PMC6727809 DOI: 10.1534/genetics.119.300234] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/09/2019] [Indexed: 12/12/2022] Open
Abstract
The long-term survival of any multicellular species depends on the success of its germline in producing high-quality gametes and maximizing survival of the offspring. Studies in Drosophila melanogaster have led our growing understanding of how germline stem cell (GSC) lineages maintain their function and adjust their behavior according to varying environmental and/or physiological conditions. This review compares and contrasts the local regulation of GSCs by their specialized microenvironments, or niches; discusses how diet and diet-dependent factors, mating, and microorganisms modulate GSCs and their developing progeny; and briefly describes the tie between physiology and development during the larval phase of the germline cycle. Finally, it concludes with broad comparisons with other organisms and some future directions for further investigation.
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Affiliation(s)
- Daniela Drummond-Barbosa
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
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16
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Dhiman N, Shweta K, Tendulkar S, Deshpande G, Ratnaparkhi GS, Ratnaparkhi A. Drosophila Mon1 constitutes a novel node in the brain-gonad axis that is essential for female germline maturation. Development 2019; 146:146/13/dev166504. [PMID: 31292144 DOI: 10.1242/dev.166504] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 05/23/2019] [Indexed: 01/16/2023]
Abstract
Monensin-sensitive 1 (Mon1) is an endocytic regulator that participates in the conversion of Rab5-positive early endosomes to Rab7-positive late endosomes. In Drosophila, loss of mon1 leads to sterility as the mon1 mutant females have extremely small ovaries with complete absence of late stage egg chambers - a phenotype reminiscent of mutations in the insulin pathway genes. Here, we show that expression of many Drosophila insulin-like peptides (ILPs) is reduced in mon1 mutants and feeding mon1 adults an insulin-rich diet can rescue the ovarian defects. Surprisingly, however, mon1 functions in the tyramine/octopaminergic neurons (OPNs) and not in the ovaries or the insulin-producing cells (IPCs). Consistently, knockdown of mon1 in only the OPNs is sufficient to mimic the ovarian phenotype, while expression of the gene in the OPNs alone can 'rescue' the mutant defect. Last, we have identified ilp3 and ilp5 as critical targets of mon1. This study thus identifies mon1 as a novel molecular player in the brain-gonad axis and underscores the significance of inter-organ systemic communication during development.
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Affiliation(s)
- Neena Dhiman
- Agarkar Research Institute (ARI), Pune, India.,Indian Institute of Science Education & Research (IISER), Pune, India
| | | | - Shweta Tendulkar
- Indian Institute of Science Education & Research (IISER), Pune, India
| | - Girish Deshpande
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
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17
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Rocco DA, Garcia ASG, Scudeler EL, Dos Santos DC, Nóbrega RH, Paluzzi JPV. Glycoprotein Hormone Receptor Knockdown Leads to Reduced Reproductive Success in Male Aedes aegypti. Front Physiol 2019; 10:266. [PMID: 30941056 PMCID: PMC6433794 DOI: 10.3389/fphys.2019.00266] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/28/2019] [Indexed: 12/18/2022] Open
Abstract
Glycoprotein hormone receptors mediate a diverse range of physiological functions in vertebrate and invertebrate organisms. The heterodimeric glycoprotein hormone GPA2/GPB5 and its receptor LGR1, constitute a recently discovered invertebrate neuroendocrine signaling system that remains to be functionally characterized. We previously reported that LGR1 is expressed in the testes of adult Aedes aegypti mosquitoes, where its immunoreactivity is particularly regionalized. Here, we show that LGR1 immunoreactivity is associated with the centriole adjunct of spermatids and is observed transiently during spermatogenesis in mosquitoes, where it may act to mediate the regulation of flagellar development. RNA interference to downregulate LGR1 expression was accomplished by feeding mosquito larvae with bacteria that produced LGR1-specific dsRNA, which led to defects in spermatozoa, characterized with shortened flagella. LGR1 knockdown mosquitoes also retained ∼60% less spermatozoa in reproductive organs and demonstrated reduced fertility compared to controls. To date, the endocrine regulation of spermatogenesis in mosquitoes remains an understudied research area. The distribution of LGR1 and detrimental effects of its knockdown on spermatogenesis in A. aegypti indicates that this heterodimeric glycoprotein hormone signaling system contributes significantly to the regulation of male reproductive biology in this important disease-vector.
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Affiliation(s)
- David A Rocco
- Department of Biology, York University, Toronto, ON, Canada
| | - Ana S G Garcia
- Department of Morphology, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Elton L Scudeler
- Department of Morphology, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Daniela C Dos Santos
- Department of Morphology, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil.,Electron Microscopy Center, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Rafael H Nóbrega
- Department of Morphology, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
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18
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Issigonis M, Newmark PA. From worm to germ: Germ cell development and regeneration in planarians. Curr Top Dev Biol 2019; 135:127-153. [DOI: 10.1016/bs.ctdb.2019.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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19
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Kubo A, Matsuka M, Minami R, Kimura F, Sakata-Niitsu R, Kokuryo A, Taniguchi K, Adachi-Yamada T, Nakagoshi H. Nutrient conditions sensed by the reproductive organ during development optimize male fecundity in Drosophila. Genes Cells 2018; 23:557-567. [DOI: 10.1111/gtc.12600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 04/30/2018] [Accepted: 05/06/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Ayuko Kubo
- Graduate School of Natural Science and Technology; Okayama University; Okayama Japan
| | - Mirai Matsuka
- Graduate School of Natural Science and Technology; Okayama University; Okayama Japan
| | - Ryunosuke Minami
- Graduate School of Natural Science and Technology; Okayama University; Okayama Japan
| | - Fumika Kimura
- Graduate School of Natural Science and Technology; Okayama University; Okayama Japan
| | - Rumi Sakata-Niitsu
- Department of Life Science; Faculty of Science; Gakushuin University; Tokyo Japan
| | - Akihiko Kokuryo
- Department of Life Science; Faculty of Science; Gakushuin University; Tokyo Japan
| | - Kiichiro Taniguchi
- Department of Life Science; Faculty of Science; Gakushuin University; Tokyo Japan
| | | | - Hideki Nakagoshi
- Graduate School of Natural Science and Technology; Okayama University; Okayama Japan
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20
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Kizhedathu A, Bagul AV, Guha A. Negative regulation of G2-M by ATR (mei-41)/Chk1(Grapes) facilitates tracheoblast growth and tracheal hypertrophy in Drosophila. eLife 2018; 7:29988. [PMID: 29658881 PMCID: PMC5953539 DOI: 10.7554/elife.29988] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 04/12/2018] [Indexed: 11/21/2022] Open
Abstract
Imaginal progenitors in Drosophila are known to arrest in G2 during larval stages and proliferate thereafter. Here we investigate the mechanism and implications of G2 arrest in progenitors of the adult thoracic tracheal epithelium (tracheoblasts). We report that tracheoblasts pause in G2 for ~48–56 h and grow in size over this period. Surprisingly, tracheoblasts arrested in G2 express drivers of G2-M like Cdc25/String (Stg). We find that mechanisms that prevent G2-M are also in place in this interval. Tracheoblasts activate Checkpoint Kinase 1/Grapes (Chk1/Grp) in an ATR/mei-41-dependent manner. Loss of ATR/Chk1 led to precocious mitotic entry ~24–32 h earlier. These divisions were apparently normal as there was no evidence of increased DNA damage or cell death. However, induction of precocious mitoses impaired growth of tracheoblasts and the tracheae they comprise. We propose that ATR/Chk1 negatively regulate G2-M in developing tracheoblasts and that G2 arrest facilitates cellular and hypertrophic organ growth. Every organism begins as a single cell. That cell, and all the other cells it generates over time, need to divide at the right time and in the right place to develop into an adult. As they do so, they pass through the stages of the cell cycle. As cells prepare to divide they enter into the first growth phase, G1, ramping up their metabolic activity. They then enter S phase, duplicate their DNA, and subsequently a second growth phase G2. Finally, during the mitotic phase, the chromosome separate and cells undergo cytokinesis to form new cells. Dividing cells can pause at certain stages of the cell cycle to assess whether the conditions are suitable to proceed. The length of the pause depends on the stage of development and the cell type. Signals around the cell provide the cues that it needs to make the decision. The fruit fly Drosophila melanogaster, for example, undergoes metamorphosis during development, meaning it transforms from a larva into an adult. The larva contains small patches of ‘progenitor’ cells that form the adult tissue. These remain paused for various intervals during larval life and restart their cell cycle as the animal develops. A key challenge in biology is to understand how these progenitors pause and what makes them start dividing again. Here, Kizhedathu, Bagul and Guha uncover a new mechanism that pauses the cell cycle in developing animal cells. Progenitors of the respiratory system in the adult fruit fly pause at the G2 stage of the cell cycle during larval life. Some of these progenitors, from a part of the larva called the dorsal trunk, go on to form the structures of the adult respiratory system. By counting the cells and tracking their dynamics with fluorescent labels, Kizhedathu et al. revealed that the progenitor cells pause for between 48 and to 56 hours. Previous research suggested that this pause happens because the cells lack a protein essential for mitosis called Cdc25/String. However, these progenitors were producing Cdc25/String. They stopped dividing because they also made another protein, known as Checkpoint Kinase 1/Grapes (Chk1/Grp). Chk1 is known to add a chemical modification to Cdc25, which dampens its activity and stops the cell cycle from progressing. This is likely what allow the flies to co-ordinate their development and give the cells more time to grow. When Chk1 was experimentally removed, it reactivated the paused cells sooner, resulting in smaller cells and a smaller respiratory organ. This work extends our understanding of stem cell dynamics and growth during development. Previous work has shown that cells that give rise to muscles and the neural tube (the precursor of the central nervous system) also pause their cell cycle in G2. Understanding more about how this happens could open new avenues for research into developmental disease.
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Affiliation(s)
- Amrutha Kizhedathu
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,SASTRA University, Thanjavur, India
| | - Archit V Bagul
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
| | - Arjun Guha
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
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21
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Drosophila Models to Investigate Insulin Action and Mechanisms Underlying Human Diabetes Mellitus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1076:235-256. [DOI: 10.1007/978-981-13-0529-0_13] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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22
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Tanabe K, Okazaki R, Kaizuka K, Inoue YH. Time-lapse Observation of Chromosomes, Cytoskeletons and Cell Organelles during Male Meiotic Divisions in Drosophila. Bio Protoc 2017; 7:e2225. [PMID: 34541226 DOI: 10.21769/bioprotoc.2225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/12/2017] [Accepted: 03/16/2017] [Indexed: 11/02/2022] Open
Abstract
In this protocol, we provide an experimental procedure that perform time-lapse observation of intra-cellular structures such as chromosomes, cytoskeletons and cell organelles during meiotic cell divisions in Drosophila males. As primary spermatocyte is the largest dividing diploid cell in Drosophila, which is equivalent in size to mammalian cultured cells, one can observe dynamics of cellular components during division of the model cells more precisely. Using this protocol, we have showed that a microtubule-associated protein plays an essential role in microtubule dynamics and initiation of cleavage furrowing through interaction between microtubules and actomyosin filaments. We have also reported that nuclear membrane components are required for a formation and/or maintenance of the spindle envelope essential for cytokinesis in the Drosophila cells.
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Affiliation(s)
- Karin Tanabe
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan
| | - Ryotaro Okazaki
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan
| | - Kana Kaizuka
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan
| | - Yoshihiro H Inoue
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan
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23
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Zhuo JC, Xue J, Lu JB, Huang HJ, Xu HJ, Zhang CX. Effect of RNAi-mediated knockdown of NlTOR gene on fertility of male Nilaparvata lugens. JOURNAL OF INSECT PHYSIOLOGY 2017; 98:149-159. [PMID: 28069465 DOI: 10.1016/j.jinsphys.2017.01.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 01/05/2017] [Accepted: 01/05/2017] [Indexed: 06/06/2023]
Abstract
The target gene of rapamycin (TOR) is conserved from invertebrates to vertebrates, and plays critical roles in cell growth, nutrient sensing, lifespan and reproduction. In this paper, we employed RNA interference (RNAi) to study the function of TOR in male brown planthoppers (BPH), Nilaparvata lugens. Here we discovered that no offspring was produced when wildtype females BPH mated with NlTOR RNAi males. To understand the influence of NlTOR on male BPH infertility, we dissected the reproductive system of a NlTOR RNAi male, and found that the testes were normal and the seminal vesicles were full of sperm, while the accessory gland was poorly developed after knocking down NlTOR expression. Furthermore, transmission electron microscopy data showed defective structure of epithelial cells of the accessory gland, and the deferent duct was collapsed. Also, behavioral data revealed that wildtype virgin females refused to mate with NlTOR RNAi males, and the acoustic signals of dsNlTOR males differed from controls. Our results indicate that NlTOR plays an essential role in the development of the male BPH reproductive system and regulates mating behavior.
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Affiliation(s)
- Ji-Chong Zhuo
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Jian Xue
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Jia-Bao Lu
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Hai-Jian Huang
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Hai-Jun Xu
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China.
| | - Chuan-Xi Zhang
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China.
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24
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Abstract
In this review, Ng and Shyh-Chang review recent metabolomic studies of stem cell metabolism that have revealed how metabolic pathways can convey changes in the extrinsic environment or their niche to program stem cell fates. Advances in metabolomics have deepened our understanding of the roles that specific modes of metabolism play in programming stem cell fates. Here, we review recent metabolomic studies of stem cell metabolism that have revealed how metabolic pathways can convey changes in the extrinsic environment or their niche to program stem cell fates. The metabolic programming of stem cells represents a fine balance between the intrinsic needs of a cellular state and the constraints imposed by extrinsic conditions. A more complete understanding of these needs and constraints will afford us greater mastery over our control of stem cell fates.
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Affiliation(s)
| | - Huck-Hui Ng
- Genome Institute of Singapore, Singapore 138675
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25
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Amoyel M, Hillion KH, Margolis SR, Bach EA. Somatic stem cell differentiation is regulated by PI3K/Tor signaling in response to local cues. Development 2016; 143:3914-3925. [PMID: 27633989 DOI: 10.1242/dev.139782] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/06/2016] [Indexed: 12/25/2022]
Abstract
Stem cells reside in niches that provide signals to maintain self-renewal, and differentiation is viewed as a passive process that depends on loss of access to these signals. Here, we demonstrate that the differentiation of somatic cyst stem cells (CySCs) in the Drosophila testis is actively promoted by PI3K/Tor signaling, as CySCs lacking PI3K/Tor activity cannot differentiate properly. We find that an insulin peptide produced by somatic cells immediately outside of the stem cell niche acts locally to promote somatic differentiation through Insulin-like receptor (InR) activation. These results indicate that there is a local 'differentiation' niche that upregulates PI3K/Tor signaling in the early daughters of CySCs. Finally, we demonstrate that CySCs secrete the Dilp-binding protein ImpL2, the Drosophila homolog of IGFBP7, into the stem cell niche, which blocks InR activation in CySCs. Thus, we show that somatic cell differentiation is controlled by PI3K/Tor signaling downstream of InR and that the local production of positive and negative InR signals regulates the differentiation niche. These results support a model in which leaving the stem cell niche and initiating differentiation are actively induced by signaling.
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Affiliation(s)
- Marc Amoyel
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA .,Helen L. and Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA
| | - Kenzo-Hugo Hillion
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA
| | - Shally R Margolis
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA
| | - Erika A Bach
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA .,Helen L. and Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, 550 1st Avenue, New York, NY 10016, USA
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26
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Brill JA, Yildirim S, Fabian L. Phosphoinositide signaling in sperm development. Semin Cell Dev Biol 2016; 59:2-9. [PMID: 27321976 DOI: 10.1016/j.semcdb.2016.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 06/15/2016] [Indexed: 01/15/2023]
Abstract
Phosphatidylinositol phosphates (PIPs)1 are membrane lipids with crucial roles during cell morphogenesis, including the establishment of cytoskeletal organization, membrane trafficking, cell polarity, cell-cycle control and signaling. Recent studies in mice (Mus musculus), fruit flies (Drosophila melanogaster) and other organisms have defined germ cell intrinsic requirements for these lipids and their regulatory enzymes in multiple aspects of sperm development. In particular, PIP levels are crucial in germline stem cell maintenance, spermatogonial proliferation and survival, spermatocyte cytokinesis, spermatid polarization, sperm tail formation, nuclear shaping, and production of mature, motile sperm. Here, we briefly review the stages of spermatogenesis and discuss the roles of PIPs and their regulatory enzymes in male germ cell development.
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Affiliation(s)
- Julie A Brill
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G OA4, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Institute of Medical Science, University of Toronto, Toronto, ON M5S 1A8, Canada.
| | - Sukriye Yildirim
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G OA4, Canada.
| | - Lacramioara Fabian
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G OA4, Canada.
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27
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Barandoc-Alviar K, Ramirez GM, Rotenberg D, Whitfield AE. Analysis of Acquisition and Titer of Maize Mosaic Rhabdovirus in Its Vector, Peregrinus maidis (Hemiptera: Delphacidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2016; 16:iev154. [PMID: 28076276 PMCID: PMC5779079 DOI: 10.1093/jisesa/iev154] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/09/2015] [Indexed: 06/06/2023]
Abstract
The corn planthopper, Peregrinus maidis (Ashmead) (Hemiptera: Delphacidae), transmits Maize mosaic rhabdovirus (MMV), an important pathogen of maize and sorghum, in a persistent propagative manner. To better understand the vectorial capacity of P. maidis, we determined the efficiency of MMV acquisition by nymphal and adult stages, and characterized MMV titer through development. Acquisition efficiency, i.e., proportion of insects that acquired the virus, was determined by reverse transcriptase polymerase chain reaction (RT-PCR) and virus titer of individual insects was estimated by quantitative RT-PCR. Acquisition efficiency of MMV differed significantly between nymphs and adults. MMV titer increased significantly over time and throughout insect development from nymphal to adult stage, indication of virus replication in the vector during development. There was a positive association between the vector developmental stage and virus titer. Also, the average titer in male insects was threefold higher than female titers, and this difference persisted up to 30 d post adult eclosion. Overall, our findings indicate that nymphs are more efficient than adults at acquiring MMV and virus accumulated in the vector over the course of nymphal development. Furthermore, sustained infection over the lifespan of P. maidis indicates a potentially high capacity of this vector to transmit MMV.
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Affiliation(s)
| | - Girly M Ramirez
- Department of Statistics, Kansas State University, Manhattan, KS 66506, USA, and
| | - Dorith Rotenberg
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
| | - Anna E Whitfield
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA,
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28
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Min-Wen JC, Jun-Hao ET, Shyh-Chang N. Stem cell mitochondria during aging. Semin Cell Dev Biol 2016; 52:110-8. [PMID: 26851627 DOI: 10.1016/j.semcdb.2016.02.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 01/28/2016] [Accepted: 02/01/2016] [Indexed: 01/06/2023]
Abstract
Mitochondria are the central hubs of cellular metabolism, equipped with their own mitochondrial DNA (mtDNA) blueprints to direct part of the programming of mitochondrial oxidative metabolism and thus reactive oxygen species (ROS) levels. In stem cells, many stem cell factors governing the intricate balance between self-renewal and differentiation have been found to directly regulate mitochondrial processes to control stem cell behaviors during tissue regeneration and aging. Moreover, numerous nutrient-sensitive signaling pathways controlling organismal longevity in an evolutionarily conserved fashion also influence stem cell-mediated tissue homeostasis during aging via regulation of stem cell mitochondria. At the genomic level, it has been demonstrated that heritable mtDNA mutations and variants affect mammalian stem cell homeostasis and influence the risk for human degenerative diseases during aging. Because such a multitude of stem cell factors and signaling pathways ultimately converge on the mitochondria as the primary mechanism to modulate cellular and organismal longevity, it would be most efficacious to develop technologies to therapeutically target and direct mitochondrial repair in stem cells, as a unified strategy to combat aging-related degenerative diseases in the future.
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Affiliation(s)
- Jason Chua Min-Wen
- Stem Cell & Regenerative Biology, Genome Institute of Singapore, 60 Biopolis St, S138672, Singapore
| | - Elwin Tan Jun-Hao
- Stem Cell & Regenerative Biology, Genome Institute of Singapore, 60 Biopolis St, S138672, Singapore
| | - Ng Shyh-Chang
- Stem Cell & Regenerative Biology, Genome Institute of Singapore, 60 Biopolis St, S138672, Singapore.
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29
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Dorn DC, Dorn A. Stem cell autotomy and niche interaction in different systems. World J Stem Cells 2015; 7:922-944. [PMID: 26240680 PMCID: PMC4515436 DOI: 10.4252/wjsc.v7.i6.922] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 05/27/2015] [Indexed: 02/06/2023] Open
Abstract
The best known cases of cell autotomy are the formation of erythrocytes and thrombocytes (platelets) from progenitor cells that reside in special niches. Recently, autotomy of stem cells and its enigmatic interaction with the niche has been reported from male germline stem cells (GSCs) in several insect species. First described in lepidopterans, the silkmoth, followed by the gipsy moth and consecutively in hemipterans, foremost the milkweed bug. In both, moths and the milkweed bug, GSCs form finger-like projections toward the niche, the apical cells (homologs of the hub cells in Drosophila). Whereas in the milkweed bug the projection terminals remain at the surface of the niche cells, in the gipsy moth they protrude deeply into the singular niche cell. In both cases, the projections undergo serial retrograde fragmentation with progressing signs of autophagy. In the gipsy moth, the autotomized vesicles are phagocytized and digested by the niche cell. In the milkweed bug the autotomized vesicles accumulate at the niche surface and disintegrate. Autotomy and sprouting of new projections appears to occur continuously. The significance of the GSC-niche interactions, however, remains enigmatic. Our concept on the signaling relationship between stem cell-niche in general and GSC and niche (hub cells and cyst stem cells) in particular has been greatly shaped by Drosophila melanogaster. In comparing the interactions of GSCs with their niche in Drosophila with those in species exhibiting GSC autotomy it is obvious that additional or alternative modes of stem cell-niche communication exist. Thus, essential signaling pathways, including niche-stem cell adhesion (E-cadherin) and the direction of asymmetrical GSC division - as they were found in Drosophila - can hardly be translated into the systems where GSC autotomy was reported. It is shown here that the serial autotomy of GSC projections shows remarkable similarities with Wallerian axonal destruction, developmental axon pruning and dying-back degeneration in neurodegenerative diseases. Especially the hypothesis of an existing evolutionary conserved “autodestruction program” in axons that might also be active in GSC projections appears attractive. Investigations on the underlying signaling pathways have to be carried out. There are two other well known cases of programmed cell autotomy: the enucleation of erythroblasts in the process of erythrocyte maturation and the segregation of thousands of thrombocytes (platelets) from one megakaryocyte. Both progenitor cell types - erythroblasts and megakaryocytes - are associated with a niche in the bone marrow, erythroblasts with a macrophage, which they surround, and the megakaryocytes with the endothelial cells of sinusoids and their extracellular matrix. Although the regulatory mechanisms may be specific in each case, there is one aspect that connects all described processes of programmed cell autotomy and neuronal autodestruction: apoptotic pathways play always a prominent role. Studies on the role of male GSC autotomy in stem cell-niche interaction have just started but are expected to reveal hitherto unknown ways of signal exchange. Spermatogenesis in mammals advance our understanding of insect spermatogenesis. Mammal and insect spermatogenesis share some broad principles, but a comparison of the signaling pathways is difficult. We have intimate knowledge from Drosophila, but of almost no other insect, and we have only limited knowledge from mammals. The discovery of stem cell autotomy as part of the interaction with the niche promises new general insights into the complicated stem cell-niche interdependence.
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Koyuncu S, Irmak D, Saez I, Vilchez D. Defining the General Principles of Stem Cell Aging: Lessons from Organismal Models. CURRENT STEM CELL REPORTS 2015. [DOI: 10.1007/s40778-015-0017-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Aldrich JC, Maggert KA. Transgenerational inheritance of diet-induced genome rearrangements in Drosophila. PLoS Genet 2015; 11:e1005148. [PMID: 25885886 PMCID: PMC4401788 DOI: 10.1371/journal.pgen.1005148] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 03/17/2015] [Indexed: 12/17/2022] Open
Abstract
Ribosomal RNA gene (rDNA) copy number variation modulates heterochromatin formation and influences the expression of a large fraction of the Drosophila genome. This discovery, along with the link between rDNA, aging, and disease, high-lights the importance of understanding how natural rDNA copy number variation arises. Pursuing the relationship between rDNA expression and stability, we have discovered that increased dietary yeast concentration, emulating periods of dietary excess during life, results in somatic rDNA instability and copy number reduction. Modulation of Insulin/TOR signaling produces similar results, indicating a role for known nutrient sensing signaling pathways in this process. Furthermore, adults fed elevated dietary yeast concentrations produce offspring with fewer rDNA copies demonstrating that these effects also occur in the germline, and are transgenerationally heritable. This finding explains one source of natural rDNA copy number variation revealing a clear long-term consequence of diet.
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Affiliation(s)
- John C. Aldrich
- Department of Biology, College of Science, Texas A&M University, College Station, Texas, United States of America
| | - Keith A. Maggert
- Department of Biology, College of Science, Texas A&M University, College Station, Texas, United States of America
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, Arizona, United States of America
- * E-mail:
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Wei D, Li HM, Yang WJ, Wei DD, Dou W, Huang Y, Wang JJ. Transcriptome profiling of the testis reveals genes involved in spermatogenesis and marker discovery in the oriental fruit fly, Bactrocera dorsalis. INSECT MOLECULAR BIOLOGY 2015; 24:41-57. [PMID: 25255964 DOI: 10.1111/imb.12134] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The testis is a highly specialized tissue that plays a vital role in ensuring fertility by producing spermatozoa, which are transferred to the female during mating. Spermatogenesis is a complex process, resulting in the production of mature sperm, and involves significant structural and biochemical changes in the seminiferous epithelium of the adult testis. The identification of genes involved in spermatogenesis of Bactrocera dorsalis (Hendel) is critical for a better understanding of its reproductive development. In this study, we constructed a cDNA library of testes from male B. dorsalis adults at different ages, and performed de novo transcriptome sequencing to produce a comprehensive transcript data set, using Illumina sequencing technology. The analysis yielded 52 016 732 clean reads, including a total of 4.65 Gb of nucleotides. These reads were assembled into 47 677 contigs (average 443 bp) and then clustered into 30 516 unigenes (average 756 bp). Based on BLAST hits with known proteins in different databases, 20 921 unigenes were annotated with a cut-off E-value of 10(-5). The transcriptome sequences were further annotated using the Clusters of Orthologous Groups, Gene Orthology and the Kyoto Encyclopedia of Genes and Genomes databases. Functional genes involved in spermatogenesis were analysed, including cell cycle proteins, metalloproteins, actin, and ubiquitin and antihyperthermia proteins. Several testis-specific genes were also identified. The transcripts database will help us to understand the molecular mechanisms underlying spermatogenesis in B. dorsalis. Furthermore, 2913 simple sequence repeats and 151 431 single nucleotide polymorphisms were identified, which will be useful for investigating the genetic diversity of B. dorsalis in the future.
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Affiliation(s)
- D Wei
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China
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Fairchild MJ, Smendziuk CM, Tanentzapf G. A somatic permeability barrier around the germline is essential for Drosophila spermatogenesis. Development 2014; 142:268-81. [PMID: 25503408 DOI: 10.1242/dev.114967] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Interactions between the soma and germline are essential for gametogenesis. In the Drosophila testis, differentiating germ cells are encapsulated by two somatic cells that surround the germline throughout spermatogenesis. chickadee (chic), the fly ortholog of Profilin, mediates soma-germline interactions. Knockdown of Chic in the soma results in sterility and severely disrupted spermatogenesis due to defective encapsulation. To study this defect further, we developed a permeability assay to analyze whether the germline is isolated from the surrounding environment by the soma. We find that germline encapsulation by the soma is, by itself, insufficient for the formation of a permeability barrier, but that such a barrier gradually develops during early spermatogenesis. Thus, germline stem cells, gonialblasts and early spermatogonia are not isolated from the outside environment. By late spermatocyte stages, however, a permeability barrier is formed by the soma. Furthermore, we find that, concomitant with formation of the permeability barrier, septate junction markers are expressed in the soma and localize to junctional sites connecting the two somatic cells that surround the germline. Importantly, knockdown of septate junction components also disrupts the permeability barrier. Finally, we show that germline differentiation is delayed when the permeability barrier is compromised. We propose that the permeability barrier around the germline serves an important regulatory function during spermatogenesis by shaping the signaling events that take place between the soma and the germline.
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Affiliation(s)
- Michael J Fairchild
- Department of Cellular and Physiological Sciences, 2350 Health Sciences Mall, University of British Columbia, Vancouver V6T 1Z3, Canada
| | - Christopher M Smendziuk
- Department of Cellular and Physiological Sciences, 2350 Health Sciences Mall, University of British Columbia, Vancouver V6T 1Z3, Canada
| | - Guy Tanentzapf
- Department of Cellular and Physiological Sciences, 2350 Health Sciences Mall, University of British Columbia, Vancouver V6T 1Z3, Canada
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Ricketts PGA, Minimair M, Yates RW, Klaus AV. The effects of glutathione, insulin and oxidative stress on cultured spermatogenic cysts. SPERMATOGENESIS 2014; 1:159-171. [PMID: 22319665 DOI: 10.4161/spmg.1.2.17031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Revised: 06/23/2011] [Accepted: 06/24/2011] [Indexed: 01/13/2023]
Abstract
Spermatogenesis is a series of cellular processes that leads to the development of motile, elongate sperm cells. Mitotic expansion of spermatogenic stem cells is followed by two meiotic cell divisions that yield haploid round spermatids which then transform from a spherical form into an elongate, highly polarized form. In Drosophila, spermatogenesis takes place within encapsulating cysts that contain spermatogenic cells. Spermatogenic cysts were isolated and grown in culture over the course of 96 hours. Cultures were treated with buthionine sulfoximine (BSO), glutathione (GSH), insulin and GSH+insulin in order to test the effects of these agents on cyst viability. The addition of glutathione and exogenous insulin to cultured spermatogenic cysts each appeared to have a positive effect on early spermatogenic cyst survival in vitro at some timepoints. The addition of GSH+insulin together had no significant effect on early spermatogenic cyst survival in vitro. Oxidative stress induced by BSO resulted in a significant decrease and/or complete loss of specific early spermatogenic cyst types and the abnormal development of elongating cysts in culture. This culture system offers the opportunity for high-resolution analysis of spermatogenic processes not previously possible.
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Affiliation(s)
- Peta-Gay A Ricketts
- Department of Biological Sciences; Seton Hall University; South Orange, NJ USA
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Steroid signaling promotes stem cell maintenance in the Drosophila testis. Dev Biol 2014; 394:129-41. [PMID: 25093968 DOI: 10.1016/j.ydbio.2014.07.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 12/22/2022]
Abstract
Stem cell regulation by local signals is intensely studied, but less is known about the effects of hormonal signals on stem cells. In Drosophila, the primary steroid twenty-hydroxyecdysone (20E) regulates ovarian germline stem cells (GSCs) but was considered dispensable for testis GSC maintenance. Male GSCs reside in a microenvironment (niche) generated by somatic hub cells and adjacent cyst stem cells (CySCs). Here, we show that depletion of 20E from adult males by overexpressing a dominant negative form of the Ecdysone receptor (EcR) or its heterodimeric partner ultraspiracle (usp) causes GSC and CySC loss that is rescued by 20E feeding, uncovering a requirement for 20E in stem cell maintenance. EcR and USP are expressed, activated and autonomously required in the CySC lineage to promote CySC maintenance, as are downstream genes ftz-f1 and E75. In contrast, GSCs non-autonomously require ecdysone signaling. Global inactivation of EcR increases cell death in the testis that is rescued by expression of EcR-B2 in the CySC lineage, indicating that ecdysone signaling supports stem cell viability primarily through a specific receptor isoform. Finally, EcR genetically interacts with the NURF chromatin-remodeling complex, which we previously showed maintains CySCs. Thus, although 20E levels are lower in males than females, ecdysone signaling acts through distinct cell types and effectors to ensure both ovarian and testis stem cell maintenance.
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de Sousa JT, Milan M, Bargelloni L, Pauletto M, Matias D, Joaquim S, Matias AM, Quillien V, Leitão A, Huvet A. A microarray-based analysis of gametogenesis in two Portuguese populations of the European clam Ruditapes decussatus. PLoS One 2014; 9:e92202. [PMID: 24643002 PMCID: PMC3958495 DOI: 10.1371/journal.pone.0092202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 02/19/2014] [Indexed: 02/01/2023] Open
Abstract
The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed in four gonadal maturation stages from two different Portuguese wild populations, characterized by different responses to spawning induction when used as progenitors in hatchery. A comparison between the two populations elucidated a specific pathway involved in the recognition signals and binding between the oocyte and components of the sperm plasma membrane. We suggest that this pathway can explain part of the differences in terms of spawning induction success between the two populations. In addition, sexes and reproductive stages were compared and a correlation between mRNA levels and gonadal area was investigated. The lists of differentially expressed genes revealed that sex explains most of the variance in gonadal gene expression. Additionally, genes like Foxl2, vitellogenin, condensing 2, mitotic apparatus protein p62, Cep57, sperm associated antigens 6, 16 and 17, motile sperm domain containing protein 2, sperm surface protein Sp17, sperm flagellar proteins 1 and 2 and dpy-30, were identified as being correlated with the gonad area and therefore supposedly with the number and/or the size of the gametes produced.
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Affiliation(s)
- Joana Teixeira de Sousa
- IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France
- IPMA, Olhão, Portugal
| | - Massimo Milan
- Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy
| | - Luca Bargelloni
- Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy
| | - Marianna Pauletto
- Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro, Italy
| | | | | | | | - Virgile Quillien
- IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France
| | | | - Arnaud Huvet
- IFREMER, UMR CNRS 6539, Laboratoire des Sciences de l'Environnement Marin, Plouzané, France
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37
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Shim J, Gururaja-Rao S, Banerjee U. Nutritional regulation of stem and progenitor cells in Drosophila. Development 2014; 140:4647-56. [PMID: 24255094 DOI: 10.1242/dev.079087] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Stem cells and their progenitors are maintained within a microenvironment, termed the niche, through local cell-cell communication. Systemic signals originating outside the niche also affect stem cell and progenitor behavior. This review summarizes studies that pertain to nutritional effects on stem and progenitor cell maintenance and proliferation in Drosophila. Multiple tissue types are discussed that utilize the insulin-related signaling pathway to convey nutritional information either directly to these progenitors or via other cell types within the niche. The concept of systemic control of these cell types is not limited to Drosophila and may be functional in vertebrate systems, including mammals.
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Affiliation(s)
- Jiwon Shim
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
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38
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Badisco L, Van Wielendaele P, Vanden Broeck J. Eat to reproduce: a key role for the insulin signaling pathway in adult insects. Front Physiol 2013; 4:202. [PMID: 23966944 PMCID: PMC3735985 DOI: 10.3389/fphys.2013.00202] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/17/2013] [Indexed: 01/25/2023] Open
Abstract
Insects, like all heterotrophic organisms, acquire from their food the nutrients that are essential for anabolic processes that lead to growth (larval stages) or reproduction (adult stage). In adult females, this nutritional input is processed and results in a very specific output, i.e., the production of fully developed eggs ready for fertilization and deposition. An important role in this input-output transition is attributed to the insulin signaling pathway (ISP). The ISP is considered to act as a sensor of the organism's nutritional status and to stimulate the progression of anabolic events when the status is positive. In several insect species belonging to different orders, the ISP has been demonstrated to positively control vitellogenesis and oocyte growth. Whether or not ISP acts herein via a mediator action of lipophilic insect hormones (ecdysteroids and juvenile hormone) remains debatable and might be differently controlled in different insect orders. Most likely, insulin-related peptides, ecdysteroids and juvenile hormone are involved in a complex regulatory network, in which they mutually influence each other and in which the insect's nutritional status is a crucial determinant of the network's output. The current review will present an overview of the regulatory role of the ISP in female insect reproduction and its interaction with other pathways involving nutrients, lipophilic hormones and neuropeptides.
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Affiliation(s)
- Liesbeth Badisco
- Department of Animal Physiology and Neurobiology, Research Group of Molecular Developmental Physiology and Signal Transduction KU Leuven, Leuven, Belgium
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Shyh-Chang N, Daley GQ, Cantley LC. Stem cell metabolism in tissue development and aging. Development 2013; 140:2535-47. [PMID: 23715547 DOI: 10.1242/dev.091777] [Citation(s) in RCA: 410] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recent advances in metabolomics and computational analysis have deepened our appreciation for the role of specific metabolic pathways in dictating cell fate. Once thought to be a mere consequence of the state of a cell, metabolism is now known to play a pivotal role in dictating whether a cell proliferates, differentiates or remains quiescent. Here, we review recent studies of metabolism in stem cells that have revealed a shift in the balance between glycolysis, mitochondrial oxidative phosphorylation and oxidative stress during the maturation of adult stem cells, and during the reprogramming of somatic cells to pluripotency. These insights promise to inform strategies for the directed differentiation of stem cells and to offer the potential for novel metabolic or pharmacological therapies to enhance regeneration and the treatment of degenerative disease.
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Affiliation(s)
- Ng Shyh-Chang
- Stem Cell Transplantation Program, Division of Pediatric Hematology/Oncology, Boston Children's Hospital and Dana Farber Cancer Institute, Boston, MA 02115, USA
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40
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Abstract
Tyrosine phosphorylation plays a significant role in a wide range of cellular processes. The Drosophila genome encodes more than 20 receptor tyrosine kinases and extensive studies in the past 20 years have illustrated their diverse roles and complex signaling mechanisms. Although some receptor tyrosine kinases have highly specific functions, others strikingly are used in rather ubiquitous manners. Receptor tyrosine kinases regulate a broad expanse of processes, ranging from cell survival and proliferation to differentiation and patterning. Remarkably, different receptor tyrosine kinases share many of the same effectors and their hierarchical organization is retained in disparate biological contexts. In this comprehensive review, we summarize what is known regarding each receptor tyrosine kinase during Drosophila development. Astonishingly, very little is known for approximately half of all Drosophila receptor tyrosine kinases.
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Affiliation(s)
- Richelle Sopko
- Department of Genetics, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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41
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Stine RR, Matunis EL. Stem cell competition: finding balance in the niche. Trends Cell Biol 2013; 23:357-64. [PMID: 23597843 DOI: 10.1016/j.tcb.2013.03.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 02/28/2013] [Accepted: 03/01/2013] [Indexed: 01/11/2023]
Abstract
Adult stem cells reside in local microenvironments (niches) that produce signals regulating the outcome of stem cell divisions and stem cell-niche interactions. Limited space and signals in the niche often force stem cells to compete with one another. Although previous studies have uncovered several examples of genetically distinct stem cells competing for niche access, recent studies demonstrate that genetically equivalent stem cells compete under normal conditions, resulting in dynamic stem cell behavior in the niche. New work in multiple vertebrate and invertebrate tissues shows that stem cell competition occurs continuously and mutations disrupting the balance between competing stem cells can cause diseases and defects in the niche. This review discusses recent insights into stem cell competition in mammals and Drosophila.
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Affiliation(s)
- Rachel R Stine
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Matunis EL, Stine RR, de Cuevas M. Recent advances in Drosophila male germline stem cell biology. SPERMATOGENESIS 2012; 2:137-144. [PMID: 23087833 PMCID: PMC3469437 DOI: 10.4161/spmg.21763] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The ability of stem cells to divide asymmetrically to produce both self-renewing and differentiating daughter cells sustains many adult tissues, but germline stem cells (GSCs) are unique among stem cells as they perpetuate the genome of the species. The cellular and molecular mechanisms regulating most mammalian stem cells in their endogenous local microenvironments, or niches, are quite challenging to study. However, studies of stem cell niches such as those found in the Drosophila gonads have proven very useful. In these tissues, GSCs are housed in a readily identifiable niche, and the ability to genetically manipulate these cells and their neighbors has uncovered several fundamental mechanisms that are relevant to stem cells more generally. Here, we summarize recent work on the regulation of GSCs in the Drosophila testis niche by intercellular signals, and on the intracellular mechanisms that cooperate with these signals to ensure the survival of the germline. This review focuses on GSCs within the adult Drosophila testis; somatic stem cells in this tissue are reviewed by Zoller and Schulz in this issue.(1) For a review of the testis niche as a whole, see de Cuevas and Matunis,(2) and for more comprehensive reviews of the Drosophila testis, refer to Fuller(3) and Davies and Fuller.(4).
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Affiliation(s)
- Erika L. Matunis
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
| | - Rachel R. Stine
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
| | - Margaret de Cuevas
- Department of Cell Biology; Johns Hopkins University School of Medicine; Baltimore, MD USA
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Jouaux A, Franco A, Heude-Berthelin C, Sourdaine P, Blin JL, Mathieu M, Kellner K. Identification of Ras, Pten and p70S6K homologs in the Pacific oyster Crassostrea gigas and diet control of insulin pathway. Gen Comp Endocrinol 2012; 176:28-38. [PMID: 22202600 DOI: 10.1016/j.ygcen.2011.12.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 12/05/2011] [Accepted: 12/11/2011] [Indexed: 11/23/2022]
Abstract
Insulin pathways were demonstrated from invertebrates to vertebrates to be involved in the regulation of numerous processes including storage metabolism and reproduction. In addition, insulin system may integrate variations of environmental conditions like dietary restrictions. In the Pacific oyster Crassostrea gigas, reproductive and storage compartments are closely intricated in the gonadal area and their respective development was found to be dependant of trophic conditions. For these reasons, C. gigas is an original and interesting model for investigating the role of insulin control in the balance between storage and reproduction and the integration of environmental parameters. On the basis of sequence conservation, we identified three potential elements of the oyster insulin pathway, Ras, Pten and p70S6K and we investigated their expression levels in various tissues. In the gonadal area, we used laser microdissection in order to precise the targeted contribution of insulin signaling to the restoration of storage tissue and to the control of vitellogenesis. Food deprivation during gametogenesis reinitiation stage led to reduced proliferations of gonia and also to modulate insulin signal by transcriptional activation of insulin pathway elements.
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Affiliation(s)
- A Jouaux
- CNRS-INEE FRE3484 BioMEA Biologie des Mollusques marins et Ecosystèmes associés IFR146 ICORE, Université de Caen Basse-Normandie, F 14032 Caen Cedex, France.
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44
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Roth TM, Chiang CYA, Inaba M, Yuan H, Salzmann V, Roth CE, Yamashita YM. Centrosome misorientation mediates slowing of the cell cycle under limited nutrient conditions in Drosophila male germline stem cells. Mol Biol Cell 2012; 23:1524-32. [PMID: 22357619 PMCID: PMC3327310 DOI: 10.1091/mbc.e11-12-0999] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A novel mechanism is found by which Drosophila male germline stem cells (GSCs) slow their cell cycle under limited nutrient conditions. Upon culturing in poor media, GSCs misorient their centrosomes with respect to the stem cell niche, activating the centrosome orientation checkpoint and leading to slowdown of the cell cycle. Drosophila male germline stem cells (GSCs) divide asymmetrically, balancing self-renewal and differentiation. Although asymmetric stem cell division balances between self-renewal and differentiation, it does not dictate how frequently differentiating cells must be produced. In male GSCs, asymmetric GSC division is achieved by stereotyped positioning of the centrosome with respect to the stem cell niche. Recently we showed that the centrosome orientation checkpoint monitors the correct centrosome orientation to ensure an asymmetric outcome of the GSC division. When GSC centrosomes are not correctly oriented with respect to the niche, GSC cell cycle is arrested/delayed until the correct centrosome orientation is reacquired. Here we show that induction of centrosome misorientation upon culture in poor nutrient conditions mediates slowing of GSC cell proliferation via activation of the centrosome orientation checkpoint. Consistently, inactivation of the centrosome orientation checkpoint leads to lack of cell cycle slowdown even under poor nutrient conditions. We propose that centrosome misorientation serves as a mediator that transduces nutrient information into stem cell proliferation, providing a previously unappreciated mechanism of stem cell regulation in response to nutrient conditions.
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Affiliation(s)
- Therese M Roth
- Life Sciences Institute, Center for Stem Cell Biology, University of Michigan, Ann Arbor, MI 48109, USA
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45
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Losick VP, Morris LX, Fox DT, Spradling A. Drosophila stem cell niches: a decade of discovery suggests a unified view of stem cell regulation. Dev Cell 2011; 21:159-71. [PMID: 21763616 PMCID: PMC6894370 DOI: 10.1016/j.devcel.2011.06.018] [Citation(s) in RCA: 236] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2011] [Revised: 06/03/2011] [Accepted: 06/10/2011] [Indexed: 12/28/2022]
Abstract
The past decade of research on Drosophila stem cells and niches has provided key insights. Fly stem cells do not occupy a special "state" based on novel "stem cell genes" but resemble transiently arrested tissue progenitors. Moreover, individual stem cells and downstream progenitors are highly dynamic and dispensable, not tissue bulwarks. Niches, rather than fixed cell lineages, ensure tissue health by holding stem cells and repressing cell differentiation inside, but not outside. We review the five best-understood adult Drosophila stem cells and argue that the fundamental biology of stem cells and niches is conserved between Drosophila and mice.
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Affiliation(s)
- Vicki P Losick
- Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution for Science, 3520 San Martin Drive, Baltimore, MD 21218, USA
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Abstract
In metazoans, tissue maintenance and regeneration depend on adult stem cells, which are characterized by their ability to self-renew and generate differentiating progeny in response to the needs of the tissues in which they reside. In the Drosophila testis, germline and somatic stem cells are housed together in a common niche, where they are regulated by local signals, epigenetic mechanisms and systemic factors. These stem cell populations in the Drosophila testis have the unique advantage of being easy to identify and manipulate, and hence much progress has been made in understanding how this niche operates. Here, we summarize recent work on stem cells in the adult Drosophila testis and discuss the remarkable ability of these stem cells to respond to change within the niche.
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Affiliation(s)
- Margaret de Cuevas
- Department of Cell Biology, Johns Hopkins School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
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Wang L, McLeod CJ, Jones DL. Regulation of adult stem cell behavior by nutrient signaling. Cell Cycle 2011; 10:2628-34. [PMID: 21814033 DOI: 10.4161/cc.10.16.17059] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Adult stem cells play an essential role throughout life, maintaining tissue and organ function by providing a reservoir of cells for homeostasis and repair. Maintenance and activity of adult stem cells have been the focus of numerous studies that have revealed stem cell-intrinsic factors and signals from the local microenvironment that regulate stem cell behavior. A growing body of work has provided evidence that circulating, systemic factors also contribute to the regulation of stem cell behavior in numerous tissues. We have demonstrated that Drosophila male germline stem cells (GSCs) and intestinal stem cells (ISCs) respond to changes in nutrient availability, specifically amino acids. Furthermore, we have shown that insulin signaling plays an important role in mediating the effects of changes in nutritional conditions. Notably, insulin signaling is cell-autonomously required within male GSCs for maintenance. Here we discuss our data regarding the effects and mechanisms by which changes in systemic nutritional conditions may influence the maintenance and activity of adult stem cells via insulin signaling.
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Affiliation(s)
- Lei Wang
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
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Okamoto N, Yamanaka N, Endo Y, Kataoka H, Mizoguchi A. Spatiotemporal patterns of IGF-like peptide expression in the silkmoth Bombyx mori predict its pleiotropic actions. Gen Comp Endocrinol 2011; 173:171-82. [PMID: 21641909 DOI: 10.1016/j.ygcen.2011.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 05/09/2011] [Accepted: 05/17/2011] [Indexed: 11/28/2022]
Abstract
In vertebrates, insulin-like growth factors (IGFs) play important roles in the regulation of growth and development. Although the principal source of circulating IGFs is the liver, IGFs are also secreted by many other tissues, functioning locally through paracrine/autocrine mechanism. In the silkmoth Bombyx mori, Bommo-IGF-like peptide (BIGFLP) is the functional counterpart of vertebrate IGFs and is mainly produced by the fat body, a functional equivalent of the vertebrate liver and adipocytes. However, its production by other tissues has not yet been analyzed. In this study, we systematically surveyed the BIGFLP-producing tissues and stages by means of immunohistochemistry, in situ hybridization and real-time quantitative RT-PCR, showing that BIGFLP is also produced by the neurosecretory cells in the brain, ovariole sheath and testis sheath, in a stage-specific manner. The BIGFLP-producing cells in the brain were identical to the cells that produce bombyxins, insulin-like peptides of B. mori, but the temporal expression patterns of both peptides were totally different. The BIGFLP gene expression in the sheaths of ovariole and testis were induced by ecdysteroid in vitro, similar to the expression in the fat body. A very high BIGFLP immunoreactivity was also found in the pupal nephrocytes, a functional equivalent of the glomerular podocytes in the vertebrate kidney, without the expression of the gene, suggesting that circulating BIGFLP is taken up and degraded by these tissues. Based on the present observations, the physiological functions of BIGFLP in B. mori development are discussed.
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Affiliation(s)
- Naoki Okamoto
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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Sheng XR, Matunis E. Live imaging of the Drosophila spermatogonial stem cell niche reveals novel mechanisms regulating germline stem cell output. Development 2011; 138:3367-76. [PMID: 21752931 DOI: 10.1242/dev.065797] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Adult stem cells modulate their output by varying between symmetric and asymmetric divisions, but have rarely been observed in living intact tissues. Germline stem cells (GSCs) in the Drosophila testis are anchored to somatic hub cells and were thought to exclusively undergo oriented asymmetric divisions, producing one stem cell that remains hub-anchored and one daughter cell displaced out of the stem cell-maintaining micro-environment (niche). We developed extended live imaging of the Drosophila testis niche, allowing us to track individual germline cells. Surprisingly, new wild-type GSCs are generated in the niche during steady-state tissue maintenance by a previously undetected event we term 'symmetric renewal', where interconnected GSC-daughter cell pairs swivel such that both cells contact the hub. We also captured GSCs undergoing direct differentiation by detaching from the hub. Following starvation-induced GSC loss, GSC numbers are restored by symmetric renewals. Furthermore, upon more severe (genetically induced) GSC loss, both symmetric renewal and de-differentiation (where interconnected spermatogonia fragment into pairs while moving towards then establishing contact with the hub) occur simultaneously to replenish the GSC pool. Thus, stereotypically oriented stem cell divisions are not always correlated with an asymmetric outcome in cell fate, and changes in stem cell output are governed by altered signals in response to tissue requirements.
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Affiliation(s)
- X Rebecca Sheng
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Abstract
Ageing is accompanied by a progressive decline in stem cell function, resulting in less effective tissue homeostasis and repair. Here we discuss emerging invertebrate models that provide insights into molecular pathways of age-related stem cell dysfunction in mammals, and we present various paradigms of how stem cell functionality changes with age, including impaired self-renewal and aberrant differentiation potential.
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