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Hounsell C, Fan Y. Death fuels growth: Emerging players bridging apoptosis and cell proliferation in Drosophila and beyond. Semin Cell Dev Biol 2025; 169:103602. [PMID: 40081300 DOI: 10.1016/j.semcdb.2025.103602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2024] [Revised: 02/18/2025] [Accepted: 02/23/2025] [Indexed: 03/16/2025]
Abstract
Tissue homeostasis relies on a delicate balance between cell death and proliferation. Apoptosis plays a key role not only in removing damaged cells but also in promoting tissue recovery through a process known as apoptosis-induced proliferation (AiP). This review highlights how caspases, c-Jun N-terminal Kinase (JNK), and Reactive Oxygen Species (ROS) bridge cell death and proliferation, as revealed through studies using Drosophila as a model organism. We also compare these findings with advances in other model systems and discuss their broader implications for tissue regeneration and tumorigenesis.
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Affiliation(s)
- Caitlin Hounsell
- University of Birmingham, School of Biosciences, Birmingham, B15 2TT, UK
| | - Yun Fan
- University of Birmingham, School of Biosciences, Birmingham, B15 2TT, UK.
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2
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Gomez‐Cardona E, Dehkordi MH, Van Baar K, Vitkauskaite A, Julien O, Fearnhead HO. An atlas of caspase cleavage events in differentiating muscle cells. Protein Sci 2024; 33:e5156. [PMID: 39180494 PMCID: PMC11344277 DOI: 10.1002/pro.5156] [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: 05/28/2024] [Revised: 08/02/2024] [Accepted: 08/11/2024] [Indexed: 08/26/2024]
Abstract
Executioner caspases, such as caspase-3, are known to induce apoptosis, but in other contexts, they can control very different fates, including cell differentiation and neuronal plasticity. While hundreds of caspase substrates are known to be specifically targeted during cell death, we know very little about how caspase activity brings about non-apoptotic fates. Here, we report the first proteome identification of cleavage events in C2C12 cells undergoing myogenic differentiation and its comparison to undifferentiated or dying C2C12 cells. These data have identified new caspase substrates, including caspase substrates specifically associated with differentiation, and show that caspases are regulating proteins involved in myogenesis in myotubes, several days after caspase-3 initiated differentiation. Cytoskeletal proteins emerged as a major group of non-apoptotic caspase substrates. We also identified proteins with well-established roles in muscle differentiation as substrates cleaved in differentiating cells.
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Affiliation(s)
- Erik Gomez‐Cardona
- Department of Biochemistry, Faculty of Medicine and DentistryUniversity of AlbertaAlbertaCanada
| | - Mahshid H. Dehkordi
- Pharmacology and Therapeutics, School of MedicineUniversity of GalwayGalwayIreland
| | - Kolden Van Baar
- Department of Biochemistry, Faculty of Medicine and DentistryUniversity of AlbertaAlbertaCanada
| | - Aiste Vitkauskaite
- Pharmacology and Therapeutics, School of MedicineUniversity of GalwayGalwayIreland
| | - Olivier Julien
- Department of Biochemistry, Faculty of Medicine and DentistryUniversity of AlbertaAlbertaCanada
| | - Howard O. Fearnhead
- Pharmacology and Therapeutics, School of MedicineUniversity of GalwayGalwayIreland
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3
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Ghorbani N, Yaghubi R, Davoodi J, Pahlavan S. How does caspases regulation play role in cell decisions? apoptosis and beyond. Mol Cell Biochem 2024; 479:1599-1613. [PMID: 37976000 DOI: 10.1007/s11010-023-04870-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 10/05/2023] [Indexed: 11/19/2023]
Abstract
Caspases are a family of cysteine proteases, and the key factors behind the cellular events which occur during apoptosis and inflammation. However, increasing evidence shows the non-conventional pro-survival action of apoptotic caspases in crucial processes. These cellular events include cell proliferation, differentiation, and migration, which may appear in the form of metastasis, and chemotherapy resistance in cancerous situations. Therefore, there should be a precise and strict control of caspases activity, perhaps through maintaining the threshold below the required levels for apoptosis. Thus, understanding the regulators of caspase activities that render apoptotic caspases as non-apoptotic is of paramount importance both mechanistically and clinically. Furthermore, the functions of apoptotic caspases are affected by numerous post-translational modifications. In the present mini-review, we highlight the various mechanisms that directly impact caspases with respect to their anti- or non-apoptotic functions. In this regard, post-translational modifications (PTMs), isoforms, subcellular localization, transient activity, substrate availability, substrate selection, and interaction-mediated regulations are discussed.
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Affiliation(s)
- Negar Ghorbani
- Department of Biochemistry, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Roham Yaghubi
- Department of Biotechnology, College of Science, University of Tehran, Tehran, Iran
| | - Jamshid Davoodi
- Department of Biochemistry, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
| | - Sara Pahlavan
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
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4
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Ghorbani N, Shiri M, Alian M, Yaghubi R, Shafaghi M, Hojjat H, Pahlavan S, Davoodi J. A Non-Apoptotic Pattern of Caspase-9/Caspase-3 Activation During Differentiation of Human Embryonic Stem Cells into Cardiomyocytes. Adv Biol (Weinh) 2024; 8:e2400026. [PMID: 38640919 DOI: 10.1002/adbi.202400026] [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: 01/15/2024] [Revised: 03/22/2024] [Indexed: 04/21/2024]
Abstract
In vitro studies have demonstrated that the differentiation of embryonic stem cells (ESCs) into cardiomyocytes requires activation of caspases through the mitochondrial pathway. These studies have relied on synthetic substrates for activity measurements, which can be misleading due to potential none-specific hydrolysis of these substrates by proteases other than caspases. Hence, caspase-9 and caspase-3 activation are investigated during the differentiation of human ESCs (hESCs) by directly assessing caspase-9 and -3 cleavage. Western blot reveals the presence of the cleaved caspase-9 prior to and during the differentiation of human ESCs (hESCs) into cardiomyocytes at early stages, which diminishes as the differentiation progresses, without cleavage and activation of endogenous procaspase-3. Activation of exogenous procaspase-3 by endogenous caspase-9 and subsequent cleavage of chromogenic caspase-3 substrate i.e. DEVD-pNA during the course of differentiation confirmes that endogenous caspase-9 has the potency to recognize and activate procaspase-3, but for reasons that are unknown to us fails to do so. These observations suggest the existence of distinct mechanisms of caspase regulation in differentiation as compared to apoptosis. Bioinformatics analysis suggests the presence of caspase-9 regulators, which may influence proteolytic function under specific conditions.
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Affiliation(s)
- Negar Ghorbani
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614335, Iran
| | - Mahshad Shiri
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, 1665659911, Iran
| | - Maedeh Alian
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614335, Iran
| | - Roham Yaghubi
- Department of Biotechnology, College of Science, University of Tehran, Tehran, 1417614411, Iran
| | - Mojtaba Shafaghi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, 1665659911, Iran
| | - Hamidreza Hojjat
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614335, Iran
| | - Sara Pahlavan
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, 1665659911, Iran
| | - Jamshid Davoodi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614335, Iran
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5
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Ameijeiras P, Capriotti N, Ons S, Oliveira PL, Sterkel M. eIF3 subunit M regulates blood meal digestion in Rhodnius prolixus affecting ecdysis, reproduction, and survival. INSECT SCIENCE 2023; 30:1282-1292. [PMID: 36621956 DOI: 10.1111/1744-7917.13174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
In triatomines, blood-feeding triggers many physiological processes including post embryonic development and reproduction. Different feeding habits, such as hematophagy, can shape gene functions to meet the challenges of each type of diet. The gut of blood-sucking insects faces particular challenges after feeding due to the quantity and the quality of the food ingested. A comparison of transcriptomic and proteomic data indicates that post transcriptional regulation of gene expression is crucial in the triatomine gut. It was proposed that eukaryotic translation initiation factor 3 subunit m (eIF3m) and eIF3e define 2 different eIF3 complexes with a distinct affinity for the different mRNAs, thus selecting the set of mRNAs to be translated and constituting a post transcriptional mode of regulation of gene expression. Because the eIF3m is mainly expressed in the gut, we evaluated its relevance in Rhodnius prolixus physiology through RNA interference-mediated gene silencing. The knockdown of eIF3m reduced the digestion rate, affecting the processes triggered by a blood meal. Its silencing inhibited molting and caused premature death in nymphs while impaired ovary development, oviposition and increased resistance to starvation in adult females. The survival of males after feeding (resistance to starvation) was not affected by eIF3m knockdown. The information regarding the eIF3m function in insects is scarce and the phenotypes observed in R. prolixus upon eIF3m silencing are different and more severe than those previously described in Drosophila melanogaster, indicating a pleiotropic role of this gene in triatomines.
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Affiliation(s)
- Pilar Ameijeiras
- Laboratorio de Neurobiología de Insectos (LNI), Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CENEXA, CONICET, La Plata, Buenos Aires, Argentina
| | - Natalia Capriotti
- Laboratorio de Neurobiología de Insectos (LNI), Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CENEXA, CONICET, La Plata, Buenos Aires, Argentina
| | - Sheila Ons
- Laboratorio de Neurobiología de Insectos (LNI), Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CENEXA, CONICET, La Plata, Buenos Aires, Argentina
| | - Pedro L Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
| | - Marcos Sterkel
- Laboratorio de Neurobiología de Insectos (LNI), Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CENEXA, CONICET, La Plata, Buenos Aires, Argentina
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6
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Sarić N, Hashimoto-Torii K, Jevtović-Todorović V, Ishibashi N. Nonapoptotic caspases in neural development and in anesthesia-induced neurotoxicity. Trends Neurosci 2022; 45:446-458. [PMID: 35491256 PMCID: PMC9117442 DOI: 10.1016/j.tins.2022.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/22/2022] [Indexed: 10/18/2022]
Abstract
Apoptosis, classically initiated by caspase pathway activation, plays a prominent role during normal brain development as well as in neurodegeneration. The noncanonical, nonlethal arm of the caspase pathway is evolutionarily conserved and has also been implicated in both processes, yet is relatively understudied. Dysregulated pathway activation during critical periods of neurodevelopment due to environmental neurotoxins or exposure to compounds such as anesthetics can have detrimental consequences for brain maturation and long-term effects on behavior. In this review, we discuss key molecular characteristics and roles of the noncanonical caspase pathway and how its dysregulation may adversely affect brain development. We highlight both genetic and environmental factors that regulate apoptotic and sublethal caspase responses and discuss potential interventions that target the noncanonical caspase pathway for developmental brain injuries.
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Affiliation(s)
- Nemanja Sarić
- Center for Neuroscience Research, Children's National Hospital, Washington, DC, USA
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's National Hospital, Washington, DC, USA; Department of Pediatrics, Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | | | - Nobuyuki Ishibashi
- Center for Neuroscience Research, Children's National Hospital, Washington, DC, USA; Department of Pediatrics, Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA; Children's National Heart Institute, Children's National Hospital, Washington, DC, USA.
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7
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Xu DC, Wang L, Yamada KM, Baena-Lopez LA. Non-apoptotic activation of Drosophila caspase-2/9 modulates JNK signaling, the tumor microenvironment, and growth of wound-like tumors. Cell Rep 2022; 39:110718. [PMID: 35443185 PMCID: PMC9082238 DOI: 10.1016/j.celrep.2022.110718] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 02/15/2022] [Accepted: 03/31/2022] [Indexed: 11/23/2022] Open
Abstract
Resistance to apoptosis due to caspase deregulation is considered one of the main hallmarks of cancer. However, the discovery of novel non-apoptotic caspase functions has revealed unknown intricacies about the interplay between these enzymes and tumor progression. To investigate this biological problem, we capitalized on a Drosophila tumor model with human relevance based on the simultaneous overactivation of the EGFR and the JAK/STAT signaling pathways. Our data indicate that widespread non-apoptotic activation of initiator caspases limits JNK signaling and facilitates cell fate commitment in these tumors, thus preventing the overgrowth and exacerbation of malignant features of transformed cells. Intriguingly, caspase activity also reduces the presence of macrophage-like cells with tumor-promoting properties in the tumor microenvironment. These findings assign tumor-suppressing activities to caspases independent of apoptosis, while providing molecular details to better understand the contribution of these enzymes to tumor progression.
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Affiliation(s)
- Derek Cui Xu
- Cell Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4370, USA; Sir William Dunn School of Pathology, University of Oxford, Oxford, Oxfordshire OX1 3RE, UK
| | - Li Wang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, Oxfordshire OX1 3RE, UK
| | - Kenneth M Yamada
- Cell Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4370, USA.
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8
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Dehkordi MH, Munn RGK, Fearnhead HO. Non-Canonical Roles of Apoptotic Caspases in the Nervous System. Front Cell Dev Biol 2022; 10:840023. [PMID: 35281082 PMCID: PMC8904960 DOI: 10.3389/fcell.2022.840023] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/04/2022] [Indexed: 11/13/2022] Open
Abstract
Caspases are a family of cysteine proteases that predominantly cleave their substrates after aspartic acid residues. Much of what we know of caspases emerged from investigation a highly conserved form of programmed cell death called apoptosis. This form of cell death is regulated by several caspases, including caspase-2, caspase-3, caspase-7, caspase-8 and caspase-9. However, these “killer” apoptotic caspases have emerged as versatile enzymes that play key roles in a wide range of non-apoptotic processes. Much of what we understand about these non-apoptotic roles is built on work investigating how “killer” caspases control a range of neuronal cell behaviors. This review will attempt to provide an up to date synopsis of these roles.
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Affiliation(s)
- Mahshid H. Dehkordi
- Pharmacology and Therapeutics, National University of Ireland Galway, Galway, Ireland
| | | | - Howard O. Fearnhead
- Pharmacology and Therapeutics, National University of Ireland Galway, Galway, Ireland
- *Correspondence: Howard O. Fearnhead,
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9
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Neuman SD, Lee AR, Selegue JE, Cavanagh AT, Bashirullah A. A novel function for Rab1 and Rab11 during secretory granule maturation. J Cell Sci 2021; 134:jcs259037. [PMID: 34342349 PMCID: PMC8353522 DOI: 10.1242/jcs.259037] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 06/29/2021] [Indexed: 01/15/2023] Open
Abstract
Regulated exocytosis is an essential process whereby specific cargo proteins are secreted in a stimulus-dependent manner. Cargo-containing secretory granules are synthesized in the trans-Golgi network (TGN); after budding from the TGN, granules undergo modifications, including an increase in size. These changes occur during a poorly understood process called secretory granule maturation. Here, we leverage the Drosophila larval salivary glands as a model to characterize a novel role for Rab GTPases during granule maturation. We find that secretory granules increase in size ∼300-fold between biogenesis and release, and loss of Rab1 or Rab11 reduces granule size. Surprisingly, we find that Rab1 and Rab11 localize to secretory granule membranes. Rab11 associates with granule membranes throughout maturation, and Rab11 recruits Rab1. In turn, Rab1 associates specifically with immature granules and drives granule growth. In addition to roles in granule growth, both Rab1 and Rab11 appear to have additional functions during exocytosis; Rab11 function is necessary for exocytosis, while the presence of Rab1 on immature granules may prevent precocious exocytosis. Overall, these results highlight a new role for Rab GTPases in secretory granule maturation.
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Affiliation(s)
| | | | | | | | - Arash Bashirullah
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
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10
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Arama E, Baena-Lopez LA, Fearnhead HO. Non-lethal message from the Holy Land: The first international conference on nonapoptotic roles of apoptotic proteins. FEBS J 2021; 288:2166-2183. [PMID: 32885609 DOI: 10.1111/febs.15547] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 08/20/2020] [Indexed: 12/01/2022]
Abstract
Apoptosis is a major form of programmed cell death (PCD) that eliminates unnecessary and potentially dangerous cells in all metazoan organisms, thus ensuring tissue homeostasis and many developmental processes. Accordingly, defects in the activation of the apoptotic pathway often pave the way to disease. After several decades of intensive research, the molecular details controlling the apoptosis program have largely been unraveled, as well as the regulatory mechanisms of caspase activation during apoptosis. Nevertheless, an ever-growing list of studies is suggesting the essential role of caspases and other apoptotic proteins in ensuring nonlethal cellular functions during normal development, tissue repair, and regeneration. Moreover, if deregulated, these novel nonapoptotic functions can also instigate diseases. The difficulty of identifying and manipulating the caspase-dependent nonlethal cellular processes (CDPs), as well as the nonlethal functions of other cell death proteins (NLF-CDPs), meant that CDPs and NLF-CDPs have been only curiosities within the apoptotic field; however, the recent technical advancements and the latest biological findings are assigning an unanticipated biological significance to these nonapoptotic functions. Here, we summarize the various talks presented in the first international conference fully dedicated to discuss CDPs and NFL-CDPs and named 'The Batsheva de Rothschild Seminar on Non-Apoptotic Roles of Apoptotic Proteins'. The conference was organized between September 22, 2019, and 25, 2019, by Eli Arama (Weizmann Institute of Science), Luis Alberto Baena-Lopez (University of Oxford), and Howard O. Fearnhead (NUI Galway) at the Weizmann Institute of Science in Israel, and hosted a large international group of researchers.
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Affiliation(s)
- Eli Arama
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | | | - Howard O Fearnhead
- Pharmacology and Therapeutics, Biomedical Sciences, Dangan, NUI Galway, Ireland
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11
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Neuman SD, Terry EL, Selegue JE, Cavanagh AT, Bashirullah A. Mistargeting of secretory cargo in retromer-deficient cells. Dis Model Mech 2021; 14:dmm.046417. [PMID: 33380435 PMCID: PMC7847263 DOI: 10.1242/dmm.046417] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 12/08/2020] [Indexed: 12/11/2022] Open
Abstract
Intracellular trafficking is a basic and essential cellular function required for delivery of proteins to the appropriate subcellular destination; this process is especially demanding in professional secretory cells, which synthesize and secrete massive quantities of cargo proteins via regulated exocytosis. The Drosophila larval salivary glands are composed of professional secretory cells that synthesize and secrete mucin proteins at the onset of metamorphosis. Using the larval salivary glands as a model system, we have identified a role for the highly conserved retromer complex in trafficking of secretory granule membrane proteins. We demonstrate that retromer-dependent trafficking via endosomal tubules is induced at the onset of secretory granule biogenesis, and that recycling via endosomal tubules is required for delivery of essential secretory granule membrane proteins to nascent granules. Without retromer function, nascent granules do not contain the proper membrane proteins; as a result, cargo from these defective granules is mistargeted to Rab7-positive endosomes, where it progressively accumulates to generate dramatically enlarged endosomes. Retromer complex dysfunction is strongly associated with neurodegenerative diseases, including Alzheimer's disease, characterized by accumulation of amyloid β (Aβ). We show that ectopically expressed amyloid precursor protein (APP) undergoes regulated exocytosis in salivary glands and accumulates within enlarged endosomes in retromer-deficient cells. These results highlight recycling of secretory granule membrane proteins as a critical step during secretory granule maturation and provide new insights into our understanding of retromer complex function in secretory cells. These findings also suggest that missorting of secretory cargo, including APP, may contribute to the progressive nature of neurodegenerative disease.
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Affiliation(s)
- Sarah D Neuman
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
| | - Erica L Terry
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
| | - Jane E Selegue
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
| | - Amy T Cavanagh
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
| | - Arash Bashirullah
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
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12
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Kabigting JET, Toyama Y. Interplay between caspase, Yes-associated protein, and mechanics: A possible switch between life and death? Curr Opin Cell Biol 2020; 67:141-146. [PMID: 33189987 DOI: 10.1016/j.ceb.2020.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 10/05/2020] [Accepted: 10/13/2020] [Indexed: 01/05/2023]
Abstract
Organism development requires fine-tuning of the cell number by apoptosis and cell division, as well as proper cell fate specification. These processes are achieved through the integration of intracellular signals and intercellular interactions with neighboring cells as well as the extracellular environment. Apoptosis, a form of cell death typically associated with development and homeostasis, is mainly regulated by the caspase family of proteases. Although caspases are known to initiate and execute apoptosis, it is also known that low caspase levels have a broad spectrum of nonapoptotic functions, including differentiation and organ growth. These different roles of caspases raise intriguing questions: how are caspase levels regulated and what defines the balance between life and death? In this review, we focus on some recent findings that highlight how nonlethal levels of caspase activity, transcriptional coregulator Yes-associated protein (YAP), and mechanical factors influence each other in determining cell fate. We further discuss a possibility that the mechanical signals encountered by cells could regulate the level of caspase activity by mechanics through YAP and, in turn, how this determines whether a cell is susceptible or resistant to undergoing apoptosis in response to cell death stimuli.
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Affiliation(s)
| | - Yusuke Toyama
- Mechanobiology Institute, Level 5, T-lab Building, 5A Engineering Drive 1, Singapore, 117411; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543.
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13
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Amcheslavsky A, Lindblad JL, Bergmann A. Transiently "Undead" Enterocytes Mediate Homeostatic Tissue Turnover in the Adult Drosophila Midgut. Cell Rep 2020; 33:108408. [PMID: 33238125 PMCID: PMC7754855 DOI: 10.1016/j.celrep.2020.108408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 10/05/2020] [Accepted: 10/28/2020] [Indexed: 01/12/2023] Open
Abstract
We reveal surprising similarities between homeostatic cell turnover in adult Drosophila midguts and "undead" apoptosis-induced compensatory proliferation (AiP) in imaginal discs. During undead AiP, immortalized cells signal for AiP, allowing its analysis. Critical for undead AiP is the Myo1D-dependent localization of the initiator caspase Dronc to the plasma membrane. Here, we show that Myo1D functions in mature enterocytes (ECs) to control mitotic activity of intestinal stem cells (ISCs). In Myo1D mutant midguts, many signaling events involved in AiP (ROS generation, hemocyte recruitment, and JNK signaling) are affected. Importantly, similar to AiP, Myo1D is required for membrane localization of Dronc in ECs. We propose that ECs destined to die transiently enter an undead-like state through Myo1D-dependent membrane localization of Dronc, which enables them to generate signals for ISC activity and their replacement. The concept of transiently "undead" cells may be relevant for other stem cell models in flies and mammals.
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Affiliation(s)
- Alla Amcheslavsky
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, Worcester, MA 01605, USA
| | - Jillian L Lindblad
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, Worcester, MA 01605, USA
| | - Andreas Bergmann
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, Worcester, MA 01605, USA.
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14
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Shu B, Zhang J, Veeran S, Zhong G. Pro-Apoptotic Function Analysis of the Reaper Homologue IBM1 in Spodoptera frugiperda. Int J Mol Sci 2020; 21:ijms21082729. [PMID: 32326478 PMCID: PMC7215429 DOI: 10.3390/ijms21082729] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/08/2020] [Accepted: 04/10/2020] [Indexed: 12/26/2022] Open
Abstract
As an important type of programmed cell death, apoptosis plays a critical role in lepidopteran insects in response to various internal and external stresses. It is controlled by a network of genes such as those encoding the inhibitor of apoptosis proteins. However, there are few studies on apoptosis-related genes in Spodoptera frugiperda. In this study, an orthologue to the Drosophila reaper gene, named Sf-IBM1, was identified from S. frugiperda, and a full-length sequence was obtained by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends PCR (RACE-PCR). The expression pattern of Sf-IBM1 was determined in different developmental stages and various tissues. Apoptotic stimuli including azadirachtin, camptothecin, and ultraviolet radiation (UV) induced the expression of Sf-IBM1 at both transcript and protein levels. Overexpression of Sf-IBM1 induced apoptosis in Sf9 cells, and the Sf-IBM1 protein was localized in mitochondria. The apoptosis induced by Sf-IBM1 could be blocked by the caspase universal inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK) and Sf-IAP1. Our results provide valuable information that should contribute to a better understanding of the molecular events that lead to apoptosis in lepidopterans.
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Affiliation(s)
- Benshui Shu
- Guangzhou City Key Laboratory of Subtropical Fruit Trees Outbreak Control, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China;
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, China; (J.Z.); (S.V.)
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Jingjing Zhang
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, China; (J.Z.); (S.V.)
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Sethuraman Veeran
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, China; (J.Z.); (S.V.)
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, China; (J.Z.); (S.V.)
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Correspondence: ; Tel.: +86-20-8528-0308; Fax: +86-20-8528-0203
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15
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Dronc-independent basal executioner caspase activity sustains Drosophila imaginal tissue growth. Proc Natl Acad Sci U S A 2019; 116:20539-20544. [PMID: 31548372 PMCID: PMC6789915 DOI: 10.1073/pnas.1904647116] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Caspase is the enzyme involved in cell death, and its activation via the apoptosome is thought to represent irreversible cellular destruction. Furthermore, accumulating evidence suggests increasingly diverse functions of caspase beyond apoptosis. Here, using Drosophila wing as a model, we reveal that the specific executioner caspases, Dcp-1 and Decay, promote, rather than suppress by inducing apoptosis, tissue growth. These executioner caspases act independently of initiator caspase Dronc and apoptosis. We further show that the caspase-mediated cleavage of Acinus is important for sustaining tissue growth. Our research highlights the importance of executioner caspase-mediated basal proteolytic cleavage of substrates during tissue growth, and the findings hint at the original function of caspase—not apoptosis, but basal proteolytic cleavages for cell vigor. Caspase is best known as an enzyme involved in programmed cell death, which is conserved among multicellular organisms. In addition to its role in cell death, caspase is emerging as an indispensable enzyme in a wide range of cellular functions, which have recently been termed caspase-dependent nonlethal cellular processes (CDPs). In this study, we examined the involvement of cell death signaling in tissue-size determination using Drosophila wing as a model. We found that the Drosophila executioner caspases Dcp-1 and Decay, but not Drice, promoted wing growth independently of apoptosis. Most of the reports on CDPs argue the importance of the spatiotemporal regulation of the initiator caspase, Dronc; however, this sublethal caspase function was independent of Dronc, suggesting a more diverse array of CDP regulatory mechanisms. Tagging of TurboID, an improved promiscuous biotin ligase that biotinylates neighboring proteins, to the C terminus of caspases revealed the differences among the neighbors of executioner caspases. Furthermore, we found that the cleavage of Acinus, a substrate of the executioner caspase, was important in promoting wing growth. These results demonstrate the importance of executioner caspase-mediated basal proteolytic cleavage of substrates in sustaining tissue growth. Given the existence of caspase-like DEVDase activity in a unicellular alga, our results likely highlight the original function of caspase—not cell death, but basal proteolytic cleavages for cell vigor.
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16
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Li M, Sun S, Priest J, Bi X, Fan Y. Characterization of TNF-induced cell death in Drosophila reveals caspase- and JNK-dependent necrosis and its role in tumor suppression. Cell Death Dis 2019; 10:613. [PMID: 31409797 PMCID: PMC6692325 DOI: 10.1038/s41419-019-1862-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 12/26/2022]
Abstract
Tumor-necrosis factor (TNF) and its superfamily members are pleiotropic cytokines. Activation of TNF can lead to distinct cellular outcomes including inflammation, cell survival, and different forms of cell death, such as apoptosis and necrosis in a context-dependent manner. However, our understanding of what determines the versatile functions of TNF is far from complete. Here, we examined the molecular mechanisms that distinguish the forms of cell death induced by Eiger (Egr), the sole homolog of TNF in Drosophila. We show that expression of Egr in the developing Drosophila eye simultaneously induces apoptosis and apoptosis-independent developmental defects indicated by cellular disorganization, both of which rely on the c-Jun N-terminal kinase (JNK) signaling activity. Intriguingly, when effector caspases DrICE and Dcp-1 are defective or inhibited, expression of Egr triggers necrosis which is characterized by loss of cell membrane integrity, translucent cytoplasm, and aggregation of cellular organelles. Moreover, such Egr-induced necrosis depends on the catalytic activity of the initiator caspase Dronc and the input from JNK signaling but is independent of their roles in apoptosis. Further mosaic analysis with mutants of scribble (scrib), an evolutionarily conserved tumor suppressor gene regulating cell polarity, suggests that Egr/JNK-mediated apoptosis and necrosis establish a two-layered defense system to inhibit the oncogenic growth of scrib mutant cells. Together, we have identified caspase- and JNK-dependent mechanisms underlying Egr-induced apoptosis versus necrosis and their fail-safe roles in tumor suppression in an intact organism in vivo.
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Affiliation(s)
- Mingli Li
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Shiyao Sun
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Jessica Priest
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Xiaolin Bi
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Yun Fan
- School of Biosciences, University of Birmingham, Birmingham, UK.
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17
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Fujisawa Y, Kosakamoto H, Chihara T, Miura M. Non-apoptotic function of Drosophila caspase activation in epithelial thorax closure and wound healing. Development 2019; 146:146/4/dev169037. [DOI: 10.1242/dev.169037] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 01/21/2019] [Indexed: 12/28/2022]
Abstract
ABSTRACT
Non-apoptotic caspase activation involves multiple cellular events. However, the link between visible non-apoptotic caspase activation and its function in living organisms has not yet been revealed. Here, we visualized sub-lethal activation of apoptotic signaling with the combination of a sensitive indicator for caspase 3 activation and in vivo live-imaging analysis of Drosophila. During thorax closure in pupal development, caspase 3 activation was specifically observed at the leading edge cells, with no signs of apoptosis. Inhibition of caspase activation led to an increase in thorax closing speed, which suggests a role of non-apoptotic caspase activity in cell motility. Importantly, sub-lethal activation of caspase 3 was also observed during wound closure at the fusion sites at which thorax closure had previously taken place. Further genetic analysis revealed that the activation of the initiator caspase Dronc is coupled with the generation of reactive oxygen species. The activation of Dronc also regulates myosin levels and delays wound healing. Our findings suggest a possible function for non-apoptotic caspase activation in the fine-tuning of cell migratory behavior during epithelial closure.
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Affiliation(s)
- Yuya Fujisawa
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hina Kosakamoto
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takahiro Chihara
- Department of Biological Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Masayuki Miura
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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18
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Two Sides of the Same Coin - Compensatory Proliferation in Regeneration and Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1167:65-85. [PMID: 31520349 DOI: 10.1007/978-3-030-23629-8_4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Apoptosis has long been regarded as a tumor suppressor mechanism and evasion from apoptosis is considered to be one hallmark of cancer. However, this principle is not always consistent with clinical data which often illustrate a correlation between apoptosis and poor prognosis. Work in the last 15 years has provided an explanation for this apparent paradox. Apoptotic cells communicate with their environment and can produce signals which promote compensatory proliferation of surviving cells. This behavior of apoptotic cells is important for tissue regeneration in several model organisms, ranging from hydra to mammals. However, it may also play an important feature for tumorigenesis and tumor relapse. Several distinct forms of apoptosis-induced compensatory proliferation (AiP) have been identified, many of which involve reactive oxygen species (ROS) and immune cells. One type of AiP, "undead" AiP, in which apoptotic cells are kept in an immortalized state and continuously divide, may have particular relevance for tumorigenesis. Furthermore, given that chemo- and radiotherapy often aim to kill tumor cells, an improved understanding of the effects of apoptotic cells on the tumor and the tumor environment is of critical importance for the well-being of the patient. In this review, we summarize the current knowledge of AiP and focus our attention on recent findings obtained in Drosophila and other model organisms, and relate them to tumorigenesis.
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19
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Baena-Lopez LA, Arthurton L, Bischoff M, Vincent JP, Alexandre C, McGregor R. Novel initiator caspase reporters uncover previously unknown features of caspase-activating cells. Development 2018; 145:dev170811. [PMID: 30413561 PMCID: PMC6288387 DOI: 10.1242/dev.170811] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/31/2018] [Indexed: 12/30/2022]
Abstract
The caspase-mediated regulation of many cellular processes, including apoptosis, justifies the substantial interest in understanding all of the biological features of these enzymes. To complement functional assays, it is crucial to identify caspase-activating cells in live tissues. Our work describes novel initiator caspase reporters that, for the first time, provide direct information concerning the initial steps of the caspase activation cascade in Drosophila tissues. One of our caspase sensors capitalises on the rapid subcellular localisation change of a fluorescent marker to uncover novel cellular apoptotic events relating to the actin-mediated positioning of the nucleus before cell delamination. The other construct benefits from caspase-induced nuclear translocation of a QF transcription factor. This feature enables the genetic manipulation of caspase-activating cells and reveals the spatiotemporal patterns of initiator caspase activity. Collectively, our sensors offer experimental opportunities not available by using previous reporters and have proven useful to illuminate previously unknown aspects of caspase-dependent processes in apoptotic and non-apoptotic cellular scenarios.
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Affiliation(s)
- Luis Alberto Baena-Lopez
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxfordshire, OX1 3RE, UK
| | - Lewis Arthurton
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxfordshire, OX1 3RE, UK
| | - Marcus Bischoff
- Biomolecular Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, Scotland, KY16 9ST, UK
| | | | | | - Reuben McGregor
- Faculty of Medical and Health Sciences, Molecular Medicine & Pathology, The University of Auckland, M&HS Building 502, 85 Park Road, Grafton, Auckland 1023, New Zealand
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20
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Su TT. Cellular plasticity, caspases and autophagy; that which does not kill us, well, makes us different. Open Biol 2018; 8:rsob.180157. [PMID: 30487302 PMCID: PMC6282069 DOI: 10.1098/rsob.180157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 10/30/2018] [Indexed: 02/07/2023] Open
Abstract
The ability to regenerate is a fundamental requirement for tissue homeostasis. Regeneration draws on three sources of cells. First and best-studied are dedicated stem/progenitor cells. Second, existing cells may proliferate to compensate for the lost cells of the same type. Third, a different cell type may change fate to compensate for the lost cells. This review focuses on regeneration of the third type and will discuss the contributions by post-transcriptional mechanisms including the emerging evidence for cell-autonomous and non-lethal roles of cell death pathways.
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Affiliation(s)
- Tin Tin Su
- Department of Molecular, Cellular and Developmental Biology, 347 UCB, University of Colorado, Boulder, CO 80309-0347, USA .,University of Colorado Comprehensive Cancer Center, Anschutz Medical Campus, 13001 E. 17th Pl., Aurora, CO 80045, USA
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21
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Yalonetskaya A, Mondragon AA, Elguero J, McCall K. I Spy in the Developing Fly a Multitude of Ways to Die. J Dev Biol 2018; 6:E26. [PMID: 30360387 PMCID: PMC6316796 DOI: 10.3390/jdb6040026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 12/11/2022] Open
Abstract
Cell proliferation and cell death are two opposing, yet complementary fundamental processes in development. Cell proliferation provides new cells, while developmental programmed cell death adjusts cell numbers and refines structures as an organism grows. Apoptosis is the best-characterized form of programmed cell death; however, there are many other non-apoptotic forms of cell death that occur throughout development. Drosophila is an excellent model for studying these varied forms of cell death given the array of cellular, molecular, and genetic techniques available. In this review, we discuss select examples of apoptotic and non-apoptotic cell death that occur in different tissues and at different stages of Drosophila development. For example, apoptosis occurs throughout the nervous system to achieve an appropriate number of neurons. Elsewhere in the fly, non-apoptotic modes of developmental cell death are employed, such as in the elimination of larval salivary glands and midgut during metamorphosis. These and other examples discussed here demonstrate the versatility of Drosophila as a model organism for elucidating the diverse modes of programmed cell death.
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Affiliation(s)
- Alla Yalonetskaya
- Cell and Molecular Biology Program, Department of Biology, 5 Cummington Mall, Boston University, Boston, MA 02215, USA.
| | - Albert A Mondragon
- Molecular Biology, Cell Biology, and Biochemistry Program, 5 Cummington Mall, Boston University, Boston, MA 02215, USA.
| | - Johnny Elguero
- Cell and Molecular Biology Program, Department of Biology, 5 Cummington Mall, Boston University, Boston, MA 02215, USA.
| | - Kimberly McCall
- Cell and Molecular Biology Program, Department of Biology, 5 Cummington Mall, Boston University, Boston, MA 02215, USA.
- Molecular Biology, Cell Biology, and Biochemistry Program, 5 Cummington Mall, Boston University, Boston, MA 02215, USA.
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22
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Neuman SD, Bashirullah A. Hobbit regulates intracellular trafficking to drive insulin-dependent growth during Drosophila development. Development 2018; 145:dev161356. [PMID: 29891564 PMCID: PMC6031322 DOI: 10.1242/dev.161356] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 05/08/2018] [Indexed: 12/17/2022]
Abstract
All animals must coordinate growth rate and timing of maturation to reach the appropriate final size. Here, we describe hobbit, a novel and conserved gene identified in a forward genetic screen for Drosophila animals with small body size. hobbit is highly conserved throughout eukaryotes, but its function remains unknown. We demonstrate that hobbit mutant animals have systemic growth defects because they fail to secrete insulin. Other regulated secretion events also fail in hobbit mutant animals, including mucin-like 'glue' protein secretion from the larval salivary glands. hobbit mutant salivary glands produce glue-containing secretory granules that are reduced in size. Importantly, secretory granules in hobbit mutant cells lack essential membrane fusion machinery required for exocytosis, including Synaptotagmin 1 and the SNARE SNAP-24. These membrane fusion proteins instead accumulate inside enlarged late endosomes. Surprisingly, however, the Hobbit protein localizes to the endoplasmic reticulum. Our results suggest that Hobbit regulates a novel step in intracellular trafficking of membrane fusion proteins. Our studies also suggest that genetic control of body size, as a measure of insulin secretion, is a sensitive functional readout of the secretory machinery.
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Affiliation(s)
- Sarah D Neuman
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
- Cellular and Molecular Biology Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Arash Bashirullah
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI 53705-2222, USA
- Cellular and Molecular Biology Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
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23
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Amcheslavsky A, Wang S, Fogarty CE, Lindblad JL, Fan Y, Bergmann A. Plasma Membrane Localization of Apoptotic Caspases for Non-apoptotic Functions. Dev Cell 2018; 45:450-464.e3. [PMID: 29787709 PMCID: PMC5972739 DOI: 10.1016/j.devcel.2018.04.020] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 03/20/2018] [Accepted: 04/20/2018] [Indexed: 12/19/2022]
Abstract
Caspases are best characterized for their function in apoptosis. However, they also have non-apoptotic functions such as apoptosis-induced proliferation (AiP), where caspases release mitogens for compensatory proliferation independently of their apoptotic role. Here, we report that the unconventional myosin, Myo1D, which is known for its involvement in left/right development, is an important mediator of AiP in Drosophila. Mechanistically, Myo1D translocates the initiator caspase Dronc to the basal side of the plasma membrane of epithelial cells where Dronc promotes the activation of the NADPH-oxidase Duox for reactive oxygen species generation and AiP in a non-apoptotic manner. We propose that the basal side of the plasma membrane constitutes a non-apoptotic compartment for caspases. Finally, Myo1D promotes tumor growth and invasiveness of the neoplastic scrib RasV12 model. Together, we identified a new function of Myo1D for AiP and tumorigenesis, and reveal a mechanism by which cells sequester apoptotic caspases in a non-apoptotic compartment at the plasma membrane.
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Affiliation(s)
- Alla Amcheslavsky
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, 364 Plantation Street, Worcester, MA 01605, USA
| | - Shiuan Wang
- Baylor College of Medicine, Program in Developmental Biology, Houston, TX 77030, USA
| | - Caitlin E Fogarty
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, 364 Plantation Street, Worcester, MA 01605, USA
| | - Jillian L Lindblad
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, 364 Plantation Street, Worcester, MA 01605, USA
| | - Yun Fan
- University of Birmingham, School of Biosciences, Edgbaston, Birmingham B15 2TT, UK
| | - Andreas Bergmann
- University of Massachusetts Medical School, Department of Molecular, Cell and Cancer Biology, 364 Plantation Street, Worcester, MA 01605, USA.
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