1
|
Hof-Michel S, Cigoja L, Huhn S, Bökel C. Rel governs loser elimination during stem cell competition in the Drosophila testis. Eur J Cell Biol 2024; 103:151375. [PMID: 37995529 DOI: 10.1016/j.ejcb.2023.151375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
In the Drosophila testis, a group of stromal cells termed hub provides multiple niche signals for the surrounding germline and somatic stem cells. Stem cells of both populations compete for physical retention in the niche, and clones unable to transduce any one niche signal are rapidly eliminated from the stem cell pool by differentiation. We have mapped the transcriptomes of isolated somatic cyst stem cells and differentiated cyst cells, and found that the stem cells but not their differentiated progeny exhibit the signature of an innate immune response including the NF-κB transcription factor Relish (Rel). Related signalling pathways had previously implicated in cell competition in larval epithelia, prompting the question of whether NF-κB signalling was, despite the clear differences between the two competition scenarios, also involved in stem cell competition in the testis. Here we show i) that in the testis Rel is dispensable for stemness, ii) that loss of Rel or the upstream receptor Toll suppresses loser elimination following a variety of different triggers used to induce loser fate, and iii) that clonal Rel activation is sufficient for the displacement of neutral or winner cells from the niche, even if these cells otherwise retain stem cell properties.
Collapse
Affiliation(s)
- Silvana Hof-Michel
- Dept. of Developmental Genetics, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35043 Marburg, Germany
| | - Ljubinka Cigoja
- Dept. of Developmental Genetics, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35043 Marburg, Germany
| | - Sabina Huhn
- Dept. of Developmental Genetics, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35043 Marburg, Germany
| | - Christian Bökel
- Core Facility Confocal and Multiphoton Microscopy, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| |
Collapse
|
2
|
Huang WH, Kajal K, Wibowo RH, Amartuvshin O, Kao SH, Rastegari E, Lin CH, Chiou KL, Pi HW, Ting CT, Hsu HJ. Excess dietary sugar impairs Drosophila adult stem cells via elevated reactive oxygen species-induced JNK signaling. Development 2024; 151:dev201772. [PMID: 38063853 DOI: 10.1242/dev.201772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 11/24/2023] [Indexed: 01/03/2024]
Abstract
High-sugar diets (HSDs) often lead to obesity and type 2 diabetes, both metabolic syndromes associated with stem cell dysfunction. However, it is unclear whether excess dietary sugar affects stem cells. Here, we report that HSD impairs stem cell function in the intestine and ovaries of female Drosophila prior to the onset of insulin resistance, a hallmark of type 2 diabetes. Although 1 week of HSD leads to obesity, impaired oogenesis and altered lipid metabolism, insulin resistance does not occur. HSD increases glucose uptake by germline stem cells (GSCs) and triggers reactive oxygen species-induced JNK signaling, which reduces GSC proliferation. Removal of excess sugar from the diet reverses these HSD-induced phenomena. A similar phenomenon is found in intestinal stem cells (ISCs), except that HSD disrupts ISC maintenance and differentiation. Interestingly, tumor-like GSCs and ISCs are less responsive to HSD, which may be because of their dependence on glycolytic metabolism and high energy demand, respectively. This study suggests that excess dietary sugar induces oxidative stress and damages stem cells before insulin resistance develops, a mechanism that may also occur in higher organisms.
Collapse
Affiliation(s)
- Wei-Hao Huang
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
- Department of Life Science, National Taiwan University, Taipei 10917
| | - Kreeti Kajal
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
- Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227
| | | | - Oyundari Amartuvshin
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529
- Graduate Institute of Life Science, National Defense Medical Center, Taipei 11490
| | - Shih-Han Kao
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
| | - Elham Rastegari
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
| | - Chi-Hung Lin
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529
- Graduate Institute of Life Science, National Defense Medical Center, Taipei 11490
| | - Kuan-Lin Chiou
- Department of Biomedical Science, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Hai-Wei Pi
- Department of Biomedical Science, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Chau-Ti Ting
- Department of Life Science, National Taiwan University, Taipei 10917
| | - Hwei-Jan Hsu
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529
| |
Collapse
|
3
|
Ayachit MS, Shravage BV. Atg1 modulates mitochondrial dynamics to promote germline stem cell maintenance in Drosophila. Biochem Biophys Res Commun 2023; 643:192-202. [PMID: 36621115 DOI: 10.1016/j.bbrc.2022.11.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/11/2022] [Accepted: 11/24/2022] [Indexed: 12/05/2022]
Abstract
Mitochondrial dynamics (fusion and fission) are necessary for stem cell maintenance and differentiation. However, the relationship between mitophagy, mitochondrial dynamics and stem cell exhaustion needs to be clearly understood. Here we report the multifaceted role of Atg1 in mitophagy, mitochondrial dynamics and stem cell maintenance in female germline stem cells (GSCs) in Drosophila. We found that depletion of Atg1 in GSCs leads to impaired autophagy and mitophagy as measured by reduced formation of autophagosomes, increased accumulation of p62/Ref (2)P and accumulation of damaged mitochondria. Disrupting Atg1 function led to mitochondrial fusion in developing cysts. The fusion resulted from an increase in Marf levels in both GSCs and cysts, and the fusion phenotype could be rescued by overexpression of Drp1 or by depleting Marf via RNAi in Atg1-depleted cyst cells. Interestingly, double knockdown of both Atg1:Drp1 led to the significant loss of germ cells (GCs) as compared to Atg1KD and Drp1KD. Strikingly, Atg1:Marf double knockdown leads to a dramatic loss of GSCs, GCs and a total loss of vitellogenic stages, suggesting a block in oogenesis. Overall, our results demonstrate that Drp1, Marf and Atg1 function together to influence female GSC maintenance, their differentiation into cysts and oogenesis in Drosophila.
Collapse
Affiliation(s)
- Minal S Ayachit
- Developmental Biology Group, MACS-Agharkar Research Institute, Gopal Ganesh Agarkar Road, Pune, 411004, India; Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India
| | - Bhupendra V Shravage
- Developmental Biology Group, MACS-Agharkar Research Institute, Gopal Ganesh Agarkar Road, Pune, 411004, India; Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007, India.
| |
Collapse
|
4
|
Zhao H, Long S, Liu S, Yuan D, Huang D, Xu J, Ma Q, Wang G, Wang J, Li S, Tian L, Li K. Atg1 phosphorylation is activated by AMPK and indispensable for autophagy induction in insects. Insect Biochem Mol Biol 2023; 152:103888. [PMID: 36493962 DOI: 10.1016/j.ibmb.2022.103888] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/14/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Phosphorylation is a key post-translational modification in regulating autophagy in yeast and mammalians, yet it is not fully illustrated in invertebrates such as insects. ULK1/Atg1 is a functionally conserved serine/threonine protein kinase involved in autophagosome initiation. As a result of alternative splicing, Atg1 in the silkworm, Bombyx mori, is present as three mRNA isoforms, with BmAtg1c showing the highest expression levels. Here, we found that BmAtg1c mRNA expression, BmAtg1c protein expression and phosphorylation, and autophagy simultaneously peaked in the fat body during larval-pupal metamorphosis. Importantly, two BmAtg1c phosphorylation sites were identified at Ser269 and Ser270, which were activated by BmAMPK, the major energy-sensing kinase, upon stimulation with 20-hydroxyecdysone and starvation; additionally, these Atg1 phosphorylation sites are evolutionarily conserved in insects. The two BmAMPK-activated phosphorylation sites in BmAtg1c were found to be required for BmAMPK-induced autophagy. Moreover, the two corresponding DmAtg1 phosphorylation sites in the fruit fly, Drosophila melanogaster, are functionally conserved for autophagy induction. In conclusion, AMPK-activated Atg1 phosphorylation is indispensable for autophagy induction and evolutionarily conserved in insects, shedding light on how various groups of organisms differentially regulate ULK1/Atg1 phosphorylation for autophagy induction.
Collapse
Affiliation(s)
- Haigang Zhao
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Key Laboratory of Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China; University of Chinese Academy of Sciences, Beijing, 100049, China; School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; ChemPartner PharmaTech Co., Ltd, Jiangmen, 529081, China; Quantum Hi-Tech (Guangdong) Biological Co., Ltd, Jiangmen, 529081, China
| | - Shihui Long
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Suning Liu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Dongwei Yuan
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Key Laboratory of Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Danyan Huang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jing Xu
- Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China
| | - Qiuqin Ma
- Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China
| | - Guirong Wang
- Guangdong Laboratory for Lingnan Modern Agriculture (Shenzhen Branch), Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Jian Wang
- Department of Entomology, University of Maryland, College Park, MD, 20742, USA
| | - Sheng Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China; Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou, 514779, China
| | - Ling Tian
- Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China.
| | - Kang Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China; Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou, 514779, China.
| |
Collapse
|
5
|
Kobayashi H. Recent advances in understanding the metabolic plasticity of ovarian cancer: A systematic review. Heliyon 2022; 8:e11487. [PMID: 36406733 PMCID: PMC9668530 DOI: 10.1016/j.heliyon.2022.e11487] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/03/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022] Open
Abstract
Epithelial ovarian cancer (EOC) is a gynecologic malignancy with a poor prognosis due to resistance to first-line chemotherapeutic agents. Some cancer cells are primarily dependent on glycolysis, but others favor mitochondrial oxidative phosphorylation (OXPHOS) over glycolysis. Changes in metabolic reprogramming have been reported to be involved in cancer cell survival. In this review, we summarize the metabolic profiles (e.g., metabolic heterogeneity, plasticity, and reprogramming) and adaptation to the dynamic tumor microenvironment and discuss potential novel therapeutic strategies. A literature search was performed between January 2000 and March 2022 in the PubMed and Google Scholar databases using a combination of specific terms. Ovarian cancer cells, including cancer stem cells, depend on glycolysis, OXPHOS, or both for survival. Several environmental stresses, such as nutrient starvation or glucose deprivation, hypoxic stress, acidification, and excessive reactive oxygen species (ROS) generation, reprogram the metabolic pathways to adapt. The interaction between tumors and adjacent stromal cells allows cancer cells to enhance mitochondrial energy metabolism. The metabolic reprogramming varies depending on genomic and epigenetic alterations of metabolism-related genes and the metabolic environment. Developing accurate and non-invasive methods for early identification of metabolic alterations could facilitate optimal cancer diagnosis and treatment. Cancer metabolism research has entered an exciting era where novel strategies targeting metabolic profiling will become more innovative.
Collapse
|
6
|
Varga VB, Schuller D, Szikszai F, Szinyákovics J, Puska G, Vellai T, Kovács T. Autophagy is required for spermatogonial differentiation in the Drosophila testis. Biol Futur. [DOI: 10.1007/s42977-022-00122-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 05/13/2022] [Indexed: 10/18/2022]
Abstract
AbstractAutophagy is a conserved, lysosome-dependent catabolic process of eukaryotic cells which is involved in cellular differentiation. Here, we studied its specific role in the differentiation of spermatogonial cells in the Drosophila testis. In the apical part of the Drosophila testis, there is a niche of germline stem cells (GSCs), which are connected to hub cells. Hub cells emit a ligand for bone morhphogenetic protein (BMP)-mediated signalling that represses Bam (bag of marbles) expression in GSCs to maintain them in an undifferentiated state. GSCs divide asymmetrically, and one of the daughter cells differentiates into a gonialblast, which eventually generates a cluster of spermatogonia (SG) by mitoses. Bam is active in SG, and defects in Bam function arrest these cells at mitosis. We show that BMP signalling represses autophagy in GSCs, but upregulates the process in SG. Inhibiting autophagy in SG results in an overproliferating phenotype similar to that caused by bam mutations. Furthermore, Bam deficiency leads to a failure in downstream mechanisms of the autophagic breakdown. These results suggest that the BMP-Bam signalling axis regulates developmental autophagy in the Drosophila testis, and that acidic breakdown of cellular materials is required for spermatogonial differentiation.
Collapse
|
7
|
Lin TH, Bis-Brewer DM, Sheehan AE, Townsend LN, Maddison DC, Züchner S, Smith GA, Freeman MR. TSG101 negatively regulates mitochondrial biogenesis in axons. Proc Natl Acad Sci U S A 2021; 118. [PMID: 33972422 DOI: 10.1073/pnas.2018770118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
There is a tight association between mitochondrial dysfunction and neurodegenerative diseases and axons that are particularly vulnerable to degeneration, but how mitochondria are maintained in axons to support their physiology remains poorly defined. In an in vivo forward genetic screen for mutants altering axonal mitochondria, we identified tsg101 Neurons mutant for tsg101 exhibited an increase in mitochondrial number and decrease in mitochondrial size. TSG101 is best known as a component of the endosomal sorting complexes required for transport (ESCRT) complexes; however, loss of most other ESCRT components did not affect mitochondrial numbers or size, suggesting TSG101 regulates mitochondrial biology in a noncanonical, ESCRT-independent manner. The TSG101-mutant phenotype was not caused by lack of mitophagy, and we found that autophagy blockade was detrimental only to the mitochondria in the cell bodies, arguing mitophagy and autophagy are dispensable for the regulation of mitochondria number in axons. Interestingly, TSG101 mitochondrial phenotypes were instead caused by activation of PGC-1ɑ/Nrf2-dependent mitochondrial biogenesis, which was mTOR independent and TFEB dependent and required the mitochondrial fission-fusion machinery. Our work identifies a role for TSG101 in inhibiting mitochondrial biogenesis, which is essential for the maintenance of mitochondrial numbers and sizes, in the axonal compartment.
Collapse
|
8
|
Formica M, Storaci AM, Bertolini I, Carminati F, Knævelsrud H, Vaira V, Vaccari T. V-ATPase controls tumor growth and autophagy in a Drosophila model of gliomagenesis. Autophagy 2021; 17:4442-4452. [PMID: 33978540 PMCID: PMC8726678 DOI: 10.1080/15548627.2021.1918915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Glioblastoma (GBM), a very aggressive and incurable tumor, often results from constitutive activation of EGFR (epidermal growth factor receptor) and of phosphoinositide 3-kinase (PI3K). To understand the role of autophagy in the pathogenesis of glial tumors in vivo, we used an established Drosophila melanogaster model of glioma based on overexpression in larval glial cells of an active human EGFR and of the PI3K homolog Pi3K92E/Dp110. Interestingly, the resulting hyperplastic glia express high levels of key components of the lysosomal-autophagic compartment, including vacuolar-type H+-ATPase (V-ATPase) subunits and ref(2)P (refractory to Sigma P), the Drosophila homolog of SQSTM1/p62. However, cellular clearance of autophagic cargoes appears inhibited upstream of autophagosome formation. Remarkably, downregulation of subunits of V-ATPase, of Pdk1, or of the Tor (Target of rapamycin) complex 1 (TORC1) component raptor prevents overgrowth and normalize ref(2)P levels. In addition, downregulation of the V-ATPase subunit VhaPPA1-1 reduces Akt and Tor-dependent signaling and restores clearance. Consistent with evidence in flies, neurospheres from patients with high V-ATPase subunit expression show inhibition of autophagy. Altogether, our data suggest that autophagy is repressed during glial tumorigenesis and that V-ATPase and MTORC1 components acting at lysosomes could represent therapeutic targets against GBM.
Collapse
Affiliation(s)
- Miriam Formica
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy
| | - Alessandra Maria Storaci
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università Degli Studi Di Milano, Milan, Italy
| | - Irene Bertolini
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università Degli Studi Di Milano, Milan, Italy
| | | | - Helene Knævelsrud
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, the Norwegian Radium Hospital, Oslo, Norway.,Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Valentina Vaira
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università Degli Studi Di Milano, Milan, Italy
| | - Thomas Vaccari
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy
| |
Collapse
|
9
|
Duan X, Tong C. Autophagy in Drosophila and Zebrafish. Adv Exp Med Biol 2021; 1208:333-356. [PMID: 34260032 DOI: 10.1007/978-981-16-2830-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved cellular process that delivers cellular contents to the lysosome for degradation. It not only serves as a bulk degradation system for various cytoplasmic components but also functions selectively to clear damaged organelles, aggregated proteins, and invading pathogens (Feng et al., Cell Res 24:24-41, 2014; Galluzzi et al., EMBO J 36:1811-36, 2017; Klionsky et al., Autophagy 12:1-222, 2016). The malfunction of autophagy leads to multiple developmental defects and diseases (Mizushima et al., Nature 451:1069-75, 2008). Drosophila and zebrafish are higher metazoan model systems with sophisticated genetic tools readily available, which make it possible to dissect the autophagic processes and to understand the physiological functions of autophagy (Lorincz et al., Cells 6:22, 2017a; Mathai et al., Cells 6:21, 2017; Zhang and Baehrecke, Trends Cell Biol 25:376-87, 2015). In this chapter, we will discuss recent progress that has been made in the autophagic field by using these animal models. We will focus on the protein machineries required for autophagosome formation and maturation as well as the physiological roles of autophagy in both Drosophila and zebrafish.
Collapse
Affiliation(s)
- Xiuying Duan
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chao Tong
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China. .,The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
| |
Collapse
|
10
|
Madan E, Peixoto ML, Dimitrion P, Eubank TD, Yekelchyk M, Talukdar S, Fisher PB, Mi QS, Moreno E, Gogna R. Cell Competition Boosts Clonal Evolution and Hypoxic Selection in Cancer. Trends Cell Biol 2020; 30:967-978. [PMID: 33160818 DOI: 10.1016/j.tcb.2020.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/01/2020] [Accepted: 10/05/2020] [Indexed: 12/17/2022]
Abstract
The comparison of fitness between cells leads to the elimination of less competent cells in the presence of more competent neighbors via cell competition (CC). This phenomenon has been linked with several cancer-related genes and thus may play an important role in cancer. Various processes are involved in the regulation of tumor initiation and growth, including tumor hypoxia, clonal stem cell selection, and immune cell response, all of which have been recently shown to have a potential connection with the mechanisms involved in CC. This review aims to unravel the relation between these processes and competitive cell interactions and how this affects disease progression.
Collapse
Affiliation(s)
- Esha Madan
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
| | | | - Peter Dimitrion
- Center for Cutaneous Biology and Immunology, Department of Dermatology, Henry Ford Health System, Detroit, MI, USA; Immunology Research Program, Henry Ford Cancer Institute, Henry Ford Health System, Detroit, MI, USA; Department of Biochemistry, Microbiology and Immunology, Wayne State University Medical School, Detroit, MI, USA
| | - Timothy D Eubank
- In Vivo Multifunctional Magnetic Resonance Center, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA; Department of Microbiology, Immunology, and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, USA
| | - Michail Yekelchyk
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Sarmistha Talukdar
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, VA, USA; VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, VA, USA
| | - Paul B Fisher
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, VA, USA; VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, VA, USA
| | - Qing-Sheng Mi
- Center for Cutaneous Biology and Immunology, Department of Dermatology, Henry Ford Health System, Detroit, MI, USA; Immunology Research Program, Henry Ford Cancer Institute, Henry Ford Health System, Detroit, MI, USA; Department of Biochemistry, Microbiology and Immunology, Wayne State University Medical School, Detroit, MI, USA
| | - Eduardo Moreno
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal.
| | - Rajan Gogna
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal.
| |
Collapse
|
11
|
Amartuvshin O, Lin C, Hsu S, Kao S, Chen A, Tang W, Chou H, Chang D, Hsu Y, Hsiao B, Rastegari E, Lin K, Wang Y, Yao C, Chen G, Chen B, Hsu H. Aging shifts mitochondrial dynamics toward fission to promote germline stem cell loss. Aging Cell 2020; 19:e13191. [PMID: 32666649 PMCID: PMC7431834 DOI: 10.1111/acel.13191] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 05/20/2020] [Accepted: 06/16/2020] [Indexed: 12/11/2022] Open
Abstract
Changes in mitochondrial dynamics (fusion and fission) are known to occur during stem cell differentiation; however, the role of this phenomenon in tissue aging remains unclear. Here, we report that mitochondrial dynamics are shifted toward fission during aging of Drosophila ovarian germline stem cells (GSCs), and this shift contributes to aging-related GSC loss. We found that as GSCs age, mitochondrial fragmentation and expression of the mitochondrial fission regulator, Dynamin-related protein (Drp1), are both increased, while mitochondrial membrane potential is reduced. Moreover, preventing mitochondrial fusion in GSCs results in highly fragmented depolarized mitochondria, decreased BMP stemness signaling, impaired fatty acid metabolism, and GSC loss. Conversely, forcing mitochondrial elongation promotes GSC attachment to the niche. Importantly, maintenance of aging GSCs can be enhanced by suppressing Drp1 expression to prevent mitochondrial fission or treating with rapamycin, which is known to promote autophagy via TOR inhibition. Overall, our results show that mitochondrial dynamics are altered during physiological aging, affecting stem cell homeostasis via coordinated changes in stemness signaling, niche contact, and cellular metabolism. Such effects may also be highly relevant to other stem cell types and aging-induced tissue degeneration.
Collapse
Affiliation(s)
- Oyundari Amartuvshin
- Molecular and Cell BiologyTaiwan International Graduate ProgramAcademia SinicaTaipeiTaiwan
- Graduate Institute of Life ScienceNational Defense Medical CenterTaipeiTaiwan
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Chi‐Hung Lin
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Shao‐Chun Hsu
- Imaging Core Facility at the Institute of Cellular and Organismic BiologyAcademia SinicaTaipeiTaiwan
| | - Shih‐Han Kao
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
- Present address:
Institute of ChemistryAcademia SinicaTaipeiTaiwan
| | - Alvin Chen
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Wei‐Chun Tang
- Research Center for Applied ScienceAcademia SinicaTaipeiTaiwan
| | - Han‐Lin Chou
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Dong‐Lin Chang
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
- The Affiliated Senior High School of National Taiwan Normal UniversityTaipeiTaiwan
| | - Yen‐Yang Hsu
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
- The Affiliated Senior High School of National Taiwan Normal UniversityTaipeiTaiwan
| | - Bai‐Shiou Hsiao
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
- The Affiliated Senior High School of National Taiwan Normal UniversityTaipeiTaiwan
| | | | - Kun‐Yang Lin
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Yu‐Ting Wang
- Molecular and Cell BiologyTaiwan International Graduate ProgramAcademia SinicaTaipeiTaiwan
- Graduate Institute of Life ScienceNational Defense Medical CenterTaipeiTaiwan
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| | - Chi‐Kuang Yao
- Institute of Biological ChemistryAcademia SinicaTaipeiTaiwan
| | - Guang‐Chao Chen
- Institute of Biological ChemistryAcademia SinicaTaipeiTaiwan
| | - Bi‐Chang Chen
- Research Center for Applied ScienceAcademia SinicaTaipeiTaiwan
| | - Hwei‐Jan Hsu
- Molecular and Cell BiologyTaiwan International Graduate ProgramAcademia SinicaTaipeiTaiwan
- Graduate Institute of Life ScienceNational Defense Medical CenterTaipeiTaiwan
- Institute of Cellular and Organismic BiologyTaipeiTaiwan
| |
Collapse
|
12
|
Li G, Song Y, Liao Z, Wang K, Luo R, Lu S, Zhao K, Feng X, Liang H, Ma L, Wang B, Ke W, Yin H, Zhan S, Li S, Wu X, Zhang Y, Yang C. Bone-derived mesenchymal stem cells alleviate compression-induced apoptosis of nucleus pulposus cells by N6 methyladenosine of autophagy. Cell Death Dis 2020; 11:103. [PMID: 32029706 DOI: 10.1038/s41419-020-2284-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 12/28/2022]
Abstract
N6 methyladenosine (m6A) is one of the most prevalent epitranscriptomic modifications of mRNAs, and plays a critical role in various bioprocesses. Bone-derived mesenchymal stem cells (BMSCs) can attenuate apoptosis of nucleus pulposus cells (NPCs) under compression; however, the underlying mechanisms are poorly understood. This study showed that the level of m6A mRNA modifications was decreased, and the autophagic flux was increased in NPCs under compression when they were cocultured with BMSCs. We report that under coculture conditions, RNA demethylase ALKBH5-mediated FIP200 mRNA demethylation enhanced autophagic flux and attenuated the apoptosis of NPCs under compression. Specific silencing of ALKBH5 results in impaired autophagic flux and a higher proportion of apoptotic NPCs under compression, even when cocultured with BMSCs. Mechanistically, we further identify that the m6A “reader” YTHDF2 is likely to be involved in the regulation of autophagy, and lower m6A levels in the coding region of FIP200 lead to a reduction in YTHDF2-mediated mRNA degradation of FIP200, a core molecular component of the ULK1 complex that participates in the initiating process of autophagy. Taken together, our study reveals the roles of ALKBH5-mediated FIP200 mRNA demethylation in enhancing autophagy and reducing apoptosis in NPCs when cocultured with BMSCs.
Collapse
|
13
|
Bhattacharjee A, Szabó Á, Csizmadia T, Laczkó-Dobos H, Juhász G. Understanding the importance of autophagy in human diseases using Drosophila. J Genet Genomics 2019; 46:157-169. [PMID: 31080044 DOI: 10.1016/j.jgg.2019.03.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/05/2019] [Accepted: 03/06/2019] [Indexed: 12/19/2022]
Abstract
Autophagy is a lysosome-dependent intracellular degradation pathway that has been implicated in the pathogenesis of various human diseases, either positively or negatively impacting disease outcomes depending on the specific context. The majority of medical conditions including cancer, neurodegenerative diseases, infections and immune system disorders and inflammatory bowel disease could probably benefit from therapeutic modulation of the autophagy machinery. Drosophila represents an excellent model animal to study disease mechanisms thanks to its sophisticated genetic toolkit, and the conservation of human disease genes and autophagic processes. Here, we provide an overview of the various autophagy pathways observed both in flies and human cells (macroautophagy, microautophagy and chaperone-mediated autophagy), and discuss Drosophila models of the above-mentioned diseases where fly research has already helped to understand how defects in autophagy genes and pathways contribute to the relevant pathomechanisms.
Collapse
Affiliation(s)
- Arindam Bhattacharjee
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári Krt. 62., Szeged, H-6726, Hungary
| | - Áron Szabó
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári Krt. 62., Szeged, H-6726, Hungary
| | - Tamás Csizmadia
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Pázmány Sétány 1/C, Budapest, H-1117, Hungary
| | - Hajnalka Laczkó-Dobos
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári Krt. 62., Szeged, H-6726, Hungary
| | - Gábor Juhász
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári Krt. 62., Szeged, H-6726, Hungary; Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Pázmány Sétány 1/C, Budapest, H-1117, Hungary.
| |
Collapse
|
14
|
Nilangekar K, Murmu N, Sahu G, Shravage BV. Generation and Characterization of Germline-Specific Autophagy and Mitochondrial Reactive Oxygen Species Reporters in Drosophila. Front Cell Dev Biol 2019; 7:47. [PMID: 31001531 PMCID: PMC6456670 DOI: 10.3389/fcell.2019.00047] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 03/15/2019] [Indexed: 12/12/2022] Open
Abstract
Oogenesis is a fundamental process that forms the egg and, is crucial for the transmission of genetic information to the next generation. Drosophila oogenesis has been used extensively as a genetically tractable model to study organogenesis, niche-germline stem cell communication, and more recently reproductive aging including germline stem cell (GSC) aging. Autophagy, a lysosome-mediated degradation process, is implicated in gametogenesis and aging. However, there is a lack of genetic tools to study autophagy in the context of gametogenesis and GSC aging. Here we describe the generation of three transgenic lines mcherry-Atg8a, GFP-Ref(2)P and mito-roGFP2-Orp1 that are specifically expressed in the germline compartment including GSCs during Drosophila oogenesis. These transgenes are expressed from the nanos promoter and present a better alternative to UASp mediated overexpression of transgenes. These fluorescent reporters can be used to monitor and quantify autophagy, and the production of reactive oxygen species during oogenesis. These reporters provide a valuable tool that can be utilized in designing genetic screens to identify novel regulators of autophagy and redox homeostasis during oogenesis.
Collapse
Affiliation(s)
- Kiran Nilangekar
- Developmental Biology Group, Agharkar Research Institute, Pune, India.,Department of Biotechnology, Savitribai Phule Pune University (SPPU), Pune, India
| | - Nidhi Murmu
- Developmental Biology Group, Agharkar Research Institute, Pune, India.,Department of Biotechnology, Savitribai Phule Pune University (SPPU), Pune, India
| | - Govind Sahu
- Developmental Biology Group, Agharkar Research Institute, Pune, India
| | - Bhupendra V Shravage
- Developmental Biology Group, Agharkar Research Institute, Pune, India.,Department of Biotechnology, Savitribai Phule Pune University (SPPU), Pune, India
| |
Collapse
|
15
|
Abstract
The resurgence of Drosophila as a recognized model for carcinogenesis has contributed greatly to our conceptual advance and mechanistic understanding of tumor growth in vivo. With its powerful genetics, Drosophila has emerged as a prime model organism to study cell biology and physiological functions of autophagy. This has enabled exploration of the contributions of autophagy in several tumor models. Here we review the literature of autophagy related to tumorigenesis in Drosophila. Functional analysis of core autophagy components does not provide proof for a classical tumor suppression role for autophagy alone. Autophagy both serve to suppress or support tumor growth. These effects are context-specific, depending on cell type and oncogenic or tumor suppressive lesion. Future delineation of how autophagy impinges on tumorigenesis will demand to untangle in detail, the regulation and flux of autophagy in the respective tumor models. The downstream tumor-regulative roles of autophagy through organelle homeostasis, metabolism, selective autophagy or alternative mechanisms remain largely unexplored.
Collapse
Affiliation(s)
- Rojyar Khezri
- Center for Cancer Cell Reprogramming (CanCell), Institute for Clinical Medicine, The Medical Faculty, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Tor Erik Rusten
- Center for Cancer Cell Reprogramming (CanCell), Institute for Clinical Medicine, The Medical Faculty, University of Oslo, Oslo, Norway.
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.
| |
Collapse
|