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Chen J, Li C, Sheng Y, Zhang J, Pang L, Dong Z, Wu Z, Lu Y, Liu Z, Zhang Q, Guan X, Chen X, Huang J. Communication between the stem cell niche and an adjacent differentiation niche through miRNA and EGFR signaling orchestrates exit from the stem cell state in the Drosophila ovary. PLoS Biol 2024; 22:e3002515. [PMID: 38512963 PMCID: PMC10986965 DOI: 10.1371/journal.pbio.3002515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 04/02/2024] [Accepted: 01/22/2024] [Indexed: 03/23/2024] Open
Abstract
The signaling environment, or niche, often governs the initial difference in behavior of an adult stem cell and a derivative that initiates a path towards differentiation. The transition between an instructive stem cell niche and differentiation niche must generally have single-cell resolution, suggesting that multiple mechanisms might be necessary to sharpen the transition. Here, we examined the Drosophila ovary and found that Cap cells, which are key constituents of the germline stem cell (GSC) niche, express a conserved microRNA (miR-124). Surprisingly, loss of miR-124 activity in Cap cells leads to a defect in differentiation of GSC derivatives. We present evidence that the direct functional target of miR-124 in Cap cells is the epidermal growth factor receptor (EGFR) and that failure to limit EGFR expression leads to the ectopic expression of a key anti-differentiation BMP signal in neighboring somatic escort cells (ECs), which constitute a differentiation niche. We further found that Notch signaling connects EFGR activity in Cap cells to BMP expression in ECs. We deduce that the stem cell niche communicates with the differentiation niche through a mechanism that begins with the selective expression of a specific microRNA and culminates in the suppression of the major anti-differentiation signal in neighboring cells, with the functionally important overall role of sharpening the spatial distinction between self-renewal and differentiation environments.
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Affiliation(s)
- Jiani Chen
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Chaosqun Li
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Yifeng Sheng
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Junwei Zhang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Lan Pang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Zhi Dong
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Zhiwei Wu
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Yueqi Lu
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Zhiguo Liu
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Qichao Zhang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Xueying Guan
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Hainan Institute of Zhejiang University, Yazhou Bay Science and Technology City, Sanya, China
| | - Xuexin Chen
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
- Hainan Institute of Zhejiang University, Yazhou Bay Science and Technology City, Sanya, China
| | - Jianhua Huang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
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Smart M, Shvartsman SY, Nunley H. A model of replicating coupled oscillators generates naturally occurring cell networks. Development 2023; 150:dev202187. [PMID: 37823332 PMCID: PMC10690053 DOI: 10.1242/dev.202187] [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: 07/18/2023] [Accepted: 10/02/2023] [Indexed: 10/13/2023]
Abstract
When a founder cell and its progeny divide with incomplete cytokinesis, a network forms in which each intercellular bridge corresponds to a past mitotic event. Such networks are required for gamete production in many animals, and different species have evolved diverse final network topologies. Although mechanisms regulating network assembly have been identified in particular organisms, we lack a quantitative framework to understand network assembly and inter-species variability. Motivated by cell networks responsible for oocyte production in invertebrates, where the final topology is typically invariant within each species, we devised a mathematical model for generating cell networks, in which each node is an oscillator and, after a full cycle, the node produces a daughter to which it remains connected. These cell cycle oscillations are transient and coupled via diffusion over the edges of the network. By variation of three biologically motivated parameters, our model generates nearly all such networks currently reported across invertebrates. Furthermore, small parameter variations can rationalize cases of intra-species variation. Because cell networks outside of the ovary often form less deterministically, we propose model generalizations to account for sources of stochasticity.
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Affiliation(s)
- Matthew Smart
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Stanislav Y. Shvartsman
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08540, USA
| | - Hayden Nunley
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
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3
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Sun Z, Nystul TG, Zhong G. Single-cell RNA sequencing identifies eggplant as a regulator of germ cell development in Drosophila. EMBO Rep 2023; 24:e56475. [PMID: 37603128 PMCID: PMC10561367 DOI: 10.15252/embr.202256475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 07/27/2023] [Accepted: 08/01/2023] [Indexed: 08/22/2023] Open
Abstract
Drosophila ovarian germline stem cells (GSCs) are a powerful model for stem cell research. In this study, we use single-cell RNA sequencing (scRNA-seq), an RNAi screen and bioinformatic analysis, to identify genes involved in germ cell differentiation, including 34 genes with upregulated expression during early germ cell development and 19 genes that may regulate germ cell differentiation. Among these, a gene we have named eggplant (eggpl) is highly expressed in GSCs and downregulated in early daughter cells. RNAi knockdown of eggpl causes germ cell proliferation and differentiation defects. In flies fed a rich yeast diet, the expression of eggpl is significantly lower and knockdown or knockout of eggpl phenocopies a rich diet. In addition, eggpl knockdown suppresses the reduction in germ cell proliferation caused by inhibition of the insulin effector PI3K. These findings suggest that downregulation of eggpl links nutritional status to germ cell proliferation and differentiation. Collectively, this study provides new insights into the signaling networks that regulate early germ cell development and identifies eggpl as a key player in this process.
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Affiliation(s)
- Zhipeng Sun
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhouChina
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of EducationSouth China Agricultural UniversityGuangzhouChina
| | | | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhouChina
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of EducationSouth China Agricultural UniversityGuangzhouChina
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Dong Z, Pang L, Liu Z, Sheng Y, Li X, Thibault X, Reilein A, Kalderon D, Huang J. Single-cell expression profile of Drosophila ovarian follicle stem cells illuminates spatial differentiation in the germarium. BMC Biol 2023; 21:143. [PMID: 37340484 PMCID: PMC10283321 DOI: 10.1186/s12915-023-01636-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 05/26/2023] [Indexed: 06/22/2023] Open
Abstract
BACKGROUND How stem cell populations are organized and regulated within adult tissues is important for understanding cancer origins and for developing cell replacement strategies. Paradigms such as mammalian gut stem cells and Drosophila ovarian follicle stem cells (FSC) are characterized by population asymmetry, in which stem cell division and differentiation are separately regulated processes. These stem cells behave stochastically regarding their contributions to derivative cells and also exhibit dynamic spatial heterogeneity. Drosophila FSCs provide an excellent model for understanding how a community of active stem cells maintained by population asymmetry is regulated. Here, we use single-cell RNA sequencing to profile the gene expression patterns of FSCs and their immediate derivatives to investigate heterogeneity within the stem cell population and changes associated with differentiation. RESULTS We describe single-cell RNA sequencing studies of a pre-sorted population of cells that include FSCs and the neighboring cell types, escort cells (ECs) and follicle cells (FCs), which they support. Cell-type assignment relies on anterior-posterior (AP) location within the germarium. We clarify the previously determined location of FSCs and use spatially targeted lineage studies as further confirmation. The scRNA profiles among four clusters are consistent with an AP progression from anterior ECs through posterior ECs and then FSCs, to early FCs. The relative proportion of EC and FSC clusters are in good agreement with the prevalence of those cell types in a germarium. Several genes with graded profiles from ECs to FCs are highlighted as candidate effectors of the inverse gradients of the two principal signaling pathways, Wnt and JAK-STAT, that guide FSC differentiation and division. CONCLUSIONS Our data establishes an important resource of scRNA-seq profiles for FSCs and their immediate derivatives that is based on precise spatial location and functionally established stem cell identity, and facilitates future genetic investigation of regulatory interactions guiding FSC behavior.
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Affiliation(s)
- Zhi Dong
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Lan Pang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Zhiguo Liu
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yifeng Sheng
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Xiaoping Li
- Department of Hepatic Surgery and Liver Transplantation Center of the Third Affiliated Hospital, Organ Transplantation Institute, Sun Yat-Sen University, Guangzhou, 510630, Guangdong, China
| | - Xavier Thibault
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Amy Reilein
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Daniel Kalderon
- Department of Biological Sciences, Columbia University, New York, NY, USA.
| | - Jianhua Huang
- Institute of Insect Sciences, Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
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5
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Galasso A, Xu DC, Hill C, Iakovleva D, Stefana MI, Baena‐Lopez LA. Non-apoptotic caspase activation ensures the homeostasis of ovarian somatic stem cells. EMBO Rep 2023; 24:e51716. [PMID: 37039000 PMCID: PMC10240206 DOI: 10.15252/embr.202051716] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/22/2023] [Accepted: 03/14/2023] [Indexed: 04/12/2023] Open
Abstract
Current evidence has associated caspase activation with the regulation of basic cellular functions without causing apoptosis. Malfunction of non-apoptotic caspase activities may contribute to specific neurological disorders, metabolic diseases, autoimmune conditions and cancers. However, our understanding of non-apoptotic caspase functions remains limited. Here, we show that non-apoptotic caspase activation prevents the intracellular accumulation of the Patched receptor in autophagosomes and the subsequent Patched-dependent induction of autophagy in Drosophila follicular stem cells. These events ultimately sustain Hedgehog signalling and the physiological properties of ovarian somatic stem cells and their progeny under moderate thermal stress. Importantly, our key findings are partially conserved in ovarian somatic cells of human origin. These observations attribute to caspases a pro-survival role under certain cellular conditions.
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Affiliation(s)
- Alessia Galasso
- Faculty of Medicine CentreImperial College London, South Kensington CampusLondonUK
| | - Derek Cui Xu
- Sir William Dunn School of PathologyUniversity of OxfordOxfordUK
| | - Claire Hill
- School of Medicine, Dentistry and Biomedical SciencesQueen's University Belfast MedicineBelfastUK
| | - Daria Iakovleva
- Center for Regenerative MedicineUniversity of EdinburghEdinburghUK
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Chatterjee D, Cong F, Wang XF, Machado Costa CA, Huang YC, Deng WM. Cell polarity opposes Jak/STAT-mediated Escargot activation that drives intratumor heterogeneity in a Drosophila tumor model. Cell Rep 2023; 42:112061. [PMID: 36709425 PMCID: PMC10374876 DOI: 10.1016/j.celrep.2023.112061] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 11/28/2022] [Accepted: 01/18/2023] [Indexed: 01/30/2023] Open
Abstract
In proliferating neoplasms, microenvironment-derived selective pressures promote tumor heterogeneity by imparting diverse capacities for growth, differentiation, and invasion. However, what makes a tumor cell respond to signaling cues differently from a normal cell is not well understood. In the Drosophila ovarian follicle cells, apicobasal-polarity loss induces heterogeneous epithelial multilayering. When exacerbated by oncogenic-Notch expression, this multilayer displays an increased consistency in the occurrence of morphologically distinguishable cells adjacent to the polar follicle cells. Polar cells release the Jak/STAT ligand Unpaired (Upd), in response to which neighboring polarity-deficient cells exhibit a precursor-like transcriptomic state. Among the several regulons active in these cells, we could detect and further validate the expression of Snail family transcription factor Escargot (Esg). We also ascertain a similar relationship between Upd and Esg in normally developing ovaries, where establishment of polarity determines early follicular differentiation. Overall, our results indicate that epithelial-cell polarity acts as a gatekeeper against microenvironmental selective pressures that drive heterogeneity.
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Affiliation(s)
- Deeptiman Chatterjee
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA
| | - Fei Cong
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA
| | - Xian-Feng Wang
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA
| | - Caique Almeida Machado Costa
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA
| | - Yi-Chun Huang
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA
| | - Wu-Min Deng
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA 70112, USA.
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7
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Gao J, Gao Y, Xiao G. The expression of Catsup in escort cells affects Drosophila ovarian stem cell niche establishment and germline stem cells self-renewal via Notch signaling. Biochem Biophys Res Commun 2023; 641:1-9. [PMID: 36516479 DOI: 10.1016/j.bbrc.2022.11.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 11/30/2022] [Indexed: 12/07/2022]
Abstract
Stem cell niche provides extrinsic signals to maintain stem cell renewal or initiate cell differentiation. Drosophila niche is composed of somatic terminal filament cells, cap cells and escort cells. However, the underlying mechanism for the development of stem cell niche remains largely unclear. Here we found that the expression of a zinc transporter Catsup is essential for ovary morphogenesis. Catsup knockdown in escort cells results in defects of niche establishment and germline stem cells self-renewal. These defects could be modified by altered expression of genes involved in zinc metabolism or intervention of dietary zinc levels. Further studies indicated that Catsup RNAi affected adult ovary morphogenesis by suppressing Notch signaling. Lastly, we demonstrated that the defects of Catsup RNAi could be restored by overexpression of heat shock cognate protein 70 (Hsc70). These findings expand our understanding of the mechanisms controlling adult oogenesis and niche establishment in Drosophila.
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Affiliation(s)
- Jiajia Gao
- China Light Industry Key Laboratory of Meat Microbial Control and Utilization, Hefei University of Technology, Hefei, 230009, China; Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Yan Gao
- China Light Industry Key Laboratory of Meat Microbial Control and Utilization, Hefei University of Technology, Hefei, 230009, China; Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Guiran Xiao
- China Light Industry Key Laboratory of Meat Microbial Control and Utilization, Hefei University of Technology, Hefei, 230009, China; Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China.
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8
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Zhang J, Zhang S, Sun Z, Cai Y, Zhong G, Yi X. Camptothecin Effectively Regulates Germline Differentiation through Bam-Cyclin A Axis in Drosophila melanogaster. Int J Mol Sci 2023; 24:ijms24021617. [PMID: 36675143 PMCID: PMC9864452 DOI: 10.3390/ijms24021617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
Camptothecin (CPT), first isolated from Chinese tree Camptotheca acuminate, produces rapid and prolonged inhibition of DNA synthesis and induction of DNA damage by targeting topoisomerase I (top1), which is highly activated in cancer cells. CPT thus exhibits remarkable anticancer activities in various cancer types, and is a promising therapeutic agent for the treatment of cancers. However, it remains to be uncovered underlying its cytotoxicity toward germ cells. In this study we found that CPT, a cell cycle-specific anticancer agent, reduced fecundity and exhibited significant cytotoxicity toward GSCs and two-cell cysts. We showed that CPT induced GSC loss and retarded two-cell cysts differentiation in a niche- or apoptosis-independent manner. Instead, CPT induced ectopic expression of a differentiation factor, bag of marbles (Bam), and regulated the expression of cyclin A, which contributed to GSC loss. In addition, CPT compromised two-cell cysts differentiation by decreasing the expression of Bam and inducing cell arrest at G1/S phase via cyclin A, eventually resulting in two-cell accumulation. Collectively, this study demonstrates, for the first time in vivo, that the Bam-cyclin A axis is involved in CPT-mediated germline stem cell loss and two-cell cysts differentiation defects via inducing cell cycle arrest, which could provide information underlying toxicological effects of CPT in the productive system, and feature its potential to develop as a pharmacology-based germline stem cell regulation agent.
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Affiliation(s)
- Jing Zhang
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Shijie Zhang
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Zhipeng Sun
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Yu Cai
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 119077, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore 119077, Singapore
| | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (G.Z.); (X.Y.)
| | - Xin Yi
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Correspondence: (G.Z.); (X.Y.)
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Chatterjee D, Deng WM. Standardization of Single-Cell RNA-Sequencing Analysis Workflow to Study Drosophila Ovary. Methods Mol Biol 2023; 2677:151-171. [PMID: 37464241 DOI: 10.1007/978-1-0716-3259-8_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Developments in single-cell technology have considerably changed the way we study biology. Significant efforts have been made over the last few years to build comprehensive cell-type-specific transcriptomic atlases for a wide range of tissues in several model organisms in order to discover cell-type-specific markers and drivers of gene expression. One such tissue is the ovary of the fruit-fly Drosophila melanogaster, which is a popular model system with wide-ranging applications in the study of both development and disease. Three independent studies have recently produced comprehensive maps of cell-type-specific gene expression that describe both spatiotemporal regulation of the process of oogenesis and unique transcriptomic profiles of different cell types that constitute the ovary. In this chapter, we outlined the wet-lab protocol that was followed in our recent study for sample preparation and reanalyze the resultant dataset to discuss the benchmarks in data analysis, which are fundamental to comprehensive curation of the single-cell dataset representing the fly ovary.
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Affiliation(s)
- Deeptiman Chatterjee
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA, USA.
- Current address: Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
| | - Wu-Min Deng
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA, USA.
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10
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Siddall NA, Casagranda F, Johanson TM, Dominado N, Heaney J, Sutherland JM, McLaughlin EA, Hime GR. MiMIC analysis reveals an isoform specific role for Drosophila Musashi in follicle stem cell maintenance and escort cell function. Cell Death Dis 2022; 8:455. [DOI: 10.1038/s41420-022-01245-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 10/30/2022] [Accepted: 10/31/2022] [Indexed: 11/13/2022]
Abstract
AbstractThe Drosophila ovary is regenerated from germline and somatic stem cell populations that have provided fundamental conceptual understanding on how adult stem cells are regulated within their niches. Recent ovarian transcriptomic studies have failed to identify mRNAs that are specific to follicle stem cells (FSCs), suggesting that their fate may be regulated post-transcriptionally. We have identified that the RNA-binding protein, Musashi (Msi) is required for maintaining the stem cell state of FSCs. Loss of msi function results in stem cell loss, due to a change in differentiation state, indicated by upregulation of Lamin C in the stem cell population. In msi mutant ovaries, Lamin C upregulation was also observed in posterior escort cells that interact with newly formed germ cell cysts. Mutant somatic cells within this region were dysfunctional, as evidenced by the presence of germline cyst collisions, fused egg chambers and an increase in germ cell cyst apoptosis. The msi locus produces two classes of mRNAs (long and short). We show that FSC maintenance and escort cell function specifically requires the long transcripts, thus providing the first evidence of isoform-specific regulation in a population of Drosophila epithelial cells. We further demonstrate that although male germline stem cells have previously been shown to require Msi function to prevent differentiation this is not the case for female germline stem cells, indicating that these similar stem cell types have different requirements for Msi, in addition to the differential use of Msi isoforms between soma and germline. In summary, we show that different isoforms of the Msi RNA-binding protein are expressed in specific cell populations of the ovarian stem cell niche where Msi regulates stem cell differentiation, niche cell function and subsequent germ cell survival and differentiation.
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11
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Laws KM, Bashaw GJ. Diverse roles for axon guidance pathways in adult tissue architecture and function. NATURAL SCIENCES (WEINHEIM, GERMANY) 2022; 2:e20220021. [PMID: 37456985 PMCID: PMC10346896 DOI: 10.1002/ntls.20220021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Classical axon guidance ligands and their neuronal receptors were first identified due to their fundamental roles in regulating connectivity in the developing nervous system. Since their initial discovery, it has become clear that these signaling molecules play important roles in the development of a broad array of tissue and organ systems across phylogeny. In addition to these diverse developmental roles, there is a growing appreciation that guidance signaling pathways have important functions in adult organisms, including the regulation of tissue integrity and homeostasis. These roles in adult organisms include both tissue-intrinsic activities of guidance molecules, as well as systemic effects on tissue maintenance and function mediated by the nervous and vascular systems. While many of these adult functions depend on mechanisms that mirror developmental activities, such as regulating adhesion and cell motility, there are also examples of adult roles that may reflect signaling activities that are distinct from known developmental mechanisms, including the contributions of guidance signaling pathways to lineage commitment in the intestinal epithelium and bone remodeling in vertebrates. In this review, we highlight studies of guidance receptors and their ligands in adult tissues outside of the nervous system, focusing on in vivo experimental contexts. Together, these studies lay the groundwork for future investigation into the conserved and tissue-specific mechanisms of guidance receptor signaling in adult tissues.
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Affiliation(s)
- Kaitlin M. Laws
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Current address: Department of Biology, Randolph-Macon College, Ashland, VA 23005, USA
| | - Greg J. Bashaw
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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12
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Diegmiller R, Nunley H, Shvartsman SY, Imran Alsous J. Quantitative models for building and growing fated small cell networks. Interface Focus 2022; 12:20210082. [PMID: 35865502 PMCID: PMC9184967 DOI: 10.1098/rsfs.2021.0082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 03/31/2022] [Indexed: 02/07/2023] Open
Abstract
Small cell clusters exhibit numerous phenomena typically associated with complex systems, such as division of labour and programmed cell death. A conserved class of such clusters occurs during oogenesis in the form of germline cysts that give rise to oocytes. Germline cysts form through cell divisions with incomplete cytokinesis, leaving cells intimately connected through intercellular bridges that facilitate cyst generation, cell fate determination and collective growth dynamics. Using the well-characterized Drosophila melanogaster female germline cyst as a foundation, we present mathematical models rooted in the dynamics of cell cycle proteins and their interactions to explain the generation of germline cell lineage trees (CLTs) and highlight the diversity of observed CLT sizes and topologies across species. We analyse competing models of symmetry breaking in CLTs to rationalize the observed dynamics and robustness of oocyte fate specification, and highlight remaining gaps in knowledge. We also explore how CLT topology affects cell cycle dynamics and synchronization and highlight mechanisms of intercellular coupling that underlie the observed collective growth patterns during oogenesis. Throughout, we point to similarities across organisms that warrant further investigation and comment on the extent to which experimental and theoretical findings made in model systems extend to other species.
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Affiliation(s)
- Rocky Diegmiller
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Hayden Nunley
- Flatiron Institute, Simons Foundation, New York, NY, USA
| | - Stanislav Y. Shvartsman
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA,Department of Molecular Biology, Princeton University, Princeton, NJ, USA,Flatiron Institute, Simons Foundation, New York, NY, USA
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13
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Cyst stem cell lineage eIF5 non-autonomously prevents testicular germ cell tumor formation via eIF1A/eIF2γ-mediated pre-initiation complex. Stem Cell Res Ther 2022; 13:351. [PMID: 35883200 PMCID: PMC9327282 DOI: 10.1186/s13287-022-03025-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 07/02/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Stem cell niche maintains stem cell population identity and is essential for the homeostasis of self-renewal and differentiation in Drosophila testes. However, the mechanisms of CySC lineage signals-mediated soma-germline communications in response to external stimuli are unclear. METHODS Pre-initiation complex functions were evaluated by UAS-Gal4-mediated cell effects. RNA sequencing was conducted in NC and eIF5 siRNA-treated cells. Genetic interaction analysis was used to indicate the relationships between eIF5 and eIF1A/eIF2γ in Drosophila testes. RESULTS Here, we demonstrated that in CySCs, translation initiation factor eIF5 mediates cyst cell differentiation and the non-autonomously affected germ cell differentiation process. CySCs lacking eIF5 displayed unbalanced cell proliferation and apoptosis, forming testicular germ cell tumors (TGCTs) during spermatogenesis. eIF5 transcriptional regulation network analysis identified multiple metabolic processes and several key factors that might be involved in germ cell differentiation and TGCT formation. Importantly, knockdown of eIF1A and eIF2γ, key components of pre-initiation complex, mimicked the phenotype of knocking down eIF5 in the stem cell niche of Drosophila testes. Genetic interaction analysis indicated that eIF5 was sufficient to rescue the phenotype of tumorlike structures induced by down-regulating eIF1A or eIF2γ in CySCs. CONCLUSIONS These findings demonstrated that CySC lineage eIF5, together with eIF1A or eIF2γ, mediates soma-germline communications for the stem cell niche homeostasis in Drosophila testes, providing new insights for the prevention of TGCTs.
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Szarka-Kovács AB, Takács Z, Bence M, Erdélyi M, Jankovics F. Drosophila MESR4 Gene Ensures Germline Stem Cell Differentiation by Promoting the Transcription of bag of marbles. Cells 2022; 11:cells11132056. [PMID: 35805140 PMCID: PMC9265997 DOI: 10.3390/cells11132056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 12/02/2022] Open
Abstract
Ovarian germline stem cells (GSCs) of Drosophila melanogaster provide a valuable in vivo model to investigate how the adult stem cell identity is maintained and the differentiation of the daughter cells is regulated. GSCs are embedded into a specialized cellular microenvironment, the so-called stem cell niche. Besides the complex signaling interactions between the germ cells and the niche cells, the germ cell intrinsic mechanisms, such as chromatin regulation and transcriptional control, are also crucial in the decision about self-renewal and differentiation. The key differentiation regulator gene is the bag of marbles (bam), which is transcriptionally repressed in the GSCs and de-repressed in the differentiating daughter cell. Here, we show that the transcription factor MESR4 functions in the germline to promote GSC daughter differentiation. We find that the loss of MESR4 results in the accumulation of GSC daughter cells which fail to transit from the pre-cystoblast (pre-CB) to the differentiated cystoblast (CB) stage. The forced expression of bam can rescue this differentiation defect. By a series of epistasis experiments and a transcriptional analysis, we demonstrate that MESR4 positively regulates the transcription of bam. Our results suggest that lack of repression alone is not sufficient, but MESR4-mediated transcriptional activation is also required for bam expression.
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Affiliation(s)
- Alexandra Brigitta Szarka-Kovács
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, H-6726 Szeged, Hungary; (A.B.S.-K.); (Z.T.); (M.B.)
- Doctoral School in Biology, University of Szeged, H-6720 Szeged, Hungary
| | - Zsanett Takács
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, H-6726 Szeged, Hungary; (A.B.S.-K.); (Z.T.); (M.B.)
| | - Melinda Bence
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, H-6726 Szeged, Hungary; (A.B.S.-K.); (Z.T.); (M.B.)
| | - Miklós Erdélyi
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, H-6726 Szeged, Hungary; (A.B.S.-K.); (Z.T.); (M.B.)
- Correspondence: (M.E.); (F.J.)
| | - Ferenc Jankovics
- Institute of Genetics, Biological Research Centre, Eötvös Loránd Research Network, H-6726 Szeged, Hungary; (A.B.S.-K.); (Z.T.); (M.B.)
- Department of Medical Biology, Albert Szent-Györgyi Medical School, University of Szeged, H-6720 Szeged, Hungary
- Correspondence: (M.E.); (F.J.)
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15
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Deng M, Wang Y, Yan Y. Mining cell–cell signaling in single-cell transcriptomics atlases. Curr Opin Cell Biol 2022; 76:102101. [DOI: 10.1016/j.ceb.2022.102101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 03/16/2022] [Accepted: 04/24/2022] [Indexed: 12/22/2022]
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16
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Martin ET, Sarkar K, McCarthy A, Rangan P. Oo-site: A dashboard to visualize gene expression during Drosophila oogenesis suggests meiotic entry is regulated post-transcriptionally. Biol Open 2022; 11:275394. [PMID: 35579517 PMCID: PMC9148541 DOI: 10.1242/bio.059286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/19/2022] [Indexed: 11/20/2022] Open
Abstract
Determining how stem cell differentiation is controlled has important implications for understanding the etiology of degenerative disease and designing regenerative therapies. In vivo analyses of stem cell model systems have revealed regulatory paradigms for stem cell self-renewal and differentiation. The germarium of the female Drosophila gonad, which houses both germline and somatic stem cells, is one such model system. Bulk mRNA sequencing (RNA-seq), single-cell RNA-seq (scRNA-seq), and bulk translation efficiency (polysome-seq) of mRNAs are available for stem cells and their differentiating progeny within the Drosophila germarium. However, visualizing those data is hampered by the lack of a tool to spatially map gene expression and translational data in the germarium. Here, we have developed Oo-site (https://www.ranganlab.com/Oo-site), a tool for visualizing bulk RNA-seq, scRNA-seq, and translational efficiency data during different stages of germline differentiation, which makes these data accessible to non-bioinformaticians. Using this tool, we recapitulated previously reported expression patterns of developmentally regulated genes and discovered that meiotic genes, such as those that regulate the synaptonemal complex, are regulated at the level of translation.
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Affiliation(s)
- Elliot T Martin
- Department of Biological Sciences/RNA Institute, University at Albany SUNY, Albany, NY 12202, USA
| | - Kahini Sarkar
- Department of Biological Sciences/RNA Institute, University at Albany SUNY, Albany, NY 12202, USA.,Black Family Stem Cell Institute, Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Alicia McCarthy
- Department of Biological Sciences/RNA Institute, University at Albany SUNY, Albany, NY 12202, USA
| | - Prashanth Rangan
- Department of Biological Sciences/RNA Institute, University at Albany SUNY, Albany, NY 12202, USA.,Black Family Stem Cell Institute, Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
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17
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Khan UW, Newmark PA. Somatic regulation of female germ cell regeneration and development in planarians. Cell Rep 2022; 38:110525. [PMID: 35294875 PMCID: PMC8994625 DOI: 10.1016/j.celrep.2022.110525] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/11/2022] [Accepted: 02/22/2022] [Indexed: 12/23/2022] Open
Abstract
Female germ cells develop into oocytes, with the capacity for totipotency. In most animals, these remarkable cells are specified during development and cannot be regenerated. By contrast, planarians, known for their regenerative prowess, can regenerate germ cells. To uncover mechanisms required for female germ cell development and regeneration, we generated gonad-specific transcriptomes and identified genes whose expression defines progressive stages of female germ cell development. Strikingly, early female germ cells share molecular signatures with the pluripotent stem cells driving planarian regeneration. We observe spatial heterogeneity within somatic ovarian cells and find that a regionally enriched foxL homolog is required for oocyte differentiation, but not specification, suggestive of functionally distinct somatic compartments. Unexpectedly, a neurotransmitter-biosynthetic enzyme, aromatic L-amino acid decarboxylase (AADC), is also expressed in somatic gonadal cells, and plays opposing roles in female and male germ cell development. Thus, somatic gonadal cells deploy conserved factors to regulate germ cell development and regeneration in planarians. Unlike most animals, planarians can regenerate germ cells. Here, Khan and Newmark characterize gene expression in the planarian ovary, identifying genes expressed at progressive stages of female germ cell development and in somatic ovarian cells. Functional characterization revealed somatically expressed genes required for specification or differentiation of female germ cells.
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Affiliation(s)
- Umair W Khan
- Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI, USA; Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, USA
| | - Phillip A Newmark
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, USA; Howard Hughes Medical Institute, Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI, USA.
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18
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Reilein A, Kogan HV, Misner R, Park KS, Kalderon D. Adult stem cells and niche cells segregate gradually from common precursors that build the adult Drosophila ovary during pupal development. eLife 2021; 10:69749. [PMID: 34590579 PMCID: PMC8536258 DOI: 10.7554/elife.69749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 09/29/2021] [Indexed: 12/31/2022] Open
Abstract
Production of proliferative follicle cells (FCs) and quiescent escort cells (ECs) by follicle stem cells (FSCs) in adult Drosophila ovaries is regulated by niche signals from anterior (cap cells, ECs) and posterior (polar FCs) sources. Here we show that ECs, FSCs, and FCs develop from common pupal precursors, with different fates acquired by progressive separation of cells along the AP axis and a graded decline in anterior cell proliferation. ECs, FSCs, and most FCs derive from intermingled cell (IC) precursors interspersed with germline cells. Precursors also accumulate posterior to ICs before engulfing a naked germline cyst projected out of the germarium to form the first egg chamber and posterior polar FC signaling center. Thus, stem and niche cells develop in appropriate numbers and spatial organization through regulated proliferative expansion together with progressive establishment of spatial signaling cues that guide adult cell behavior, rather than through rigid early specification events.
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Affiliation(s)
- Amy Reilein
- Department of Biological Sciences, Columbia University, New York, United States
| | - Helen V Kogan
- Department of Biological Sciences, Columbia University, New York, United States
| | - Rachel Misner
- Department of Biological Sciences, Columbia University, New York, United States
| | - Karen Sophia Park
- Department of Biological Sciences, Columbia University, New York, United States
| | - Daniel Kalderon
- Department of Biological Sciences, Columbia University, New York, United States
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Slaidina M, Gupta S, Banisch TU, Lehmann R. A single-cell atlas reveals unanticipated cell type complexity in Drosophila ovaries. Genome Res 2021; 31:1938-1951. [PMID: 34389661 DOI: 10.1101/gr.274340.120] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 08/09/2021] [Indexed: 11/24/2022]
Abstract
Organ function relies on the spatial organization and functional coordination of numerous cell types. The Drosophila ovary is a widely used model system to study the cellular activities underlying organ function, including stem cell regulation, cell signaling and epithelial morphogenesis. However, the relative paucity of cell type-specific reagents hinders investigation of molecular functions at the appropriate cellular resolution. Here, we used single-cell RNA sequencing to characterize all cell types of the stem cell compartment and early follicles of the Drosophila ovary. We computed transcriptional signatures and identified specific markers for nine states of germ cell differentiation, and 23 somatic cell types and subtypes. We uncovered an unanticipated diversity of escort cells, the somatic cells that directly interact with differentiating germline cysts. Three escort cell subtypes reside in discrete anatomical positions, and express distinct sets of secreted and transmembrane proteins, suggesting that diverse micro-environments support the progressive differentiation of germ cells. Finally, we identified 17 follicle cell subtypes, and characterized their transcriptional profiles. Altogether, we provide a comprehensive resource of gene expression, cell type-specific markers, spatial coordinates and functional predictions for 34 ovarian cell types and subtypes.
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Affiliation(s)
| | - Selena Gupta
- Skirball Institute, NYU Grossman School of Medicine
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