1
|
Zhang Q, Li L, Zhang Q, Zhang Y, Yan L, Wang Y, Wang Y, Zhao S. Genetic circuitry controlling Drosophila female germline overgrowth. Dev Biol 2024; 515:160-168. [PMID: 39067502 DOI: 10.1016/j.ydbio.2024.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 07/22/2024] [Accepted: 07/24/2024] [Indexed: 07/30/2024]
Abstract
Germ cells mutant for bam or bgcn are locked in a germline stem cell (GSC)-like state, leading to tumor-like overgrowth in Drosophila ovaries. Our previous studies have demonstrated that germline overgrowth in bam mutants can be suppressed by defects in the miRNA pathway but enhanced by a null mutation in hippo. However, the genetic epistasis between the miRNA and Hippo pathways still remains unknown. Here, we determined that the miRNA pathway acts downstream of the Hippo pathway in regulating this process. Germ cells mutant for bam or bgcn and defective in both pathways divide very slowly, phenocopying those defective only in the miRNA pathway. In addition, we found that Yki, a key oncoprotein in the Hippo pathway, promotes the growth of both wild-type germ cells and bam mutant GSC-like cells. Like wild-type GSCs, bam mutant GSC-like cells predominantly stay in the G2 phase. Remarkably, many of those defective in the miRNA pathway are arrested before entering this phase. Furthermore, our studies identified bantam as a critical miRNA promoting germline overgrowth in bam or bgcn mutants. Taken together, these findings establish a genetic circuitry controlling Drosophila female germline overgrowth.
Collapse
Affiliation(s)
- Qian Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Le Li
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Qi Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Yang Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Lizhong Yan
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Yanfang Wang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Yuejia Wang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
| | - Shaowei Zhao
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China.
| |
Collapse
|
2
|
Pek JW. The idiosyncrasies of oocytes. Trends Cell Biol 2024:S0962-8924(24)00144-2. [PMID: 39142921 DOI: 10.1016/j.tcb.2024.07.006] [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: 05/09/2024] [Revised: 07/17/2024] [Accepted: 07/18/2024] [Indexed: 08/16/2024]
Abstract
Animal oocytes face extreme challenges. They remain dormant in the body for long periods of time. To support offspring development and health, they need to store genetic material and maternal factors stably and at the same time manage cellular damage in a reliable manner. Recent studies have provided new insights on how oocytes cope with such challenges. This review discusses the many unusual or idiosyncratic nature of oocytes and how understanding oocyte biology can help us address issues of reproduction and intergenerational inheritance.
Collapse
Affiliation(s)
- Jun Wei Pek
- Temasek Life Sciences Laboratory, 1 Research Link National University of Singapore, Singapore 117604, Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive, 117543, Singapore.
| |
Collapse
|
3
|
Zhang Q, Wang Y, Bu Z, Zhang Y, Zhang Q, Li L, Yan L, Wang Y, Zhao S. Ras promotes germline stem cell division in Drosophila ovaries. Stem Cell Reports 2024; 19:1205-1216. [PMID: 39029459 DOI: 10.1016/j.stemcr.2024.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 06/17/2024] [Accepted: 06/18/2024] [Indexed: 07/21/2024] Open
Abstract
The Ras family genes are proto-oncogenes that are highly conserved from Drosophila to humans. In Drosophila, RasV12 is a constitutively activated form of the Ras oncoprotein, and its function in cell-cycle progression is context dependent. However, how it influences the cell cycle of female germline stem cells (GSCs) still remains unknown. Using both wild-type GSCs and bam mutant GSC-like cells as model systems, here we determined that RasV12 overexpression promotes GSC division, not growth, opposite to that in somatic wing disc cells. Ras performs this function through activating the mitogen-activated protein kinase (MAPK) signaling. This signaling is activated specifically in the M phase of mitotic germ cells, including both wild-type GSCs and bam mutant GSC-like cells. Furthermore, RasV12 overexpression triggers polyploid nurse cells to die through inducing mitotic stress. Given the similarities between Drosophila and mammalian GSCs, we propose that the Ras/MAPK signaling also promotes mammalian GSC division.
Collapse
Affiliation(s)
- Qi Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Yanfang Wang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Zhenan Bu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Yang Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Qian Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Le Li
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Lizhong Yan
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Yuejia Wang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China
| | - Shaowei Zhao
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, People's Republic of China.
| |
Collapse
|
4
|
Nashchekin D, Squires I, Prokop A, St Johnston D. The Shot CH1 domain recognises a distinct form of F-actin during Drosophila oocyte determination. Development 2024; 151:dev202370. [PMID: 38564309 PMCID: PMC11058685 DOI: 10.1242/dev.202370] [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: 09/21/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024]
Abstract
In Drosophila, only one cell in a multicellular female germline cyst is specified as an oocyte and a similar process occurs in mammals. The symmetry-breaking cue for oocyte selection is provided by the fusome, a tubular structure connecting all cells in the cyst. The Drosophila spectraplakin Shot localises to the fusome and translates its asymmetry into a polarised microtubule network that is essential for oocyte specification, but how Shot recognises the fusome is unclear. Here, we demonstrate that the actin-binding domain (ABD) of Shot is necessary and sufficient to localise Shot to the fusome and mediates Shot function in oocyte specification together with the microtubule-binding domains. The calponin homology domain 1 of the Shot ABD recognises fusomal F-actin and requires calponin homology domain 2 to distinguish it from other forms of F-actin in the cyst. By contrast, the ABDs of utrophin, Fimbrin, Filamin, Lifeact and F-tractin do not recognise fusomal F-actin. We therefore propose that Shot propagates fusome asymmetry by recognising a specific conformational state of F-actin on the fusome.
Collapse
Affiliation(s)
- Dmitry Nashchekin
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Iolo Squires
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Andreas Prokop
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biology, Manchester M13 9PT, UK
| | - Daniel St Johnston
- The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| |
Collapse
|
5
|
Wang ZH, Zhao W, Combs CA, Zhang F, Knutson JR, Lilly MA, Xu H. Mechanical stimulation from the surrounding tissue activates mitochondrial energy metabolism in Drosophila differentiating germ cells. Dev Cell 2023; 58:2249-2260.e9. [PMID: 37647895 PMCID: PMC10843713 DOI: 10.1016/j.devcel.2023.08.007] [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: 03/06/2023] [Revised: 06/24/2023] [Accepted: 08/04/2023] [Indexed: 09/01/2023]
Abstract
In multicellular lives, the differentiation of stem cells and progenitor cells is often accompanied by a transition from glycolysis to mitochondrial oxidative phosphorylation (OXPHOS). However, the underlying mechanism of this metabolic transition remains largely unknown. In this study, we investigate the role of mechanical stress in activating OXPHOS during differentiation of the female germline cyst in Drosophila. We demonstrate that the surrounding somatic cells flatten the 16-cell differentiating cyst, resulting in an increase of the membrane tension of germ cells inside the cyst. This mechanical stress is necessary to maintain cytosolic Ca2+ concentration in germ cells through a mechanically activated channel, transmembrane channel-like. The sustained cytosolic Ca2+ triggers a CaMKI-Fray-JNK signaling relay, leading to the transcriptional activation of OXPHOS in differentiating cysts. Our findings demonstrate a molecular link between cell mechanics and mitochondrial energy metabolism, with implications for other developmentally orchestrated metabolic transitions in mammals.
Collapse
Affiliation(s)
- Zong-Heng Wang
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wenjing Zhao
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Christian A Combs
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Fan Zhang
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jay R Knutson
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mary A Lilly
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hong Xu
- National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
6
|
Diak N, Śliwińska MA, Student S, Świątek P. The three-dimensional conformation and activity of mitochondria in syncytial male germ line-cysts of medicinal leeches. Cell Tissue Res 2023; 394:325-342. [PMID: 37642734 PMCID: PMC10638204 DOI: 10.1007/s00441-023-03825-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 08/15/2023] [Indexed: 08/31/2023]
Abstract
We studied the spatial conformation and activity of mitochondria in the developing syncytial male germline cysts during spermatogenesis of the medicinal leeches using light, fluorescent, transmission electron microscopy, and serial block-face scanning electron microscopy. In cysts with spermatogonia and spermatocytes, mitochondria form networks and are in a dynamic hyperfusion state, while in cysts with spermatids, a single huge mitochondrion is observed. As spermiogenesis progresses, this huge mitochondrion is finally located in the future midpiece. The highest activity, in terms of membrane potential, of the mitochondria in H. medicinalis germline cysts was observed in cysts with spermatocytes; the lowest was in cysts with late elongated spermatids.
Collapse
Affiliation(s)
- Natalia Diak
- University of Silesia in Katowice, Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, Bankowa 9, 40-007, Katowice, Poland.
- Department of Medical Genetics, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland.
| | - Małgorzata Alicja Śliwińska
- Laboratory of Imaging Tissue Structure and Function, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Ludwika Pasteura 3, 02-093, Warsaw, Poland
| | - Sebastian Student
- Silesian University of Technology, Faculty of Automatic Control, Electronics and Computer Science, Akademicka 16, 44-100, Gliwice, Poland
- Silesian University of Technology, Biotechnology Center, Krzywoustego 8, 44-100, Gliwice, Poland
| | - Piotr Świątek
- University of Silesia in Katowice, Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, Bankowa 9, 40-007, Katowice, Poland
| |
Collapse
|
7
|
Mizuta K, Saitou M. Key mechanisms and in vitro reconstitution of fetal oocyte development in mammals. Curr Opin Genet Dev 2023; 82:102091. [PMID: 37556984 DOI: 10.1016/j.gde.2023.102091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/23/2023] [Accepted: 07/01/2023] [Indexed: 08/11/2023]
Abstract
During fetal oocyte development in mammals, germ cells progress through meiotic prophase I to form primordial follicles with pregranulosa cells. The primordial follicles remain dormant until oogenesis resumes during puberty. Studies in mice have elucidated mechanisms governing oogenesis, leading to the successful induction of functional oocytes from mouse pluripotent stem cells in vitro. Based on the in vivo/in vitro knowledge in mice and the histological and transcriptomic evidence for fetal oocyte development in humans and primates, human/primate oocyte-like cells corresponding to the early stage of oocytes in vivo have been successfully induced in vitro. Here, we discuss recent advances in our understanding of the mechanisms of fetal oocyte development in mammals, as well as in in vitro oogenesis.
Collapse
Affiliation(s)
- Ken Mizuta
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Mitinori Saitou
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| |
Collapse
|
8
|
Piazza YG, Czuchlej SC, Gómez ML, Meijide FJ. Gonadal morphogenesis in the South American toad Rhinella Arenarum (Anura, Bufonidae) unveils an extremely delayed rate of sex differentiation. J Morphol 2023; 284:e21611. [PMID: 37458081 DOI: 10.1002/jmor.21611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 05/26/2023] [Accepted: 06/06/2023] [Indexed: 07/18/2023]
Abstract
Among anurans, Bufonids are recognized for their retarded sex differentiation. However, few studies have addressed gonadal morphogenesis in this family. Here, we analyzed the early gonadogenesis in laboratory-reared Rhinella arenarum. Few germ cells were identified in the genital ridge at Gosner stage 26. At metamorphosis, somatic cells and germ cells were observed in the outer region of the undifferentiated gonad, whereas the central region was occupied by stromal tissue. A cortico-medullary organization was first recognized on Day 7 postmetamorphosis. The cortex was composed of germ cells and encompassing epithelial cells, whereas the medulla contained cells presumptively derived from the coelomic epithelium. Medullary somatic cells formed metameric knots along the length of the undifferentiated gonad. Consequently, a series of 12-14 gonomeres became recognizable externally. The first sign of ovarian differentiation was observed on Day 15 postmetamorphosis, when a cavity was formed within each gonomere. In contrast, testes were recognized by a uniform distribution of germ cells and intermingled somatic cells, as the division into cortex and medulla was lost. By Day 50 postmetamorphosis, the gonadal metameric organization was still apparent both in the ovaries and testes. Follicles containing diplotene oocytes were observed within the ovary. In the testis, an incipient lobular architecture was recognized without initiation of meiosis within the seminiferous cords. These observations reveal an extremely delayed gonadal development in R. arenarum, not reported previously for other anuran species. In addition, the late differentiation of the gonads contrasted with the early appearance of follicles in the Bidder's organ. Lastly, we observed that delayed metamorphs exhibited an undifferentiated gonad, demonstrating that gonadogenesis in this species is more dependent on somatic development than on age.
Collapse
Affiliation(s)
- Yanina G Piazza
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Silvia C Czuchlej
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - María L Gómez
- Instituto de Bio y Geociencias del NOA, CONICET, Centro Científico Tecnológico-Salta, Salta, Argentina
| | - Fernando J Meijide
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| |
Collapse
|
9
|
Wen Y, Zhan J, Li C, Li P, Wang C, Wu J, Xu Y, Zhang Y, Zhou Y, Li E, Nie H, Wu X. G-protein couple receptor (GPER1) plays an important role during ovarian folliculogenesis and early development of the Chinese Alligator. Anim Reprod Sci 2023; 255:107295. [PMID: 37422950 DOI: 10.1016/j.anireprosci.2023.107295] [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: 04/13/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/11/2023]
Abstract
The critical role of the G protein-coupled receptor 1 (GPER1), a member of the seven-transmembrane G protein-coupled receptor family, in the functional regulation of oocytes accumulated abundant theories in the early research on model animals. However, the full-length cDNA encoding GPER1 and its role in the folliculogenesis has not been illustrated in crocodilians. 0.5, 3, and 12 months old Alligator sinensis cDNA samples were used to clone the full-length cDNA encoding GPER1. Immunolocalization and quantitative analysis were performed using Immunofluorescence technique, RT-PCR and Western blot. Simultaneously, studies on GPER1's promoter deletion and cis-acting transcriptional regulation mechanism were conducted. Immunolocalization staining for the germline marker DDX4 and GPER1 demonstrated that DDX4-positive oocytes were clustered tightly together within the nests, whereas scarcely any detectable GPER1 was present in the oocytes nest in Stage I. After that, occasionally GPER1-positive immunosignal was observed in oocytes and somatic cells additional with the primordial follicles, and it was mainly located at the granulosa cells or thecal cells within the early PFs in the Stage III. The single mutation of the putative SP1 motif, double mutating of Ets/SP1 and SP1/CRE binding sites all depressed promoter activities. This result will help to investigate the role of GPER1 in the early folliculogenesis of A. sinensis.
Collapse
Affiliation(s)
- Yue Wen
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Jixiang Zhan
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Changcheng Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Pengfei Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Chong Wang
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Jie Wu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yunlu Xu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yuqian Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yongkang Zhou
- Alligator Research Center of Anhui Province, Xuanzhou 242000, People's Republic of China
| | - En Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Haitao Nie
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China.
| | - Xiaobing Wu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China.
| |
Collapse
|
10
|
Zhou Y, Guan J, Meng G, Fan W, Ge C, Niu C, Cheng Y, Fu Y, Lu Y, Wei Y. The RagA GTPase protects young egg chambers in Drosophila. Cell Rep 2023; 42:112631. [PMID: 37302067 DOI: 10.1016/j.celrep.2023.112631] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 04/18/2023] [Accepted: 05/24/2023] [Indexed: 06/13/2023] Open
Abstract
The preservation of female fertility under unfavorable conditions is essential for animal reproduction. Inhibition of the target of rapamycin complex 1 (TORC1) is indispensable for Drosophila young egg chamber maintenance under nutrient starvation. Here, we show that knockdown of RagA results in young egg chamber death independent of TORC1 hyperactivity. RagA RNAi ovaries have autolysosomal acidification and degradation defects, which make the young egg chambers sensitive to autophagosome augmentation. Meanwhile, RagA RNAi ovaries have nuclear-localized Mitf, which promotes autophagic degradation and protects young egg chambers under stress. Interestingly, GDP-bound RagA rescues autolysosome defects, while GTP-bound RagA rescues Mitf nuclear localization in RagA RNAi young egg chambers. Moreover, Rag GTPase activity, rather than TORC1 activity, controls Mitf cellular localization in the Drosophila germ line. Our work suggests that RagA separately controls autolysosomal acidification and Mitf activity in the Drosophila young egg chambers.
Collapse
Affiliation(s)
- Ying Zhou
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Jianwen Guan
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Guoqiang Meng
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Weikang Fan
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Churui Ge
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Chunmei Niu
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Yang Cheng
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Yuanyuan Fu
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Yingying Lu
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
| | - Youheng Wei
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; Institute of Reproduction and Metabolism, Yangzhou University, Yangzhou 225009, China.
| |
Collapse
|
11
|
Ikami K, Shoffner-Beck S, Tyczynska Weh M, Schnell S, Yoshida S, Diaz Miranda EA, Ko S, Lei L. Branched germline cysts and female-specific cyst fragmentation facilitate oocyte determination in mice. Proc Natl Acad Sci U S A 2023; 120:e2219683120. [PMID: 37155904 PMCID: PMC10194012 DOI: 10.1073/pnas.2219683120] [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: 11/17/2022] [Accepted: 04/03/2023] [Indexed: 05/10/2023] Open
Abstract
During mouse gametogenesis, germ cells derived from the same progenitor are connected via intercellular bridges forming germline cysts, within which asymmetrical or symmetrical cell fate occurs in female and male germ cells, respectively. Here, we have identified branched cyst structures in mice, and investigated their formation and function in oocyte determination. In fetal female cysts, 16.8% of the germ cells are connected by three or four bridges, namely branching germ cells. These germ cells are preferentially protected from cell death and cyst fragmentation and accumulate cytoplasm and organelles from sister germ cells to become primary oocytes. Changes in cyst structure and differential cell volumes among cyst germ cells suggest that cytoplasmic transport in germline cysts is conducted in a directional manner, in which cellular content is first transported locally between peripheral germ cells and further enriched in branching germ cells, a process causing selective germ cell loss in cysts. Cyst fragmentation occurs extensively in female cysts, but not in male cysts. Male cysts in fetal and adult testes have branched cyst structures, without differential cell fates between germ cells. During fetal cyst formation, E-cadherin (E-cad) junctions between germ cells position intercellular bridges to form branched cysts. Disrupted junction formation in E-cad-depleted cysts led to an altered ratio in branched cysts. Germ cell-specific E-cad knockout resulted in reductions in primary oocyte number and oocyte size. These findings shed light on how oocyte fate is determined within mouse germline cysts.
Collapse
Affiliation(s)
- Kanako Ikami
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI48109
- Buck Institute for Research on Aging, Novato, CA94945
| | - Suzanne Shoffner-Beck
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Malgorzata Tyczynska Weh
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Santiago Schnell
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI48109
| | - Shosei Yoshida
- Division of Germ Cell Biology, National Institute for Basic Biology, Okazaki, Aichi444-8585, Japan
- Graduate Institute for Advanced Studies, Sokendai, Okazaki, Aichi444-8585, Japan
| | - Edgar Andres Diaz Miranda
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
| | - Sooah Ko
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
| | - Lei Lei
- Department of Obstetrics, Gynecology and Women’s Health, University of Missouri School of Medicine, Columbia, MO65211
- Division of Biological Sciences, College of Arts and Sciences, University of Missouri, Columbia, MO65211
| |
Collapse
|
12
|
Beachum AN, Hinnant TD, Williams AE, Powell AM, Ables ET. β-importin Tnpo-SR promotes germline stem cell maintenance and oocyte differentiation in female Drosophila. Dev Biol 2023; 494:1-12. [PMID: 36450333 PMCID: PMC9870978 DOI: 10.1016/j.ydbio.2022.11.006] [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: 09/22/2021] [Revised: 11/09/2022] [Accepted: 11/21/2022] [Indexed: 11/29/2022]
Abstract
Germ cell development requires interplay between factors that balance cell fate and division. Early in their development, germ cells in many organisms divide mitotically with incomplete cytokinesis. Key regulatory events then lead to the specification of mature gametes, marked by the switch to a meiotic cell cycle program. Though the regulation of germ cell proliferation and meiosis are well understood, how these events are coordinated during development remains incompletely described. Originally characterized in their role as nucleo-cytoplasmic shuttling proteins, β-importins exhibit diverse functions during male and female gametogenesis. Here, we describe novel, distinct roles for the β-importin, Transportin-Serine/Arginine rich (Tnpo-SR), as a regulator of the mitosis to meiosis transition in the Drosophila ovary. We find that Tnpo-SR is necessary for germline stem cell (GSC) establishment and self-renewal, likely by controlling the response of GSCs to bone morphogenetic proteins. Depletion of Tnpo-SR results in germ cell counting defects and loss of oocyte identity. We show that in the absence of Tnpo-SR, proteins typically suppressed in germ cells when they exit mitosis fail to be down-regulated, and oocyte-specific factors fail to accumulate. Together, these findings provide new insight into the balance between germ cell division and differentiation and identify novel roles for β-importins in germ cell development.
Collapse
Affiliation(s)
- Allison N Beachum
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Taylor D Hinnant
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Anna E Williams
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Amanda M Powell
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Elizabeth T Ables
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA.
| |
Collapse
|
13
|
Diegmiller R, Imran Alsous J, Li D, Yamashita YM, Shvartsman SY. Fusome topology and inheritance during insect gametogenesis. PLoS Comput Biol 2023; 19:e1010875. [PMID: 36821548 PMCID: PMC9949678 DOI: 10.1371/journal.pcbi.1010875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 01/16/2023] [Indexed: 02/24/2023] Open
Abstract
From insects to mammals, oocytes and sperm develop within germline cysts comprising cells connected by intercellular bridges (ICBs). In numerous insects, formation of the cyst is accompanied by growth of the fusome-a membranous organelle that permeates the cyst. Fusome composition and function are best understood in Drosophila melanogaster: during oogenesis, the fusome dictates cyst topology and size and facilitates oocyte selection, while during spermatogenesis, the fusome synchronizes the cyst's response to DNA damage. Despite its distinct and sex-specific roles during insect gametogenesis, elucidating fusome growth and inheritance in females and its structure and connectivity in males has remained challenging. Here, we take advantage of advances in three-dimensional (3D) confocal microscopy and computational image processing tools to reconstruct the topology, growth, and distribution of the fusome in both sexes. In females, our experimental findings inform a theoretical model for fusome assembly and inheritance and suggest that oocyte selection proceeds through an 'equivalency with a bias' mechanism. In males, we find that cell divisions can deviate from the maximally branched pattern observed in females, leading to greater topological variability. Our work consolidates existing disjointed experimental observations and contributes a readily generalizable computational approach for quantitative studies of gametogenesis within and across species.
Collapse
Affiliation(s)
- Rocky Diegmiller
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Jasmin Imran Alsous
- Flatiron Institute, Simons Foundation, New York, New York, United States of America
| | - Duojia Li
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Yukiko M. Yamashita
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Howard Hughes Medical Institute, Cambridge, Massachusetts, United States of America
| | - Stanislav Y. Shvartsman
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Flatiron Institute, Simons Foundation, New York, New York, United States of America
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| |
Collapse
|
14
|
Liu S, Baeg GH, Yang Y, Goh FG, Bao H, Wagner EJ, Yang X, Cai Y. The Integrator complex desensitizes cellular response to TGF-β/BMP signaling. Cell Rep 2023; 42:112007. [PMID: 36641752 DOI: 10.1016/j.celrep.2023.112007] [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: 05/02/2022] [Revised: 10/12/2022] [Accepted: 01/03/2023] [Indexed: 01/15/2023] Open
Abstract
Maintenance of stem cells requires the concerted actions of niche-derived signals and stem cell-intrinsic factors. Although Decapentaplegic (Dpp), a Drosophila bone morphogenetic protein (BMP) molecule, can act as a long-range morphogen, its function is spatially limited to the germline stem cell niche in the germarium. We show here that Integrator, a complex known to be involved in RNA polymerase II (RNAPII)-mediated transcriptional regulation in the nucleus, promotes germline differentiation by restricting niche-derived Dpp/BMP activity in the cytoplasm. Further results show that Integrator works in various developmental contexts to desensitize the cellular response to Dpp/BMP signaling during Drosophila development. Mechanistically, our results show that Integrator forms a multi-subunit complex with the type I receptor Thickveins (Tkv) and other Dpp/BMP signaling components and acts in a negative feedback loop to promote Tkv turnover independent of its transcriptional activity. Similarly, human Integrator subunits bind transforming growth factor β (TGF-β)/BMP signaling components and antagonize their activity, suggesting a conserved role of Integrator across metazoans.
Collapse
Affiliation(s)
- Sen Liu
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore
| | - Gyeong Hun Baeg
- Faculty of Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau SAR, China
| | - Ying Yang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore
| | - Feng Guang Goh
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Hongcun Bao
- The Women's Hospital and Institute of Genetics, School of Medicine, Zhejiang University, Hang Zhou 310058, China
| | - Eric J Wagner
- Department of Biochemistry and Biophysics, Center for RNA Biology, Wilmot Cancer Institute, University of Rochester School of Medicine and Dentistry, KMRB B.9629, Rochester, NY 14642 USA
| | - Xiaohang Yang
- The Women's Hospital and Institute of Genetics, School of Medicine, Zhejiang University, Hang Zhou 310058, China
| | - Yu Cai
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
| |
Collapse
|
15
|
Zhang H, Goh FG, Ng LC, Chen CH, Cai Y. Aedes aegypti exhibits a distinctive mode of late ovarian development. BMC Biol 2023; 21:11. [PMID: 36690984 PMCID: PMC9872435 DOI: 10.1186/s12915-023-01511-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 01/05/2023] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Insects live in almost every habitat on earth. To adapt to their diverse environments, insects have developed a myriad of different strategies for reproduction reflected in diverse anatomical and behavioral features that the reproductive systems of females exhibit. Yet, ovarian development remains largely uncharacterized in most species except Drosophila melanogaster (D. melanogaster), a high Diptera model. In this study, we investigated the detailed developmental process of the ovary in Aedes aegypti (Ae. aegypti), a major vector of various disease-causing pathogens that inhabits tropical and subtropical regions. RESULTS Compared with Drosophila melanogaster, a model of higher Diptera, the processes of pole cell formation and gonad establishment during embryonic stage are highly conserved in Ae. aegypti. However, Ae. aegypti utilizes a distinct strategy to form functional ovaries during larval/pupal development. First, during larval stage, Ae. aegypti primordial germ cells (PGCs) undergo a cyst-like proliferation with synchronized divisions and incomplete cytokinesis, leading to the formation of one tightly packed "PGC mass" containing several interconnected cysts, different from D. melanogaster PGCs that divide individually. This cyst-like proliferation is regulated by the target of rapamycin (TOR) pathway upon nutritional status. Second, ecdysone-triggered ovariole formation during metamorphosis exhibits distinct events, including "PGC mass" breakdown, terminal filament cell degeneration, and pre-ovariole migration. These unique developmental features might explain the structural and behavioral differences between Aedes and Drosophila ovaries. Importantly, both cyst-like proliferation and distinct ovariole formation are also observed in Culex quinquefasciatus and Anopheles sinensis, suggesting a conserved mode of ovarian development among mosquito species. In comparison with Drosophila, the ovarian development in Aedes and other mosquitoes might represent a primitive mode in the lower Diptera. CONCLUSIONS Our study reveals a new mode of ovarian development in mosquitoes, providing insights into a better understanding of the reproductive system and evolutionary relationship among insects.
Collapse
Affiliation(s)
- Heng Zhang
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, 117604, Singapore
| | - Feng Guang Goh
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, 117604, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Lee Ching Ng
- Environmental Health Institute, National Environment Agency, 11 Biopolis Way, #06-05/08, Helios Block, Singapore, 138667, Singapore
| | - Chun Hong Chen
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli, 350401, Taiwan
| | - Yu Cai
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, 117604, Singapore.
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore.
| |
Collapse
|
16
|
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.
Collapse
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.
| |
Collapse
|
17
|
Williams AE, Ables ET. Visualizing Fusome Morphology via Tubulin Immunofluorescence in Drosophila Ovarian Germ Cells. Methods Mol Biol 2023; 2626:135-150. [PMID: 36715903 PMCID: PMC10088872 DOI: 10.1007/978-1-0716-2970-3_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In many species, oocytes are initially formed by the mitotic divisions of germline stem cells and their differentiating daughters. These progenitor cells are frequently interconnected in structures called cysts, which may function to safeguard oocyte quality. In Drosophila, an essential germline-specific organelle called the fusome helps maintain and coordinate the mitotic divisions of both germline stem cells and cyst cells. The fusome also serves as a useful experimental marker to identify germ cells during their mitotic divisions. Fusomes are cytoplasmic organelles composed of microtubules, endoplasmic reticulum-derived vesicles, and a meshwork of membrane skeleton proteins. The fusome branches as mitotic divisions progress, traversing the intercellular bridges of germline stem cell/cystoblast pairs and cysts. Here, we provide a protocol to visualize fusome morphology in fixed tissue by stabilizing microtubules and immunostaining for α-Tubulin and other protein constituents of the fusome. We identify a variety of fluorophore-tagged proteins that are useful for visualizing the fusome and describe how these might be combined experimentally. Taken together, these tools provide a valuable resource to interrogate the genetic control of germline stem cell function, oocyte selection, and asymmetric division.
Collapse
Affiliation(s)
- Anna E Williams
- Department of Biology, East Carolina University, Greenville, NC, USA
- Biochemistry, Cell & Developmental Biology Graduate Program, Emory University, Atlanta, GA, USA
| | - Elizabeth T Ables
- Department of Biology, East Carolina University, Greenville, NC, USA.
| |
Collapse
|
18
|
Spradling AC, Niu W, Yin Q, Pathak M, Maurya B. Conservation of oocyte development in germline cysts from Drosophila to mouse. eLife 2022; 11:83230. [PMID: 36445738 PMCID: PMC9708067 DOI: 10.7554/elife.83230] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/17/2022] [Indexed: 11/30/2022] Open
Abstract
Recent studies show that pre-follicular mouse oogenesis takes place in germline cysts, highly conserved groups of oogonial cells connected by intercellular bridges that develop as nurse cells as well as an oocyte. Long studied in Drosophila and insect gametogenesis, female germline cysts acquire cytoskeletal polarity and traffic centrosomes and organelles between nurse cells and the oocyte to form the Balbiani body, a conserved marker of polarity. Mouse oocyte development and nurse cell dumping are supported by dynamic, cell-specific programs of germline gene expression. High levels of perinatal germ cell death in this species primarily result from programmed nurse cell turnover after transfer rather than defective oocyte production. The striking evolutionary conservation of early oogenesis mechanisms between distant animal groups strongly suggests that gametogenesis and early embryonic development in vertebrates and invertebrates share even more in common than currently believed.
Collapse
Affiliation(s)
- Allan C Spradling
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Wanbao Niu
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Qi Yin
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Madhulika Pathak
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Bhawana Maurya
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| |
Collapse
|
19
|
Gerhold AR, Labbé JC, Singh R. Uncoupling cell division and cytokinesis during germline development in metazoans. Front Cell Dev Biol 2022; 10:1001689. [PMID: 36407108 PMCID: PMC9669650 DOI: 10.3389/fcell.2022.1001689] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022] Open
Abstract
The canonical eukaryotic cell cycle ends with cytokinesis, which physically divides the mother cell in two and allows the cycle to resume in the newly individualized daughter cells. However, during germline development in nearly all metazoans, dividing germ cells undergo incomplete cytokinesis and germ cells stay connected by intercellular bridges which allow the exchange of cytoplasm and organelles between cells. The near ubiquity of incomplete cytokinesis in animal germ lines suggests that this is an ancient feature that is fundamental for the development and function of this tissue. While cytokinesis has been studied for several decades, the mechanisms that enable regulated incomplete cytokinesis in germ cells are only beginning to emerge. Here we review the current knowledge on the regulation of germ cell intercellular bridge formation, focusing on findings made using mouse, Drosophila melanogaster and Caenorhabditis elegans as experimental systems.
Collapse
Affiliation(s)
- Abigail R. Gerhold
- Department of Biology, McGill University, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Jean-Claude Labbé
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
- Department of Pathology and Cell Biology, Université de Montréal, Succ. Centre-ville, Montréal, QC, Canada
- *Correspondence: Abigail R. Gerhold, ; Jean-Claude Labbé,
| | - Ramya Singh
- Department of Biology, McGill University, Montréal, QC, Canada
- Institute for Research in Immunology and Cancer (IRIC), Montréal, QC, Canada
| |
Collapse
|
20
|
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.
Collapse
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
| | | |
Collapse
|
21
|
Niu W, Spradling AC. Mouse oocytes develop in cysts with the help of nurse cells. Cell 2022; 185:2576-2590.e12. [PMID: 35623357 DOI: 10.1016/j.cell.2022.05.001] [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: 11/08/2021] [Revised: 03/07/2022] [Accepted: 05/02/2022] [Indexed: 10/18/2022]
Abstract
Mouse germline cysts, on average, develop into six oocytes supported by 24 nurse cells that transfer cytoplasm and organelles to generate a Balbiani body. We showed that between E14.5 and P5, cysts periodically activate some nurse cells to begin cytoplasmic transfer, which causes them to shrink and turnover within 2 days. Nurse cells die by a programmed cell death (PCD) pathway involving acidification, similar to Drosophila nurse cells, and only infrequently by apoptosis. Prior to initiating transfer, nurse cells co-cluster by scRNA-seq with their pro-oocyte sisters, but during their final 2 days, they cluster separately. The genes promoting oocyte development and nurse cell PCD are upregulated, whereas the genes that repress transfer, such as Tex14, and oocyte factors, such as Nobox and Lhx8, are under-expressed. The transferred nurse cell centrosomes build a cytocentrum that establishes a large microtubule aster in the primordial oocyte that organizes the Balbiani body, defining the earliest oocyte polarity.
Collapse
Affiliation(s)
- Wanbao Niu
- Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA
| | - Allan C Spradling
- Howard Hughes Medical Institute Research Laboratories, Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA.
| |
Collapse
|
22
|
Milas A, Telley IA. Polarity Events in the Drosophila melanogaster Oocyte. Front Cell Dev Biol 2022; 10:895876. [PMID: 35602591 PMCID: PMC9117655 DOI: 10.3389/fcell.2022.895876] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Cell polarity is a pre-requirement for many fundamental processes in animal cells, such as asymmetric cell division, axon specification, morphogenesis and epithelial tissue formation. For all these different processes, polarization is established by the same set of proteins, called partitioning defective (Par) proteins. During development in Drosophila melanogaster, decision making on the cellular and organism level is achieved with temporally controlled cell polarization events. The initial polarization of Par proteins occurs as early as in the germline cyst, when one of the 16 cells becomes the oocyte. Another marked event occurs when the anterior–posterior axis of the future organism is defined by Par redistribution in the oocyte, requiring external signaling from somatic cells. Here, we review the current literature on cell polarity events that constitute the oogenesis from the stem cell to the mature egg.
Collapse
Affiliation(s)
- Ana Milas
- *Correspondence: Ana Milas, ; Ivo A. Telley,
| | | |
Collapse
|
23
|
Chen TA, Lin KY, Yang SM, Tseng CY, Wang YT, Lin CH, Luo L, Cai Y, Hsu HJ. Canonical Wnt Signaling Promotes Formation of Somatic Permeability Barrier for Proper Germ Cell Differentiation. Front Cell Dev Biol 2022; 10:877047. [PMID: 35517512 PMCID: PMC9062081 DOI: 10.3389/fcell.2022.877047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/16/2022] [Indexed: 11/22/2022] Open
Abstract
Morphogen-mediated signaling is critical for proper organ development and stem cell function, and well-characterized mechanisms spatiotemporally limit the expression of ligands, receptors, and ligand-binding cell-surface glypicans. Here, we show that in the developing Drosophila ovary, canonical Wnt signaling promotes the formation of somatic escort cells (ECs) and their protrusions, which establish a physical permeability barrier to define morphogen territories for proper germ cell differentiation. The protrusions shield germ cells from Dpp and Wingless morphogens produced by the germline stem cell (GSC) niche and normally only received by GSCs. Genetic disruption of EC protrusions allows GSC progeny to also receive Dpp and Wingless, which subsequently disrupt germ cell differentiation. Our results reveal a role for canonical Wnt signaling in specifying the ovarian somatic cells necessary for germ cell differentiation. Additionally, we demonstrate the morphogen-limiting function of this physical permeability barrier, which may be a common mechanism in other organs across species.
Collapse
Affiliation(s)
- Ting-An Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Kun-Yang Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Shun-Min Yang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
- Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Chen-Yuan Tseng
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Ting Wang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Chi-Hung Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Lichao Luo
- Temasek Life Science Laboratory, National University of Singapore, Singapore, Singapore
| | - Yu Cai
- Temasek Life Science Laboratory, National University of Singapore, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Hwei-Jan Hsu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
- *Correspondence: Hwei-Jan Hsu,
| |
Collapse
|
24
|
Urbisz AZ, Chajec Ł, Małota K, Student S, Sawadro MK, Śliwińska MA, Świątek P. All for one - changes in mitochondrial morphology and activity during syncytial oogenesis. Biol Reprod 2022; 106:1232-1253. [PMID: 35156116 DOI: 10.1093/biolre/ioac035] [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: 07/02/2021] [Revised: 12/23/2021] [Accepted: 02/10/2022] [Indexed: 11/14/2022] Open
Abstract
The syncytial groups of germ cells (germ-line cysts) forming in ovaries of clitellate annelids are an attractive model to study mitochondrial stage-specific changes. Using transmission electron microscopy, serial block-face scanning electron microscopy, and fluorescent microscopy, we analyzed the mitochondria distribution and morphology and the state of membrane potential in female cysts in Enchytraeus albidus. We visualized in 3D at the ultrastructural level mitochondria in cysts at successive stages: 2-celled, 4-celled, 16-celled cysts, and cyst in advanced oogenesis. We found that mitochondria form extensive aggregates - they are fused and connected into large and branched mitochondrial networks. The most extensive networks are formed with up to 10,000 fused mitochondria, whereas individual organelles represent up to 2% of the total mitochondrial volume. We classify such morphology of mitochondria as a dynamic hyperfusion state, and suggest that it can maintain their high activity and intensifies the process of cellular respiration within the syncytial cysts. We found some individual mitochondria undergoing degradation, which implies that damaged mitochondria are removed from networks for their final elimination. As it was shown that growing oocytes possess less active mitochondria than the nurse cells, it suggests that the high activity of mitochondria in the nurse cells and their dynamic hyperfusion state serve the needs of the growing oocyte. Additionally, we measured by calorimetry the total antioxidant capacity of germ-line cysts in comparison to somatic tissue, and it suggests that antioxidative defense systems, together with mitochondrial networks, can effectively protect germ-line mitochondria from damage.
Collapse
Affiliation(s)
- Anna Z Urbisz
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Łukasz Chajec
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Karol Małota
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Sebastian Student
- Institute of Automatic Control, Silesian University of Technology, Gliwice, Poland
| | - Marta K Sawadro
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| | - Małgorzata A Śliwińska
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, Laboratory of Imaging Tissue Structure and Function, Warsaw, Poland
| | - Piotr Świątek
- Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
| |
Collapse
|
25
|
Abstract
In mammals and flies, only one cell in a multicellular female germline cyst becomes an oocyte, but how symmetry is broken to select the oocyte is unknown. Here, we show that the microtubule (MT) minus end-stabilizing protein Patronin/CAMSAP marks the future Drosophila oocyte and is required for oocyte specification. The spectraplakin Shot recruits Patronin to the fusome, a branched structure extending into all cyst cells. Patronin stabilizes more MTs in the cell with the most fusome material. Our data suggest that this weak asymmetry is amplified by Dynein-dependent transport of Patronin-stabilized MTs. This forms a polarized MT network, along which Dynein transports oocyte determinants into the presumptive oocyte. Thus, Patronin amplifies a weak fusome anisotropy to break symmetry and select one cell to become the oocyte.
Collapse
Affiliation(s)
- D. Nashchekin
- The Gurdon Institute and the Department of Genetics, University of Cambridge; Tennis Court Road, Cambridge CB2 1QN, United Kingdom,Corresponding author. ,
| | - L. Busby
- The Gurdon Institute and the Department of Genetics, University of Cambridge; Tennis Court Road, Cambridge CB2 1QN, United Kingdom
| | - M. Jakobs
- The Department of Physiology, Development and Neuroscience, University of Cambridge; Cambridge CB2 3DY, United Kingdom
| | - I. Squires
- The Gurdon Institute and the Department of Genetics, University of Cambridge; Tennis Court Road, Cambridge CB2 1QN, United Kingdom
| | - D. Johnston
- The Gurdon Institute and the Department of Genetics, University of Cambridge; Tennis Court Road, Cambridge CB2 1QN, United Kingdom,Corresponding author. ,
| |
Collapse
|
26
|
Schroeder CM, Tomlin SA, Mejia Natividad I, Valenzuela JR, Young JM, Malik HS. An actin-related protein that is most highly expressed in Drosophila testes is critical for embryonic development. eLife 2021; 10:71279. [PMID: 34282725 PMCID: PMC8291977 DOI: 10.7554/elife.71279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 06/20/2021] [Indexed: 12/25/2022] Open
Abstract
Most actin-related proteins (Arps) are highly conserved and carry out well-defined cellular functions in eukaryotes. However, many lineages like Drosophila and mammals encode divergent non-canonical Arps whose roles remain unknown. To elucidate the function of non-canonical Arps, we focus on Arp53D, which is highly expressed in testes and retained throughout Drosophila evolution. We show that Arp53D localizes to fusomes and actin cones, two germline-specific actin structures critical for sperm maturation, via a unique N-terminal tail. Surprisingly, we find that male fertility is not impaired upon Arp53D loss, yet population cage experiments reveal that Arp53D is required for optimal fitness in Drosophila melanogaster. To reconcile these findings, we focus on Arp53D function in ovaries and embryos where it is only weakly expressed. We find that under heat stress Arp53D-knockout (KO) females lay embryos with reduced nuclear integrity and lower viability; these defects are further exacerbated in Arp53D-KO embryos. Thus, despite its relatively recent evolution and primarily testis-specific expression, non-canonical Arp53D is required for optimal embryonic development in Drosophila.
Collapse
Affiliation(s)
- Courtney M Schroeder
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Sarah A Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Isabel Mejia Natividad
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - John R Valenzuela
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Janet M Young
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| |
Collapse
|
27
|
Shao B, Diegmiller R, Shvartsman SY. Collective oscillations of coupled cell cycles. Biophys J 2021; 120:4242-4251. [PMID: 34197797 DOI: 10.1016/j.bpj.2021.06.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/15/2021] [Accepted: 06/22/2021] [Indexed: 11/19/2022] Open
Abstract
Problems with networks of coupled oscillators arise in multiple contexts, commonly leading to the question about the dependence of network dynamics on network structure. Previous work has addressed this question in Drosophila oogenesis, in which stable cytoplasmic bridges connect the future oocyte to the supporting nurse cells that supply the oocyte with molecules and organelles needed for its development. To increase their biosynthetic capacity, nurse cells enter the endoreplication program, a special form of the cell cycle formed by the iterated repetition of growth and synthesis phases without mitosis. Recent studies have revealed that the oocyte orchestrates nurse cell endoreplication cycles, based on retrograde (oocyte to nurse cells) transport of a cell cycle inhibitor produced by the nurse cells and localized to the oocyte. Furthermore, the joint dynamics of endocycles has been proposed to depend on the intercellular connectivity within the oocyte-nurse cell cluster. We use a computational model to argue that this connectivity guides, but does not uniquely determine the collective dynamics and identify several oscillatory regimes, depending on the timescale of intercellular transport. Our results provide insights into collective dynamics of coupled cell cycles and motivate future quantitative studies of intercellular communication in the germline cell clusters.
Collapse
Affiliation(s)
- Binglun Shao
- Department of Chemical and Biological Engineering, Princeton, New Jersey; Lewis-Sigler Institute for Integrative Genomics, Princeton, New Jersey
| | - Rocky Diegmiller
- Department of Chemical and Biological Engineering, Princeton, New Jersey; Lewis-Sigler Institute for Integrative Genomics, Princeton, New Jersey
| | - Stanislav Y Shvartsman
- Lewis-Sigler Institute for Integrative Genomics, Princeton, New Jersey; Department of Molecular Biology, Princeton University, Princeton, New Jersey; Flatiron Institute, Simons Foundation, New York, New York.
| |
Collapse
|
28
|
Ikami K, Nuzhat N, Abbott H, Pandoy R, Haky L, Spradling AC, Tanner H, Lei L. Altered germline cyst formation and oogenesis in Tex14 mutant mice. Biol Open 2021; 10:269245. [PMID: 34156079 PMCID: PMC8249907 DOI: 10.1242/bio.058807] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 11/24/2022] Open
Abstract
During oocyte differentiation in mouse fetal ovaries, sister germ cells are connected by intercellular bridges, forming germline cysts. Within the cyst, primary oocytes form via gaining cytoplasm and organelles from sister germ cells through germ cell connectivity. To uncover the role of intercellular bridges in oocyte differentiation, we analyzed mutant female mice lacking testis-expressed 14 (TEX14), a protein involved in intercellular bridge formation and stabilization. In Tex14 homozygous mutant fetal ovaries, germ cells divide to form a reduced number of cysts in which germ cells remained connected via syncytia or fragmented cell membranes, rather than normal intercellular bridges. Compared with wild-type cysts, homozygous mutant cysts fragmented at a higher frequency and produced a greatly reduced number of primary oocytes with precocious cytoplasmic enrichment and enlarged volume. By contrast, Tex14 heterozygous mutant germline cysts were less fragmented and generate primary oocytes at a reduced size. Moreover, enlarged primary oocytes in homozygous mutants were used more efficiently to sustain folliculogenesis than undersized heterozygous mutant primary oocytes. Our observations directly link the nature of fetal germline cysts to oocyte differentiation and development. Summary: Altered germline cyst formation and fragmentation due to defective germ cell connectivity leads to changes in oocyte differentiation and development in Tex14 mutant mice.
Collapse
Affiliation(s)
- Kanako Ikami
- Buck Institute for Research on Aging, 94949, Novato, CA, USA
| | - Nafisa Nuzhat
- Department of Cell and Developmental Biology, University of Michigan Medical School, 48109, Ann Arbor, MI, USA
| | - Haley Abbott
- Department of Cell and Developmental Biology, University of Michigan Medical School, 48109, Ann Arbor, MI, USA
| | - Ronald Pandoy
- Buck Institute for Research on Aging, 94949, Novato, CA, USA
| | - Lauren Haky
- Buck Institute for Research on Aging, 94949, Novato, CA, USA
| | - Allan C Spradling
- Department of Embryology, Carnegie Institution for Science, 21218, Baltimore, MD, USA
| | - Heather Tanner
- Buck Institute for Research on Aging, 94949, Novato, CA, USA
| | - Lei Lei
- Buck Institute for Research on Aging, 94949, Novato, CA, USA
| |
Collapse
|
29
|
Bertho S, Clapp M, Banisch TU, Bandemer J, Raz E, Marlow FL. Zebrafish dazl regulates cystogenesis and germline stem cell specification during the primordial germ cell to germline stem cell transition. Development 2021; 148:dev187773. [PMID: 33722898 PMCID: PMC8077517 DOI: 10.1242/dev.187773] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 03/04/2021] [Indexed: 01/14/2023]
Abstract
Fertility and gamete reserves are maintained by asymmetric divisions of the germline stem cells to produce new stem cells or daughters that differentiate as gametes. Before entering meiosis, differentiating germ cells (GCs) of sexual animals typically undergo cystogenesis. This evolutionarily conserved process involves synchronous and incomplete mitotic divisions of a GC daughter (cystoblast) to generate sister cells connected by intercellular bridges that facilitate the exchange of materials to support rapid expansion of the gamete progenitor population. Here, we investigated cystogenesis in zebrafish and found that early GCs are connected by ring canals, and show that Deleted in azoospermia-like (Dazl), a conserved vertebrate RNA-binding protein (Rbp), is a regulator of this process. Analysis of dazl mutants revealed the essential role of Dazl in regulating incomplete cytokinesis, germline cyst formation and germline stem cell specification before the meiotic transition. Accordingly, dazl mutant GCs form defective ring canals, and ultimately remain as individual cells that fail to differentiate as meiocytes. In addition to promoting cystoblast divisions and meiotic entry, dazl is required for germline stem cell establishment and fertility.
Collapse
Affiliation(s)
- Sylvain Bertho
- Department of Cell, Developmental and Regenerative Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place Box 1020 New York, NY 10029-6574, USA
| | - Mara Clapp
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Torsten U. Banisch
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
- New York University School of Medicine, Department of Cell Biology, New York, NY 10012, USA
| | - Jan Bandemer
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Erez Raz
- Institute of Cell Biology Center for Molecular Biology of Inflammation, Von-Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Florence L. Marlow
- Department of Cell, Developmental and Regenerative Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place Box 1020 New York, NY 10029-6574, USA
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| |
Collapse
|
30
|
Abstract
Formation of primordial follicles occurs when germ cell nests break apart and individual oocytes become surrounded by pregranulosa cells. Why mammalian germ cells develop in germ cell nests is not fully understood but recent work has provided evidence that some oocytes serve as nurse cells supporting other oocytes in the cyst. Headway has also been made in understanding interactions that occur between cyst cells that must change as individual oocytes separate to associate with pregranulosa cells. As germ cell nests undergo breakdown some oocytes are lost by programmed cell death that has been attributed to apoptosis, but newer studies have implicated autophagy in counteracting apoptosis to promote cell survival and maintain the ovarian reserve. Work in the past few years has added to already known pathways regulating primordial follicle formation and has identified new players including signaling molecules, transcription factors and RNA binding proteins.
Collapse
|
31
|
Coelho VL, de Brito TF, de Abreu Brito IA, Cardoso MA, Berni MA, Araujo HMM, Sammeth M, Pane A. Analysis of ovarian transcriptomes reveals thousands of novel genes in the insect vector Rhodnius prolixus. Sci Rep 2021; 11:1918. [PMID: 33479356 PMCID: PMC7820597 DOI: 10.1038/s41598-021-81387-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 12/30/2020] [Indexed: 01/29/2023] Open
Abstract
Rhodnius prolixus is a Triatominae insect species and a primary vector of Chagas disease. The genome of R. prolixus has been recently sequenced and partially assembled, but few transcriptome analyses have been performed to date. In this study, we describe the stage-specific transcriptomes obtained from previtellogenic stages of oogenesis and from mature eggs. By analyzing ~ 228 million paired-end RNA-Seq reads, we significantly improved the current genome annotations for 9206 genes. We provide extended 5' and 3' UTRs, complete Open Reading Frames, and alternative transcript variants. Strikingly, using a combination of genome-guided and de novo transcriptome assembly we found more than two thousand novel genes, thus increasing the number of genes in R. prolixus from 15,738 to 17,864. We used the improved transcriptome to investigate stage-specific gene expression profiles during R. prolixus oogenesis. Our data reveal that 11,127 genes are expressed in the early previtellogenic stage of oogenesis and their transcripts are deposited in the developing egg including key factors regulating germline development, genome integrity, and the maternal-zygotic transition. In addition, GO term analyses show that transcripts encoding components of the steroid hormone receptor pathway, cytoskeleton, and intracellular signaling are abundant in the mature eggs, where they likely control early embryonic development upon fertilization. Our results significantly improve the R. prolixus genome and transcriptome and provide novel insight into oogenesis and early embryogenesis in this medically relevant insect.
Collapse
Affiliation(s)
- Vitor Lima Coelho
- Institute of Biomedical Sciences (ICB), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Maira Arruda Cardoso
- Institute of Biomedical Sciences (ICB), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Mateus Antonio Berni
- Institute of Biomedical Sciences (ICB), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Helena Maria Marcolla Araujo
- Institute of Biomedical Sciences (ICB), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Brazil
| | - Michael Sammeth
- Institute of Biophysics Carlos Chagas Filho (IBCCF), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Applied Sciences, Institute of Bioanalysis, Coburg University, Coburg, Germany
| | - Attilio Pane
- Institute of Biomedical Sciences (ICB), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| |
Collapse
|
32
|
Communal living: the role of polyploidy and syncytia in tissue biology. Chromosome Res 2021; 29:245-260. [PMID: 34075512 PMCID: PMC8169410 DOI: 10.1007/s10577-021-09664-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/10/2021] [Accepted: 05/16/2021] [Indexed: 01/22/2023]
Abstract
Multicellular organisms are composed of tissues with diverse cell sizes. Whether a tissue primarily consists of numerous, small cells as opposed to fewer, large cells can impact tissue development and function. The addition of nuclear genome copies within a common cytoplasm is a recurring strategy to manipulate cellular size within a tissue. Cells with more than two genomes can exist transiently, such as in developing germlines or embryos, or can be part of mature somatic tissues. Such nuclear collectives span multiple levels of organization, from mononuclear or binuclear polyploid cells to highly multinucleate structures known as syncytia. Here, we review the diversity of polyploid and syncytial tissues found throughout nature. We summarize current literature concerning tissue construction through syncytia and/or polyploidy and speculate why one or both strategies are advantageous.
Collapse
|
33
|
Tu R, Duan B, Song X, Chen S, Scott A, Hall K, Blanck J, DeGraffenreid D, Li H, Perera A, Haug J, Xie T. Multiple Niche Compartments Orchestrate Stepwise Germline Stem Cell Progeny Differentiation. Curr Biol 2020; 31:827-839.e3. [PMID: 33357404 DOI: 10.1016/j.cub.2020.12.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 11/17/2020] [Accepted: 12/15/2020] [Indexed: 11/28/2022]
Abstract
The niche controls stem cell self-renewal and progenitor differentiation for maintaining adult tissue homeostasis in various organisms. However, it remains unclear whether the niche is compartmentalized to control stem cell self-renewal and stepwise progeny differentiation. In the Drosophila ovary, inner germarial sheath (IGS) cells form a niche for controlling germline stem cell (GSC) progeny differentiation. In this study, we have identified four IGS subpopulations, which form linearly arranged niche compartments for controlling GSC maintenance and multi-step progeny differentiation. Single-cell analysis of the adult ovary has identified four IGS subpopulations (IGS1-IGS4), the identities and cellular locations of which have been further confirmed by fluorescent in situ hybridization. IGS1 and IGS2 physically interact with GSCs and mitotic cysts to control GSC maintenance and cyst formation, respectively, whereas IGS3 and IGS4 physically interact with 16-cell cysts to regulate meiosis, oocyte development, and cyst morphological change. Finally, one follicle cell progenitor population has also been transcriptionally defined for facilitating future studies on follicle stem cell regulation. Therefore, this study has structurally revealed that the niche is organized into multiple compartments for orchestrating stepwise adult stem cell development and has also provided useful resources and tools for further functional characterization of the niche in the future.
Collapse
Affiliation(s)
- Renjun Tu
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Bo Duan
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Xiaoqing Song
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Shiyuan Chen
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Allison Scott
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Kate Hall
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Jillian Blanck
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Dustin DeGraffenreid
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Hua Li
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Anoja Perera
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Jeff Haug
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA
| | - Ting Xie
- Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| |
Collapse
|
34
|
Kaufman RS, Price KL, Mannix KM, Ayers KM, Hudson AM, Cooley L. Drosophila sperm development and intercellular cytoplasm sharing through ring canals do not require an intact fusome. Development 2020; 147:dev.190140. [PMID: 33033119 DOI: 10.1242/dev.190140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 09/28/2020] [Indexed: 12/17/2022]
Abstract
Animal germ cells communicate directly with each other during gametogenesis through intercellular bridges, often called ring canals (RCs), that form as a consequence of incomplete cytokinesis during cell division. Developing germ cells in Drosophila have an additional specialized organelle connecting the cells called the fusome. Ring canals and the fusome are required for fertility in Drosophila females, but little is known about their roles during spermatogenesis. With live imaging, we directly observe the intercellular movement of GFP and a subset of endogenous proteins through RCs during spermatogenesis, from two-cell diploid spermatogonia to clusters of 64 post-meiotic haploid spermatids, demonstrating that RCs are stable and open to intercellular traffic throughout spermatogenesis. Disruption of the fusome, a large cytoplasmic structure that extends through RCs and is important during oogenesis, had no effect on spermatogenesis or male fertility under normal conditions. Our results reveal that male germline RCs allow the sharing of cytoplasmic information that might play a role in quality control surveillance during sperm development.
Collapse
Affiliation(s)
- Ronit S Kaufman
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Kari L Price
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Katelynn M Mannix
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Kathleen M Ayers
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Andrew M Hudson
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Lynn Cooley
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA .,Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA.,Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT 06511, USA
| |
Collapse
|
35
|
Chanet S, Huynh JR. Collective Cell Sorting Requires Contractile Cortical Waves in Germline Cells. Curr Biol 2020; 30:4213-4226.e4. [PMID: 32916115 DOI: 10.1016/j.cub.2020.08.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 07/01/2020] [Accepted: 08/12/2020] [Indexed: 12/11/2022]
Abstract
Encapsulation of germline cells by layers of somatic cells forms the basic unit of female reproduction called primordial follicles in mammals and egg chambers in Drosophila. How germline and somatic tissues are coordinated for the morphogenesis of each separated unit remains poorly understood. Here, using improved live imaging of Drosophila ovaries, we uncovered periodic actomyosin waves at the cortex of germ cells. These contractile waves are associated with pressure release blebs, which project from germ cells into somatic cells. We demonstrate that these cortical activities, together with cadherin-based adhesion, are required to sort each germline cyst as one collective unit. Genetic perturbations of cortical contractility, bleb protrusion, or adhesion between germline and somatic cells induced encapsulation defects resulting from failures to encapsulate any germ cells, or the inclusion of too many germ cells per egg chamber, or even the mechanical split of germline cysts. Live-imaging experiments revealed that reducing contractility or adhesion in the germline reduced the stiffness of germline cysts and their proper anchoring to the somatic cells. Germline cysts can then be squeezed and passively pushed by constricting surrounding somatic cells, resulting in cyst splitting and cyst collisions during encapsulation. Increasing germline cysts activity or blocking somatic cell constriction movements can reveal active forward migration of germline cysts. Our results show that germ cells play an active role in physical coupling with somatic cells to produce the female gamete.
Collapse
Affiliation(s)
- Soline Chanet
- Center for Interdisciplinary Research in Biology, Collège de France, PSL Research University, CNRS/UMR 7241 - INSERM U1050, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Jean-René Huynh
- Center for Interdisciplinary Research in Biology, Collège de France, PSL Research University, CNRS/UMR 7241 - INSERM U1050, 11 Place Marcelin Berthelot, 75005 Paris, France.
| |
Collapse
|
36
|
Carvalho-Santos Z, Cardoso-Figueiredo R, Elias AP, Tastekin I, Baltazar C, Ribeiro C. Cellular metabolic reprogramming controls sugar appetite in Drosophila. Nat Metab 2020; 2:958-973. [PMID: 32868922 DOI: 10.1038/s42255-020-0266-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 07/17/2020] [Indexed: 12/13/2022]
Abstract
Cellular metabolic reprogramming is an important mechanism by which cells rewire their metabolism to promote proliferation and cell growth. This process has been mostly studied in the context of tumorigenesis, but less is known about its relevance for nonpathological processes and how it affects whole-animal physiology. Here, we show that metabolic reprogramming in Drosophila female germline cells affects nutrient preferences of animals. Egg production depends on the upregulation of the activity of the pentose phosphate pathway in the germline, which also specifically increases the animal's appetite for sugar, the key nutrient fuelling this metabolic pathway. We provide functional evidence that the germline alters sugar appetite by regulating the expression of the fat-body-secreted satiety factor Fit. Our findings demonstrate that the cellular metabolic program of a small set of cells is able to increase the animal's preference for specific nutrients through inter-organ communication to promote specific metabolic and cellular outcomes.
Collapse
Affiliation(s)
- Zita Carvalho-Santos
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal.
| | - Rita Cardoso-Figueiredo
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Ana Paula Elias
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Ibrahim Tastekin
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Célia Baltazar
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Carlos Ribeiro
- Behavior and Metabolism Laboratory, Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon, Portugal.
| |
Collapse
|
37
|
Grive KJ. Pathways coordinating oocyte attrition and abundance during mammalian ovarian reserve establishment. Mol Reprod Dev 2020; 87:843-856. [PMID: 32720428 DOI: 10.1002/mrd.23401] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/16/2020] [Indexed: 12/21/2022]
Abstract
The mammalian ovarian reserve is comprised of a finite pool of primordial follicles, representing the lifetime reproductive capacity of females. In most mammals, the reserve is produced during embryonic and early postnatal development with oocyte numbers peaking during mid-to-late gestation, and then experiencing a dramatic decline continuing until shortly after birth. Oocytes remaining after the bulk of this attrition are subsequently surrounded by a layer of somatic pre-granulosa cells with these units then referred to as "primordial follicles." The complex and varied cell death mechanisms intrinsic to this process are not only characteristic of, but also essential for, the proper formation of this pool of follicles, and as a result must be immaculately balanced to ensure long-term fertility and reproductive health. Too few follicles can lead to Primary Ovarian Insufficiency, resulting in fertility loss and other features of aging, such as an overall shorter lifespan. On the other hand, whereas an excess of follicles might extend reproductive lifespan, this might also be the underlying etiology of other ovarian pathologies. The last decade, in particular, has vastly expanded our understanding of oocyte attrition and determinants of ovarian reserve abundance. By continuing to decipher the intricacies underlying the cell death processes and development of the initial primordial follicle pool, we may be in a much better position to understand idiopathic cases of premature follicle depletion and improve ovarian health in reproductive-age women.
Collapse
Affiliation(s)
- Kathryn J Grive
- Department of Obstetrics and Gynecology, Program in Women's Oncology, Women and Infants Hospital of Rhode Island, Providence, Rhode Island.,Department of Obstetrics and Gynecology, Warren Alpert Medical School of Brown University, Providence, Rhode Island
| |
Collapse
|
38
|
Gonadal development and sex determination in mouse. Reprod Biol 2020; 20:115-126. [DOI: 10.1016/j.repbio.2020.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 01/21/2020] [Accepted: 01/25/2020] [Indexed: 12/18/2022]
|
39
|
Eastin KJ, Huang AP, Ferree PM. A novel pattern of germ cell divisions in the production of hymenopteran insect eggs. Biol Lett 2020; 16:20200137. [PMID: 32396789 DOI: 10.1098/rsbl.2020.0137] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Egg development is a defining process of reproduction in higher eukaryotes. In the fruit fly, Drosophila melanogaster, this process begins with four mitotic divisions starting from a single germ cell, producing a cyst of 16 cystocytes; one of these cells will become the oocyte and the others supporting nurse cells. These mitotic divisions are exceptional because cytokinesis is incomplete, resulting in the formation of cytoplasmic bridges known as ring canals that interconnect the cystocytes. This organization allows all cystocytes to divide synchronously during each mitotic round, resulting in a final, power-of-2 number of germ cells. Given that numerous insects obey this power-of-2 rule, we investigated if strict cell doubling is a universal, underlying cause. Using confocal microscopy, we found striking departures from this paradigm in three different power-of-2 insects belonging to the Apocrita suborder (ants, bees and wasps). In these insects, the earliest-formed cystocytes cease to divide during the latter mitotic cycles while their descendants undergo further division, thereby producing a 'radial' direction of division activity. Such cystocyte division patterns that depart from strict cell doubling may be 'fine-tuned' in order to maintain a final, power-of-2 germ cell number.
Collapse
Affiliation(s)
- Katherine J Eastin
- W. M. Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, CA 91711, USA
| | - Austin P Huang
- W. M. Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, CA 91711, USA
| | - Patrick M Ferree
- W. M. Keck Science Department, Claremont McKenna, Pitzer and Scripps Colleges, Claremont, CA 91711, USA
| |
Collapse
|
40
|
Świątek P, Pinder A, Gajda Ł. Description of ovary organization and oogenesis in a phreodrilid clitellate. J Morphol 2019; 281:81-94. [DOI: 10.1002/jmor.21081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/22/2019] [Accepted: 10/25/2019] [Indexed: 01/09/2023]
Affiliation(s)
- Piotr Świątek
- Department of Animal Histology and EmbryologyUniversity of Silesia in Katowice Katowice Poland
| | - Adrian Pinder
- Biodiversity and Conservation Science, Department of BiodiversityConservation and Attractions Kensington Western Australia Australia
| | - Łukasz Gajda
- Department of Animal Histology and EmbryologyUniversity of Silesia in Katowice Katowice Poland
| |
Collapse
|
41
|
Rosario R, Crichton JH, Stewart HL, Childs AJ, Adams IR, Anderson RA. Dazl determines primordial follicle formation through the translational regulation of Tex14. FASEB J 2019; 33:14221-14233. [PMID: 31659914 DOI: 10.1096/fj.201901247r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Deleted in azoospermia-like (DAZL) is a germ cell RNA-binding protein that is essential for entry and progression through meiosis. The phenotype of the Dazl knockout mouse has extensive germ cell loss because of incomplete meiosis. We have created a Dazl hypomorph model using short interfering RNA knockdown in mouse fetal ovary cultures, allowing investigation of Dazl function in germ cell maturation. Dazl hypomorph ovaries had a phenotype of impaired germ cell nest breakdown with a 66% reduction in total follicle number and an increase in the proportion of primordial follicles (PMFs), with smaller oocytes within these follicles. There was no significant early germ cell loss or meiotic delay. Immunostaining of intercellular bridge component testis-expressed protein (Tex)14 showed ∼59% reduction in foci number and size, without any change in Tex14 mRNA levels. TEX14 expression was also confirmed in the human fetal ovary across gestation. Using 3'UTR-luciferase reporter assays, translational regulation of TEX14 was demonstrated to be DAZL-dependant. Dazl is therefore essential for normal intercellular bridges within germ cell nests and their timely breakdown, with a major impact on subsequent assembly of PMFs.-Rosario, R., Crichton, J. H., Stewart, H. L., Childs, A. J., Adams, I. R., Anderson, R. A. Dazl determines primordial follicle formation through the translational regulation of Tex14.
Collapse
Affiliation(s)
- Roseanne Rosario
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - James H Crichton
- Medical Research Council (MRC) Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, United Kingdom
| | - Hazel L Stewart
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew J Childs
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Ian R Adams
- Medical Research Council (MRC) Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, United Kingdom
| | - Richard A Anderson
- Medical Research Council (MRC) Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
42
|
Wei Y, Bettedi L, Ting CY, Kim K, Zhang Y, Cai J, Lilly MA. The GATOR complex regulates an essential response to meiotic double-stranded breaks in Drosophila. eLife 2019; 8:e42149. [PMID: 31650955 PMCID: PMC6834368 DOI: 10.7554/elife.42149] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/13/2019] [Indexed: 01/18/2023] Open
Abstract
The TORC1 regulator GATOR1/SEACIT controls meiotic entry and early meiotic events in yeast. However, how metabolic pathways influence meiotic progression in metazoans remains poorly understood. Here we examine the role of the TORC1 regulators GATOR1 and GATOR2 in the response to meiotic double-stranded breaks (DSB) during Drosophila oogenesis. We find that in mutants of the GATOR2 component mio, meiotic DSBs trigger the constitutive downregulation of TORC1 activity and a permanent arrest in oocyte growth. Conversely, in GATOR1 mutants, high TORC1 activity results in the delayed repair of meiotic DSBs and the hyperactivation of p53. Unexpectedly, we found that GATOR1 inhibits retrotransposon expression in the presence of meiotic DSBs in a pathway that functions in parallel to p53. Thus, our studies have revealed a link between oocyte metabolism, the repair of meiotic DSBs and retrotransposon expression.
Collapse
Affiliation(s)
- Youheng Wei
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
- College of Bioscience and BiotechnologyYangzhou UniversityYangzhouChina
| | - Lucia Bettedi
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
| | - Chun-Yuan Ting
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
| | - Kuikwon Kim
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
| | - Yingbiao Zhang
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
| | - Jiadong Cai
- College of Bioscience and BiotechnologyYangzhou UniversityYangzhouChina
| | - Mary A Lilly
- Cell Biology and Neurobiology BranchNational Institute of Child Health and Human Development, National Institutes of HealthBethesdaUnited States
| |
Collapse
|
43
|
Li M, Hu X, Zhang S, Ho MS, Wu G, Zhang L. Traffic jam regulates the function of the ovarian germline stem cell progeny differentiation niche during pre-adult stage in Drosophila. Sci Rep 2019; 9:10124. [PMID: 31300663 PMCID: PMC6626045 DOI: 10.1038/s41598-019-45317-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 03/29/2019] [Indexed: 11/28/2022] Open
Abstract
Stem cell self-renewal and the daughter cell differentiation are tightly regulated by the respective niches, which produce extrinsic cues to support the proper development. In Drosophila ovary, Dpp is secreted from germline stem cell (GSC) niche and activates the BMP signaling in GSCs for their self-renewal. Escort cells (ECs) in differentiation niche restrict Dpp outside the GSC niche and extend protrusions to help with proper differentiation of the GSC daughter cells. Here we provide evidence that loss of large Maf transcriptional factor Traffic jam (Tj) blocks GSC progeny differentiation. Spatio-temporal specific knockdown experiments indicate that Tj is required in pre-adult EC lineage for germline differentiation control. Further molecular and genetic analyses suggest that the defective germline differentiation caused by tj-depletion is partly attributed to the elevated dpp in the differentiation niche. Moreover, our study reveals that tj-depletion induces ectopic En expression outside the GSC niche, which contributes to the upregulated dpp expression in ECs as well as GSC progeny differentiation defect. Alternatively, loss of EC protrusions and decreased EC number elicited by tj-depletion may also partially contribute to the germline differentiation defect. Collectively, our findings suggest that Tj in ECs regulates germline differentiation by controlling the differentiation niche characteristics.
Collapse
Affiliation(s)
- Mengjie Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaolong Hu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shu Zhang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Margaret S Ho
- School of Life Science and Technology, Shanghai Tech University, Shanghai, 201210, China
| | - Geng Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Lei Zhang
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Innovation Center for Cell Signaling Network, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China. .,School of Life Science and Technology, Shanghai Tech University, Shanghai, 201210, China.
| |
Collapse
|
44
|
Heterochromatin protein 1 (HP1) is intrinsically required for post-transcriptional regulation of Drosophila Germline Stem Cell (GSC) maintenance. Sci Rep 2019; 9:4372. [PMID: 30867469 PMCID: PMC6416348 DOI: 10.1038/s41598-019-40152-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 02/07/2019] [Indexed: 01/05/2023] Open
Abstract
A very important open question in stem cells regulation is how the fine balance between GSCs self-renewal and differentiation is orchestrated at the molecular level. In the past several years much progress has been made in understanding the molecular mechanisms underlying intrinsic and extrinsic controls of GSC regulation but the complex gene regulatory networks that regulate stem cell behavior are only partially understood. HP1 is a dynamic epigenetic determinant mainly involved in heterochromatin formation, epigenetic gene silencing and telomere maintenance. Furthermore, recent studies have revealed the importance of HP1 in DNA repair, sister chromatid cohesion and, surprisingly, in positive regulation of gene expression. Here, we show that HP1 plays a crucial role in the control of GSC homeostasis in Drosophila. Our findings demonstrate that HP1 is required intrinsically to promote GSC self-renewal and progeny differentiation by directly stabilizing the transcripts of key genes involved in GSCs maintenance.
Collapse
|
45
|
Ben-Zvi DS, Volk T. Escort cell encapsulation of Drosophila germline cells is maintained by irre cell recognition module proteins. Biol Open 2019; 8:bio039842. [PMID: 30837217 PMCID: PMC6451344 DOI: 10.1242/bio.039842] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Accepted: 02/06/2019] [Indexed: 12/17/2022] Open
Abstract
Differentiation of germline stem cells (GSCs) in the Drosophila ovary is induced by somatic escort cells (ECs), which extend membrane protrusions encapsulating the germline cells (GCs). Germline encapsulation requires activated epidermal growth factor receptor (Egfr) signaling within the ECs, following secretion of its ligands from the GCs. We show that the conserved family of irre cell recognition module (IRM) proteins is essential for GC encapsulation by ECs, with a requirement for roughest (rst) and kin of irre (kirre) in the germline and for sticks and stones (sns) and hibris (hbs) in ECs. In the absence of IRM components in their respective cell types, EC extensions are reduced concomitantly with a decrease in Egfr signaling in these cells. Reintroducing either activated Egfr in the ECs, or overexpressing its ligand Spitz (Spi) from the germline, rescued the requirement for IRM proteins in both cell types. These experiments introduce novel essential components, the IRM proteins, into the process of inductive interactions between GCs and ECs, and imply that IRM-mediated activity is required upstream of the Egfr signaling.
Collapse
Affiliation(s)
- Doreen S Ben-Zvi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Talila Volk
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
46
|
Świątek P, Urbisz AZ. Architecture and Life History of Female Germ-Line Cysts in Clitellate Annelids. Results Probl Cell Differ 2019; 68:515-551. [PMID: 31598870 DOI: 10.1007/978-3-030-23459-1_21] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Animal female and male germ-line cells often form syncytial units termed cysts, clusters, or clones. Within these cysts, the cells remain interconnected by specific cell junctions known as intercellular bridges or ring canals, which enable cytoplasm to be shared and macromolecules and organelles to be exchanged between cells. Numerous analyses have shown that the spatial organization of cysts and their functioning may differ between the sexes and taxa. The vast majority of our knowledge about the formation and functioning of germ-line cysts comes from studies of model species (mainly Drosophila melanogaster); the other systems of the cyst organization and functioning are much less known and are sometimes overlooked. Here, we present the current state of the knowledge of female germ-line cysts in clitellate annelids (Clitellata), which is a monophyletic taxon of segmented worms (Annelida). The organization of germ-line cysts in clitellates differs markedly from that of the fruit fly and vertebrates. In Clitellata, germ cells are not directly connected one to another, but, as a rule, each cell has one ring canal that connects it to an anuclear central cytoplasmic core, a cytophore. Thus, this pattern of cell distribution is similar to the germ-line cysts of Caenorhabditis elegans. The last decade of studies has revealed that although clitellate female germ-line cysts have a strong morphological plasticity, e.g., cysts may contain from 16 to as many as 2500 cells, the oogenesis always shows a meroistic mode, i.e., the interconnected cells take on different fates; a few (sometimes only one) become oocytes, whereas the rest play the role of supporting (nurse) cells and do not continue oogenesis.This is the first comprehensive summary of the current knowledge on the organization and functioning of female germ-line cysts in clitellate annelids.
Collapse
Affiliation(s)
- Piotr Świątek
- Faculty of Biology and Environmental Protection, Department of Animal Histology and Embryology, University of Silesia in Katowice, Katowice, Poland.
| | - Anna Z Urbisz
- Faculty of Biology and Environmental Protection, Department of Animal Histology and Embryology, University of Silesia in Katowice, Katowice, Poland
| |
Collapse
|
47
|
Pieper KE, Unckless RL, Dyer KA. A fast-evolving X-linked duplicate of importin-α2 is overexpressed in sex-ratio drive in Drosophila neotestacea. Mol Ecol 2018; 27:5165-5179. [PMID: 30411843 DOI: 10.1111/mec.14928] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/21/2018] [Accepted: 10/25/2018] [Indexed: 01/31/2023]
Abstract
Selfish genetic elements that manipulate gametogenesis to achieve a transmission advantage are known as meiotic drivers. Sex-ratio X chromosomes (SR) are meiotic drivers that prevent the maturation of Y-bearing sperm in male carriers to result in the production of mainly female progeny. The spread of an SR chromosome can affect host genetic diversity and genome evolution, and can even cause host extinction if it reaches sufficiently high prevalence. Meiotic drivers have evolved independently many times, though only in a few cases is the underlying genetic mechanism known. In this study we use a combination of transcriptomics and population genetics to identify widespread expression differences between the standard (ST) and sex-ratio (SR) X chromosomes of the fly Drosophila neotestacea. We found the X chromosome is enriched for differentially expressed transcripts and that many of these X-linked differentially expressed transcripts had elevated Ka /Ks values between ST and SR, indicative of potential functional differences. We identified a set of candidate transcripts, including a testis-specific, X-linked duplicate of the nuclear transport gene importin-α2 that is overexpressed in SR. We find suggestions of positive selection in the lineage leading to the duplicate and that its molecular evolutionary patterns are consistent with relaxed purifying selection in ST. As these patterns are consistent with involvement in the mechanism of drive in this species, this duplicate is a strong candidate worthy of further functional investigation. Nuclear transport may be a common target for genetic conflict, as the mechanism of the autosomal Segregation Distorter drive system in D. melanogaster involves the same pathway.
Collapse
Affiliation(s)
| | - Robert L Unckless
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas
| | - Kelly A Dyer
- Department of Genetics, University of Georgia, Athens, Georgia
| |
Collapse
|
48
|
Yang SY, Lee HJ, Lee HC, Hwang YS, Park YH, Ono T, Han JY. The dynamic development of germ cells during chicken embryogenesis. Poult Sci 2018; 97:650-657. [PMID: 29126291 DOI: 10.3382/ps/pex316] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 09/25/2017] [Indexed: 01/05/2023] Open
Abstract
Appropriate regulation of cell proliferation during embryogenesis is crucial for the maintenance of germness. An in-depth understanding of germ cell developmental processes may yield valuable information on germ cell biology and applied sciences. However, direct evidences about germ cell proliferation and cell cycling during avian embryonic development has not been well-studied. Thus, we explored chicken germ cell dynamics during embryonic development via flow cytometry employing a germ cell-specific anti-cVASA antibody (the chicken VASA homolog is termed CVH) and propidium iodide staining. The numbers of male germ cells increased significantly during early embryonic development, but proliferation was decreased significantly with accumulation at the G0/G1 phase after embryonic d 14 (E.14), indicating initiation of mitotic arrest in the testis. On the other hand, the number of female germ cells increased significantly throughout embryogenesis, and proliferating cells were continuously evident in the ovary to the time of hatching, although gradual accumulation of cells at the G2/M phase was also evident. 5-ethynyl-2΄-deoxyuridine (EdU) incorporation analysis revealed that populations of mitotically active germ cells existed in both sexes during late embryogenesis, indicating either the maintenance of stem cell populations, or asynchronous meiosis. Collectively, these results indicate that chicken germ cells exhibited conserved developmental processes that were clearly sexually dimorphic.
Collapse
Affiliation(s)
- Seo Yeong Yang
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Hong Jo Lee
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Hyung Chul Lee
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Young Sun Hwang
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Young Hyun Park
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
| | - Tamao Ono
- Division of Animal Science Faculty of Agriculture, Shinshu University, 8304 Minamiminowa, Nagano 399-4598, Japan
| | - Jae Yong Han
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.,Institute for Biomedical Sciences, Shinshu University, Minamiminowa, Nagano 399-4598, Japan
| |
Collapse
|
49
|
Herrera SC, Bach EA. JNK signaling triggers spermatogonial dedifferentiation during chronic stress to maintain the germline stem cell pool in the Drosophila testis. eLife 2018; 7:e36095. [PMID: 29985130 PMCID: PMC6070334 DOI: 10.7554/elife.36095] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/06/2018] [Indexed: 12/15/2022] Open
Abstract
Exhaustion of stem cells is a hallmark of aging. In the Drosophila testis, dedifferentiated germline stem cells (GSCs) derived from spermatogonia increase during lifespan, leading to the model that dedifferentiation counteracts the decline of GSCs in aged males. To test this, we blocked dedifferentiation by mis-expressing the differentiation factor bag of marbles (bam) in spermatogonia while lineage-labeling these cells. Strikingly, blocking bam-lineage dedifferentiation under normal conditions in virgin males has no impact on the GSC pool. However, in mated males or challenging conditions, inhibiting bam-lineage dedifferentiation markedly reduces the number of GSCs and their ability to proliferate and differentiate. We find that bam-lineage derived GSCs have significantly higher proliferation rates than sibling GSCs in the same testis. We determined that Jun N-terminal kinase (JNK) activity is autonomously required for bam-lineage dedifferentiation. Overall, we show that dedifferentiation provides a mechanism to maintain the germline and ensure fertility under chronically stressful conditions.
Collapse
Affiliation(s)
| | - Erika A Bach
- New York University School of MedicineNew YorkUnited States
- Helen L. and Martin S. Kimmel Center for Stem Cell BiologyNew York University School of MedicineNew YorkUnited States
| |
Collapse
|
50
|
Urbisz AZ, Chajec Ł, Ito M, Ito K. The ovary organization in the marine limnodriloidin Thalassodrilides cf. briani (Annelida: Clitellata: Naididae) resembles the ovary of freshwater tubificins. ZOOLOGY 2018; 128:16-26. [DOI: 10.1016/j.zool.2018.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 05/09/2018] [Accepted: 05/11/2018] [Indexed: 01/05/2023]
|