The Drosophila testis stem cell niche consists of a cluster of non-mitotic somatic cells called the hub, which produces signals that maintain surrounding GSCs as well as cyst stem cells (CySCs). Here we report that efferent octopaminergic neurons projecting to the ovary are essential for germline stem cell (GSC) increase in response to mating in female Drosophila. The Drosophila melanogaster ovary contains three stem cell populations, germline stem cells (GSCs), escort stem cells (ESCs), and follicle stem cells (FSCs), that reside at the anterior end of the ovary in a structure called a germarium (Harrison and Harrison, 2006). Drosophila ovary is recognized as one of the best model systems to study stem cell biology in vivo. Yb regulates the proliferation of both germline and somatic stem cells in the Drosophila melanogaster ovary by activating piwi and hh expression in niche cells. c587 GAL4 drives strong transgene expression in escort cells (arrowhead) and follicle cells in region 2° (A, magenta arrow), weaker expression is also seen in region 3 follicle cells (A, turquoise arrow). describe a pathway that couples production of ribosomal proteins and cell-cycle progression to allow for female Drosophila GSCs to successfully differentiate. In mammals, an organism consists mainly of two cell types, somatic cells, and germ cells. We show that, in Drosophila, female germline stem cells (GSCs) exhibit heterogeneous expression of a GSC differentiation-promoting factor. Each ovariole contains a linear array of egg chambers composed of germ cells and somatic cells. In the germarium of the Drosophila ovary, developing germline cysts are surrounded by a population of somatic escort cells that are known to function as the niche cells for germline differentiation; 1 however, the underlying molecular mechanisms of this niche function remain poorly understood. ECs extend long protrusions. A GSC divides to generate a self‐renewing stem cell that remains in the niche and a differentiating daughter that moves away from the niche. GSC produces one self-renewing daughter and one cystoblast (CB) that differentiates into a germline cyst. , Peking University, 2010. The somatic cells include escort cells (ECs) located at the anterior end of the egg chamber. Less is known, however, regarding how stem cell activity is regulated by sys-temic, tissue-extrinsic signals in response to environmental cues and changes in physiological status. Drosophila ovarian germline stem cells (GSCs) are a productive adult stem cell system for revealing regulatory mechanisms controlling self-renewal and differentiation. , 2005 ). 10. The Drosophila Female Germline Stem Cell Lineage Acts to Spatially Restrict DPP Function Within the Niche. In males, GSCs physically associate with 10–15 somatic hub cells, which also house a second stem cell population, the somatic cyst stem cells (CySCs). The Drosophila germarium can undergo development in vitro. In Drosophila, reciprocal signals between germline and escort (in female) or somatic cyst (in male) cells can inhibit reversion to the stem cell state (Brawley and Matunis, 2004; Kai and Spradling, 2004) and restrict germ cell proliferation and cyst growth (Matunis et al, 1997). Drosophila have two ovaries, each comprised of roughly 15 ovarioles. The Drosophila adult female gonad comprises a pair of ovaries, each consisting of 16 ovarioles []. Since GSCs are the fundamental cell population for successful reproduction, how such special GSCs are precisely proliferated is a long-standing question in biology. In Drosophila gonads, the stem cell niche—the cap cell cluster in females. In Drosophila ovarian germarium, somatic cap cells form a dish-like niche structure that allows only two or three germ-line stem cells (GSCs) reside in the niche. Dpp is produced in CpCs in response to Janus kinase/signal. Oogenesis in Drosophila occurs in the germarium (plural: germaria), which houses two kinds of stem cells: germline stem cells (GSCs) and follicle stem cells (FSCs) (Figure 1). Each Drosophila ovary is comprised of ovarioles or strings of progressively more developed egg chambers (Fig. In support of this, in cultured Drosophila cells it has been shown that Dilps 2 and 5 elicit different downstream effects upon binding to InR . In this study, we show that Yb protein is localized as discrete cytoplasmic spots exclusively in the somatic cells of the ovary and testis. Multiple signaling pathways guide the behavior and differentiation of both germline stem cells (GSCs) and somatic follicle stem cells (FSCs) in the Drosophila germarium, necessitating careful control of signal generation, range and responses. Early oocyte development takes place in germline cysts and is strikingly conserved from Drosophila to mouse, reflecting common mechanisms that may help reverse aging and. Wnt signaling is a conserved regulator of stem cell behaviors, and the Drosophila germarium has been an important model tissue for the study of stem cell maintenance, differentiation, and proliferation. Similarly, depletion of histone H1 in escort cells also leads to abnormal BMP signaling in germline cells and tumorigenesis. The niche produces local signals such as the bone morphogenetic protein (BMP) ligand Decapentaplegic (Dpp), which activates its receptors Saxophone (Sax), Punt (Put), and Thickveins (Tkv) expressed in. In the Drosophila ovary, germline stem cells (GSCs) physically interact with their niche composed of terminal filament cells, cap cells, and possibly GSC-contacting escort cells (ECs). Here, we show that, in a. Anterior escort cells are maintained by Wnt6 ligands produced by cap cells; without Wnt6 signaling, anterior escort cells die leaving vacancies in the niche, leading to loss of germline stem cells. Xie T: Self-maintained escort cells form a germline stem cell differentiation niche. Stem cell niches provide localized signaling molecules to promote stem cell fate and to suppress differentiation. Nuclear receptors linking physiology and germline stem cells in Drosophila - ScienceDirect Vitamins and Hormones Volume 116, 2021, Pages 327-362 Chapter. Previously, it was observed that the continuous selection of cyromazine from the larval to the adult stage decreased the number of germline stem cells (GSCs) and cystoblasts (CBs) in the adult ovary. GSC progeny differentiation which ultimately generates a terminally differentiated egg is a stepwise process involving both cell-autonomous mechanisms and intercellular communications. elegans and Drosophila, are among the best understood adult stem cell types, and have provided important models for study of the regulation of adult stem cell behavior in vivo. ydbio. Signal integration involves escort cells (ECs), which promote differentiation of the GSC derivatives. Intriguingly,. Drosophila female germline stem and daughter cells. Drosophila female germline stem cells (GSCs) are found inside the cellular niche at the tip of the ovary. The niche is structurally and functionally complex and contains four cell types, the escort, cap, and terminal filament cells and the newly identified transition cell. Surprisingly little is known, however, about the mechanisms that pattern this niche,. GSC division produces one self-renewing daughter and one cystoblast (CB) that differentiates into a germline cyst. Drosophila stem cell niches were made accessible to study by genetic tools that allow individual cells to be lineage labeled, and enable gene function to be disrupted. ) (B) Male germline stem cell lineage in Drosophila. Jin et al. Ovarian germline stem cells (GSCs) of Drosophila melanogaster provide a valuable in vivo model to investigate how the adult stem cell identity is maintained and the differentiation of the daughter cells is regulated. In males, GSCs physically associate with 10–15 somatic hub cells, which also house a second stem cell population, the somatic cyst stem cells (CySCs). . A regulatory network of Drosophila germline stem cell self-renewal. Male and female germline; germ cells, cyst cells, escort cells, cap cells, & follicle cells Open in a separate window In addition, the NURF complex interacts with the Ecdysone (Ecd). Concluding Remarks. (A) The adult ovary of Drosophila consists of 16–20 ovarioles, and the germarium of each ovariole has different types of cells. The Drosophila ovary is a widely used model for germ cell and somatic tissue biology. germline stem cells. Insulin-independent role of adiponectin receptor signaling in Drosophila germline stem cell maintenance. Two different compartments support germline stem cell (GSC) self-renewal and their timely differentiation: the classical niche provides maintenance cues, while a differentiation compartment, formed by somatic escort cells (ECs), is required for proper GSC differentiation. Male GSCs reside in a. The Drosophila follicular epithelium is a genetically tractable model to understand these mechanisms in vivo. In Drosophila, GSCs typically divide asymmetrically to produce one stem cell and one differentiating cell. Author summary Germ line association with the somatic cells is critical for various aspects of germ cell biology, including migration, self-renewal and differentiation. These somatic cells create the stem cell niche and regulate the GSC differentiation [13,14,15]. 300234 [PMC free article]. The Drosophila ovarian germline provides a well-studied model of stem cell biology and the mechanisms that regulate their self-renewal and differentiation; from stem cell niche communication and post-transcriptional regulation to systemic signaling and aging. 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). Here, we show that neuropeptide F (NPF) signaling plays an important role in the pathway regulating mating-induced germline stem cell (GSC) proliferation in the fruit fly Drosophila melanogaster. Further, expression in germ cells prior to yolk deposition suggests roles in cyst growth, vitellogenesis, and ecdysone biosynthesis. GSCs are found in both male and female gonads where they maintain egg and sperm production throughout adult life (for detailed description of the. Insulin signaling acts in adult adipocytes via GSK-3β and independently of FOXO to control Drosophila female germline stem cell numbers. This epithelium of follicle cells encases germline cells to create an egg. Complex regulatory interactions with both the niche and the environment modulate germline stem cell. Besides the complex signaling. The Drosophila ovariole tip produces new ovarian follicles on a 12-hour cycle by controlling niche-based germline and follicle stem cell divisions and nurturing their developing daughters. 707-723. Chen D, McKearin DM. The Drosophila male and female germ lines have served as ideal model systems for studying the regulation of stem cell behavior and asymmetric stem cell division controlled by the microenvironment or stem cell niche. Therefore, the non-autonomous ecdysone effect can be explained. The embryonic ovary in Drosophila consists of two primary cell types: the primordial germ cells (PGCs) and the somatic gonadal precursors (SGPs) (Fig. These protocols can be adapted to isolate other cell types from fly ovaries, such as somatic follicle cells or escort cells, by driving GFP expression in the respective target cells. 10. The cell cycle of Drosophila female germline stem cells (GSCs) is characterized by short G 1 and very long G 2 phases, making it an excellent model for the study of cell cycle control in stem cell fate determination. Germline encapsulation requires activated epidermal growth factor. The role of ecdysteroids in stem cell maintenance in the testis has been reported recently. Insulin signaling acts in adult adipocytes via GSK-3β and independently of FOXO to control Drosophila female germline stem cell numbers. These cells include GSCs and cells within the niche itself, including basal terminal filament cells, anterior escort cells, and cap cells (Fig. In the Drosophila germarium (Fig. The stem cell niche is made of 2 to 3 GSCs and supporting cap and. Cai Y. We demonstrated that this nonautonomous effect was mediated by the transcriptional activation of Dpp [the fly homolog of bone morphogenetic protein (BMP)]. 2009; 23: 2742-2752. 5,6 At the tip of the germarium, two or three GSCs contact cap cells anteriorly and inner germarial sheath cells (IGSs) (previously known as escort cells) laterally in region 1 (Fig-ure 1A). The differentiating cell then undergoes exactly four transit-amplifying divisions, yielding 16 interconnected germ cells, before entering meiosis (Figure 1). Stem cell regulation by local signals is intensely studied, but less is known about the effects of hormonal signals on stem cells. Drosophila female germline stem cells (GSCs) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Genetics, 167 (2004), pp. Disruption of Dicer-1 function in GSCs during adult life results in GSC loss. Spatial and. The differentiation programme that produces gametes must be co-ordinated with GSC maintenance and proliferation in order to regulate tissue regeneration. 1 Primordial Germ Cell Migration. 2017; 144. Cap cells, escort cells and terminal filament cells are responsible for producing niche signals that permit the maintenance of GSCs in their. Anatomy of the Germarium and an Overview of Egg Chamber Development. Genes involved in tissue and organ development. In the germarium of the Drosophila ovary, developing germline cysts are surrounded by a population of somatic escort cells that are known to function as the niche cells for germline differentiation; 1 however, the underlying molecular mechanisms of this niche function remain poorly understood. critical growth factor for germ-line stem-cell maintenance and cell division, we added commercially available human BMP4 to M3 (BF. 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). Earlier work demonstrated that Notch ligands produced from GSCs are not required for Notch activation in cap cells ( Hsu and Drummond-Barbosa, 2011 ), suggesting that the required Notch ligands. (A) The Drosophila ovariole/germarium. , 2011; Xie, 2013). Drosophila female germline stem cell (GSC) niche represents a simple and tractable in vivo model with two to three GSCs that can be identified unambiguously by their location next to the cap cells and the presence of spherical spectrosomes ( Figure 1 A). Notably, GSC homeostasis is also known to be. 1 A). (A) Drosophila germarium. The germarium tip contains 2–3 GSCs, identified by their direct contact with cap cells and the presence of ball-shaped spectrosomes stained by Hu-li-tai-shao (Hts); differentiating germline cells maintain Hts expression in branched fusome structures. However,in males there is evidence that the stem cell niche forms during the last. Germline encapsulation requires activated epidermal growth factor receptor (Egfr) signaling within the ECs, following secretion of its ligands from the GCs. In the escort cells (yellow), EcR binds to the co-activator Tai to regulate GSC (dark green) self-renewal. the niches at the tip of the ovariole and testis are larger and house two types of stem cell. The cell cycle of Drosophila female germline stem cells (GSCs) is characterized by short G 1 and very long G 2 phases, making it an excellent model for the study of cell cycle control in stem cell fate determination. Drosophila oogenesis depends on the presence of self-renewing GSCs in the adult ovary 1, 2. The number of stem cells that self-renews and differentiates must be tightly controlled to maintain tissue homeostasis. Transcription of rga pre-mRNA produces both sisR-1 (from the intron) and rga mRNA. Together, these studies suggest that abnormal epigenetic regulation of signaling events at the stem cell niche could lead to stem-cell derived tumorigenesis. In these studies, female-to-male reprogramming was caused by ectopic expression of the. In this article, Hime, Quinn, and colleagues show that the Drosophila Retinoblastoma ortholog, Rbf, is cell autonomously required by somatic cells of the. identify the ECM molecule Perlecan as an essential component of the ovarian niche in Drosophila. 2008; 3:44–54. Moreover, such posterior. A prime example, the germline stem cell (GSC) niche located at the tip of each Drosophila ovariole, maintains 2–3 germline stem cells throughout pupal and adult life (Fig. [Google Scholar] López-Onieva L, Fernández-Miñán A, González-Reyes A. In turn, this activates a protein called Oamb, which is studded through the membrane of cells present around germline stem cells. Drosophila GSCs are currently among the best-understood adult stem cells (1, 2). Self-maintained escort cells form a germline stem cell differentiation niche. The interconnected germ cell cysts then. Experimental model systems have been an invaluable tool for characterising stem cell regulation. 2. mating-induced germline stem cell increase in female Drosophila melanogaster Yuto Yoshinari1, Tomotsune Ameku1†, Shu Kondo2, Hiromu Tanimoto3, Takayuki Kuraishi4,5, Yuko Shimada-Niwa6, Ryusuke. the posterior daughter cell associates with escort cells and becomes a cystoblast (CB). 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). 1 A). The ovary contains at least two stem cell types, germline stem cells (GSCs) and somatic follicular stem cells (FSCs). The female GSC niche is composed of postmitotic somatic cells, including terminal filament cells, four-to-eight cap cells that physically adhere to GSCs, and a subset of escort cells. ExpandThe Drosophila ovaries continually generate mature eggs in adulthood due to a stable population of self-renewable ovarian germline stem cells (GSCs). In the germarium of the Drosophila ovary, developing germline cysts are surrounded by a population of so-matic escort cells that are known to function as the niche cells for germline differentiation;1 however, the un-derlying molecular mechanisms of this niche function remain poorly understood. In the Drosophila ovary, the simultaneous knockdown of Rho1 in germ cells and escort cells causes cell death and lethality, while the specific knockdown of Rho1 in escort cells results in the loss of germ cells. The role of ecdysteroids in stem cell maintenance in the testis has been reported recently. The formula of Drosophila corn medium was 100 g corn flour, brown sugar 40 g, yeast 25 g,. Mounting evidence has demonstrated that BMP-like morphogens are the immediate. 2005), and since Myc expression is high in both D. the escort cells, where it activates transcription of the. In Drosophila ovary, Dpp is secreted from germline stem cell (GSC) niche and activates the BMP signaling in GSCs for their self-renewal. Surprisingly little is known, however, about the mechanisms that pattern this niche, leading to the specification of different niche cell. 43 Additionally, Rho1 works in escort cells to promote GSCs progeny differentiation by maintaining EGFR signalling and preventing. The fruit fly, Drosophila melanogaster, is an excellent genetically tractable model to study the. Knockdown of H1 allows escort cells to acquire the ability similar to the cap cells to produce Dpp, resulting in upregulated BMP activity to decrease Bam expression in spectrosome‐containing germline cells (SCCs). Abstract. Finally, expression of an RNAi against mys in the germarium, in both pre-follicle cells and escort cells, resulted in gross disorganisation of ovarioles, with. , 2004; Wang and Page. We. The ability of adult stem cells to maintain their “stemness” depends critically on the localized microenvironment, or niche. Drosophila exhibits a short lifespan with well-characterized ovarian germline stem cells (GSCs) and niche compartments, providing a good model with which to study stem cell biology. At the apical end of each ovariole lies the germarium, containing the stem cell niche at its anterior tip (figure 1a). Martin et al. Reducing Piwi activity in the testis caused defects in CySC. Establishment and maintenance of stem cells often depends on associated niche cells. Here, we report that in the Drosophila ovarian germline stem cell (GSC) niche, aging-related reductions in expression of Piwi (a transposon silencer) derepress retrotransposons and cause GSC loss. Thanks to comparatively simple morphology and ease of genetic manipulation, the Drosophila ovary and testis have become model tissues for the study of stem cell behavior. Hsu HJ, Drummond-Barbosa D (2011) Insulin signals control the competence of the Drosophila female germline stem cell niche to respond to Notch. , 2020; Zhang and Cai, 2020). Anchoring of the germline stem cells (GSCs) to the maintenance niche is essential for them to preserve a stem cell state (Song and Xie, 2002; Xie and Spradling, 2000), and the encapsulation of the differentiating germline cells (GCs) by escort cells. Keywords: drosophila germline; fluorescence-activated cell sorting (FACS); germline stem cell; isolation. Germ cells, dark pink (GSCs) and light pink. A Cartoon depiction of the beginning stages of Drosophila ovary development showing the cell types, including terminal filament cells (TF, orange) and cap cells (CC, orange), escort cells (EC, green), germline stem cells (GSC, red), a cystoblast (CB, brown), germ cell cysts (yellow), follicle stem cells layers 1–3 (FSCs, layer 1. The germarium consists of germline stem cells, escort stem cells and somatic stem cells,. Expand The Drosophila ovaries continually generate mature eggs in adulthood due to a stable population of self-renewable ovarian germline stem cells (GSCs). Vasa promotes Drosophila germline stem cell differentiation by activating mei-P26 translation by directly interacting. Adult stem cells reside in distinct microenvironments, or niches, that promote their self-renewal and regulate their activity. The Drosophila melanogaster ovarian niche is established by several types of stromal cells, including terminal filament cells, cap cells, and escort cells (ECs). Somatic cells that, together with terminal filament cells and escort cells, make up the germ cell niche in Drosophila melanogaster females. As a highly conserved piRNA pathway component, Piwi is widely expressed in both germ cells and somatic cells in the Drosophila ovary and is required for piRNA production in both cell. Figure S1: c587 GAL4 drives RNAi mediated knock down of USP in somatic escort and follicle cells. Through single-cell gene Results and Discussion. Following a single division, escort stemDrosophila exhibits a short lifespan with well-characterized ovarian germline stem cells (GSCs) and niche compartments, providing a good model with which to study stem cell biology. However,in males there is evidence that the stem cell niche forms during the last stage of. PubMed Abstract. show that germline sexual identity controls how germline stem cells respond to signals in their niche environment. Niche establishment begins in larval stages when terminal filaments (TFs) are formed, but the underlying mechanism for the. 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. A Germline stem cell (GSC) daughters (gray) develop into 16-cell cysts as they progress further posterior (right) in region 1, supported by interactions with quiescent enveloping escort cells (ECs) and span the width of the germarium in region 2b as ECs are replaced by follicle cells (FCs). Leatherman JL, Dinardo S. (E) Smo immunostaining labels somatic cells of the. Improper packaging of the germline can. The Drosophila germarium can undergo development in vitro. (C) Oogenesis begins in the germarium, where germ. The. 2014; 28:459–473.