Drosophila non-gonadal PIWI protein Aubergine regulates regenerative stem cell proliferation and tumourigenesis in the adult intestine
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ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE253625 | GEO | 2024/12/29
REPOSITORIES: GEO
Similar Datasets
Project description:Somatic stem cells are executors of physiological and pathological proliferation of adult self-renewing tissues, such as the intestine. The actions of intestinal stem cells (ISCs) rely on the integration of cell intrinsic and niche-derived signals, which are necessary to achieve a balanced response to the multiple stimuli that constantly challenge tissue homeostasis and organismal health. Disruption of such balance is causative of age-associated tissue dysfunction and hyperproliferative conditions, including inflammation and cancer. The highly conserved PIWI-interacting RNAs (piRNAs) biosynthesis pathway, also known as the PIWI pathway, has been classically studied in the Drosophila germline for its role in the repression of transposable elements (TEs) and the regulation of germline stem cell homeostasis. Recent reports have emerged on a role of Piwi, the founding member of the pathway, in the maintenance of ISC homeostasis in the adult Drosophila midgut. The implications of these findings regarding a general role of the PIWI pathway and piRNAs in the intestine remain to be addressed. Here, we characterise a cell autonomous role of the PIWI family protein Aubergine (Aub) in ISCs. We show that, while dispensable for homeostatic self-renewal of the midgut, inducible Aub is essential to regulate ISC proliferation following acute damage of the intestinal epithelium and in oncogenic settings. Our work suggests that the role of Aub in ISCs is independent of its piRNAs regulatory function. Instead, Aub drives ISC proliferation through the induction of regenerative stem cell factors Myc and Sox21a, and through the initiation of protein translation by the eukaryotic initiation factor 3 complex (eIF3). In summary, our results discover a role of Aub in damage induced proliferation of the adult Drosophila intestine involving the regulation of major regenerative signalling pathways and the protein translation machinery. Furthermore, we present genetically distinct hyperplastic settings fostering a role of Aub as an intestinal tumour promoter or suppressor.
2024-12-29 | GSE253624 | GEO
Project description:Somatic stem cells are executors of physiological and pathological proliferation of adult self-renewing tissues, such as the intestine. The actions of intestinal stem cells (ISCs) rely on the integration of cell intrinsic and niche-derived signals, which are necessary to achieve a balanced response to the multiple stimuli that constantly challenge tissue homeostasis and organismal health. Disruption of such balance is causative of age-associated tissue dysfunction and hyperproliferative conditions, including inflammation and cancer. The highly conserved PIWI-interacting RNAs (piRNAs) biosynthesis pathway, also known as the PIWI pathway, has been classically studied in the Drosophila germline for its role in the repression of transposable elements (TEs) and the regulation of germline stem cell homeostasis. Recent reports have emerged on a role of Piwi, the founding member of the pathway, in the maintenance of ISC homeostasis in the adult Drosophila midgut. The implications of these findings regarding a general role of the PIWI pathway and piRNAs in the intestine remain to be addressed. Here, we characterise a cell autonomous role of the PIWI family protein Aubergine (Aub) in ISCs. We show that, while dispensable for homeostatic self-renewal of the midgut, inducible Aub is essential to regulate ISC proliferation following acute damage of the intestinal epithelium and in oncogenic settings. Our work suggests that the role of Aub in ISCs is independent of its piRNAs regulatory function. Instead, Aub drives ISC proliferation through the induction of regenerative stem cell factors Myc and Sox21a, and through the initiation of protein translation by the eukaryotic initiation factor 3 complex (eIF3). In summary, our results discover a role of Aub in damage induced proliferation of the adult Drosophila intestine involving the regulation of major regenerative signalling pathways and the protein translation machinery. Furthermore, we present genetically distinct hyperplastic settings fostering a role of Aub as an intestinal tumour promoter or suppressor.
2024-12-29 | GSE253621 | GEO
Project description:Drosophila non-gonadal PIWI protein Aubergine regulates regenerative stem cell proliferation and tumourigenesis in the adult intestine
| PRJNA1066364 | ENA
Project description:Drosophila non-gonadal PIWI protein Aubergine regulates regenerative stem cell proliferation and tumourigenesis in the adult intestine [ncRNA-seq]
| PRJNA1066367 | ENA
Project description:Drosophila non-gonadal PIWI protein Aubergine regulates regenerative stem cell proliferation and tumourigenesis in the adult intestine [RNA-seq]
| PRJNA1066368 | ENA
Project description:Stem cells are essential for the development and long-term maintenance of tissues and organisms. Preserving tissue homeostasis requires exquisite control of all aspects of stem cell function: cell potency, proliferation, fate decision and differentiation. RNA binding proteins (RBPs) are essential components of the regulatory network that control gene expression in stem cells to maintain self-renewal and long-term homeostasis in adult tissues. While the function of many RBPs may have been characterized in various stem cell populations, how these interact and are organized in genetic networks remains largely elusive. In this report, we show that the conserved RNA binding protein IGF2 mRNA binding protein (Imp) is expressed in intestinal stem cells (ISCs) and progenitors in the adult Drosophila midgut. We demonstrate that Imp is required cell autonomously to maintain stem cell proliferative activity under normal epithelial turnover and in response to tissue damage. Mechanistically, we show that Imp cooperates and directly interacts with Lin28, another highly conserved RBP, to regulate ISC proliferation. We found that both proteins bind to and control the InR mRNA, a critical regulator of ISC self-renewal. Altogether, our data suggests that Imp and Lin28 are part of a larger gene regulatory network controlling gene expression in ISCs and required to maintain epithelial homeostasis.
| S-EPMC9484684 | biostudies-literature
Project description:Piwi-interacting RNAs (piRNAs) and PIWI proteins are essential in germ cells to repress transposons and regulate mRNAs. In Drosophila, piRNAs bound to the PIWI protein Aubergine (Aub) are transferred maternally to the embryo and regulate maternal mRNA stability through two opposite roles. They target mRNAs by incomplete base pairing, leading to their destabilization in the soma and stabilization in the germ plasm. Here, we report a function of Aub in translation. Aub is required for translational activation of nanos mRNA, a key determinant of the germ plasm. Aub physically interacts with the poly(A)-binding protein (PABP) and the translation initiation factor eIF3. Polysome gradient profiling reveals the role of Aub at the initiation step of translation. In the germ plasm, PABP and eIF3d assemble in foci that surround Aub-containing germ granules, and Aub acts with eIF3d to promote nanos translation. These results identify translational activation as a new mode of mRNA regulation by Aub, highlighting the versatility of PIWI proteins in mRNA regulation.
| S-EPMC7196074 | biostudies-literature
Project description:Genetic studies of Drosophila melanogaster have provided a paradigm for RNA interference (RNAi) in arthropods, in which the microRNA and antiviral pathways are each mediated by a single Argonaute (Ago1 and Ago2) and germline suppression of transposable elements is mediated by a trio of Piwi-subfamily Argonaute proteins (Ago3, Aub, and Piwi). Without a suitable evolutionary context, deviations from this can be interpreted as derived or idiosyncratic. Here we analyze the evolution of Argonaute genes across the genomes and transcriptomes of 86 Dipteran species, showing that variation in copy number can occur rapidly, and that there is constant flux in some RNAi mechanisms. The lability of the RNAi pathways is illustrated by the divergence of Aub and Piwi (182-156 Ma), independent origins of multiple Piwi-family genes in Aedes mosquitoes (less than 25Ma), and the recent duplications of Ago2 and Ago3 in the tsetse fly Glossina morsitans. In each case the tissue specificity of these genes has altered, suggesting functional divergence or innovation, and consistent with the action of dynamic selection pressures across the Argonaute gene family. We find there are large differences in evolutionary rates and gene turnover between pathways, and that paralogs of Ago2, Ago3, and Piwi/Aub show contrasting rates of evolution after duplication. This suggests that Argonautes undergo frequent evolutionary expansions that facilitate functional divergence.
| S-EPMC4824172 | biostudies-literature
Project description:The production of offspring is energetically costly and relies on incompletely understood mechanisms that generate a positive energy balance. In mothers of many species, changes in key energy-associated internal organs are common yet poorly characterised functionally and mechanistically. In this study, we show that, in adult Drosophila females, the midgut is dramatically remodelled to enhance reproductive output. In contrast to extant models, organ remodelling does not occur in response to increased nutrient intake and/or offspring demands, but rather precedes them. With spatially and temporally directed manipulations, we identify juvenile hormone (JH) as an anticipatory endocrine signal released after mating. Acting through intestinal bHLH-PAS domain proteins Methoprene-tolerant (Met) and Germ cell-expressed (Gce), JH signals directly to intestinal progenitors to yield a larger organ, and adjusts gene expression and sterol regulatory element-binding protein (SREBP) activity in enterocytes to support increased lipid metabolism. Our findings identify a metabolically significant paradigm of adult somatic organ remodelling linking hormonal signals, epithelial plasticity, and reproductive output.
| S-EPMC4515472 | biostudies-literature
Project description:Heterochromatin is made of repetitive sequences, mainly transposable elements (TEs), the regulation of which is critical for genome stability. We have analyzed the role of the heterochromatin-associated Su(var)3-7 protein in Drosophila ovaries. We present evidences that Su(var)3-7 is required for correct oogenesis and female fertility. It accumulates in heterochromatic domains of ovarian germline and somatic cells nuclei, where it co-localizes with HP1. Homozygous mutant females display ovaries with frequent degenerating egg-chambers. Absence of Su(var)3-7 in embryos leads to defects in meiosis and first mitotic divisions due to chromatin fragmentation or chromosome loss, showing that Su(var)3-7 is required for genome integrity. Females homozygous for Su(var)3-7 mutations strongly impair repression of P-transposable element induced gonadal dysgenesis but have minor effects on other TEs. Su(var)3-7 mutations reduce piRNA cluster transcription and slightly impact ovarian piRNA production. However, this modest piRNA reduction does not correlate with transposon de-silencing, suggesting that the moderate effect of Su(var)3-7 on some TE repression is not linked to piRNA production. Strikingly, Su(var)3-7 genetically interacts with the piwi and aubergine genes, key components of the piRNA pathway, by strongly impacting female fertility without impairing transposon silencing. These results lead us to propose that the interaction between Su(var)3-7 and piwi or aubergine controls important developmental processes independently of transposon silencing.
| S-EPMC4018442 | biostudies-literature