The Experts below are selected from a list of 85041 Experts worldwide ranked by ideXlab platform
Heinrich Jasper - One of the best experts on this subject based on the ideXlab platform.
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AWD regulates timed activation of BMP signaling in intestinal stem cells to maintain Tissue Homeostasis
Nature Communications, 2019Co-Authors: Xiaoyu Tracy Cai, Abu Safyan, Jennifer Gawlik, George Pyrowolakis, Hongjie Li, Heinrich JasperAbstract:Precise control of stem cell (SC) proliferation ensures Tissue Homeostasis. In the Drosophila intestine, injury-induced regeneration involves initial activation of intestinal SC (ISC) proliferation and subsequent return to quiescence. These two phases of the regenerative response are controlled by differential availability of the BMP type I receptor Thickveins (Tkv), yet how its expression is dynamically regulated remains unclear. Here we show that during Homeostasis, the E3 ubiquitin ligase Highwire and the ubiquitin-proteasome system maintain low Tkv protein expression. After ISC activation, Tkv is stabilized by proteasome inhibition and undergoes endocytosis due to the induction of the nucleoside diphosphate kinase Abnormal Wing Disc (AWD). Tkv internalization is required for the activation of the Smad protein Mad, and for the return to quiescence after a regenerative episode. Our data provide insight into the mechanisms ensuring Tissue Homeostasis by dynamic control of somatic stem cell activity.Regeneration after injury in the Drosophila intestine involves early activation of intestinal stem cells (ISCs) and subsequent return to quiescence. Here the authors show that return to quiescence by ISCs involves BMP Type I receptor Tkv protein stabilization along with AWD mediated internalization into endocytic vesicles.
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AWD regulates timed activation of BMP signaling in intestinal stem cells to maintain Tissue Homeostasis.
Nature communications, 2019Co-Authors: Xiaoyu Tracy Cai, Abu Safyan, Jennifer Gawlik, George Pyrowolakis, Heinrich JasperAbstract:Precise control of stem cell (SC) proliferation ensures Tissue Homeostasis. In the Drosophila intestine, injury-induced regeneration involves initial activation of intestinal SC (ISC) proliferation and subsequent return to quiescence. These two phases of the regenerative response are controlled by differential availability of the BMP type I receptor Thickveins (Tkv), yet how its expression is dynamically regulated remains unclear. Here we show that during Homeostasis, the E3 ubiquitin ligase Highwire and the ubiquitin-proteasome system maintain low Tkv protein expression. After ISC activation, Tkv is stabilized by proteasome inhibition and undergoes endocytosis due to the induction of the nucleoside diphosphate kinase Abnormal Wing Disc (AWD). Tkv internalization is required for the activation of the Smad protein Mad, and for the return to quiescence after a regenerative episode. Our data provide insight into the mechanisms ensuring Tissue Homeostasis by dynamic control of somatic stem cell activity.
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maintaining Tissue Homeostasis dynamic control of somatic stem cell activity
Cell Stem Cell, 2011Co-Authors: Benoit Biteau, Christine E Hochmuth, Heinrich JasperAbstract:Long-term maintenance of Tissue Homeostasis relies on the accurate regulation of somatic stem cell activity. Somatic stem cells have to respond to Tissue damage and proliferate according to Tissue requirements while avoiding overproliferation. The regulatory mechanisms involved in these responses are now being unraveled in the intestinal epithelium of Drosophila , providing new insight into strategies and mechanisms of stem cell regulation in barrier epithelia. Here, we review these studies and highlight recent findings in vertebrate epithelia that indicate significant conservation of regenerative strategies between vertebrate and fly epithelia.
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JNK Activity in Somatic Stem Cells Causes Loss of Tissue Homeostasis in the Aging Drosophila Gut
Cell stem cell, 2008Co-Authors: Benoit Biteau, Christine E Hochmuth, Heinrich JasperAbstract:Metazoans employ cytoprotective and regenerative strategies to maintain Tissue Homeostasis. Understanding the coordination of these strategies is critical to developing accurate models for aging and associated diseases. Here we show that cytoprotective Jun N-terminal kinase (JNK) signaling influences regeneration in the Drosophila gut by directing proliferation of intestinal stem cells (ISCs). Interestingly, this function of JNK contributes to the loss of Tissue Homeostasis in old and stressed intestines by promoting the accumulation of misdifferentiated ISC daughter cells. Ectopic Delta/Notch signaling in these cells causes their abnormal differentiation but also limits JNK-induced proliferation. Protective JNK signaling and control of cell proliferation and differentiation by Delta/Notch signaling thus have to be carefully balanced to ensure Tissue Homeostasis. Our findings suggest that this balance is lost in old animals, increasing the potential for neoplastic transformation.
Yukiko M. Yamashita - One of the best experts on this subject based on the ideXlab platform.
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The regulated elimination of transit-amplifying cells preserves Tissue Homeostasis during protein starvation in Drosophila testis
Development, 2015Co-Authors: Heiko Yang, Yukiko M. YamashitaAbstract:How Tissues adapt to varying nutrient conditions is of fundamental importance for robust Tissue Homeostasis throughout the life of an organism, but the underlying mechanisms are poorly understood. Here, we show that Drosophila testis responds to protein starvation by eliminating transit-amplifying spermatogonia (SG) while maintaining a reduced pool of actively proliferating germline stem cells (GSCs). During protein starvation, SG die in a manner that is mediated by the apoptosis of somatic cyst cells (CCs) that encapsulate SG and regulate their development. Strikingly, GSCs cannot be maintained during protein starvation when CC-mediated SG death is inhibited, leading to an irreversible collapse of Tissue Homeostasis. We propose that the regulated elimination of transit-amplifying cells is essential to preserve stem cell function and Tissue Homeostasis during protein starvation.
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Polarity in Stem Cell Division: Asymmetric Stem Cell Division in Tissue Homeostasis
Cold Spring Harbor perspectives in biology, 2009Co-Authors: Yukiko M. Yamashita, Hebao Yuan, Jun Cheng, Alan J. HuntAbstract:Many adult stem cells divide asymmetrically to balance self-renewal and differentiation, thereby maintaining Tissue Homeostasis. Asymmetric stem cell divisions depend on asymmetric cell architecture (i.e., cell polarity) within the cell and/or the cellular environment. In particular, as residents of the Tissues they sustain, stem cells are inevitably placed in the context of the Tissue architecture. Indeed, many stem cells are polarized within their microenvironment, or the stem cell niche, and their asymmetric division relies on their relationship with the microenvironment. Here, we review asymmetric stem cell divisions in the context of the stem cell niche with a focus on Drosophila germ line stem cells, where the nature of niche-dependent asymmetric stem cell division is well characterized.
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Stem Cells and Stem Cell Niches in Tissue Homeostasis: Lessons from the Expanding Stem Cell Populations of Drosophila
Regulatory Networks in Stem Cells, 2009Co-Authors: Yukiko M. YamashitaAbstract:New stem cell populations and their niches have been discovered continuously in Drosophila, changing the view that the adult Drosophila body consists primarily of post-mitotic organs and is not suited for the study of dynamic Tissue Homeostasis. With a century of genetics history as well as many sophisticated tools for the genetic analysis of cellular and developmental biology, Drosophila has now emerged as an impressive model system in which to study stem cell biology in great detail.
Georg Bohn - One of the best experts on this subject based on the ideXlab platform.
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p14–MP1-MEK1 signaling regulates endosomal traffic and cellular proliferation during Tissue Homeostasis
The Journal of cell biology, 2006Co-Authors: David Teis, Nicole Taub, Robert Kurzbauer, Diana Hilber, Mariana E. G. De Araujo, Miriam Erlacher, Martin Offterdinger, Andreas Villunger, Stephan Geley, Georg BohnAbstract:The extracellular signal-regulated kinase (ERK) cascade regulates proliferation, differentiation, and survival in multicellular organisms. Scaffold proteins regulate intracellular signaling by providing critical spatial and temporal specificity. The scaffold protein MEK1 (mitogen-activated protein kinase and ERK kinase 1) partner (MP1) is localized to late endosomes by the adaptor protein p14. Using conditional gene disruption of p14 in mice, we now demonstrate that the p14–MP1-MEK1 signaling complex regulates late endosomal traffic and cellular proliferation. This function its essential for early embryogenesis and during Tissue Homeostasis, as revealed by epidermis-specific deletion of p14 . These findings show that endosomal p14–MP1-MEK1 signaling has a specific and essential function in vivo and, therefore, indicate that regulation of late endosomal traffic by extracellular signals is required to maintain Tissue Homeostasis.
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p14 mp1 mek1 signaling regulates endosomal traffic and cellular proliferation during Tissue Homeostasis
Journal of Cell Biology, 2006Co-Authors: David Teis, Nicole Taub, Robert Kurzbauer, Diana Hilber, Mariana E. G. De Araujo, Miriam Erlacher, Martin Offterdinger, Andreas Villunger, Stephan Geley, Georg BohnAbstract:The extracellular signal-regulated kinase (ERK) cascade regulates proliferation, differentiation, and survival in multicellular organisms. Scaffold proteins regulate intracellular signaling by providing critical spatial and temporal specificity. The scaffold protein MEK1 (mitogen-activated protein kinase and ERK kinase 1) partner (MP1) is localized to late endosomes by the adaptor protein p14. Using conditional gene disruption of p14 in mice, we now demonstrate that the p14–MP1-MEK1 signaling complex regulates late endosomal traffic and cellular proliferation. This function its essential for early embryogenesis and during Tissue Homeostasis, as revealed by epidermis-specific deletion of p14 . These findings show that endosomal p14–MP1-MEK1 signaling has a specific and essential function in vivo and, therefore, indicate that regulation of late endosomal traffic by extracellular signals is required to maintain Tissue Homeostasis.
Alan J. Hunt - One of the best experts on this subject based on the ideXlab platform.
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Polarity in Stem Cell Division: Asymmetric Stem Cell Division in Tissue Homeostasis
Cold Spring Harbor perspectives in biology, 2009Co-Authors: Yukiko M. Yamashita, Hebao Yuan, Jun Cheng, Alan J. HuntAbstract:Many adult stem cells divide asymmetrically to balance self-renewal and differentiation, thereby maintaining Tissue Homeostasis. Asymmetric stem cell divisions depend on asymmetric cell architecture (i.e., cell polarity) within the cell and/or the cellular environment. In particular, as residents of the Tissues they sustain, stem cells are inevitably placed in the context of the Tissue architecture. Indeed, many stem cells are polarized within their microenvironment, or the stem cell niche, and their asymmetric division relies on their relationship with the microenvironment. Here, we review asymmetric stem cell divisions in the context of the stem cell niche with a focus on Drosophila germ line stem cells, where the nature of niche-dependent asymmetric stem cell division is well characterized.
Shree Ram Singh - One of the best experts on this subject based on the ideXlab platform.
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Stem cell niche in Tissue Homeostasis, aging and cancer.
Current medicinal chemistry, 2012Co-Authors: Shree Ram SinghAbstract:Abstract Stem cells have an essential role in Tissue Homeostasis, repair, and regeneration of a Tissue or an organ. Stem cells are immature cells having unlimited ability of self-renewal and capacity to differentiate into specialized cell types. Proper regulation of these dual properties is critical in animal development, growth control, and reproduction. Accumulating evidences suggest that stem cell behavior is regulated by both extracellular signals from the niche cells and intrinsic signal within stem cells. Using diverse model systems, tremendous work has been done to understand how niche control the stem cell self-renewal and differentiation. This review presents the progress made in stem cell niche field in germline and somatic stem cells in lower organism and mammals. The knowledge gained by studying the stem cells and its niches in diverse model organisms and the molecular mechanisms regulate their behavior are vital in understanding Tissue Homeostasis, regeneration, aging and cancer in humans.
