1
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Gonçalves Antunes M, Sanial M, Contremoulins V, Carvalho S, Plessis A, Becam I. High hedgehog signaling is transduced by a multikinase-dependent switch controlling the apico-basal distribution of the GPCR smoothened. eLife 2022; 11:79843. [PMID: 36083801 PMCID: PMC9462849 DOI: 10.7554/elife.79843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
The oncogenic G-protein-coupled receptor (GPCR) Smoothened (SMO) is a key transducer of the hedgehog (HH) morphogen, which plays an essential role in the patterning of epithelial structures. Here, we examine how HH controls SMO subcellular localization and activity in a polarized epithelium using the Drosophila wing imaginal disc as a model. We provide evidence that HH promotes the stabilization of SMO by switching its fate after endocytosis toward recycling. This effect involves the sequential and additive action of protein kinase A, casein kinase I, and the Fused (FU) kinase. Moreover, in the presence of very high levels of HH, the second effect of FU leads to the local enrichment of SMO in the most basal domain of the cell membrane. Together, these results link the morphogenetic effects of HH to the apico-basal distribution of SMO and provide a novel mechanism for the regulation of a GPCR.
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Affiliation(s)
| | | | | | | | - Anne Plessis
- Université Paris Cité, CNRS, Institut Jacques Monod
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2
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Roberto N, Becam I, Plessis A, Holmgren RA. Engrailed, Suppressor of fused and Roadkill modulate the Drosophila GLI transcription factor Cubitus interruptus at multiple levels. Development 2022; 149:dev200159. [PMID: 35290435 PMCID: PMC10656455 DOI: 10.1242/dev.200159] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 02/03/2022] [Indexed: 12/24/2022]
Abstract
Morphogen gradients need to be robust, but may also need to be tailored for specific tissues. Often this type of regulation is carried out by negative regulators and negative feedback loops. In the Hedgehog (Hh) pathway, activation of patched (ptc) in response to Hh is part of a negative feedback loop limiting the range of the Hh morphogen. Here, we show that in the Drosophila wing imaginal disc two other known Hh targets genes feed back to modulate Hh signaling. First, anterior expression of the transcriptional repressor Engrailed modifies the Hh gradient by attenuating the expression of the Hh pathway transcription factor cubitus interruptus (ci), leading to lower levels of ptc expression. Second, the E-3 ligase Roadkill shifts the competition between the full-length activator and truncated repressor forms of Ci by preferentially targeting full-length Ci for degradation. Finally, we provide evidence that Suppressor of fused, a negative regulator of Hh signaling, has an unexpected positive role, specifically protecting full-length Ci but not the Ci repressor from Roadkill.
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Affiliation(s)
- Nicole Roberto
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60201, USA
| | - Isabelle Becam
- Université de Paris, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | - Anne Plessis
- Université de Paris, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | - Robert A. Holmgren
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60201, USA
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3
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Liu M, Su Y, Peng J, Zhu AJ. Protein modifications in Hedgehog signaling: Cross talk and feedback regulation confer divergent Hedgehog signaling activity. Bioessays 2021; 43:e2100153. [PMID: 34738654 DOI: 10.1002/bies.202100153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 10/06/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022]
Abstract
The complexity of the Hedgehog (Hh) signaling cascade has increased over the course of evolution; however, it does not suffice to accommodate the dynamic yet robust requirements of differential Hh signaling activity needed for embryonic development and adult homeostatic maintenance. One solution to solve this dilemma is to apply multiple forms of post-translational modifications (PTMs) to the core Hh signaling components, modulating their abundance, localization, and signaling activity. This review summarizes various forms of protein modifications utilized to regulate Hh signaling, with a special emphasis on crosstalk between different forms of PTMs and their feedback regulation by Hh signaling.
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Affiliation(s)
- Min Liu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Ying Su
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Jingyu Peng
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Alan Jian Zhu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
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4
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Little JC, Garcia-Garcia E, Sul A, Kalderon D. Drosophila hedgehog can act as a morphogen in the absence of regulated Ci processing. eLife 2020; 9:61083. [PMID: 33084577 PMCID: PMC7679133 DOI: 10.7554/elife.61083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/20/2020] [Indexed: 12/23/2022] Open
Abstract
Extracellular Hedgehog (Hh) proteins induce transcriptional changes in target cells by inhibiting the proteolytic processing of full-length Drosophila Ci or mammalian Gli proteins to nuclear transcriptional repressors and by activating the full-length Ci or Gli proteins. We used Ci variants expressed at physiological levels to investigate the contributions of these mechanisms to dose-dependent Hh signaling in Drosophila wing imaginal discs. Ci variants that cannot be processed supported a normal pattern of graded target gene activation and the development of adults with normal wing morphology, when supplemented by constitutive Ci repressor, showing that Hh can signal normally in the absence of regulated processing. The processing-resistant Ci variants were also significantly activated in the absence of Hh by elimination of Cos2, likely acting through binding the CORD domain of Ci, or PKA, revealing separate inhibitory roles of these two components in addition to their well-established roles in promoting Ci processing. Morphogens play a crucial role in determining how cells are organized in developing organisms. These chemical signals act over a wide area, and the amount of signal each cell receives typically initiates a sequence of events that spatially pattern the multiple cells of an organ or tissue. One of the most well-studied groups of morphogens are the hedgehog proteins, which are involved in the development of many animals, ranging from flies to humans. In fruit flies, hedgehog proteins kickstart a cascade of molecular changes that switch on a set of 'target' genes. They do this by ultimately altering the activity of a protein called cubitus interruptus, which comes in two lengths: a long version called Ci-155 and a short version called Ci-75. When hedgehog is absent, Ci-155 is kept in an inactive state in the cytoplasm, where it is slowly converted into its shorter form, Ci-75: this repressor protein is then able to access the nucleus, where it switches ‘off’ the target genes. However, when a hedgehog signal is present, the processing of Ci into its shorter form is inhibited. Instead, Ci-155 becomes activated by a separate mechanism that allows the long form protein to enter the nucleus and switch ‘on’ the target genes. But it was unclear whether hedgehog requires both of these mechanisms in order to act as a morphogen and regulate the activity of developmental genes. To answer this question, Little et al. mutated the gene for Ci in the embryo of fruit flies, so that the Ci-155 protein could no longer be processed into Ci-75. Examining the developing wings of these flies revealed that the genes targeted by hedgehog are still activated in the correct pattern. In some parts of the wing, Ci-75 is required to switch off specific sets of genes. But when Little et al. blocked these genes, by adding a gene that constantly produces the Ci repressor in the presence or absence of hedgehog, the adult flies still developed normally structured wings. This suggests that hedgehog does not need to regulate the processing of Ci-155 into Ci-75 in order to perform its developmental role. Previous work showed that when one of the major mechanisms used by hedgehog to activate Ci-155 is blocked, fruit flies are still able to develop normal wings. Taken together with the findings of Little et al., this suggests that the two mechanisms induced by hedgehog can compensate for each other, and independently regulate the development of the fruit fly wing. These mechanisms, which are also found in humans, have been linked to birth defects and several common types of cancer, and understanding how they work could help the development of new treatments.
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Affiliation(s)
- Jamie C Little
- Department of Biological Sciences, Columbia University, New York, United States
| | - Elisa Garcia-Garcia
- Department of Biological Sciences, Columbia University, New York, United States
| | - Amanda Sul
- Department of Biological Sciences, Columbia University, New York, United States
| | - Daniel Kalderon
- Department of Biological Sciences, Columbia University, New York, United States
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5
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Bruzzone L, Argüelles C, Sanial M, Miled S, Alvisi G, Gonçalves-Antunes M, Qasrawi F, Holmgren RA, Smibert CA, Lipshitz HD, Boccaccio GL, Plessis A, Bécam I. Regulation of the RNA-binding protein Smaug by the GPCR Smoothened via the kinase Fused. EMBO Rep 2020; 21:e48425. [PMID: 32383557 DOI: 10.15252/embr.201948425] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 03/17/2020] [Accepted: 04/14/2020] [Indexed: 12/13/2022] Open
Abstract
From fly to mammals, the Smaug/Samd4 family of prion-like RNA-binding proteins control gene expression by destabilizing and/or repressing the translation of numerous target transcripts. However, the regulation of its activity remains poorly understood. We show that Smaug's protein levels and mRNA repressive activity are downregulated by Hedgehog signaling in tissue culture cells. These effects rely on the interaction of Smaug with the G-protein coupled receptor Smoothened, which promotes the phosphorylation of Smaug by recruiting the kinase Fused. The activation of Fused and its binding to Smaug are sufficient to suppress its ability to form cytosolic bodies and to antagonize its negative effects on endogenous targets. Importantly, we demonstrate in vivo that HH reduces the levels of smaug mRNA and increases the level of several mRNAs downregulated by Smaug. Finally, we show that Smaug acts as a positive regulator of Hedgehog signaling during wing morphogenesis. These data constitute the first evidence for a post-translational regulation of Smaug and reveal that the fate of several mRNAs bound to Smaug is modulated by a major signaling pathway.
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Affiliation(s)
- Lucia Bruzzone
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Matthieu Sanial
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Samia Miled
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Giorgia Alvisi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Fairouz Qasrawi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Robert A Holmgren
- Department of Mol. Biosci., Northwestern University, Evanston, IL, USA
| | - Craig A Smibert
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Graciela L Boccaccio
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Anne Plessis
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Isabelle Bécam
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
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6
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Yang C, Zheng X, Ye K, Sun Y, Lu Y, Fan Q, Ge H. miR-135a Inhibits the Invasion and Migration of Esophageal Cancer Stem Cells through the Hedgehog Signaling Pathway by Targeting Smo. MOLECULAR THERAPY-NUCLEIC ACIDS 2019; 19:841-852. [PMID: 31981861 PMCID: PMC6976902 DOI: 10.1016/j.omtn.2019.10.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 07/22/2019] [Accepted: 10/27/2019] [Indexed: 02/08/2023]
Abstract
Cancer stem cells (CSCs) have been reported to be involved in esophageal cancer (EC) development. Hence, we aim to explore whether microRNA-135a (miR-135a) affects EC and its associated mechanism. Cancerous and adjacent tissues from 138 EC patients were collected. The dual-luciferase reporter gene assay and bioinformatics analysis were used to confirm the interaction between nucleotides. A series of mimics or inhibitors of miR-135a or small interfering RNA (siRNA) against Smo were introduced into EC cells. After that, the expression of miR-135a and Hedgehog (Hh) signaling pathway-related genes (Smo, Gli1, Shh, and Gli2) in tissues and cells was measured, accompanied by evaluation of cell viability, apoptosis, invasion, and migration. High expression of Smo, Gli1, Shh, and Gli2 and low expression of miR-135a were observed in EC. Smo was verified to be a target gene of miR-135a. In addition, overexpression of miR-135a or silencing of Smo decreased the expression of Gli1, Gli2, and Shh, thus inhibiting EC cell proliferation, migration, and invasion and promoting apoptosis. Silencing of miR-135a was observed to reverse the inhibitory role of miR-135a in EC. These results suggest that miR-135a inhibited the migration and invasion of EC cells through inhibition of the Smo/Hh axis.
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Affiliation(s)
- Chengliang Yang
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China; Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, P.R. China
| | - Xiaoli Zheng
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China
| | - Ke Ye
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China
| | - Yanan Sun
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China
| | - Yufei Lu
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China
| | - Qingxia Fan
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, P.R. China.
| | - Hong Ge
- Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, P.R. China.
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7
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Vijayakumar J, Perrois C, Heim M, Bousset L, Alberti S, Besse F. The prion-like domain of Drosophila Imp promotes axonal transport of RNP granules in vivo. Nat Commun 2019; 10:2593. [PMID: 31197139 PMCID: PMC6565635 DOI: 10.1038/s41467-019-10554-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 05/15/2019] [Indexed: 01/29/2023] Open
Abstract
Prion-like domains (PLDs), defined by their low sequence complexity and intrinsic disorder, are present in hundreds of human proteins. Although gain-of-function mutations in the PLDs of neuronal RNA-binding proteins have been linked to neurodegenerative disease progression, the physiological role of PLDs and their range of molecular functions are still largely unknown. Here, we show that the PLD of Drosophila Imp, a conserved component of neuronal ribonucleoprotein (RNP) granules, is essential for the developmentally-controlled localization of Imp RNP granules to axons and regulates in vivo axonal remodeling. Furthermore, we demonstrate that Imp PLD restricts, rather than promotes, granule assembly, revealing a novel modulatory function for PLDs in RNP granule homeostasis. Swapping the position of Imp PLD compromises RNP granule dynamic assembly but not transport, suggesting that these two functions are uncoupled. Together, our study uncovers a physiological function for PLDs in the spatio-temporal control of neuronal RNP assemblies. The physiological role of prion-like domains (PLDs) within RNA-binding proteins is not well understood. Here, authors show in Drosophila that the PLD in the protein Imp is required for localization of ribonucleoprotein granules to axons and axonal remodelling.
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Affiliation(s)
| | | | - Marjorie Heim
- University Côte d'Azur, CNRS, Inserm, iBV, Nice, 06100, France
| | - Luc Bousset
- Paris-Saclay Institute of Neuroscience, Orsay, 91505, France
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, 01307, Germany.,Center for Molecular and Cellular Bioengineering (CMCB), Biotechnology Center, Technische Universität Dresden, Dresden, 01307, Germany
| | - Florence Besse
- University Côte d'Azur, CNRS, Inserm, iBV, Nice, 06100, France.
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8
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Zhang X, Feng L, Qiao N, Liu Y, Zhang DC, Yin H. Cloning, expression pattern and functional characterization of fused, an important kinase of the Hedgehog signalling pathway from Locusta migratoria(Orthoptera: Acridoidea). BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2019.1637781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
- Xiaohong Zhang
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
| | - Li Feng
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
| | - Ning Qiao
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
| | - Yachao Liu
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
| | - Dao Chuan Zhang
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
| | - Hong Yin
- College of Life Sciences and the Key Laboratory of Zoological Systematics and Application, Hebei University, Baoding, Hebei, P. R. China
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9
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Giordano C, Ruel L, Poux C, Therond P. Protein association changes in the Hedgehog signaling complex mediate differential signaling strength. Development 2018; 145:145/24/dev166850. [PMID: 30541874 DOI: 10.1242/dev.166850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 11/07/2018] [Indexed: 01/20/2023]
Abstract
Hedgehog (Hh) is a conserved morphogen that controls cell differentiation and tissue patterning in metazoans. In Drosophila, the Hh signal is transduced from the G protein-coupled receptor Smoothened (Smo) to the cytoplasmic Hh signaling complex (HSC). How activated Smo is translated into a graded activation of the downstream pathway is still not well understood. In this study, we show that the last amino acids of the cytoplasmic tail of Smo, in combination with G protein-coupled receptor kinase 2 (Gprk2), bind to the regulatory domain of Fused (Fu) and highly activate its kinase activity. We further show that this binding induces changes in the association of Fu protein with the HSC and increases the proximity of the Fu catalytic domain to its substrate, the Costal2 kinesin. We propose a new model in which, depending on the magnitude of Hh signaling, Smo and Gprk2 modulate protein association and conformational changes in the HSC, which are responsible for the differential activation of the pathway.
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Affiliation(s)
- Cecile Giordano
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
| | - Laurent Ruel
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
| | - Candice Poux
- Stockholms Universitet, Wenner-Grens Institut, SE-106 91 Stockholm, Sweden
| | - Pascal Therond
- Université Côte d'Azur, CNRS, Inserm, iBV, 06108 Nice, France
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10
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Praktiknjo SD, Saad F, Maier D, Ip P, Hipfner DR. Activation of Smoothened in the Hedgehog pathway unexpectedly increases Gα s-dependent cAMP levels in Drosophila. J Biol Chem 2018; 293:13496-13508. [PMID: 30018136 DOI: 10.1074/jbc.ra118.001953] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 07/13/2018] [Indexed: 12/28/2022] Open
Abstract
Hedgehog (Hh) signaling plays a key role in the development and maintenance of animal tissues. This signaling is mediated by the atypical G protein-coupled receptor (GPCR) Smoothened (Smo). Smo activation leads to signaling through several well-characterized effectors to activate Hh target gene expression. Recent studies have implicated activation of the heterotrimeric G protein subunit Gαi and the subsequent decrease in cellular cAMP levels in promoting the Hh response in flies and mammals. Although Hh stimulation decreases cAMP levels in some insect cell lines, here using a bioluminescence resonance energy transfer (BRET)-based assay we found that this stimulation had no detectable effect in Drosophila S2-R+ cells. However, we observed an unexpected and significant Gαs-dependent increase in cAMP levels in response to strong Smo activation in Smo-transfected cells. This effect was mediated by Smo's broadly conserved core, and was specifically activated in response to phosphorylation of the Smo C-terminus by GPCR kinase 2 (Gprk2). Genetic analysis of heterotrimeric G protein function in the developing Drosophila wing revealed a positive role for cAMP in the endogenous Hh response. Specifically, we found that mutation or depletion of Gαs diminished low-threshold Hh responses in Drosophila, whereas depletion of Gαi potentiated them (in contrast to previous findings). Our analysis suggested that regulated cAMP production is important for controlling the sensitivity of cellular responses to Hh in Drosophila.
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Affiliation(s)
- Samantha D Praktiknjo
- From the Institut de recherches cliniques de Montréal, Montreal, Quebec H2W 1R7.,the Departments of Anatomy and Cell Biology and
| | - Farah Saad
- From the Institut de recherches cliniques de Montréal, Montreal, Quebec H2W 1R7.,Biology, McGill University, Montreal, Quebec H3A 0C7, and
| | - Dominic Maier
- From the Institut de recherches cliniques de Montréal, Montreal, Quebec H2W 1R7.,the Departments of Anatomy and Cell Biology and
| | - Pamela Ip
- From the Institut de recherches cliniques de Montréal, Montreal, Quebec H2W 1R7.,the Departments of Anatomy and Cell Biology and
| | - David R Hipfner
- From the Institut de recherches cliniques de Montréal, Montreal, Quebec H2W 1R7, .,the Departments of Anatomy and Cell Biology and.,Biology, McGill University, Montreal, Quebec H3A 0C7, and.,the Département de médecine, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
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