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Sachan N, Sharma V, Mutsuddi M, Mukherjee A. Notch signalling: multifaceted role in development and disease. FEBS J 2024; 291:3030-3059. [PMID: 37166442 DOI: 10.1111/febs.16815] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 02/08/2023] [Accepted: 05/10/2023] [Indexed: 05/12/2023]
Abstract
Notch pathway is an evolutionarily conserved signalling system that operates to influence an astonishing array of cell fate decisions in different developmental contexts. Notch signalling plays important roles in many developmental processes, making it difficult to name a tissue or a developing organ that does not depend on Notch function at one stage or another. Thus, dysregulation of Notch signalling is associated with many developmental defects and various pathological conditions, including cancer. Although many recent advances have been made to reveal different aspects of the Notch signalling mechanism and its intricate regulation, there are still many unanswered questions related to how the Notch signalling pathway functions in so many developmental events. The same pathway can be deployed in numerous cellular contexts to play varied and critical roles in an organism's development and this is only possible because of the complex regulatory mechanisms of the pathway. In this review, we provide an overview of the mechanism and regulation of the Notch signalling pathway along with its multifaceted functions in different aspects of development and disease.
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Affiliation(s)
- Nalani Sachan
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY, USA
| | - Vartika Sharma
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Mousumi Mutsuddi
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Ashim Mukherjee
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
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2
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Zhang Q, Zhang P, Yang M, Tian Y, Feng C, Wei W. Identifications of three novel alleles of Serrate in Drosophila. Cells Dev 2024; 177:203908. [PMID: 38403117 DOI: 10.1016/j.cdev.2024.203908] [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: 08/01/2023] [Revised: 02/18/2024] [Accepted: 02/22/2024] [Indexed: 02/27/2024]
Abstract
The Notch signaling pathway, an evolutionarily highly conserved pathway, participates in various essential physiological processes in organisms. Activation of Notch signaling in the canonical manner requires the combination of ligand and receptor. There are two ligands of Notch in Drosophila: Delta (Dl) and Serrate (Ser). A mutation mf157 is identified for causing nicks of fly wings in genetic analysis from a mutant library (unpublished) that was established previously. Immunofluorescent staining illustrates that mf157 represses the expression of Cut and Wingless (Wg), the targets of Notch signaling. MARCM cloning analysis reveals that mf157 functions at the same level or the upstream of ligands of Notch in signaling sending cells. Sequencing demonstrates that mf157 is a novel allele of the Ser gene. Subsequently, mf553 and mf167 are also identified as new alleles of Ser from our library. Furthermore, the complementary assays and the examination of transcripts confirm the sequencing results. Besides, the repressed phenotypes of Notch signaling were reverted by transposon excision experiments of mf157. In conclusion, we identify three fresh alleles of Ser. Our works supply additional genetic resources for further study of functions of Ser and Notch signaling regulation.
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Affiliation(s)
- Qinghai Zhang
- Key Laboratory of Medical Insects, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China; Department of Biology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China; Research Center for Basic Sciences of Medicine, Guizhou Medical University, Guiyang 550025, China.
| | - Pei Zhang
- Key Laboratory of Medical Insects, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China; Department of Biology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China
| | - Min Yang
- Department of Biology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China
| | - Yingxue Tian
- Department of Biology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China
| | - Chunxia Feng
- Department of Biology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China
| | - Wei Wei
- Multimedia Laboratory of Morphology, College of Basic Medicine, Guizhou Medical University, Guiyang 550025, China.
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3
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White MJ, Jacobs KA, Singh T, Mayo LN, Lin A, Chen CS, Jun YW, Kutys ML. Notch1 cortical signaling regulates epithelial architecture and cell-cell adhesion. J Cell Biol 2023; 222:e202303013. [PMID: 37796194 PMCID: PMC10555887 DOI: 10.1083/jcb.202303013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 08/03/2023] [Accepted: 09/06/2023] [Indexed: 10/06/2023] Open
Abstract
Notch receptors control tissue morphogenic processes that involve coordinated changes in cell architecture and gene expression, but how a single receptor can produce these diverse biological outputs is unclear. Here, we employ a 3D model of a human ductal epithelium to reveal tissue morphogenic defects result from loss of Notch1, but not Notch1 transcriptional signaling. Instead, defects in duct morphogenesis are driven by dysregulated epithelial cell architecture and mitogenic signaling which result from the loss of a transcription-independent, Notch1 cortical signaling mechanism that ultimately functions to stabilize adherens junctions and cortical actin. We identify that Notch1 localization and cortical signaling are tied to apical-basal cell restructuring and discover that a Notch1-FAM83H interaction underlies control of epithelial adherens junctions and cortical actin. Together, these results offer new insights into Notch1 signaling and regulation and advance a paradigm in which transcriptional and cell adhesive programs might be coordinated by a single receptor.
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Affiliation(s)
- Matthew J. White
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
| | - Kyle A. Jacobs
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, CA, USA
| | - Tania Singh
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
- Joint Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, USA
| | - Lakyn N. Mayo
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
- Joint Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, USA
| | - Annie Lin
- Joint Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, USA
- Department of Otolaryngology, University of California San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
| | - Christopher S. Chen
- Department of Biomedical Engineering, The Biological Design Center, Boston University, Boston, MA, USA
| | - Young-wook Jun
- Joint Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, USA
- Department of Otolaryngology, University of California San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Matthew L. Kutys
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, CA, USA
- Joint Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, USA
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
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4
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Lim DH, Choi MS, Jeon JW, Lee YS. MicroRNA miR-252-5p regulates the Notch signaling pathway by targeting Rab6 in Drosophila wing development. INSECT SCIENCE 2023; 30:1431-1444. [PMID: 36847222 DOI: 10.1111/1744-7917.13188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
The Notch signaling pathway plays a central role in the development of various organisms. However, dysregulation of microRNAs (miRNAs), which are crucial regulators of gene expression, can disrupt signaling pathways at all stages of development. Although Notch signaling is involved in wing development in Drosophila, the mechanism underlying miRNA-based regulation of the Notch signaling pathway is unclear. Here, we report that loss of Drosophila miR-252 increases the size of adult wings, whereas the overexpression of miR-252 in specific compartments of larval wing discs leads to patterning defects in the adult wings. The miR-252 overexpression-induced wing phenotypes were caused by aberrant Notch signaling with intracellular accumulation of the full-length Notch receptor during development, which could be due to defects in intracellular Notch trafficking associated with its recycling to the plasma membrane and autophagy-mediated degradation. Moreover, we identified Rab6 as a direct target of miR-252-5p; Rab6 encodes a small Ras-like GTPase that regulates endosomal trafficking pathways. Consistent with this finding, RNAi-mediated downregulation of Rab6 led to similar defects in both wing patterning and Notch signaling. Notably, co-overexpression of Rab6 completely rescued the wing phenotype associated with miR-252 overexpression, further supporting that Rab6 is a biologically relevant target of miR-252-5p in the context of wing development. Thus, our data indicate that the miR-252-5p-Rab6 regulatory axis is involved in Drosophila wing development by controlling the Notch signaling pathway.
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Affiliation(s)
- Do-Hwan Lim
- School of Systems Biomedical Science, Soongsil University, Seoul, Republic of Korea
| | - Min-Seok Choi
- College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seoul, Republic of Korea
| | - Ji Won Jeon
- School of Systems Biomedical Science, Soongsil University, Seoul, Republic of Korea
| | - Young Sik Lee
- College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
- Institute of Animal Molecular Biotechnology, Korea University, Seoul, Republic of Korea
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5
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Rosales-Vega M, Reséndez-Pérez D, Zurita M, Vázquez M. TnaA, a trithorax group protein, modulates wingless expression in different regions of the Drosophila wing imaginal disc. Sci Rep 2023; 13:15162. [PMID: 37704704 PMCID: PMC10499800 DOI: 10.1038/s41598-023-42169-z] [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: 02/09/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023] Open
Abstract
wingless expression is exquisitely regulated by different factors and enhancers in the imaginal wing discs of Drosophila melanogaster in four domains: the dorsal band, the dorso-ventral boundary, and the inner and outer ring domains. tonalli is a trithorax group gene that encodes a putative SUMO E3 ligase that binds to chromatin to regulate the expression of its targets, including the Hox genes. However, its role in modulating gene expression is barely known. Here, we show that TnaA modulates the wingless expression at two domains of the wing disc, the dorso-ventral boundary and the inner ring. At first, tonalli interacts genetically with Notch to form the wing margin. In the inner ring domain, TnaA modulates wingless transcription. When the dosage of TnaA increases in or near the inner ring since early larval stages, this domain expands with a rapid increase in wingless expression. TnaA occupies the wingless Inner Ring Enhancer at the wing disc, meanwhile it does not affect wingless expression directed by the Ventral Disc Enhancer in leg discs, suggesting that TnaA acts as a wingless enhancer-specific factor. We describe for the first time the presence of TnaA at the Inner Ring Enhancer as a specific regulator of wingless in the development of wing boundaries.
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Affiliation(s)
- Marco Rosales-Vega
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Diana Reséndez-Pérez
- Departamento de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Mario Zurita
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Martha Vázquez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico.
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White MJ, Jacobs KA, Singh T, Kutys ML. Notch1 cortical signaling regulates epithelial architecture and cell-cell adhesion. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.23.524428. [PMID: 36747830 PMCID: PMC9900753 DOI: 10.1101/2023.01.23.524428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Notch receptors control tissue morphogenic processes that involve coordinated changes in cell architecture and gene expression, but how a single receptor can produce these diverse biological outputs is unclear. Here we employ a 3D organotypic model of a ductal epithelium to reveal tissue morphogenic defects result from loss of Notch1, but not Notch1 transcriptional signaling. Instead, defects in duct morphogenesis are driven by dysregulated epithelial cell architecture and mitogenic signaling which result from loss of a transcription-independent Notch1 cortical signaling mechanism that ultimately functions to stabilize adherens junctions and cortical actin. We identify that Notch1 localization and cortical signaling are tied to apical-basal cell restructuring and discover a Notch1-FAM83H interaction underlies stabilization of adherens junctions and cortical actin. Together, these results offer new insights into Notch1 signaling and regulation, and advance a paradigm in which transcriptional and cell adhesive programs might be coordinated by a single receptor.
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Affiliation(s)
- Matthew J. White
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco CA, 94143, USA
| | - Kyle A. Jacobs
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco CA, 94143, USA
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco CA, 94143, USA
| | - Tania Singh
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco CA, 94143, USA
- Joint Graduate Program in Bioengineering, University of California San Francisco, University of California Berkeley, San Francisco CA, 94143, USA
| | - Matthew L. Kutys
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco CA, 94143, USA
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco CA, 94143, USA
- Joint Graduate Program in Bioengineering, University of California San Francisco, University of California Berkeley, San Francisco CA, 94143, USA
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco CA, 94143, USA
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Notch Missense Mutations in Drosophila Reveal Functions of Specific EGF-like Repeats in Notch Folding, Trafficking, and Signaling. Biomolecules 2022; 12:biom12121752. [PMID: 36551180 PMCID: PMC9775759 DOI: 10.3390/biom12121752] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 11/29/2022] Open
Abstract
Notch signaling plays various roles in cell-fate specification through direct cell-cell interactions. Notch receptors are evolutionarily conserved transmembrane proteins with multiple epidermal growth factor (EGF)-like repeats. Drosophila Notch has 36 EGF-like repeats, and while some play a role in Notch signaling, the specific functions of most remain unclear. To investigate the role of each EGF-like repeat, we used 19 previously identified missense mutations of Notch with unique amino acid substitutions in various EGF-like repeats and a transmembrane domain; 17 of these were identified through a single genetic screen. We assessed these mutants' phenotypes in the nervous system and hindgut during embryogenesis, and found that 10 of the 19 Notch mutants had defects in both lateral inhibition and inductive Notch signaling, showing context dependency. Of these 10 mutants, six accumulated Notch in the endoplasmic reticulum (ER), and these six were located in EGF-like repeats 8-10 or 25. Mutations with cysteine substitutions were not always coupled with ER accumulation. This suggests that certain EGF-like repeats may be particularly susceptible to structural perturbation, resulting in a misfolded and inactive Notch product that accumulates in the ER. Thus, we propose that these EGF-like repeats may be integral to Notch folding.
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Gagliani EK, Gutzwiller LM, Kuang Y, Odaka Y, Hoffmeister P, Hauff S, Turkiewicz A, Harding-Theobald E, Dolph PJ, Borggrefe T, Oswald F, Gebelein B, Kovall RA. A Drosophila Su(H) model of Adams-Oliver Syndrome reveals cofactor titration as a mechanism underlying developmental defects. PLoS Genet 2022; 18:e1010335. [PMID: 35951645 PMCID: PMC9398005 DOI: 10.1371/journal.pgen.1010335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 08/23/2022] [Accepted: 07/11/2022] [Indexed: 12/02/2022] Open
Abstract
Notch signaling is a conserved pathway that converts extracellular receptor-ligand interactions into changes in gene expression via a single transcription factor (CBF1/RBPJ in mammals; Su(H) in Drosophila). In humans, RBPJ variants have been linked to Adams-Oliver syndrome (AOS), a rare autosomal dominant disorder characterized by scalp, cranium, and limb defects. Here, we found that a previously described Drosophila Su(H) allele encodes a missense mutation that alters an analogous residue found in an AOS-associated RBPJ variant. Importantly, genetic studies support a model that heterozygous Drosophila with the AOS-like Su(H) allele behave in an opposing manner to heterozygous flies with a Su(H) null allele, due to a dominant activity of sequestering either the Notch co-activator or the antagonistic Hairless co-repressor. Consistent with this model, AOS-like Su(H) and Rbpj variants have decreased DNA binding activity compared to wild type proteins, but these variants do not significantly alter protein binding to the Notch co-activator or the fly and mammalian co-repressors, respectively. Taken together, these data suggest a cofactor sequestration mechanism underlies AOS phenotypes associated with RBPJ variants, whereby the AOS-associated RBPJ allele encodes a protein with compromised DNA binding activity that retains cofactor binding, resulting in Notch target gene dysregulation. Adams-Oliver Syndrome (AOS) is a rare disease defined by missing skin/skull tissue, limb malformations, and cardiovascular abnormalities. Human genetic studies have revealed that ~40% of AOS patients inherit dominant mutations within specific genes in the Notch signaling pathway. Notch signaling is a highly conserved cell-to-cell communication pathway found in all metazoans and plays crucial roles during embryogenesis and tissue homeostasis in organisms from Drosophila (fruit-flies) to mammals. The Notch receptor converts cell-to-cell interactions into a Notch signal that enters the nucleus and activates target genes by binding to a highly conserved transcription factor. Here, we took advantage of the unexpected finding that a previously described dominant allele in the Drosophila Notch pathway transcription factor contains a missense variant in an analogous residue found in a family with AOS. Using this novel animal model of AOS along with biochemical DNA binding, protein-protein interaction, and transcriptional reporter assays, we found that this transcription factor variant selectively compromises DNA binding but not binding to the Notch signal nor binding to other proteins in the Notch pathway. Taken together with prior human genetic studies, these data suggest AOS phenotypes associated with variants in the Notch pathway transcription factor are caused by a dominant mechanism that sequesters the Notch signal, leading to Notch target gene dysregulation.
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Affiliation(s)
- Ellen K. Gagliani
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Lisa M. Gutzwiller
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Yi Kuang
- Graduate program in Molecular and Developmental Biology, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, United States of America
| | - Yoshinobu Odaka
- Biology Department, University of Cincinnati Blue Ash College, Cincinnati, Ohio, United States of America
| | - Phillipp Hoffmeister
- University Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine, Ulm, Germany
| | - Stefanie Hauff
- University Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine, Ulm, Germany
| | | | - Emily Harding-Theobald
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Patrick J. Dolph
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Tilman Borggrefe
- Institute of Biochemistry, University of Giessen, Giessen, Germany
| | - Franz Oswald
- University Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine, Ulm, Germany
| | - Brian Gebelein
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail: (BG); (RAK)
| | - Rhett A. Kovall
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail: (BG); (RAK)
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Farfán-Pira KJ, Martínez-Cuevas TI, Reyes R, Evans TA, Nahmad M. The vestigial Quadrant Enhancer is dispensable for pattern formation and development of the Drosophila wing. MICROPUBLICATION BIOLOGY 2022; 2022:10.17912/micropub.biology.000585. [PMID: 35783575 PMCID: PMC9242444 DOI: 10.17912/micropub.biology.000585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 06/07/2022] [Accepted: 06/09/2022] [Indexed: 11/06/2022]
Abstract
In Drosophila , the pattern of the wing selector gene, vestigial ( vg ), is established by at least two enhancers: the Boundary Enhancer, which drives expression along the disc's Dorsal-Ventral boundary; and the Quadrant Enhancer (QE) that patterns the rest of the wing pouch. Using CRISPR/Cas9 editing, we deleted DNA fragments around the reported QE sequence and found that the full Vg pattern is formed. Furthermore, adult wings arising from these gene-edited animals are normal in shape and pattern, but slightly smaller in size, although this reduction is not wing-specific in males. We suggest that other enhancers act redundantly to establish the vg pattern and rescue wing development.
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Affiliation(s)
- Keity J Farfán-Pira
- Department of Physiology, Biophysics, and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN)
| | - Teresa I Martínez-Cuevas
- Department of Physiology, Biophysics, and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN)
| | - Rosalio Reyes
- Department of Physiology, Biophysics, and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN)
| | | | - Marcos Nahmad
- Department of Physiology, Biophysics, and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN)
,
Correspondence to: Marcos Nahmad (
)
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10
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Pulianmackal AJ, Kanakousaki K, Flegel K, Grushko OG, Gourley E, Rozich E, Buttitta LA. Misregulation of Nucleoporins 98 and 96 leads to defects in protein synthesis that promote hallmarks of tumorigenesis. Dis Model Mech 2022; 15:dmm049234. [PMID: 35107131 PMCID: PMC8938402 DOI: 10.1242/dmm.049234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 01/15/2022] [Indexed: 11/20/2022] Open
Abstract
Nucleoporin 98KD (Nup98) is a promiscuous translocation partner in hematological malignancies. Most disease models of Nup98 translocations involve ectopic expression of the fusion protein under study, leaving the endogenous Nup98 loci unperturbed. Overlooked in these approaches is the loss of one copy of normal Nup98 in addition to the loss of Nup96 - a second Nucleoporin encoded within the same mRNA and reading frame as Nup98 - in translocations. Nup98 and Nup96 are also mutated in a number of other cancers, suggesting that their disruption is not limited to blood cancers. We found that reducing Nup98-96 function in Drosophila melanogaster (in which the Nup98-96 shared mRNA and reading frame is conserved) de-regulates the cell cycle. We found evidence of overproliferation in tissues with reduced Nup98-96, counteracted by elevated apoptosis and aberrant signaling associated with chronic wounding. Reducing Nup98-96 function led to defects in protein synthesis that triggered JNK signaling and contributed to hallmarks of tumorigenesis when apoptosis was inhibited. We suggest that partial loss of Nup98-96 function in translocations could de-regulate protein synthesis, leading to signaling that cooperates with other mutations to promote tumorigenesis.
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Affiliation(s)
| | | | | | | | | | | | - Laura A. Buttitta
- Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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11
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Abstract
The Drosophila wing imaginal disc is a tissue of undifferentiated cells that are precursors of the wing and most of the notum of the adult fly. The wing disc first forms during embryogenesis from a cluster of ∼30 cells located in the second thoracic segment, which invaginate to form a sac-like structure. They undergo extensive proliferation during larval stages to form a mature larval wing disc of ∼35,000 cells. During this time, distinct cell fates are assigned to different regions, and the wing disc develops a complex morphology. Finally, during pupal stages the wing disc undergoes morphogenetic processes and then differentiates to form the adult wing and notum. While the bulk of the wing disc comprises epithelial cells, it also includes neurons and glia, and is associated with tracheal cells and muscle precursor cells. The relative simplicity and accessibility of the wing disc, combined with the wealth of genetic tools available in Drosophila, have combined to make it a premier system for identifying genes and deciphering systems that play crucial roles in animal development. Studies in wing imaginal discs have made key contributions to many areas of biology, including tissue patterning, signal transduction, growth control, regeneration, planar cell polarity, morphogenesis, and tissue mechanics.
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Affiliation(s)
- Bipin Kumar Tripathi
- Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA
| | - Kenneth D Irvine
- Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers University, Piscataway, NJ 08854, USA
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12
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Mo D, Shen J, Zhang J. Use of FLP/FRT System to Screen for Notch Signaling Regulators in the Drosophila Wing. Methods Mol Biol 2022; 2472:39-48. [PMID: 35674890 DOI: 10.1007/978-1-0716-2201-8_4] [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] [Indexed: 06/15/2023]
Abstract
Mutations of genes encoding key components of the Notch signaling pathways often result in lethality at early developmental stages, making it difficult to decipher how they regulate the formation of specific cell types or organs. Mosaic analysis using the FLP/FRT system allows investigating the roles of essential genes during wing development in Drosophila melanogaster. This chapter describes the practical methods to isolate Notch signaling regulators by somatic mosaic screen. The fly stocks, cross schemes, and screen parameters are summarized. We also explain how to validate the roles of potential Notch signaling regulators.
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Affiliation(s)
- Dongqing Mo
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Jie Shen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Junzheng Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China.
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13
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Kandasamy S, Couto K, Thackeray J. A docked mutation phenocopies dumpy oblique alleles via altered vesicle trafficking. PeerJ 2021; 9:e12175. [PMID: 34721959 PMCID: PMC8520396 DOI: 10.7717/peerj.12175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/27/2021] [Indexed: 11/20/2022] Open
Abstract
The Drosophila extracellular matrix protein Dumpy (Dpy) is one of the largest proteins encoded by any animal. One class of dpy mutations produces a characteristic shortening of the wing blade known as oblique (dpyo ), due to altered tension in the developing wing. We describe here the characterization of docked (doc), a gene originally named because of an allele producing a truncated wing. We show that doc corresponds to the gene model CG5484, which encodes a homolog of the yeast protein Yif1 and plays a key role in ER to Golgi vesicle transport. Genetic analysis is consistent with a similar role for Doc in vesicle trafficking: docked alleles interact not only with genes encoding the COPII core proteins sec23 and sec13, but also with the SNARE proteins synaptobrevin and syntaxin. Further, we demonstrate that the strong similarity between the doc1 and dpyo wing phenotypes reflects a functional connection between the two genes; we found that various dpy alleles are sensitive to changes in dosage of genes encoding other vesicle transport components such as sec13 and sar1. Doc's effects on trafficking are not limited to Dpy; for example, reduced doc dosage disturbed Notch pathway signaling during wing blade and vein development. These results suggest a model in which the oblique wing phenotype in doc1 results from reduced transport of wild-type Dumpy protein; by extension, an additional implication is that the dpyo alleles can themselves be explained as hypomorphs.
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Affiliation(s)
- Suresh Kandasamy
- Department of Biology, Clark University, Worcester, Massachusetts, United States
| | - Kiley Couto
- Department of Biology, Clark University, Worcester, Massachusetts, United States
| | - Justin Thackeray
- Department of Biology, Clark University, Worcester, Massachusetts, United States
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14
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Soler Beatty J, Molnar C, Luque CM, de Celis JF, Martín-Bermudo MD. EGFRAP encodes a new negative regulator of the EGFR acting in both normal and oncogenic EGFR/Ras-driven tissue morphogenesis. PLoS Genet 2021; 17:e1009738. [PMID: 34411095 PMCID: PMC8407591 DOI: 10.1371/journal.pgen.1009738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 08/31/2021] [Accepted: 07/23/2021] [Indexed: 12/27/2022] Open
Abstract
Activation of Ras signaling occurs in ~30% of human cancers. However, activated Ras alone is insufficient to produce malignancy. Thus, it is imperative to identify those genes cooperating with activated Ras in driving tumoral growth. In this work, we have identified a novel EGFR inhibitor, which we have named EGFRAP, for EGFR adaptor protein. Elimination of EGFRAP potentiates activated Ras-induced overgrowth in the Drosophila wing imaginal disc. We show that EGFRAP interacts physically with the phosphorylated form of EGFR via its SH2 domain. EGFRAP is expressed at high levels in regions of maximal EGFR/Ras pathway activity, such as at the presumptive wing margin. In addition, EGFRAP expression is up-regulated in conditions of oncogenic EGFR/Ras activation. Normal and oncogenic EGFR/Ras-mediated upregulation of EGRAP levels depend on the Notch pathway. We also find that elimination of EGFRAP does not affect overall organogenesis or viability. However, simultaneous downregulation of EGFRAP and its ortholog PVRAP results in defects associated with increased EGFR function. Based on these results, we propose that EGFRAP is a new negative regulator of the EGFR/Ras pathway, which, while being required redundantly for normal morphogenesis, behaves as an important modulator of EGFR/Ras-driven tissue hyperplasia. We suggest that the ability of EGFRAP to functionally inhibit the EGFR pathway in oncogenic cells results from the activation of a feedback loop leading to increase EGFRAP expression. This could act as a surveillance mechanism to prevent excessive EGFR activity and uncontrolled cell growth. Activation of Ras signalling occurs in ~30% of human cancers. However, activated Ras alone is insufficient to produce malignancy. Thus, the discovery of genes cooperating with Ras in cancer is imperative to understand tumoral growth driven by Ras activating mutations. A key output of over-activated EGFR/Ras signalling is the induction of a complex and dynamic set of transcriptional networks leading to changes in gene expression. As a result of these changes, the normal function of some genes can become adjusted in a tumorigenic context. In this work, using the Drosophila wing imaginal disc as model system, we have identified a new EGFR inhibitor, EGFRAP, which function is redundant for proper morphogenesis, yet becomes an important limiter of the overgrowth driven by oncogenic EGFR/Ras activity. We show that the specificity of EGFRAP in cells with high levels of EGFR activity arises from activation of a negative feedback loop resulting in increased EGFRAP levels. This could act to prevent excessive EGFR activity and uncontrolled cell growth. We believe the identification of other factors behaving like EGFRAP, will help in our fight against cancer, as it might lead to the identification of new therapeutic drugs affecting cancer but not normal cells, a top priority in cancer research.
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Affiliation(s)
- Jennifer Soler Beatty
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Sevilla, Spain
| | - Cristina Molnar
- Centro de Biología Molecular Severo Ochoa (UAM/CSIC), Univ. Autónoma de Madrid, Madrid, Spain
| | - Carlos M. Luque
- Centro de Biología Molecular Severo Ochoa (UAM/CSIC), Univ. Autónoma de Madrid, Madrid, Spain
| | - Jose F. de Celis
- Centro de Biología Molecular Severo Ochoa (UAM/CSIC), Univ. Autónoma de Madrid, Madrid, Spain
| | - María D. Martín-Bermudo
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Sevilla, Spain
- * E-mail:
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15
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Martins T, Meng Y, Korona B, Suckling R, Johnson S, Handford PA, Lea SM, Bray SJ. The conserved C2 phospholipid-binding domain in Delta contributes to robust Notch signalling. EMBO Rep 2021; 22:e52729. [PMID: 34347930 PMCID: PMC8490980 DOI: 10.15252/embr.202152729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/10/2021] [Accepted: 07/15/2021] [Indexed: 11/09/2022] Open
Abstract
Accurate Notch signalling is critical for development and homeostasis. Fine‐tuning of Notch–ligand interactions has substantial impact on signalling outputs. Recent structural studies have identified a conserved N‐terminal C2 domain in human Notch ligands which confers phospholipid binding in vitro. Here, we show that Drosophila ligands Delta and Serrate adopt the same C2 domain structure with analogous variations in the loop regions, including the so‐called β1‐2 loop that is involved in phospholipid binding. Mutations in the β1‐2 loop of the Delta C2 domain retain Notch binding but have impaired ability to interact with phospholipids in vitro. To investigate its role in vivo, we deleted five residues within the β1‐2 loop of endogenous Delta. Strikingly, this change compromises ligand function. The modified Delta enhances phenotypes produced by Delta loss‐of‐function alleles and suppresses that of Notch alleles. As the modified protein is present on the cell surface in normal amounts, these results argue that C2 domain phospholipid binding is necessary for robust signalling in vivo fine‐tuning the balance of trans and cis ligand–receptor interactions.
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Affiliation(s)
- Torcato Martins
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Yao Meng
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Richard Suckling
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Steven Johnson
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | | | - Susan M Lea
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Sarah J Bray
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, UK
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16
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Chang X, Zhang F, Li H, Mo D, Shen J, Zhang J. Characterization of a new mastermind allele identified from somatic mosaic screen. Cells Dev 2021; 165:203664. [PMID: 33993981 DOI: 10.1016/j.cdev.2021.203664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 01/07/2021] [Accepted: 01/22/2021] [Indexed: 11/18/2022]
Abstract
The Notch signaling pathway is highly conserved and regulates various fundamental development events. Activation of Notch signaling relies on production of the Notch intracellular domain (NICD), which assembles a transcription factor complex to turn on down-stream targets expression. The mastermind (mam) gene encodes an essential co-activator that permits NICD activity in the cell nucleus. During a somatic mosaic screen in Drosophila, an uncharacterized gene l(2)S9998 is identified as a positive regulator of the Notch signaling pathway. Genetic analysis demonstrates that l(2)S9998 functions at the level of transcriptional activation of Notch targets in the signal receiving cells. Whole genome sequencing reveals that l(2)S9998 is a novel allele of the mam gene, which is further confirmed by complementation tests. Along with three molecularly defined transposon insertions isolated from the screen, four mutants of mam are shown to modulate Notch signaling during fly wing development. Our analysis provides additional genetic resources for understanding mam function and Notch signaling regulation.
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Affiliation(s)
- Xinyue Chang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Fengchao Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Haomiao Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Dongqing Mo
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Jie Shen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Junzheng Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China.
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17
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Notch Signalling: The Multitask Manager of Inner Ear Development and Regeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1218:129-157. [DOI: 10.1007/978-3-030-34436-8_8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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18
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Uyehara CM, McKay DJ. Direct and widespread role for the nuclear receptor EcR in mediating the response to ecdysone in Drosophila. Proc Natl Acad Sci U S A 2019; 116:9893-9902. [PMID: 31019084 PMCID: PMC6525475 DOI: 10.1073/pnas.1900343116] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ecdysone pathway was among the first experimental systems employed to study the impact of steroid hormones on the genome. In Drosophila and other insects, ecdysone coordinates developmental transitions, including wholesale transformation of the larva into the adult during metamorphosis. Like other hormones, ecdysone controls gene expression through a nuclear receptor, which functions as a ligand-dependent transcription factor. Although it is clear that ecdysone elicits distinct transcriptional responses within its different target tissues, the role of its receptor, EcR, in regulating target gene expression is incompletely understood. In particular, EcR initiates a cascade of transcription factor expression in response to ecdysone, making it unclear which ecdysone-responsive genes are direct EcR targets. Here, we use the larval-to-prepupal transition of developing wings to examine the role of EcR in gene regulation. Genome-wide DNA binding profiles reveal that EcR exhibits widespread binding across the genome, including at many canonical ecdysone response genes. However, the majority of its binding sites reside at genes with wing-specific functions. We also find that EcR binding is temporally dynamic, with thousands of binding sites changing over time. RNA-seq reveals that EcR acts as both a temporal gate to block precocious entry to the next developmental stage as well as a temporal trigger to promote the subsequent program. Finally, transgenic reporter analysis indicates that EcR regulates not only temporal changes in target enhancer activity but also spatial patterns. Together, these studies define EcR as a multipurpose, direct regulator of gene expression, greatly expanding its role in coordinating developmental transitions.
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Affiliation(s)
- Christopher M Uyehara
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Daniel J McKay
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599;
- Department of Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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19
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A refutation to 'A new A-P compartment boundary and organizer in holometabolous insect wings'. Sci Rep 2019; 9:7049. [PMID: 31065001 PMCID: PMC6505030 DOI: 10.1038/s41598-019-42668-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/05/2019] [Indexed: 12/25/2022] Open
Abstract
We respond to a recent report by Abbasi and Marcus who present two main findings: first they argue that there is an organiser and a compartment boundary within the posterior compartment of the butterfly wing. Second, they present evidence for a previously undiscovered lineage boundary near wing vein 5 in Drosophila, a boundary that delineates a "far posterior" compartment. Clones of cells were marked with the yellow mutation and they reported that these clones always fail to cross a line close to vein 5 on the Drosophila wing. In our hands yellow proved an unusable marker for clones in the wing blade and therefore we reexamined the matter. We marked clones of cells with multiple wing hairs or forked and found a substantial proportion of these clones cross the proposed lineage boundary near vein 5, in conflict with their findings and conclusion. As internal controls we showed that these same clones respect the other two well established compartment boundaries: the anteroposterior compartment boundary is always respected. The dorsoventral boundary is mostly respected, and is crossed only by clones that are induced early in development, consistent with many reports. We question the validity of Abbasi and Marcus' conclusions regarding the butterfly wing but present no new data.Arising from: R. Abbasi and J. M. Marcus Sci. Rep. 7, 16337 (2017); https://doi.org/10.1038/s41598-017-16553-5 .
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20
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Fic W, Faria C, St Johnston D. IMP regulates Kuzbanian to control the timing of Notch signalling in Drosophila follicle cells. Development 2019; 146:dev.168963. [PMID: 30635283 PMCID: PMC6361131 DOI: 10.1242/dev.168963] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 12/19/2018] [Indexed: 12/31/2022]
Abstract
The timing of Drosophila egg chamber development is controlled by a germline Delta signal that activates Notch in the follicle cells to induce them to cease proliferation and differentiate. Here, we report that follicle cells lacking the RNA-binding protein IMP go through one extra division owing to a delay in the Delta-dependent S2 cleavage of Notch. The timing of Notch activation has previously been shown to be controlled by cis-inhibition by Delta in the follicle cells, which is relieved when the miRNA pathway represses Delta expression. imp mutants are epistatic to Delta mutants and give an additive phenotype with belle and Dicer-1 mutants, indicating that IMP functions independently of both cis-inhibition and the miRNA pathway. We find that the imp phenotype is rescued by overexpression of Kuzbanian, the metalloprotease that mediates the Notch S2 cleavage. Furthermore, Kuzbanian is not enriched at the apical membrane in imp mutants, accumulating instead in late endosomes. Thus, IMP regulates Notch signalling by controlling the localisation of Kuzbanian to the apical domain, where Notch cleavage occurs, revealing a novel regulatory step in the Notch pathway.
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Affiliation(s)
| | | | - Daniel St Johnston
- The Gurdon Institute and The Department of Genetics, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, UK
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21
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Alabi RO, Farber G, Blobel CP. Intriguing Roles for Endothelial ADAM10/Notch Signaling in the Development of Organ-Specific Vascular Beds. Physiol Rev 2019; 98:2025-2061. [PMID: 30067156 DOI: 10.1152/physrev.00029.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The vasculature is a remarkably interesting, complex, and interconnected organ. It provides a conduit for oxygen and nutrients, filtration of waste products, and rapid communication between organs. Much remains to be learned about the specialized vascular beds that fulfill these diverse, yet vital functions. This review was prompted by the discovery that Notch signaling in mouse endothelial cells is crucial for the development of specialized vascular beds found in the heart, kidneys, liver, intestines, and bone. We will address the intriguing questions raised by the role of Notch signaling and that of its regulator, the metalloprotease ADAM10, in the development of specialized vascular beds. We will cover fundamentals of ADAM10/Notch signaling, the concept of Notch-dependent cell fate decisions, and how these might govern the development of organ-specific vascular beds through angiogenesis or vasculogenesis. We will also consider common features of the affected vessels, including the presence of fenestra or sinusoids and their occurrence in portal systems with two consecutive capillary beds. We hope to stimulate further discussion and study of the role of ADAM10/Notch signaling in the development of specialized vascular structures, which might help uncover new targets for the repair of vascular beds damaged in conditions like coronary artery disease and glomerulonephritis.
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Affiliation(s)
- Rolake O Alabi
- Weill Cornell/Rockefeller/Sloan-Kettering Tri-Institutional MD-PhD Program, New York, New York ; Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, New York ; Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, New York ; Department of Medicine, Weill Cornell Medicine, New York, New York ; and Institute for Advanced Study, Technical University Munich , Munich , Germany
| | - Gregory Farber
- Weill Cornell/Rockefeller/Sloan-Kettering Tri-Institutional MD-PhD Program, New York, New York ; Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, New York ; Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, New York ; Department of Medicine, Weill Cornell Medicine, New York, New York ; and Institute for Advanced Study, Technical University Munich , Munich , Germany
| | - Carl P Blobel
- Weill Cornell/Rockefeller/Sloan-Kettering Tri-Institutional MD-PhD Program, New York, New York ; Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, New York ; Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, New York ; Department of Medicine, Weill Cornell Medicine, New York, New York ; and Institute for Advanced Study, Technical University Munich , Munich , Germany
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22
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Jovanović B, Jovanović N, Cvetković VJ, Matić S, Stanić S, Whitley EM, Mitrović TL. The effects of a human food additive, titanium dioxide nanoparticles E171, on Drosophila melanogaster - a 20 generation dietary exposure experiment. Sci Rep 2018; 8:17922. [PMID: 30560898 PMCID: PMC6298969 DOI: 10.1038/s41598-018-36174-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 10/26/2018] [Indexed: 01/03/2023] Open
Abstract
In this study, fruit flies (Drosophila melanogaster) were exposed to an estimated daily human E171 consumption concentration for 20 generations. Exposure to E171 resulted in: a change in normal developmental and reproductive dynamics, reduced fecundity after repetitive breeding, increased genotoxicity, the appearance of aberrant phenotypes and morphologic changes to the adult fat body. Marks of adaptive evolution and directional selection were also exhibited. The larval stages were at a higher risk of sustaining damage from E171 as they had a slower elimination rate of TiO2 compared to the adults. This is particularly worrisome, since among the human population, children tend to consume higher daily concentrations of E171 than do adults. The genotoxic effect of E171 was statistically higher in each subsequent generation compared to the previous one. Aberrant phenotypes were likely caused by developmental defects induced by E171, and were not mutations, since the phenotypic features were not transferred to any progeny even after 5 generations of consecutive crossbreeding. Therefore, exposure to E171 during the early developmental period carries a higher risk of toxicity. The fact that the daily human consumption concentration of E171 interferes with and influences fruit fly physiological, ontogenetic, genotoxic, and adaptive processes certainly raises safety concerns.
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Affiliation(s)
- Boris Jovanović
- Department of Natural Resource Ecology and Management, Iowa State University, Ames, IA, USA.
| | - Nikola Jovanović
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
| | - Vladimir J Cvetković
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
| | - Sanja Matić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Kragujevac, Serbia
| | - Snežana Stanić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Kragujevac, Serbia
| | | | - Tatjana Lj Mitrović
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
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23
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Salazar JL, Yamamoto S. Integration of Drosophila and Human Genetics to Understand Notch Signaling Related Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1066:141-185. [PMID: 30030826 PMCID: PMC6233323 DOI: 10.1007/978-3-319-89512-3_8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Notch signaling research dates back to more than one hundred years, beginning with the identification of the Notch mutant in the fruit fly Drosophila melanogaster. Since then, research on Notch and related genes in flies has laid the foundation of what we now know as the Notch signaling pathway. In the 1990s, basic biological and biochemical studies of Notch signaling components in mammalian systems, as well as identification of rare mutations in Notch signaling pathway genes in human patients with rare Mendelian diseases or cancer, increased the significance of this pathway in human biology and medicine. In the 21st century, Drosophila and other genetic model organisms continue to play a leading role in understanding basic Notch biology. Furthermore, these model organisms can be used in a translational manner to study underlying mechanisms of Notch-related human diseases and to investigate the function of novel disease associated genes and variants. In this chapter, we first briefly review the major contributions of Drosophila to Notch signaling research, discussing the similarities and differences between the fly and human pathways. Next, we introduce several biological contexts in Drosophila in which Notch signaling has been extensively characterized. Finally, we discuss a number of genetic diseases caused by mutations in genes in the Notch signaling pathway in humans and we expand on how Drosophila can be used to study rare genetic variants associated with these and novel disorders. By combining modern genomics and state-of-the art technologies, Drosophila research is continuing to reveal exciting biology that sheds light onto mechanisms of disease.
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Affiliation(s)
- Jose L Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, USA.
- Program in Developmental Biology, BCM, Houston, TX, USA.
- Department of Neuroscience, BCM, Houston, TX, USA.
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA.
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24
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Mann ZF, Gálvez H, Pedreno D, Chen Z, Chrysostomou E, Żak M, Kang M, Canden E, Daudet N. Shaping of inner ear sensory organs through antagonistic interactions between Notch signalling and Lmx1a. eLife 2017; 6:e33323. [PMID: 29199954 PMCID: PMC5724992 DOI: 10.7554/elife.33323] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 12/02/2017] [Indexed: 12/19/2022] Open
Abstract
The mechanisms of formation of the distinct sensory organs of the inner ear and the non-sensory domains that separate them are still unclear. Here, we show that several sensory patches arise by progressive segregation from a common prosensory domain in the embryonic chicken and mouse otocyst. This process is regulated by mutually antagonistic signals: Notch signalling and Lmx1a. Notch-mediated lateral induction promotes prosensory fate. Some of the early Notch-active cells, however, are normally diverted from this fate and increasing lateral induction produces misshapen or fused sensory organs in the chick. Conversely Lmx1a (or cLmx1b in the chick) allows sensory organ segregation by antagonizing lateral induction and promoting commitment to the non-sensory fate. Our findings highlight the dynamic nature of sensory patch formation and the labile character of the sensory-competent progenitors, which could have facilitated the emergence of new inner ear organs and their functional diversification in the course of evolution.
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Affiliation(s)
- Zoe F Mann
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | - Héctor Gálvez
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | - David Pedreno
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | - Ziqi Chen
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | | | - Magdalena Żak
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | - Miso Kang
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
| | | | - Nicolas Daudet
- The Ear InstituteUniversity College LondonLondonUnited Kingdom
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25
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Chan SKK, Cerda-Moya G, Stojnic R, Millen K, Fischer B, Fexova S, Skalska L, Gomez-Lamarca M, Pillidge Z, Russell S, Bray SJ. Role of co-repressor genomic landscapes in shaping the Notch response. PLoS Genet 2017; 13:e1007096. [PMID: 29155828 PMCID: PMC5714389 DOI: 10.1371/journal.pgen.1007096] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 12/04/2017] [Accepted: 11/01/2017] [Indexed: 11/18/2022] Open
Abstract
Repressors are frequently deployed to limit the transcriptional response to signalling pathways. For example, several co-repressors interact directly with the DNA-binding protein CSL and are proposed to keep target genes silenced in the absence of Notch activity. However, the scope of their contributions remains unclear. To investigate co-repressor activity in the context of this well defined signalling pathway, we have analysed the genome-wide binding profile of the best-characterized CSL co-repressor in Drosophila, Hairless, and of a second CSL interacting repressor, SMRTER. As predicted there was significant overlap between Hairless and its CSL DNA-binding partner, both in Kc cells and in wing discs, where they were predominantly found in chromatin with active enhancer marks. However, while the Hairless complex was widely present at some Notch regulated enhancers in the wing disc, no binding was detected at others, indicating that it is not essential for silencing per se. Further analysis of target enhancers confirmed differential requirements for Hairless. SMRTER binding significantly overlapped with Hairless, rather than complementing it, and many enhancers were apparently co-bound by both factors. Our analysis indicates that the actions of Hairless and SMRTER gate enhancers to Notch activity and to Ecdysone signalling respectively, to ensure that the appropriate levels and timing of target gene expression are achieved. The communication between cells that occurs during development, as well as in disease contexts, involves a small number of signalling pathways of which the Notch pathway is one. One outstanding question is how these pathways can bring about different gene responses in different contexts. As gene expression is co-ordinated by a mixture of activators and repressors, we set out to investigate whether the distribution of repressors across the genome is important in shaping whether genes are able to respond to Notch activity. Our results from analyzing the binding profile of two repressors, Hairless and SMRTER, show that, in many cases, they are not essential for preventing a gene from responding. Instead they are deployed at a limited number of genetic loci where they gate the response, helping to set a threshold for gene activation. Perturbations to their function lead to enhanced gene expression in limited territories rather than to new programmes of gene expression. Their main role therefore is to restrict the time or levels of signal that a gene needs to receive before it will respond.
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Affiliation(s)
- Stephen K. K. Chan
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Gustavo Cerda-Moya
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Robert Stojnic
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
| | - Kat Millen
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Bettina Fischer
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Silvie Fexova
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Lenka Skalska
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Maria Gomez-Lamarca
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Zoe Pillidge
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Steven Russell
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Sarah J. Bray
- Department of Physiology Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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26
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Berndt N, Seib E, Kim S, Troost T, Lyga M, Langenbach J, Haensch S, Kalodimou K, Delidakis C, Klein T. Ubiquitylation-independent activation of Notch signalling by Delta. eLife 2017; 6:27346. [PMID: 28960177 PMCID: PMC5675594 DOI: 10.7554/elife.27346] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/28/2017] [Indexed: 12/29/2022] Open
Abstract
Ubiquitylation (ubi) by the E3-ligases Mindbomb1 (Mib1) and Neuralized (Neur) is required for activation of the DSL ligands Delta (Dl) and Serrate (Ser) to activate Notch signalling. These ligases transfer ubiquitin to lysines of the ligands' intracellular domains (ICDs), which sends them into an Epsin-dependent endocytic pathway. Here, we have tested the requirement of ubi of Dl for signalling. We found that Dl requires ubi for its full function, but can also signal in two ubi-independent modes, one dependent and one independent of Neur. We identified two neural lateral specification processes where Dl signals in an ubi-independent manner. Neur, which is needed for these processes, was shown to be able to activate Dl in an ubi-independent manner. Our analysis suggests that one important role of DSL protein ubi by Mib1 is their release from cis-inhibitory interactions with Notch, enabling them to trans-activate Notch on adjacent cells.
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Affiliation(s)
- Nicole Berndt
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Ekaterina Seib
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Soya Kim
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany.,Molekulare Zellbiologie, Institut I für Anatomie, Uniklinik Köln, Universität zu Köln, Köln, Germany
| | - Tobias Troost
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Marvin Lyga
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Jessica Langenbach
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Sebastian Haensch
- Center of Advanced Imaging, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
| | - Konstantina Kalodimou
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece.,Department of Biology, University of Crete, Heraklion, Greece
| | - Christos Delidakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece.,Department of Biology, University of Crete, Heraklion, Greece
| | - Thomas Klein
- Institute of Genetics, Heinrich-Heine-Universitaet Duesseldorf, Duesseldorf, Germany
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Deshmukh R, Baral S, Gandhimathi A, Kuwalekar M, Kunte K. Mimicry in butterflies: co-option and a bag of magnificent developmental genetic tricks. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 7. [PMID: 28913870 DOI: 10.1002/wdev.291] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 07/04/2017] [Accepted: 07/20/2017] [Indexed: 01/05/2023]
Abstract
Butterfly wing patterns are key adaptations that are controlled by remarkable developmental and genetic mechanisms that facilitate rapid evolutionary change. With swift advancements in the fields of genomics and genetic manipulations, identifying the regulators of wing development and mimetic wing patterns has become feasible even in nonmodel organisms such as butterflies. Recent mapping and gene expression studies have identified single switch loci of major effects such as transcription factors and supergenes as the main drivers of adaptive evolution of mimetic and polymorphic butterfly wing patterns. We highlight several of these examples, with emphasis on doublesex, optix, WntA and other dynamic, yet essential, master regulators that control critical color variation and sex-specific traits. Co-option emerges as a predominant theme, where typically embryonic and other early-stage developmental genes and networks have been rewired to regulate polymorphic and sex-limited mimetic wing patterns in iconic butterfly adaptations. Drawing comparisons from our knowledge of wing development in Drosophila, we illustrate the functional space of genes that have been recruited to regulate butterfly wing patterns. We also propose a developmental pathway that potentially results in dorsoventral mismatch in butterfly wing patterns. Such dorsoventrally mismatched color patterns modulate signal components of butterfly wings that are used in intra- and inter-specific communication. Recent advances-fuelled by RNAi-mediated knockdowns and CRISPR/Cas9-based genomic edits-in the developmental genetics of butterfly wing patterns, and the underlying biological diversity and complexity of wing coloration, are pushing butterflies as an emerging model system in ecological genetics and evolutionary developmental biology. WIREs Dev Biol 2018, 7:e291. doi: 10.1002/wdev.291 This article is categorized under: Gene Expression and Transcriptional Hierarchies > Regulatory Mechanisms Comparative Development and Evolution > Regulation of Organ Diversity Comparative Development and Evolution > Evolutionary Novelties.
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Affiliation(s)
| | - Saurav Baral
- National Centre for Biological Sciences, Bengaluru, India
| | - A Gandhimathi
- National Centre for Biological Sciences, Bengaluru, India
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28
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Ventrella R, Kaplan N, Getsios S. Asymmetry at cell-cell interfaces direct cell sorting, boundary formation, and tissue morphogenesis. Exp Cell Res 2017; 358:58-64. [PMID: 28322822 PMCID: PMC5544567 DOI: 10.1016/j.yexcr.2017.03.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 03/13/2017] [Indexed: 01/22/2023]
Abstract
During development, cells of seemingly homogenous character sort themselves out into distinct compartments in order to generate cell types with specialized features that support tissue morphogenesis and function. This process is often driven by receptors at the cell membrane that probe the extracellular microenvironment for specific ligands and alter downstream signaling pathways impacting transcription, cytoskeletal organization, and cell adhesion to regulate cell sorting and subsequent boundary formation. This review will focus on two of these receptor families, Eph and Notch, both of which are intrinsically non-adhesive and are activated by a unique set of ligands that are asymmetrically distributed from their receptor on neighboring cells. Understanding the requirement of asymmetric ligand-receptor signaling at the membrane under homeostatic conditions gives insight into how misregulation of these pathways contributes to boundary disruption in diseases like cancer.
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Affiliation(s)
- Rosa Ventrella
- Department of Dermatology, Northwestern University, 303 E. Chicago Ave, Chicago, IL 60611, USA
| | - Nihal Kaplan
- Department of Dermatology, Northwestern University, 303 E. Chicago Ave, Chicago, IL 60611, USA
| | - Spiro Getsios
- Department of Dermatology, Northwestern University, 303 E. Chicago Ave, Chicago, IL 60611, USA.
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29
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Hall ET, Pradhan-Sundd T, Samnani F, Verheyen EM. The protein phosphatase 4 complex promotes the Notch pathway and wingless transcription. Biol Open 2017; 6:1165-1173. [PMID: 28652317 PMCID: PMC5576076 DOI: 10.1242/bio.025221] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The Wnt/Wingless (Wg) pathway controls cell fate specification, tissue differentiation and organ development across organisms. Using an in vivo RNAi screen to identify novel kinase and phosphatase regulators of the Wg pathway, we identified subunits of the serine threonine phosphatase Protein Phosphatase 4 (PP4). Knockdown of the catalytic and regulatory subunits of PP4 cause reductions in the Wg pathway targets Senseless and Distal-less. We find that PP4 regulates the Wg pathway by controlling Notch-driven wg transcription. Genetic interaction experiments identified that PP4 likely promotes Notch signaling within the nucleus of the Notch-receiving cell. Although the PP4 complex is implicated in various cellular processes, its role in the regulation of Wg and Notch pathways was previously uncharacterized. Our study identifies a novel role of PP4 in regulating Notch pathway, resulting in aberrations in Notch-mediated transcriptional regulation of the Wingless ligand. Furthermore, we show that PP4 regulates proliferation independent of its interaction with Notch. Summary: The protein phosphatase 4 complex promotes Notch signaling and target gene expression during Drosophila wing development.
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Affiliation(s)
- Eric T Hall
- Department of Molecular Biology and Biochemistry, Centre for Cell Biology, Development and Disease, Simon Fraser University, British Columbia V5A 1S6, Canada
| | - Tirthadipa Pradhan-Sundd
- Department of Molecular Biology and Biochemistry, Centre for Cell Biology, Development and Disease, Simon Fraser University, British Columbia V5A 1S6, Canada
| | - Faaria Samnani
- Department of Molecular Biology and Biochemistry, Centre for Cell Biology, Development and Disease, Simon Fraser University, British Columbia V5A 1S6, Canada
| | - Esther M Verheyen
- Department of Molecular Biology and Biochemistry, Centre for Cell Biology, Development and Disease, Simon Fraser University, British Columbia V5A 1S6, Canada
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Praxenthaler H, Nagel AC, Schulz A, Zimmermann M, Meier M, Schmid H, Preiss A, Maier D. Hairless-binding deficient Suppressor of Hairless alleles reveal Su(H) protein levels are dependent on complex formation with Hairless. PLoS Genet 2017; 13:e1006774. [PMID: 28475577 PMCID: PMC5438185 DOI: 10.1371/journal.pgen.1006774] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 05/19/2017] [Accepted: 04/21/2017] [Indexed: 11/19/2022] Open
Abstract
Cell fate choices during metazoan development are driven by the highly conserved Notch signalling pathway. Notch receptor activation results in release of the Notch intracellular domain (NICD) that acts as transcriptional co-activator of the DNA-binding protein CSL. In the absence of signal, a repressor complex consisting of CSL bound to co-repressors silences Notch target genes. The Drosophila repressor complex contains the fly CSL orthologue Suppressor of Hairless [Su(H)] and Hairless (H). The Su(H)-H crystal structure revealed a large conformational change within Su(H) upon H binding, precluding interactions with NICD. Based on the structure, several sites in Su(H) and H were determined to specifically engage in complex formation. In particular, three mutations in Su(H) were identified that affect interactions with the repressor H but not the activator NICD. To analyse the effects these mutants have on normal fly development, we introduced these mutations into the native Su(H) locus by genome engineering. We show that the three H-binding deficient Su(H) alleles behave similarly. As these mutants lack the ability to form the repressor complex, Notch signalling activity is strongly increased in homozygotes, comparable to a complete loss of H activity. Unexpectedly, we find that the abundance of the three mutant Su(H) protein variants is altered, as is that of wild type Su(H) protein in the absence of H protein. In the presence of NICD, however, Su(H) mutant protein persists. Apparently, Su(H) protein levels depend on the interactions with H as well as with NICD. Based on these results, we propose that in vivo levels of Su(H) protein are stabilised by interactions with transcription-regulator complexes.
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Affiliation(s)
- Heiko Praxenthaler
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Anja C. Nagel
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Adriana Schulz
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Mirjam Zimmermann
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Markus Meier
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Hannes Schmid
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Anette Preiss
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
| | - Dieter Maier
- Institute of Genetics (240), University of Hohenheim, Stuttgart, Germany
- * E-mail:
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31
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Shimizu H, Wilkin MB, Woodcock SA, Bonfini A, Hung Y, Mazaleyrat S, Baron M. The Drosophila ZO-1 protein Polychaetoid suppresses Deltex-regulated Notch activity to modulate germline stem cell niche formation. Open Biol 2017; 7:rsob.160322. [PMID: 28424321 PMCID: PMC5413905 DOI: 10.1098/rsob.160322] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/13/2017] [Indexed: 11/24/2022] Open
Abstract
The developmental signalling protein Notch can be proteolytically activated following ligand-interaction at the cell surface, or can be activated independently of its ligands, following Deltex (Dx)-induced Notch endocytosis and trafficking to the lysosomal membrane. The means by which different pools of Notch are directed towards these alternative outcomes remains poorly understood. We found that the Drosophila ZO-1 protein Polychaetoid (Pyd) suppresses specifically the Dx-induced form of Notch activation both in vivo and in cell culture assays. In vivo we confirmed the physiological relevance and direction of the Pyd/Dx interaction by showing that the expanded ovary stem cell niche phenotypes of pyd mutants require the presence of functional Dx and other components that are specific to the Dx-induced Notch activation mechanism. In S2 cells we found that Pyd can form a complex with Dx and Notch at the cell surface and reduce Dx-induced Notch endocytosis. Similar to other known activities of ZO-1 family proteins, the action of Pyd on Dx-induced endocytosis and signalling was found to be cell density dependent. Thus, together, our results suggest an alternative means by which external cues can tune Notch signalling through Pyd regulation of Dx-induced Notch trafficking.
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Affiliation(s)
- Hideyuki Shimizu
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Marian B Wilkin
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Simon A Woodcock
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Alessandro Bonfini
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Yvonne Hung
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Sabine Mazaleyrat
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
| | - Martin Baron
- University of Manchester, School of Biological Sciences, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PL, UK
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32
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Zaytseva O, Quinn LM. Controlling the Master: Chromatin Dynamics at the MYC Promoter Integrate Developmental Signaling. Genes (Basel) 2017; 8:genes8040118. [PMID: 28398229 PMCID: PMC5406865 DOI: 10.3390/genes8040118] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/15/2017] [Accepted: 04/07/2017] [Indexed: 02/06/2023] Open
Abstract
The transcription factor and cell growth regulator MYC is potently oncogenic and estimated to contribute to most cancers. Decades of attempts to therapeutically target MYC directly have not resulted in feasible clinical applications, and efforts have moved toward indirectly targeting MYC expression, function and/or activity to treat MYC-driven cancer. A multitude of developmental and growth signaling pathways converge on the MYC promoter to modulate transcription through their downstream effectors. Critically, even small increases in MYC abundance (<2 fold) are sufficient to drive overproliferation; however, the details of how oncogenic/growth signaling networks regulate MYC at the level of transcription remain nebulous even during normal development. It is therefore essential to first decipher mechanisms of growth signal-stimulated MYC transcription using in vivo models, with intact signaling environments, to determine exactly how these networks are dysregulated in human cancer. This in turn will provide new modalities and approaches to treat MYC-driven malignancy. Drosophila genetic studies have shed much light on how complex networks signal to transcription factors and enhancers to orchestrate Drosophila MYC (dMYC) transcription, and thus growth and patterning of complex multicellular tissue and organs. This review will discuss the many pathways implicated in patterning MYC transcription during development and the molecular events at the MYC promoter that link signaling to expression. Attention will also be drawn to parallels between mammalian and fly regulation of MYC at the level of transcription.
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Affiliation(s)
- Olga Zaytseva
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia.
- School of Biomedical Sciences, University of Melbourne, Parkville 3010, Australia.
| | - Leonie M Quinn
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia.
- School of Biomedical Sciences, University of Melbourne, Parkville 3010, Australia.
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33
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Lee TV, Pandey A, Jafar-Nejad H. Xylosylation of the Notch receptor preserves the balance between its activation by trans-Delta and inhibition by cis-ligands in Drosophila. PLoS Genet 2017; 13:e1006723. [PMID: 28394891 PMCID: PMC5402982 DOI: 10.1371/journal.pgen.1006723] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 04/24/2017] [Accepted: 03/29/2017] [Indexed: 01/02/2023] Open
Abstract
The Drosophila glucoside xylosyltransferase Shams xylosylates Notch and inhibits Notch signaling in specific contexts including wing vein development. However, the molecular mechanisms underlying context-specificity of the shams phenotype is not known. Considering the role of Delta-Notch signaling in wing vein formation, we hypothesized that Shams might affect Delta-mediated Notch signaling in Drosophila. Using genetic interaction studies, we find that altering the gene dosage of Delta affects the wing vein and head bristle phenotypes caused by loss of Shams or by mutations in the Notch xylosylation sites. Clonal analysis suggests that loss of shams promotes Delta-mediated Notch activation. Further, Notch trans-activation by ectopically overexpressed Delta shows a dramatic increase upon loss of shams. In agreement with the above in vivo observations, cell aggregation and ligand-receptor binding assays show that shams knock-down in Notch-expressing cells enhances the binding between Notch and trans-Delta without affecting the binding between Notch and trans-Serrate and cell surface levels of Notch. Loss of Shams does not impair the cis-inhibition of Notch by ectopic overexpression of ligands in vivo or the interaction of Notch and cis-ligands in S2 cells. Nevertheless, removing one copy of endogenous ligands mimics the effects of loss shams on Notch trans-activation by ectopic Delta. This favors the notion that trans-activation of Notch by Delta overcomes the cis-inhibition of Notch by endogenous ligands upon loss of shams. Taken together, our data suggest that xylosylation selectively impedes the binding of Notch with trans-Delta without affecting its binding with cis-ligands and thereby assists in determining the balance of Notch receptor's response to cis-ligands vs. trans-Delta during Drosophila development.
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Affiliation(s)
- Tom V. Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Ashutosh Pandey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Hamed Jafar-Nejad
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
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34
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Evolutionary conservation of Notch signaling inhibition by TMEM131L overexpression. Biochem Biophys Res Commun 2017; 486:909-915. [PMID: 28347816 DOI: 10.1016/j.bbrc.2017.03.123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 03/23/2017] [Indexed: 12/12/2022]
Abstract
Human KIAA0922/TMEM131L encodes a transmembrane protein, TMEM131L, that regulates the canonical Wnt/β-catenin signaling pathway by eliciting the lysosome-dependent degradation of phosphorylated LRP6 co-receptor. Here, we use a heterospecific Drosophila transgenic model to examine the potential evolutionary conservation of TMEM131L function. Analysis of TMEM131L transgenic flies shows that TMEM131L interference with the Wnt pathway results primarily from a Notch-dependent decrease in Wingless production. Consistently, lentivirus-mediated overexpression of TMEM131L in human CD34+ hematopoietic progenitor cells leads to decreased susceptibility to Notch1 ligation and defective commitment toward the T lineage. These results show that TMEM131L corresponds to an evolutionary conserved regulator of the Notch signaling pathway.
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35
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Yeung K, Boija A, Karlsson E, Holmqvist PH, Tsatskis Y, Nisoli I, Yap D, Lorzadeh A, Moksa M, Hirst M, Aparicio S, Fanto M, Stenberg P, Mannervik M, McNeill H. Atrophin controls developmental signaling pathways via interactions with Trithorax-like. eLife 2017; 6:e23084. [PMID: 28327288 PMCID: PMC5409829 DOI: 10.7554/elife.23084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/15/2017] [Indexed: 12/30/2022] Open
Abstract
Mutations in human Atrophin1, a transcriptional corepressor, cause dentatorubral-pallidoluysian atrophy, a neurodegenerative disease. Drosophila Atrophin (Atro) mutants display many phenotypes, including neurodegeneration, segmentation, patterning and planar polarity defects. Despite Atro's critical role in development and disease, relatively little is known about Atro's binding partners and downstream targets. We present the first genomic analysis of Atro using ChIP-seq against endogenous Atro. ChIP-seq identified 1300 potential direct targets of Atro including engrailed, and components of the Dpp and Notch signaling pathways. We show that Atro regulates Dpp and Notch signaling in larval imaginal discs, at least partially via regulation of thickveins and fringe. In addition, bioinformatics analyses, sequential ChIP and coimmunoprecipitation experiments reveal that Atro interacts with the Drosophila GAGA Factor, Trithorax-like (Trl), and they bind to the same loci simultaneously. Phenotypic analyses of Trl and Atro clones suggest that Atro is required to modulate the transcription activation by Trl in larval imaginal discs. Taken together, these data indicate that Atro is a major Trl cofactor that functions to moderate developmental gene transcription.
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Affiliation(s)
- Kelvin Yeung
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Ann Boija
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Edvin Karlsson
- Department of Molecular Biology, Umeå University, Umeå, Sweden
- Division of CBRN Security and Defence, FOI-Swedish Defence Research Agency, Umeå, Sweden
| | - Per-Henrik Holmqvist
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Yonit Tsatskis
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Ilaria Nisoli
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King’s College London, London, United Kingdom
| | - Damian Yap
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Alireza Lorzadeh
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Michelle Moksa
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Martin Hirst
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Samuel Aparicio
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Manolis Fanto
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King’s College London, London, United Kingdom
| | - Per Stenberg
- Department of Molecular Biology, Umeå University, Umeå, Sweden
- Division of CBRN Security and Defence, FOI-Swedish Defence Research Agency, Umeå, Sweden
| | - Mattias Mannervik
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Helen McNeill
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
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Shukla JP, Deshpande G, Shashidhara LS. Ataxin 2-binding protein 1 is a context-specific positive regulator of Notch signaling during neurogenesis in Drosophila melanogaster. Development 2017; 144:905-915. [PMID: 28174239 DOI: 10.1242/dev.140657] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 01/18/2017] [Indexed: 12/28/2022]
Abstract
The role of the Notch pathway during the lateral inhibition that underlies binary cell fate choice is extensively studied, but the context specificity that generates diverse outcomes is less well understood. In the peripheral nervous system of Drosophila melanogaster, differential Notch signaling between cells of the proneural cluster orchestrates sensory organ specification. Here we report functional analysis of Drosophila Ataxin 2-binding protein 1 (A2BP1) during this process. Its human ortholog is linked to type 2 spinocerebellar ataxia and other complex neuronal disorders. Downregulation of Drosophila A2BP1 in the proneural cluster increases adult sensory bristle number, whereas its overexpression results in loss of bristles. We show that A2BP1 regulates sensory organ specification by potentiating Notch signaling. Supporting its direct involvement, biochemical analysis shows that A2BP1 is part of the Suppressor of Hairless [Su(H)] complex in the presence and absence of Notch. However, in the absence of Notch signaling, the A2BP1 interacting fraction of Su(H) does not associate with the repressor proteins Groucho and CtBP. We propose a model explaining the requirement of A2BP1 as a positive regulator of context-specific Notch activity.
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Affiliation(s)
- Jay Prakash Shukla
- Indian Institute of Science Education and Research Pune, Dr Homi Bhabha Road, Pune, Maharashtra 411008, India
| | - Girish Deshpande
- Indian Institute of Science Education and Research Pune, Dr Homi Bhabha Road, Pune, Maharashtra 411008, India.,Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - L S Shashidhara
- Indian Institute of Science Education and Research Pune, Dr Homi Bhabha Road, Pune, Maharashtra 411008, India
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37
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Sabat D, Patnaik A, Ekka B, Dash P, Mishra M. Investigation of titania nanoparticles on behaviour and mechanosensory organ of Drosophila melanogaster. Physiol Behav 2016; 167:76-85. [DOI: 10.1016/j.physbeh.2016.08.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 08/06/2016] [Accepted: 08/30/2016] [Indexed: 12/13/2022]
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Nguyen MB, Vuong LT, Choi KW. Ebi modulates wing growth by ubiquitin-dependent downregulation of Crumbs in Drosophila. Development 2016; 143:3506-3513. [PMID: 27702784 DOI: 10.1242/dev.142059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Accepted: 08/12/2016] [Indexed: 12/11/2022]
Abstract
Notch signaling at the dorsoventral (DV) boundary is essential for patterning and growth of wings in Drosophila The WD40 domain protein Ebi has been implicated in the regulation of Notch signaling at the DV boundary. Here we show that Ebi regulates wing growth by antagonizing the function of the transmembrane protein Crumbs (Crb). Ebi physically binds to the extracellular domain of Crb (Crbext), and this interaction is specifically mediated by WD40 repeats 7-8 of Ebi and a laminin G domain of Crbext Wing notching resulting from reduced levels of Ebi is suppressed by decreasing the Crb function. Consistent with this antagonistic genetic relationship, Ebi knockdown in the DV boundary elevates the Crb protein level. Furthermore, we show that Ebi is required for downregulation of Crb by ubiquitylation. Taken together, we propose that the interplay of Crb expression in the DV boundary and ubiquitin-dependent Crb downregulation by Ebi provides a mechanism for the maintenance of Notch signaling during wing development.
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Affiliation(s)
- Minh Binh Nguyen
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
| | - Linh Thuong Vuong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
| | - Kwang-Wook Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
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The Ecdysone and Notch Pathways Synergistically Regulate Cut at the Dorsal-Ventral Boundary in Drosophila Wing Discs. J Genet Genomics 2016; 43:179-86. [PMID: 27117286 DOI: 10.1016/j.jgg.2016.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/05/2016] [Accepted: 03/04/2016] [Indexed: 11/23/2022]
Abstract
Metazoan development requires coordination of signaling pathways to regulate patterns of gene expression. In Drosophila, the wing imaginal disc provides an excellent model for the study of how signaling pathways interact to regulate pattern formation. The determination of the dorsal-ventral (DV) boundary of the wing disc depends on the Notch pathway, which is activated along the DV boundary and induces the expression of the homeobox transcription factor, Cut. Here, we show that Broad (Br), a zinc-finger transcription factor, is also involved in regulating Cut expression in the DV boundary region. However, Br expression is not regulated by Notch signaling in wing discs, while ecdysone signaling is the upstream signal that induces Br for Cut upregulation. Also, we find that the ecdysone-Br cascade upregulates cut-lacZ expression, a reporter containing a 2.7 kb cut enhancer region, implying that ecdysone signaling, similar to Notch, regulates cut at the transcriptional level. Collectively, our findings reveal that the Notch and ecdysone signaling pathways synergistically regulate Cut expression for proper DV boundary formation in the wing disc. Additionally, we show br promotes Delta, a Notch ligand, near the DV boundary to suppress aberrant high Notch activity, indicating further interaction between the two pathways for DV patterning of the wing disc.
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Nagel AC, Szawinski J, Zimmermann M, Preiss A. Drosophila Cyclin G Is a Regulator of the Notch Signalling Pathway during Wing Development. PLoS One 2016; 11:e0151477. [PMID: 26963612 PMCID: PMC4786218 DOI: 10.1371/journal.pone.0151477] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 02/29/2016] [Indexed: 01/24/2023] Open
Abstract
Notch signalling regulates a multitude of differentiation processes during Drosophila development. For example, Notch activity is required for proper wing vein differentiation which is hampered in mutants of either the receptor Notch, the ligand Delta or the antagonist Hairless. Moreover, the Notch pathway is involved in several aspects of Drosophila oogenesis as well. We have identified Drosophila Cyclin G (CycG) as a molecular interaction partner of Hairless, the major antagonist in the Notch signalling pathway, in vitro and in vivo. Loss of CycG was shown before to cause female sterility and to disturb the architecture of the egg shell. Nevertheless, Notch dependent processes during oogenesis appeared largely unaffected in cycG mutant egg chambers. Loss of CycG modified the dominant wing phenotypes of Notch, Delta and Hairless mutants. Whereas the Notch loss of function phenotype was ameliorated by a loss of CycG, the phenotypes of either Notch gain of function or of Delta or Hairless loss of function were enhanced. In contrast, loss of CycG had only a minor effect on the wing vein phenotype of mutants affecting the EGFR signalling pathway emphasizing the specificity of the interaction of CycG and Notch pathway members.
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Affiliation(s)
- Anja C. Nagel
- Institut für Genetik, Universität Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany
| | - Jutta Szawinski
- Institut für Genetik, Universität Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany
| | - Mirjam Zimmermann
- Institut für Genetik, Universität Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany
| | - Anette Preiss
- Institut für Genetik, Universität Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany
- * E-mail:
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Tognon E, Kobia F, Busi I, Fumagalli A, De Masi F, Vaccari T. Control of lysosomal biogenesis and Notch-dependent tissue patterning by components of the TFEB-V-ATPase axis in Drosophila melanogaster. Autophagy 2016; 12:499-514. [PMID: 26727288 PMCID: PMC4836007 DOI: 10.1080/15548627.2015.1134080] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
In vertebrates, TFEB (transcription factor EB) and MITF (microphthalmia-associated transcription factor) family of basic Helix-Loop-Helix (bHLH) transcription factors regulates both lysosomal function and organ development. However, it is not clear whether these 2 processes are interconnected. Here, we show that Mitf, the single TFEB and MITF ortholog in Drosophila, controls expression of vacuolar-type H(+)-ATPase pump (V-ATPase) subunits. Remarkably, we also find that expression of Vha16-1 and Vha13, encoding 2 key components of V-ATPase, is patterned in the wing imaginal disc. In particular, Vha16-1 expression follows differentiation of proneural regions of the disc. These regions, which will form sensory organs in the adult, appear to possess a distinctive endolysosomal compartment and Notch (N) localization. Modulation of Mitf activity in the disc in vivo alters endolysosomal function and disrupts proneural patterning. Similar to our findings in Drosophila, in human breast epithelial cells we observe that impairment of the Vha16-1 human ortholog ATP6V0C changes the size and function of the endolysosomal compartment and that depletion of TFEB reduces ligand-independent N signaling activity. Our data suggest that lysosomal-associated functions regulated by the TFEB-V-ATPase axis might play a conserved role in shaping cell fate.
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Affiliation(s)
- Emiliana Tognon
- a IFOM - FIRC Institute of Molecular Oncology , Milan , Italy
| | - Francis Kobia
- a IFOM - FIRC Institute of Molecular Oncology , Milan , Italy
| | - Ilaria Busi
- a IFOM - FIRC Institute of Molecular Oncology , Milan , Italy
| | | | - Federico De Masi
- b Center for Biological Sequence Analysis, Institute for Systems Biology, Technical University of Denmark , Lyngby , Denmark
| | - Thomas Vaccari
- a IFOM - FIRC Institute of Molecular Oncology , Milan , Italy
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Chou MH, Hsieh YC, Huang CW, Chen PH, Chan SP, Tsao YP, Lee HH, Wu JT, Chen SL. BCAS2 Regulates Delta-Notch Signaling Activity through Delta Pre-mRNA Splicing in Drosophila Wing Development. PLoS One 2015; 10:e0130706. [PMID: 26091239 PMCID: PMC4475048 DOI: 10.1371/journal.pone.0130706] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 05/23/2015] [Indexed: 11/19/2022] Open
Abstract
Previously, we showed that BCAS2 is essential for Drosophila viability and functions in pre-mRNA splicing. In this study, we provide strong evidence that BCAS2 regulates the activity of Delta-Notch signaling via Delta pre-mRNA splicing. Depletion of dBCAS2 reduces Delta mRNA expression and leads to accumulation of Delta pre-mRNA, resulting in diminished transcriptions of Delta-Notch signaling target genes, such as cut and E(spl)m8. Furthermore, ectopic expression of human BCAS2 (hBCAS2) and Drosophila BCAS2 (dBCAS2) in a dBCAS2-deprived fly can rescue dBCAS2 depletion-induced wing damage to the normal phenotypes. These rescued phenotypes are correlated with the restoration of Delta pre-mRNA splicing, which affects Delta-Notch signaling activity. Additionally, overexpression of Delta can rescue the wing deformation by deprivation of dBCAS2; and the depletion of dBCAS2 can restore the aberrant eye associated with Delta-overexpressing retinas; providing supporting evidence for the regulation of Delta-Notch signaling by dBCAS2. Taken together, dBCAS2 participates in Delta pre-mRNA splicing that affects the regulation of Delta-Notch signaling in Drosophila wing development.
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Affiliation(s)
- Meng-Hsuan Chou
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Yi-Chen Hsieh
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Chu-Wei Huang
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Po-Han Chen
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Shih-Peng Chan
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Yeou-Ping Tsao
- Department of Ophthalmology, Mackay Memorial Hospital, Taipei, 104, Taiwan
| | - Hsiu-Hsiang Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - June-Tai Wu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, 100, Taiwan
- * E-mail: (SLC); (JTW)
| | - Show-Li Chen
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
- * E-mail: (SLC); (JTW)
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Chip physically interacts with Notch and their stoichiometry is critical for Notch function in wing development and cell proliferation in Drosophila. Biochim Biophys Acta Gen Subj 2015; 1850:802-12. [DOI: 10.1016/j.bbagen.2014.12.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 12/15/2014] [Accepted: 12/27/2014] [Indexed: 12/17/2022]
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Legent K, Liu HH, Treisman JE. Drosophila Vps4 promotes Epidermal growth factor receptor signaling independently of its role in receptor degradation. Development 2015; 142:1480-91. [PMID: 25790850 DOI: 10.1242/dev.117960] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 02/20/2015] [Indexed: 12/12/2022]
Abstract
Endocytic trafficking of signaling receptors is an important mechanism for limiting signal duration. Components of the Endosomal Sorting Complexes Required for Transport (ESCRT), which target ubiquitylated receptors to intra-lumenal vesicles (ILVs) of multivesicular bodies, are thought to terminate signaling by the epidermal growth factor receptor (EGFR) and direct it for lysosomal degradation. In a genetic screen for mutations that affect Drosophila eye development, we identified an allele of Vacuolar protein sorting 4 (Vps4), which encodes an AAA ATPase that interacts with the ESCRT-III complex to drive the final step of ILV formation. Photoreceptors are largely absent from Vps4 mutant clones in the eye disc, and even when cell death is genetically prevented, the mutant R8 photoreceptors that develop fail to recruit surrounding cells to differentiate as R1-R7 photoreceptors. This recruitment requires EGFR signaling, suggesting that loss of Vps4 disrupts the EGFR pathway. In imaginal disc cells mutant for Vps4, EGFR and other receptors accumulate in endosomes and EGFR target genes are not expressed; epistasis experiments place the function of Vps4 at the level of the receptor. Surprisingly, Vps4 is required for EGFR signaling even in the absence of Shibire, the Dynamin that internalizes EGFR from the plasma membrane. In ovarian follicle cells, in contrast, Vps4 does not affect EGFR signaling, although it is still essential for receptor degradation. Taken together, these findings indicate that Vps4 can promote EGFR activity through an endocytosis-independent mechanism.
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Affiliation(s)
- Kevin Legent
- Kimmel Center for Biology and Medicine of the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Hui Hua Liu
- Kimmel Center for Biology and Medicine of the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Jessica E Treisman
- Kimmel Center for Biology and Medicine of the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
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Protection of armadillo/β-Catenin by armless, a novel positive regulator of wingless signaling. PLoS Biol 2014; 12:e1001988. [PMID: 25369031 PMCID: PMC4219662 DOI: 10.1371/journal.pbio.1001988] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 09/23/2014] [Indexed: 01/04/2023] Open
Abstract
This study uses an RNAi screen in Drosophila to identify a UBX protein, Armless, as a novel positive regulator of the important Wingless/Wnt signaling pathway, acting to stabilize Armadillo/?-Catenin by antagonizing its turnover. The Wingless (Wg/Wnt) signaling pathway is essential for metazoan development, where it is central to tissue growth and cellular differentiation. Deregulated Wg pathway activation underlies severe developmental abnormalities, as well as carcinogenesis. Armadillo/β-Catenin plays a key role in the Wg transduction cascade; its cytoplasmic and nuclear levels directly determine the output activity of Wg signaling and are thus tightly controlled. In all current models, once Arm is targeted for degradation by the Arm/β-Catenin destruction complex, its fate is viewed as set. We identified a novel Wg/Wnt pathway component, Armless (Als), which is required for Wg target gene expression in a cell-autonomous manner. We found by genetic and biochemical analyses that Als functions downstream of the destruction complex, at the level of the SCF/Slimb/βTRCP E3 Ub ligase. In the absence of Als, Arm levels are severely reduced. We show by biochemical and in vivo studies that Als interacts directly with Ter94, an AAA ATPase known to associate with E3 ligases and to drive protein turnover. We suggest that Als antagonizes Ter94's positive effect on E3 ligase function and propose that Als promotes Wg signaling by rescuing Arm from proteolytic degradation, spotlighting an unexpected step where the Wg pathway signal is modulated. The Wg/Wnt signaling pathway, found in most animals, is essential for regulating tissue growth and the formation of different cell types during development. Defects in the Wg/Wnt signaling relay can have serious consequences, ranging from aberrant organ patterning to malignant tumor formation. A pivotal step in the transmission of the Wg/Wnt signal is the stabilization of the protein Armadillo/β-Catenin, a key component of the pathway. However, the means by which the levels of this protein are regulated remain unclear. Here, we describe a novel control point of Armadillo/β-Catenin levels. Using RNA interference, we performed a screen in the fruit fly Drosophila melanogaster and identified Armless, a protein whose biological function was previously unknown, as a novel regulator of Wg/Wnt signaling, essential for the Wg/Wnt-dependent expression of downstream target genes. Our experiments suggest that Armless interferes with the tagging of Armadillo/β-Catenin with ubiquitin, thereby sparing it from proteasomal degradation. We also show that Armless directly interacts in vivo with Ter94, a ubiquitous ATPase involved in protein turnover. Our results suggest that Armless antagonizes Ter94's function in protein turnover, thereby acting as a positive regulator of Wg/Wnt signaling by promoting the stabilization of Armadillo/β-Catenin.
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LeBon L, Lee TV, Sprinzak D, Jafar-Nejad H, Elowitz MB. Fringe proteins modulate Notch-ligand cis and trans interactions to specify signaling states. eLife 2014; 3:e02950. [PMID: 25255098 PMCID: PMC4174579 DOI: 10.7554/elife.02950] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 08/31/2014] [Indexed: 12/31/2022] Open
Abstract
The Notch signaling pathway consists of multiple types of receptors and ligands, whose interactions can be tuned by Fringe glycosyltransferases. A major challenge is to determine how these components control the specificity and directionality of Notch signaling in developmental contexts. Here, we analyzed same-cell (cis) Notch-ligand interactions for Notch1, Dll1, and Jag1, and their dependence on Fringe protein expression in mammalian cells. We found that Dll1 and Jag1 can cis-inhibit Notch1, and Fringe proteins modulate these interactions in a way that parallels their effects on trans interactions. Fringe similarly modulated Notch-ligand cis interactions during Drosophila development. Based on these and previously identified interactions, we show how the design of the Notch signaling pathway leads to a restricted repertoire of signaling states that promote heterotypic signaling between distinct cell types, providing insight into the design principles of the Notch signaling system, and the specific developmental process of Drosophila dorsal-ventral boundary formation. DOI:http://dx.doi.org/10.7554/eLife.02950.001 In animals, cells use a process called Notch signaling to communicate with neighboring cells. During this process, a protein known as a DSL ligand from one cell binds to a protein called a Notch receptor on a neighboring cell. This triggers a series of events in the neighboring cell that change how the genes in this cell are expressed. Notch signaling is involved in many processes including the early growth of embryos, the formation of organs and limbs, and the maintenance of stem cells throughout adult life. Enzymes called Fringe enzymes can control Notch signaling by blocking or promoting the formation of the DSL ligand-Notch receptor pairs. It is also possible for a DSL ligand and a Notch receptor from the same cell to interact. This is thought to be important because it prevents an individual cell from sending and receiving Notch signals at the same time. There are several different DSL ligands, Notch receptors and Fringe enzymes, so it is difficult to determine which configurations of receptors, ligands and Fringe enzymes can enable Notch signals to be sent or received. To address this problem, LeBon et al. investigated how Fringe enzymes acted on several different DSL-Notch receptor pairs in mammalian cells, and also in fruit flies. They focused in particular on the interactions that occurred within the same cell, as the role of Fringe enzymes in this type of interaction has not been examined previously. The experiments revealed that Fringe proteins modify specific same-cell interactions in a way that enables a cell to receive one type of Notch signal from a neighboring cell and send a different type of Notch signal to another cell at the same time. More generally, these results show how an unconventional, ‘bottom-up’ approach can reveal the design principles of cell signaling systems, and suggest that it should now be possible to use these principles to try to understand which cell types send signals to which other cell types in many different contexts. DOI:http://dx.doi.org/10.7554/eLife.02950.002
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Affiliation(s)
- Lauren LeBon
- Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
| | - Tom V Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
| | - David Sprinzak
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | | | - Michael B Elowitz
- Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
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Caine C, Kasherov P, Silber J, Lalouette A. Mef2 interacts with the Notch pathway during adult muscle development in Drosophila melanogaster. PLoS One 2014; 9:e108149. [PMID: 25247309 PMCID: PMC4172597 DOI: 10.1371/journal.pone.0108149] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 08/03/2014] [Indexed: 12/22/2022] Open
Abstract
Myogenesis of indirect flight muscles (IFMs) in Drosophila melanogaster follows a well-defined cellular developmental scheme. During embryogenesis, a set of cells, the Adult Muscle Precursors (AMPs), are specified. These cells will become proliferating myoblasts during the larval stages which will then give rise to the adult IFMs. Although the cellular aspect of this developmental process is well studied, the molecular biology behind the different stages is still under investigation. In particular, the interactions required during the transition from proliferating myoblasts to differentiated myoblasts ready to fuse to the muscle fiber. It has been previously shown that the Notch pathway is active in proliferating myoblasts, and that this pathway is inhibited in developing muscle fibers. Furthermore, the Myocyte Enhancing Factor 2 (Mef2), Vestigial (Vg) and Scalloped (Sd) transcription factors are necessary for IFM development and that Vg is required for Notch pathway repression in differentiating fibers. Here we examine the interactions between Notch and Mef2 and mechanisms by which the Notch pathway is inhibited during differentiation. We show that Mef2 is capable of inhibiting the Notch pathway in non myogenic cells. A previous screen for Mef2 potential targets identified Delta a component of the Notch pathway. Dl is expressed in Mef2 and Sd-positive developing fibers. Our results show that Mef2 and possibly Sd regulate a Dl enhancer specifically expressed in the developing IFMs and that Mef2 is required for Dl expression in developing IFMs.
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Affiliation(s)
- Charlotte Caine
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Petar Kasherov
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Joël Silber
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Alexis Lalouette
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
- * E-mail:
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Collu GM, Hidalgo-Sastre A, Brennan K. Wnt-Notch signalling crosstalk in development and disease. Cell Mol Life Sci 2014; 71:3553-67. [PMID: 24942883 PMCID: PMC11113451 DOI: 10.1007/s00018-014-1644-x] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 04/17/2014] [Accepted: 05/05/2014] [Indexed: 10/25/2022]
Abstract
The Notch and Wnt pathways are two of only a handful of highly conserved signalling pathways that control cell-fate decisions during animal development (Pires-daSilva and Sommer in Nat Rev Genet 4: 39-49, 2003). These two pathways are required together to regulate many aspects of metazoan development, ranging from germ layer patterning in sea urchins (Peter and Davidson in Nature 474: 635-639, 2011) to the formation and patterning of the fly wing (Axelrod et al in Science 271:1826-1832, 1996; Micchelli et al in Development 124:1485-1495, 1997; Rulifson et al in Nature 384:72-74, 1996), the spacing of the ciliated cells in the epidermis of frog embryos (Collu et al in Development 139:4405-4415, 2012) and the maintenance and turnover of the skin, gut lining and mammary gland in mammals (Clayton et al in Nature 446:185-189, 2007; Clevers in Cell 154:274-284, 2013; Doupe et al in Dev Cell 18:317-323, 2010; Lim et al in Science 342:1226-1230, 2013; Lowell et al in Curr Biol 10:491-500, 2000; van et al in Nature 435:959-963, 2005; Yin et al in Nat Methods 11:106-112, 2013). In addition, many diseases, including several cancers, are caused by aberrant signalling through the two pathways (Bolós et al in Endocr Rev 28: 339-363, 2007; Clevers in Cell 127: 469-480, 2006). In this review, we will outline the two signalling pathways, describe the different points of interaction between them, and cover how these interactions influence development and disease.
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Affiliation(s)
- Giovanna M Collu
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK,
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50
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Xie G, Yu Z, Jia D, Jiao R, Deng WM. E(y)1/TAF9 mediates the transcriptional output of Notch signaling in Drosophila. J Cell Sci 2014; 127:3830-9. [PMID: 25015288 DOI: 10.1242/jcs.154583] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Transcriptional activation of Notch signaling targets requires the formation of a ternary complex that involves the intracellular domain of the Notch receptor (NICD), DNA-binding protein Suppressor of Hairless [Su(H), RPBJ in mammals] and coactivator Mastermind (Mam). Here, we report that E(y)1/TAF9, a component of the transcription factor TFIID complex, interacts specifically with the NICD-Su(H)-Mam complex to facilitate the transcriptional output of Notch signaling. We identified E(y)1/TAF9 in a large-scale in vivo RNA interference (RNAi) screen for genes that are involved in a Notch-dependent mitotic-to-endocycle transition in Drosophila follicle cells. Knockdown of e(y)1/TAF9 displayed Notch-mutant-like phenotypes and defects in target gene and activity reporter expression in both the follicle cells and wing imaginal discs. Epistatic analyses in these two tissues indicated that E(y)1/TAF9 functions downstream of Notch cleavage. Biochemical studies in S2 cells demonstrated that E(y)1/TAF9 physically interacts with the transcriptional effectors of Notch signaling Su(H) and NICD. Taken together, our data suggest that the association of the NICD-Su(H)-Mastermind complex with E(y)1/TAF9 in response to Notch activation recruits the transcription initiation complex to induce Notch target genes, coupling Notch signaling with the transcription machinery.
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Affiliation(s)
- Gengqiang Xie
- Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA
| | - Zhongsheng Yu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, the Chinese Academy of Sciences, Datun Road 15, Beijing 100101, China
| | - Dongyu Jia
- Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA
| | - Renjie Jiao
- Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA
| | - Wu-Min Deng
- Department of Biological Science, Florida State University, Tallahassee, FL 32304-4295, USA
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